[424B5] Inhibikase Therapeutics, Inc. Prospectus Supplement (Debt Securities)

Rhea-AI Filing Summary

Inhibikase Therapeutics, Inc. is conducting a primary offering of 46,091,739 shares of common stock and pre-funded warrants to purchase up to 22,873,779 shares of common stock at $1.45 and $1.449, respectively. The deal is expected to generate gross proceeds of about $99,997,127, with approximately $93.6 million in net proceeds after underwriting fees and expenses. The company plans to use the cash, together with existing funds, mainly to advance its lead PAH candidate IKT-001 through an adaptive Phase 3 program and for broader R&D, potential acquisitions, and general corporate purposes, which it estimates will fund operations into 2029.

Insights

Biotech capital markets analyst

Large primary raise strengthens cash runway but adds dilution.

Inhibikase Therapeutics is issuing 46,091,739 shares plus pre-funded warrants for up to 22,873,779 shares, at $1.45 and $1.449, for gross proceeds of about $99,997,127. After fees and expenses, net proceeds are estimated at roughly $93.6 million, with an option for underwriters to buy 10,344,827 additional shares.

The company states that, combined with $77.3 million in cash, cash equivalents and marketable securities as of September 30, 2025 and potential cash from existing Series A‑1 and B‑1 warrant exercises, this funding is expected to cover operating and capital needs into 2029. Proceeds are earmarked primarily for clinical development and manufacturing of IKT‑001 for PAH, other R&D, and general corporate purposes.

Risk for existing holders comes from immediate and potential future dilution: the offering is priced above the prior net tangible book value of $0.97 per share, and the company highlights an initial dilution of $0.07 per share at the $1.45 offer price, with further dilution possible as options and warrants, including the pre‑funded warrants, are exercised.

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Filed Pursuant to Rule 424(b)(5)
Registration No. 333-288213

PROSPECTUS SUPPLEMENT

(To prospectus dated June 27, 2025)

46,091,739 Shares of Common Stock

Pre-Funded Warrants to Purchase up to 22,873,779 Shares of Common Stock

We are offering 46,091,739 shares of our common stock and, in lieu of common stock to investors that so choose, pre-funded warrants to purchase up to 22,873,779 shares of common stock. The purchase price of each pre-funded warrant will equal the price per share at which shares of our common stock are being sold to the public in this offering, minus $0.001, which is the exercise price of each pre-funded warrant. The pre-funded warrants do not expire, and each pre-funded warrant will be exercisable at any time after the date of issuance, subject to an ownership limitation. This prospectus supplement also relates to the offering of the shares of common stock issuable upon exercise of such pre-funded warrants.

Our common stock is listed on the Nasdaq Capital Market under the symbol “IKT.” On November 19, 2025, the closing sale price of our common stock on the Nasdaq Capital Market, was $1.56 per share. There is no established public trading market for the pre-funded warrants, and we do not expect a market to develop. We do not intend to list the pre-funded warrants on the Nasdaq Capital Market or any other national securities exchange or nationally recognized trading system.

Investing in our securities involves a high degree of risk. Please read “Risk Factors” beginning on page S-7 of this prospectus supplement, page 2 in the accompanying prospectus, and under similar headings in the documents that are incorporated by reference herein and therein concerning factors you should carefully consider before investing in our securities.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities, or passed upon the adequacy or accuracy of this prospectus supplement or the accompanying prospectus. Any representation to the contrary is a criminal offense.

We are an “emerging growth company” and a “smaller reporting company” as defined under federal securities laws, and, as such, will be subject to reduced public company reporting requirements for this prospectus supplement and future filings. See the section titled “Prospectus Summary—Implications of Being an Emerging Growth Company and a Smaller Reporting Company.”

		PER SHARE				PER PRE-FUNDED WARRANT				TOTAL
Public offering price		$	1.45			$	1.449			$	99,997,127
Underwriting discounts and commissions (1)		$	0.087			$	0.087			$	6,000,000
Proceeds, before expenses, to us		$	1.363			$	1.362			$	93,977,127

(1) See the section titled “Underwriting” beginning on page S-23 for a description of the compensation payable to the underwriters.

The underwriters expect to deliver the shares of common stock and pre-funded warrants on or about November 24, 2025.

We have granted the underwriters an option for a period of 30 days to purchase up to an additional 10,344,827 shares of our common stock at the public offering price, less the underwriting discounts and commissions.

Joint Book-Running Managers

Jefferies BofA Securities Cantor

Lead Managers

LifeSci Capital Oppenheimer & Co.

Co-Managers

H.C. Wainwright & Co. Ladenburg Thalmann

Prospectus supplement dated November 20, 2025

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PROSPECTUS SUPPLEMENT

		PAGE
ABOUT THIS PROSPECTUS SUPPLEMENT			S-i
CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING STATEMENTS			S-iii
PROSPECTUS SUPPLEMENT SUMMARY			S-1
RISK FACTORS			S-7
DIVIDEND POLICY			S-11
USE OF PROCEEDS			S-12
DILUTION			S-13
DESCRIPTION OF PRE-FUNDED WARRANTS			S-15
MATERIAL U.S. FEDERAL INCOME TAX CONSEQUENCES FOR INVESTORS IN COMMON STOCK AND PRE-FUNDED WARRANTS			S-17
UNDERWRITING			S-23
LEGAL MATTERS			S-31
EXPERTS			S-32
WHERE YOU CAN FIND MORE INFORMATION			S-33
INCORPORATION OF CERTAIN INFORMATION BY REFERENCE			S-34

PROSPECTUS

		PAGE
ABOUT THIS PROSPECTUS			1
RISK FACTORS			2
CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS			3
THE COMPANY			5
USE OF PROCEEDS			7
SECURITIES THAT MAY BE OFFERED			8
DESCRIPTION OF CAPITAL STOCK			9
DESCRIPTION OF DEBT SECURITIES			14
DESCRIPTION OF WARRANTS			20
DESCRIPTION OF UNITS			21
PLAN OF DISTRIBUTION			24
LEGAL MATTERS			27
EXPERTS			28
WHERE YOU CAN FIND MORE INFORMATION			29
INCORPORATION BY REFERENCE			30

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ABOUT THIS PROSPECTUS SUPPLEMENT

This prospectus supplement is part of a registration statement on Form S-3 (File No. 333-288213) that we filed with the Securities and Exchange Commission (the “SEC”), utilizing a “shelf” registration process. Under this shelf registration process, we may from time to time sell any combination of the securities described in this prospectus supplement and accompanying prospectus in one or more offerings for an aggregate offering price of up to $300,000,000.

This document is in two parts. The first part is this prospectus supplement, which describes the specific terms of this offering of common stock and pre-funded warrants. The second part is the accompanying prospectus, which provides more general information, some of which may not apply to this offering. The information included or incorporated by reference in this prospectus supplement also adds to, updates and changes information contained or incorporated by reference in the accompanying prospectus. If information included or incorporated by reference in this prospectus supplement is inconsistent with the accompanying prospectus or the information incorporated by reference therein, then this prospectus supplement or the information incorporated by reference in this prospectus supplement will apply and will supersede the information in the accompanying prospectus and the documents incorporated by reference therein. However, if any statement in one of these documents is inconsistent with a statement in another document with a later date that is incorporated by reference herein, the statement in the document having the later date modifies and supersedes the earlier statement.

Before buying any of the shares of common stock or pre-funded warrants offered hereby, we urge you to read carefully this prospectus supplement and the accompanying prospectus, together with the information incorporated herein by reference as described below under the heading “Incorporation of Certain Information by Reference,” as well as the additional information described in this prospectus supplement under “Where You Can Find More Information.”

We further note that the representations, warranties and covenants made by us in any agreement that is filed as an exhibit to any document that is incorporated by reference herein were made solely for the benefit of the parties to such agreement, including, in some cases, for the purpose of allocating risk among the parties to such agreements, and should not be deemed to be a representation, warranty or covenant to you. Moreover, such representations, warranties or covenants were accurate only as of the date when made. Accordingly, such representations, warranties and covenants should not be relied on as accurately representing the current state of our affairs.

Neither we nor the underwriters have authorized anyone to provide you with information other than the information that we have provided or incorporated by reference in this prospectus supplement and the accompanying prospectus and your reliance on any unauthorized information or representation is at your own risk. You should assume that the information appearing in this prospectus supplement is accurate only as of the date of this prospectus supplement and that any information we have incorporated by reference is accurate only as of the date of the document incorporated by reference, regardless of the time of delivery of this prospectus supplement, or any sale of our common stock and pre-funded warrants. Our business, financial condition and results of operations may have changed since those dates.

We are offering to sell, and seeking offers to buy, shares of common stock and pre-funded warrants only in jurisdictions where offers and sales are permitted. The distribution of this prospectus supplement and the accompanying prospectus and the offering of the common stock and pre-funded warrants in certain jurisdictions may be restricted by law. No action is being taken in any jurisdiction outside the United States to permit a public offering of the securities or possession or distribution of this prospectus supplement or the accompanying prospectus in that jurisdiction. Persons outside the United States who come into possession of this prospectus supplement and the accompanying prospectus must inform themselves about, and observe any restrictions relating to, the offering of the common stock and pre-funded warrants and the distribution of this prospectus supplement and the accompanying prospectus outside the United States. This prospectus supplement and the accompanying prospectus do not constitute, and may not be used in connection with, an offer to sell, or a solicitation of an offer to buy, any securities offered by this prospectus supplement and the accompanying prospectus by any person in any jurisdiction in which it is unlawful for such person to make such an offer or solicitation.

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As used in this prospectus supplement, unless the context suggests otherwise, all references to “us,” “our,” “Inhibikase,” “we,” the “Company” and similar designations refer to Inhibikase Therapeutics, Inc. and its subsidiaries taken as a whole.

All references in this prospectus supplement and the accompanying prospectus to our consolidated financial statements include the related notes thereto.

We intend to apply for various trademarks that we use in connection with the operation of our business. This prospectus supplement may also contain trademarks, service marks and trade names of third parties, which are the property of their respective owners. Our use or display of third parties’ trademarks, service marks, trade names or products in this prospectus supplement is not intended to, and does not imply a relationship with, or endorsement or sponsorship by us. Solely for convenience, the trademarks, service marks and trade names referred to in this prospectus supplement may appear without the ^®, SM and ^™ symbols, but the omission of such references is not intended to indicate, in any way, that we will not assert, to the fullest extent under applicable law, our rights or the right of the applicable owner of these trademarks, service marks and trade names.

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CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING STATEMENTS

This prospectus supplement, the accompanying prospectus and the documents that we incorporate by reference, contain “forward-looking statements” within the meaning of Section 27A of the Securities Act of 1933, as amended (the “Securities Act”) and Section 21E of the Securities Exchange Act of 1934, as amended (the “Exchange Act”). All statements, other than statements of historical facts, included in this prospectus supplement and the accompanying prospectus, including the documents that we incorporate by reference, regarding our strategy, future operations, future financial position, future revenue, projected costs, prospects, plans, objectives of management and expected market growth are forward-looking statements. The words “anticipate,” “believe,” “continue,” “could,” “estimate,” “expect,” “intend,” “may,” “plan,” “potential,” “predict,” “project,” “should,” “target,” “will,” “would” and similar expressions are intended to identify forward-looking statements, although not all forward-looking statements contain these identifying words. These forward-looking statements include, among other things, statements about:

∎ the success, cost and timing of our product development activities and clinical trials, including statements regarding the timing of initiation and completion of studies or trials and related preparatory work, the period during which the results of the trials will become available, and our research and development programs;

∎ our ability to initiate and successfully enroll a Phase 3 trial in pulmonary arterial hypertension in multiple countries;

∎ our ability to initiate Phase 3 trials in pulmonary arterial hypertension in multiple countries to support regulatory approval, including our interactions with the FDA and timing related thereto;

∎ our ability to successfully complete any clinical trial;

∎ our ability to successfully manufacture our product candidates for future clinical trials or for commercial use, if approved;

∎ our ability to obtain and maintain regulatory approval, if obtained, for any product candidates;

∎ the success of competing therapies that are or become available;

∎ our ability to obtain funding for our operations, including funding necessary to complete further development and commercialization of our product candidates;

∎ the commercialization of our product candidates, if approved;

∎ future agreements with third parties in connection with the commercialization of our product candidates and any other approved product;

∎ the size and growth potential of the markets for our product candidates, if approved, and our ability to serve those markets;

∎ the rate and degree of market acceptance of our product candidates, if approved;

∎ regulatory developments in the United States and foreign countries;

∎ our ability to contract with third-party suppliers and manufacturers and their ability to perform adequately;

∎ our ability to attract and retain key scientific or management personnel;

∎ the accuracy of our estimates regarding expenses, future revenue, capital requirements and needs for additional financing;

∎ the impact of laws and regulations; and our expectations regarding our ability to obtain and maintain intellectual property protection for our product candidates;

∎ the impact of trade restrictions such as sanctions, tariffs, reciprocal and retaliatory tariffs, and other tariff-related measures; regulatory requirements, legal actions, or enforcement; and inflation rates on our business, financial condition and results of operations;

∎ the potential for another pandemic, epidemic or outbreak of an infectious disease to disrupt our business plans, product development activities, ongoing clinical trials, including the timing and enrollment of patients, the health of our employees and the strength of our supply chain;

∎ our expectations regarding our ability to obtain and maintain intellectual property protection for our product candidates;

∎ other risks and uncertainties, including those listed under the caption “Risk Factors;” and

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∎ our use of the proceeds from this offering and any other financing transaction we may undertake.

The forward-looking statements in this prospectus supplement represent our views as of the date of this prospectus supplement. We anticipate that subsequent events and developments will cause our views to change. However, while we may elect to update these forward-looking statements at some point in the future, we have no current intention of doing so except to the extent required by applicable law.

The outcome of the events described in these forward-looking statements is subject to known and unknown risks, uncertainties, and other factors. As a result of a number of known and unknown risks and uncertainties, our actual results or performance may be materially different from those expressed or implied by these forward-looking statements. You should therefore not rely on these forward-looking statements as representing our views as of any date subsequent to the date of this prospectus supplement.

We may from time-to-time provide estimates, projections and other information concerning our industry, our business and the markets for our programs and product candidates. Information that is based on estimates, forecasts, projections, market research or similar methodologies is inherently subject to uncertainties and actual events or circumstances may differ materially from events and circumstances that are assumed in this information. Unless otherwise expressly stated, we obtained this industry, business, market, and other data from our own internal estimates and research as well as from reports, research surveys, studies, and similar data prepared by market research firms and other third parties, industry, medical and general publications, government data and similar sources. While we are not aware of any misstatements regarding any third-party information presented in this prospectus supplement or the accompanying prospectus, their estimates, in particular, as they relate to projections, involve numerous assumptions, are subject to risks and uncertainties and are subject to change based on various factors. You should read this prospectus supplement, the accompanying prospectus and the documents that we reference herein and therein and have filed with the SEC as exhibits thereto completely and with the understanding that our actual future results may be materially different from any future results expressed or implied by these forward-looking statements. These estimates involve numerous assumptions, are subject to risks and uncertainties and are subject to change based on various factors.

Factors that may cause actual results to differ materially from current expectations include, among other things, those discussed in the “Risk Factors” section in this prospectus supplement, the section of the accompanying prospectus entitled “Risk Factors” and the risk factors and cautionary statements described in other documents that we file from time to time with the SEC, specifically under “Item 1A. Risk Factors” and elsewhere in our most recent Annual Report on Form 10-K for the year ended December 31, 2024 and any of our subsequent Quarterly Reports on Form 10-Q and Current Reports on Form 8-K, as applicable. Given these uncertainties, you should not place undue reliance on these forward-looking statements. Except as required by law, we assume no obligation to update or revise these forward-looking statements for any reason, even if new information becomes available in the future.

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PROSPECTUS SUPPLEMENT SUMMARY

This summary highlights selected information about us and this offering and does not contain all of the information that you should consider before investing in our securities. You should read this prospectus supplement, the accompanying prospectus and the documents incorporated by reference herein and therein carefully, especially those associated with the risks of investing in our securities discussed under “Risk Factors” beginning on page S-7 of this prospectus supplement and those identified in our most recent Annual Report on Form 10-K for the year ended December 31, 2024 and any of our subsequent Quarterly Reports on Form 10-Q, as applicable, and any subsequent reports we file with the SEC after the date of this prospectus supplement, which are incorporated by reference in this prospectus supplement, along with our consolidated financial statements and notes to those consolidated financial statements and the other information incorporated by reference in this prospectus supplement, before making an investment decision.

Our Company

We are a clinical-stage pharmaceutical company developing therapeutics to modify the course of cardiopulmonary diseases namely, Pulmonary Arterial Hypertension (“PAH”), that arise from aberrant signaling through the Abelson Tyrosine Kinase, and type III receptor tyrosine kinases including platelet derived growth factor receptors and c-KIT. Our lead product candidate is IKT-001, a prodrug of imatinib mesylate, for PAH which is an orphan indication. PAH is a progressive, life-threatening disease characterized by pulmonary vascular remodeling and elevated pulmonary vascular resistance that affects approximately 50,000 Americans. We have completed non-human primate safety studies and a bioequivalence clinical trial in healthy volunteers to determine the doses of IKT-001 that are equivalent to imatinib mesylate. Our Phase 3 study, named IMPROVE-PAH (IKT-001 for Measuring Pulmonary Vascular Resistance and Outcome Variables in a Phase 3 Evaluation of PAH), is expected to be initiated in the first quarter of 2026.

We were previously pursuing risvodetinib (also known as IkT-148009), a selective inhibitor of the non-receptor Abelson Tyrosine Kinases that targets the treatment of Parkinson’s disease, but we have discontinued and outlicensed this program.

IKT-001 and PAH

IKT-001 emerged from our medicinal chemistry program that aimed to develop improvements to drugs that inhibit Abelson Tyrosine Kinase and type III receptor tyrosine kinases. IKT-001, a novel oral prodrug of imatinib mesylate, was designed to improve areas of the molecule that might play a role in the gastrointestinal (“GI”) side effects commonly observed with oral imatinib mesylate. A three-part dose finding/dose equivalence study in 66 healthy volunteers (known as ‘the 501 trial’) was completed with IKT-001 in 2023. The study was designed to evaluate the 96-hour single-dose pharmacokinetics of imatinib delivered as IKT-001 and determine the dose relationship between IKT-001 and imatinib mesylate. Based on this study it was determined that bioequivalence was established with a 300 mg dose of IKT-001 to a dose of 230 mg of imatinib mesylate while a 500 mg dose of IKT-001 was established as bioequivalent to a dose of 383 mg of imatinib mesylate. These doses are adequate to cover the target systemically and were similar to the doses of imatinib mesylate used in the Phase 3 IMPRES trial in PAH.

On January 19, 2024, we met with the Food and Drug Administration (“FDA”) Hematological Malignancy Review Team (“Review Team”) in a Pre-New Drug Application (“pre-NDA”), meeting to discuss our bioequivalence studies of IKT-001 and its path to approval. All questions were addressed and summarized in official meeting minutes issued by the FDA on February 12, 2024. During the meeting, we inquired whether additional clinical studies would be needed to seek approval and discussed manufacturing and quality control requirements for approval. The Review Team acknowledged that the 505(b)(2) pathway appeared to be the appropriate pathway for approval of IKT-001.

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PAH is a rare disease of the pulmonary microvasculature found in 15 to 50 persons per million within the United States and Europe. The global PAH market size was valued at $7.66 billion in 2023 and is estimated to grow at a compound annual growth rate of 3.3% through 2034. Most of the treatments that constitute the standard of care (e.g. ERAs, PDE5s, prostacyclins) primarily act as vasodilators. In 2024, sotatercept was approved for the treatment of PAH on top of standard-of-care (“SOC”). Sotatercept, branded as WINREVAIR, is recombinant fusion protein that acts as a trap for transforming growth factor-beta superfamily ligands, including activin A and bone morphogenetic protein 9. These ligands may play a role in the development and progression of PAH by promoting cell proliferation and fibrosis.

Sotatercept was launched by Merck & Co in 2024 and is presently generating, on an annualized basis, approximately $1.4 billion in sales with quarter-on-quarter growth rate since launch. The success of sotatercept has created renewed enthusiasm around the anti-proliferative pathways in PAH. As previously mentioned, imatinib inhibits Abelson Tyrosine Kinase and type III receptor tyrosine kinases and through these pathways inhibits platelet-derived growth factor receptor which are involved in cell proliferation and migration as well as stem cell factor receptor (c-KIT) which modulates mast cell and hematopoietic stem cell activity. Through these targets imatinib may inhibit vascular cell proliferation, migration and fibrosis. Thus, targeting the type III receptor tyrosine kinase pathway may provide an alternate mechanism for disease modification in PAH.

The first reports of the use of imatinib in PAH were published in 2005 and 2006. A Phase 2, randomized control trial, was subsequently conducted showing clinical benefit of imatinib in PAH. In 2013, the outcome of a Phase 3 trial (IMPRES) evaluating imatinib mesylate as a treatment for PAH was reported, demonstrating that imatinib may improve key parameters associated with PAH. In this study, imatinib improved exercise capacity and hemodynamics in patients with advanced PAH but approval was precluded because of the bleeding risk associated with concomitant anti-coagulant therapy and the high discontinuation rate in the imatinib group.

As we considered revisiting the use of imatinib in PAH, we recognized that changes in SOC for these patients may have alleviated much of the safety risk previously observed for imatinib in PAH patients. This analysis prompted us to file a pre-IND (“PIND”) meeting request to discuss the application of IKT-001 as a potential disease-modifying treatment for PAH. To evaluate this further, members of the Company met with the FDA Division of Cardiology and Nephrology in a PIND meeting to discuss our plan to utilize IKT-001 in a Phase 2b efficacy, safety and tolerability study in PAH. At the meeting, the FDA confirmed that IKT-001 would be viewed as a New Molecular Entity (“NME”) and that the appropriate path for approval remained to be the 505(b)(2) statute. This opens up the possibility of IKT-001 being granted NME status and market exclusivity on approval. The FDA requested at the PIND meeting that we conduct a cell-culture based study of the human Ether-a-go-go-related Gene (“hERG”) ion channel, a standard cardiovascular safety test performed for any NME for which a new Investigative New Drug Application (“IND”) is to be opened. IKT-001 weakly inhibits hERG and imatinib has an IC50 of 14.5 uM. Following completion of this study, the IND was filed with the FDA on August 9, 2024 and we were cleared to initiate a Phase 2b trial on September 9, 2024.

On October 21, 2024, we closed a private placement with gross proceeds of approximately $110 million, before deducting placement fees and offering expenses, to support this program. If the warrants issued in such offering are exercised for cash, the total gross proceeds from the financing may be up to $275 million. We intend to use the net proceeds from the private placement to finance the initiation of a Phase 3 trial in PAH and for general corporate purposes. We have had discussions with the FDA regarding Orphan Drug Designation (“ODD”) for delivery of imatinib by IKT-001 for PAH and plan to apply for ODD once the required pre-clinical studies are complete.

More recently, a contemporary study published in the American Journal of Respiratory and Critical Care Medicine in an open label, single arm, four (4) center study with seventeen (17) patients confirmed that imatinib was generally well tolerated (with zero discontinuations for tolerance or side effects) in World Health Organization (“WHO”) Group 1 PAH population, and demonstrated a treatment effect on total pulmonary

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resistance (“TPR”) that compares favorably with other novel therapies for PAH, including sotatercept and seralutinib. Acknowledging the limitations of cross study comparisons and the small size of the study, we believe this recent study supports our thesis that systemic exposure of imatinib can be well tolerated and provide strong efficacy to patients suffering from PAH.

We currently have commercialization rights to IKT-001 and patent protection in the United States until 2033 for IKT-001 with upcoming patent application filings potentially extending patent protection for certain methods of treatment using IKT-001 until 2044.

Recent Developments

IKT-001 Development Plan

We previously planned to initiate a Phase 2b study in 150 subjects in PAH prior to advancing to a global pivotal Phase 3 study. However, we submitted a Type C Meeting request to the FDA to, among other things, obtain feedback on an immediate transition to a single pivotal Phase 3 study design.

Following receipt from the FDA of the Written Response from the Type C interaction, we now plan to initiate a two-part adaptive Phase 3 study. We expect Part A of IMPROVE-PAH will be a double blind, placebo-controlled study in 140 patients with a primary endpoint of PVR at Week 24. We expect Part B will adopt an identical format to Part A except the primary endpoint will be 6-minute walk distance at Week 24 in 346 patients. We believe this adaptive Phase 3 study design has important advantages including (1) permitting a 12-week dose-titration phase designed to get patients to the highest tolerable dose of IKT-001; (2) uninterrupted enrollment between Part A and Part B; and (3) the ability to, if necessary, undertake a sample size re-estimation for Part B based on Part A findings. Given that we were well-advanced in initiating the previous Phase 2b study design, we expect to initiate IMPROVE-PAH in the first quarter of 2026, with this study expected to be conducted in up to approximately 180 sites around the world.

Termination of ATM Prospectus

In connection with this offering, we terminated the sales agreement prospectus (the “ATM Prospectus”) filed with the Company’s registration statement on Form S-3 (File No. 333- 288213) and related to the shares of our common stock issuable pursuant to the Open Market Sale Agreement^SM, dated June 20, 2025 (the “Sales Agreement”), by and between the Company and Jefferies LLC. As of the date hereof, we did not make any sales of our common stock pursuant to the ATM Prospectus. Further, we will not make any sales of our common stock pursuant to the Sales Agreement, unless and until a new prospectus, prospectus supplement or a new registration statement is filed. Other than the termination of the ATM Prospectus, the Sales Agreement remains in full force and effect.

Corporate History and Information

We were incorporated in Delaware in 2010 as a successor to a Georgia limited liability company, and commenced operations in September 2008. Our subsidiary, IKT Securities Corporation, was incorporated in Massachusetts on December 13, 2021. On February 21, 2025, we acquired CorHepta Pharmaceuticals, Inc., a Delaware corporation, to expand our product pipeline and to strengthen our scientific leadership.

Our principal executive offices are located at 1000 N. West Street, Suite 1200, Wilmington, Delaware 19801 and our telephone number is (302) 295-3800. Our website address is http:www.inhibikase.com. The information contained in, or that can be accessed through, our website, does not constitute a part of this prospectus supplement, and is not incorporated by reference in this prospectus supplement or in any other filings we make with the SEC. We have included our website in this prospectus supplement solely as an inactive textual reference. Our common stock trades on the Nasdaq Capital Market under the symbol “IKT.”

Implications of Being an Emerging Growth Company and a Smaller Reporting Company

As a company with less than $1.235 billion in revenues during our last completed fiscal year, we qualify as an “emerging growth company” as defined in the Jumpstart Our Business Startups Act of 2012 (the “JOBS Act”).

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An emerging growth company may take advantage of specified reduced reporting requirements that are otherwise applicable generally to public companies. These reduced reporting requirements include:

∎ being permitted to only disclose two years of audited financial statements, in addition to any required unaudited interim financial statements, with correspondingly reduced “Management’s Discussion and Analysis of Financial Condition and Results of Operations” disclosure;

∎ an exemption from compliance with the auditor attestation requirement on the effectiveness of our internal control over financial reporting pursuant to the Sarbanes-Oxley Act of 2002;

∎ an exemption from compliance with any requirement that the Public Company Accounting Oversight Board may adopt regarding a supplement to the auditor’s report providing additional information about the audit and the financial statements;

∎ reduced disclosure about our executive compensation arrangements; and

∎ an exemption from the requirements to obtain a non-binding advisory vote on executive compensation or a stockholder approval of any golden parachute arrangements.

We have elected to take advantage of some, but not all, of the available benefits under the JOBS Act. Accordingly, the information contained herein may be different from the information you receive from other public companies in which you hold stock. Further, pursuant to Section 107 of the JOBS Act, as an emerging growth company, we have elected to use the extended transition period for complying with new or revised accounting standards until those standards would otherwise apply to private companies. As a result, our consolidated financial statements may not be comparable to the financial statements of issuers who are required to comply with the effective dates for new or revised accounting standards that are applicable to public companies, which may make our common stock less attractive to investors.

We will remain an emerging growth company until the earliest to occur of: (i) the end of the first fiscal year in which our annual gross revenues are $1.235 billion or more; (ii) the end of the first fiscal year in which we are deemed to be a “large accelerated filer,” as defined in the Exchange Act ; (iii) the date on which we have, during the previous three-year period, issued more than $1.0 billion in non-convertible debt securities; and (iv) December 31, 2025.

We are also a “smaller reporting company,” meaning that the market value of our shares held by non-affiliates plus the aggregate amount of gross proceeds to us as a result of this offering is less than $700.0 million and our annual revenue was less than $100.0 million during the most recently completed fiscal year. We may continue to be a smaller reporting company after this offering if either (i) the market value of our shares held by non-affiliates is less than $250.0 million or (ii) our annual revenue was less than $100.0 million during the most recently completed fiscal year and the market value of our shares held by non-affiliates is less than $700.0 million. If we are a smaller reporting company at the time we cease to be an emerging growth company, we may continue to rely on exemptions from certain disclosure requirements that are available to smaller reporting companies. Specifically, as a smaller reporting company, we may choose to present only the two most recent fiscal years of audited financial statements in our Annual Report on Form 10-K and, similar to emerging growth companies, smaller reporting companies have reduced disclosure obligations regarding executive compensation.

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THE OFFERING

Common stock offered by us 46,091,739 shares.

Pre-funded warrants offered by us We are also offering, in lieu of common stock to investors that so choose, pre-funded warrants to purchase up to 22,873,779 shares of our common stock. Each pre-funded warrant will be exercisable for one share of our common stock. The purchase price of each pre-funded warrant will equal the price per share at which shares of common stock are being sold to the public in this offering, less $0.001, which is the exercise price of each pre-funded warrant. The pre-funded warrants do not expire, and each pre-funded warrant will be exercisable at any time after the date of issuance, subject to an ownership limitation. See “Description of Pre-Funded Warrants.” This prospectus supplement also relates to the offering of the shares of our common stock issuable upon exercise of the pre-funded warrants.

Option to purchase additional shares of common stock The underwriters have a 30-day option to purchase up to an additional 10,344,827 shares of our common stock at the public offering price, less underwriting discounts and commissions.

Common stock to be outstanding after this offering 120,899,650 shares (or 131,244,477 shares, if the underwriters exercise their option in full to purchase additional shares), in each case, assuming no exercise of any pre-funded warrants offered and sold by us.

Use of Proceeds We estimate that our net proceeds from this offering will be approximately $93.6 million (or approximately $107.7 million if the underwriters exercise in full their option to purchase additional shares of our common stock), based on the public offering price of $1.45 per share of our common stock and $1.449 per pre-funded warrant, after deducting the estimated underwriting discounts and commissions and estimated offering expenses payable by us. We currently intend to use the net proceeds from this offering, together with our existing cash and cash equivalents, primarily for general corporate purposes, which may include, among other things, clinical trials, product candidate development and manufacturing activities for IKT-001 and other product candidates, other research and development activities, acquisitions of new technologies or businesses, capital expenditures, selling, general and administrative costs, and to meet working capital needs. See “Use of Proceeds” on page S-12 of this prospectus supplement for additional information.

Risk Factors Your investment involves significant risks. You should read the “Risk Factors” section of this prospectus supplement beginning on page S-7 and page 2 of the accompanying prospectus, and under similar headings in the other documents, including our most recent Annual Report on Form 10-K and any subsequent Quarterly Reports on Form 10-Q, incorporated by reference into this prospectus supplement and

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the accompanying prospectus, for a discussion of factors to consider carefully before deciding to invest in shares of our securities.

Nasdaq Capital Market symbol “IKT.”

There is no established public trading market for the pre-funded warrants, and we do not intend to list the pre-funded warrants on the Nasdaq Capital Market or any other national securities exchange or nationally recognized trading system.

All information in this prospectus supplement related to the number of shares of our common stock to be outstanding immediately after this offering is based on 74,807,911 shares of our common stock outstanding as of September 30, 2025, including 4,149,252 restricted shares of our common stock issued in connection with the acquisition of CorHepta Pharmaceuticals, Inc. in February 2025. The number of shares outstanding as of September 30, 2025 excludes:

∎ 35,797,689 shares of our common stock issuable upon the exercise of stock options outstanding as of September 30, 2025, at a weighted average exercise price of $2.11 per share as of such date;

∎ 2,056,049 shares of our common stock issuable upon the exercise and achievement of the performance criteria of our performance-based stock options outstanding as of September 30, 2025, at a weighted average exercise price of $2.35 per share as of such date;

∎ 31,424,909 shares of our common stock reserved for future issuance under our 2020 Equity Incentive Plan, as amended, as of September 30, 2025;

∎ 119,591,301 shares of our common stock issuable upon the exercise of outstanding warrants, as of September 30, 2025, at a weighted average exercise price of $1.53 per share as of such date; and

∎ 19,665,131 shares of our common stock issuable upon the exercise of pre-funded warrants outstanding, as of September 30, 2025 with an exercise price of $0.001 per share.

In addition, the number of shares outstanding immediately after this offering does not include shares of common stock that we may offer and sell in the future pursuant to the Sales Agreement. After the expiration or waiver of the lock-up period applicable to us and described under the section of this prospectus supplement titled “Underwriting,” we may offer and sell shares of our common stock having an aggregate offering price of up to $200.0 million from time to time in “at-the-market” offerings.

Unless otherwise indicated, all information in this prospectus supplement assumes (i) no exercise of the outstanding options described above, (ii) no exercise of outstanding pre-funded warrants or common warrants described above, (iii) no exercise by the underwriters of their option to purchase additional shares of our common stock and (iv) no exercise of the pre-funded warrants offered and sold in this offering.

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RISK FACTORS

Your investment in our securities involves a high degree of risk. Before deciding whether to invest in our securities, you should carefully consider the risks and uncertainties described below and in Part I, Item 1A. “Risk Factors” in our most recent Annual Report on Form 10-K for the year ended December 31, 2024, and any of our subsequent Quarterly Reports on Form 10-Q and Current Reports on Form 8-K, as applicable, together with all other information contained in this prospectus supplement, the accompanying prospectus, any related free writing prospectus and in our filings with the SEC that we have incorporated by reference herein and therein. If any of these risks actually occurs, our business, financial condition, results of operations or cash flow could be seriously harmed. This could cause the trading price of our common stock to decline, and you may lose all or part of your investment.

Risks Related to this Offering

If you purchase shares of our common stock or pre-funded warrants sold in this offering, you will experience immediate and substantial dilution. In addition, we may issue additional equity or convertible securities in the future, which may result in additional dilution to you.

Since the price per share of our common stock being offered is higher than the net tangible book value per share of our common stock, you will suffer dilution with respect to the net tangible book value of the shares of common stock or pre-funded warrants you purchase in this offering. Based on the public offering price of $1.45 per share of our common stock and $1.449 per pre-funded warrant and our net tangible book value as of September 30, 2025, if you purchase shares of common stock or pre-funded warrants in this offering, you will suffer immediate dilution of $0.07 per share with respect to the net tangible book value of the common stock. For a more detailed discussion of the foregoing, see the section entitled “Dilution” below. To the extent outstanding stock options or warrants and pre-funded warrants are exercised, there will be further dilution to investors. In addition, to the extent we need to raise additional capital in the future, under our Sales Agreement with Jefferies LLC or otherwise, and we issue additional shares of common stock or securities convertible or exchangeable for our common stock, our then existing stockholders may experience dilution and the new securities may have rights senior to those of our common stock offered in this offering.

We have broad discretion in the use of the net proceeds from this offering and may use them in ways that you and other stockholders may not approve.

We currently expect to use the net proceeds of this offering primarily for general corporate purposes, which may include, among other things, clinical trials, product candidate development and manufacturing activities for IKT-001 or other product candidates, other research and development activities, acquisitions of new technologies or businesses, and the remainder for working capital, capital expenditures and other general corporate purposes. Because of the number and variability of factors that will determine our use of the net proceeds from this offering, their ultimate use may vary substantially from their currently intended use. Our management will have broad discretion in the application of the net proceeds from this offering and you will not have the opportunity as part of your investment decision to assess whether the net proceeds are being used appropriately. Our management might not spend the net proceeds in ways that improve our results of operations or enhance the value of our common stock. The failure by our management to apply these funds effectively could result in financial losses that could have a material adverse effect on our business, cause the price of our common stock to decline and delay the development of our product candidates. Pending their use, we may invest the net proceeds from this offering in a manner that does not produce income or that loses value. See “Use of Proceeds.”

You may experience future dilution as a result of future equity offerings.

To raise additional capital, we may in the future offer additional shares of our common stock or other securities convertible into or exchangeable for our common stock at prices that may not be the same as the price per share in this offering. We may sell shares or other securities in any other offering at a price per share that is less than the price per share paid by investors in this offering, and investors purchasing shares or other securities in the future could have rights superior to existing stockholders. The price per share at which we sell additional shares of our common stock, or securities convertible or exchangeable into common stock, in future transactions may be higher or lower than the price per share paid by investors in this offering. Further, the exercise of pre-funded warrants sold in this offering will result in further dilution to the holders of our common stock.

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Sales of a substantial number of shares of our common stock in the public market after this offering could cause our stock price to fall.

Sales of a substantial number of shares of our common stock in the public market could occur at any time. If our stockholders sell, or the market perceives that our stockholders intend to sell, substantial amounts of our common stock in the public market, the market price of our common stock could decline significantly. We had 74,807,911 shares of common stock outstanding as of September 30, 2025. We filed a registration statement on Form S-3 (Registration No. 333-288213) that was declared effective on June 27, 2025, and which registers the offer and sale from time to time of a variety of securities, including common stock, preferred stock, debt securities, warrants or units pursuant to one or more offerings at prices and terms to be determined at the time of sale. To the extent shares are sold into the market pursuant to this registration statement on Form S-3, under Rule 144 of the Securities Act or otherwise, particularly in substantial quantities, the market price of our common stock could decline.

We cannot predict what effect, if any, sales of our shares in the public market or the availability of shares for sale will have on the market price of our common stock. However, future sales of substantial amounts of our common stock in the public market, including shares issued upon exercise of outstanding options or warrants, or the perception that such sales may occur, could adversely affect the market price of our common stock.

We may raise money through additional public or private offerings of our equity securities or equity-linked securities. For example, in June 2025, we entered into the Sales Agreement with Jefferies LLC pursuant to which we may offer and sell, from time to time to or through Jefferies LLC, acting as our sales agent, shares of common stock having an aggregate offering price of up to $200.0 million. As of the date of this prospectus supplement, we may issue and sell shares of our common stock having an aggregate offering price of up to $200.0 million under our “at-the-market” offering program. Any sales of our equity or equity-linked securities could have a material adverse effect on the market price of our common stock.

In connection with this offering, we and our directors and executive officers have entered into lock-up agreements covering some or all of their equity ownership for a period of 90 days following this offering. The lock-up agreements are subject to various exceptions, and we and our directors and executive officers may be released from the lock-up agreements prior to the expiration of the lock-up period at the sole discretion of Jefferies LLC and BofA Securities, Inc. See the section entitled “Underwriting.” Upon expiration or earlier release of the lock-up agreements, we and our directors and executive officers may sell previously locked-up shares into the market, which could adversely affect the market price of shares of our common stock.

We also expect that significant additional capital may be needed in the future to continue our planned operations. To raise capital, we may sell common stock, convertible securities or other equity securities in one or more transactions at prices and in a manner we determine from time to time. These sales, or the perception in the market that the holders of a large number of shares intend to sell shares, could reduce the market price of our common stock.

In addition, we have a significant number of stock options outstanding and our board of directors intends to grant additional stock options, and may also choose to issue restricted stock units, common stock, or securities convertible into or exchangeable for common stock, in the future in connection with a financing, an acquisition, employee arrangements or otherwise. In the event that the outstanding options are exercised or that we make additional issuances of common stock or other convertible or exchangeable securities, you could experience additional dilution. Furthermore, we cannot assure you that we will be able to issue shares or other securities in any other offering at a price per share that is equal to or greater than the price per share paid by investors in this offering, and investors purchasing our securities in the future may have rights superior to investors purchasing shares in this offering.

The trading price of the shares of our common stock has been and could in the future be highly volatile, and purchasers of our common stock could incur substantial losses.

The volatility of our common stock may affect the price at which you could sell the shares of our common stock, and the sale of substantial amounts of our common stock could adversely affect the price of our common stock. Our stock price is likely to continue to be volatile and subject to significant price and volume fluctuations in response to market and other factors, including those described in the sections captioned “Risk Factors” in this prospectus supplement, the accompanying prospectus and the documents incorporated by reference herein and therein.

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As a result, you may not be able to sell your shares of common stock at or above the price at which you purchase them. In addition, the stock market in general, and the Nasdaq Capital Market and the stock of biotechnology and emerging pharmaceutical companies in particular, have experienced extreme price and volume fluctuations that have often been unrelated or disproportionate to the operating performance of these companies. Broad market and industry factors may negatively affect the market price of our common stock, regardless of our actual operating performance.

The stock market in general and the market for pharmaceutical and biotechnology companies in particular have experienced extreme volatility that has often been unrelated to the operating performance of particular companies. The market price for our common stock may be influenced by many factors, including:

∎ the issuance of new equity securities pursuant to a future offering, including issuances of preferred stock;

∎ changes in interest rates;

∎ our ability to develop our product candidates;

∎ competitive developments, including announcements by competitors of new products or services or significant contracts, acquisitions, strategic partnerships, joint ventures, or capital commitments;

∎ variations in quarterly operating results or those of companies that are perceived to be similar to us;

∎ the depth and liquidity of the market for our common stock;

∎ investor perceptions of our company and the pharmaceutical and biotechnology industries generally;

∎ the degree of success of competitive products or technologies;

∎ results of clinical trials and preclinical studies, of our product candidates or those of our competitors;

∎ regulatory or legal developments in the U.S. and other countries;

∎ receipt of, or failure to obtain, regulatory approvals, including approvals of NDAs from the FDA and our ability to use accelerated regulatory pathways;

∎ developments or disputes concerning patent applications, issued patents, or other proprietary rights;

∎ the recruitment or departure of key personnel;

∎ the success of our corporate strategy and goals;

∎ the level of expenses related to our product candidates;

∎ the results of our efforts to discover, develop, acquire, or in-license additional technologies or product candidates;

∎ actual or anticipated changes in estimates as to financial results, development timelines, or recommendations by securities analysts;

∎ rumors or announcements regarding transactions involving our company or our product candidates;

∎ market conditions in the pharmaceutical and biotechnology sectors;

∎ general economic, industry, and market conditions and other national conditions; and

∎ the other factors described in this “Risk Factors” section.

There is no public market for the pre-funded warrants being offered in this offering.

There is no public trading market for the pre-funded warrants being offered in this offering, and we do not expect a market to develop. In addition, we do not intend to list the pre-funded warrants on the Nasdaq Capital Market or any other national securities exchange or nationally recognized trading system. Without an active trading market, the liquidity of the pre-funded warrants will be limited.

We will not receive a significant amount or any additional funds upon the exercise of the pre-funded warrants.

Each pre-funded warrant is exercisable for $0.001 per share of common stock underlying such pre-funded warrant, which may be paid by way of a cashless exercise, in which the holder would receive upon such exercise the net number of shares of common stock determined according to the formula set forth in the pre-funded warrant. Accordingly, we will not receive a significant amount of additional funds (if any) upon the exercise of the pre-funded warrants.

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Except for the right to participate in certain dividends and distributions, holders of the pre-funded warrants will have no rights as stockholders until such holders exercise their pre-funded warrants and acquire shares of our common stock.

Until holders of the pre-funded warrants exercise their pre-funded warrants and acquire shares of our common stock, such holders will have no rights with respect to the shares of common stock underlying such pre-funded warrants, except that the holder of a pre-funded warrant shall be entitled to participate in certain distributions, including cash dividends, if any, to all holders of our common stock for no consideration, subject to certain ownership limitations. Upon exercise of the pre-funded warrants, the holders will be entitled to exercise the rights of a holder of common stock only as to matters for which the record date occurs after the exercise date. See “Description of Pre-Funded Warrants—No Rights as a Stockholder.”

Significant holders or beneficial holders of our common stock may not be permitted to exercise pre-funded warrants that they hold.

A holder of a pre-funded warrant will not be entitled to exercise any portion of any pre-funded warrant which, upon giving effect to such exercise, would cause the aggregate number of shares of our common stock beneficially owned by the holder (together with its affiliates and other attribution parties, as defined under “Description of Pre-Funded Warrants—Exercise Limitations”) to exceed 19.99%, or if the purchaser elected prior to the issuance of pre-funded warrants to have the initial exercise limitation set at any of 4.99% or 9.99% of our outstanding common stock, such lower threshold, of the number of shares of our common stock that would be outstanding immediately after giving effect to the exercise. However, subject to certain limitations, any holder may increase or decrease such percentage to any other percentage not in excess of 19.99% upon at least 61 days’ prior notice from the holder to us. Notwithstanding the prior sentence, purchasers in this offering that select an exercise limitation of 9.99% or less will only be allowed to increase the exercise limitation above 9.99% if such increase would not result in a change of control under Nasdaq rules. As a result, you may not be able to exercise your pre-funded warrants for shares of our common stock at a time when it would be financially beneficial for you to do so. In such circumstance you could seek to sell your pre-funded warrants to realize value, but you may be unable to do so in the absence of an established trading market for the pre-funded warrants.

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DIVIDEND POLICY

We have never declared or paid cash dividends on our capital stock. We currently plan to retain all of our future earnings, if any, to finance the operation, development and growth of our business. We do not expect to pay any cash dividends on our common stock in the foreseeable future. Payment of future dividends, if any, will be at the discretion of our board of directors and will depend on our financial condition, results of operations, capital requirements, restrictions contained in current or future financing instruments, provisions of applicable law and other factors the board deems relevant. Our ability to pay dividends on our common stock may be restricted by the terms of any of our future indebtedness.

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USE OF PROCEEDS

We estimate that the net proceeds to us from the sale of the shares of common stock and pre-funded warrants to purchase shares of common stock that we are offering will be approximately $93.6 million (or approximately $107.7 million if the underwriters’ option to purchase additional shares is exercised in full), based on the public offering price of $1.45 per share of common stock and $1.449 per pre-funded warrant (which equals the price per share at which the share of our common stock are being sold to the public in this offering, minus $0.001 per share of common stock) after deducting underwriting discounts and commissions and estimated offering expenses payable by us. We will receive nominal proceeds, if any, from the exercise of the pre-funded warrants.

As of September 30, 2025, we had cash, cash equivalents and marketable securities of $77.3 million. We currently intend to use the net proceeds from this offering, together with our existing cash and cash equivalents, primarily for general corporate purposes, which may include, among other things, clinical trials, product candidate development and manufacturing activities for IKT-001 or other product candidates, other research and development activities, acquisitions of new technologies or businesses, and the remainder for working capital, capital expenditures and other general corporate purposes.

The expected use of net proceeds from this offering represents our intentions based upon our current plans and business conditions, which could change in the future as our plans and business conditions evolve. The amounts and timing of our actual expenditures may vary significantly depending on numerous factors, including the progress of our development, feedback from regulatory authorities, the status of and results from clinical trials, as well as any collaborations that we may enter into with third parties for our product candidates, and any unforeseen cash needs. We may also use a portion of the proceeds to license, acquire or invest in complementary businesses, technology, products or assets. However, we have no current commitments to do so. As a result, our management will retain broad discretion over the allocation of the net proceeds from this offering. We may find it necessary or advisable to use the net proceeds from this offering for other purposes, and we will have broad discretion in the application of net proceeds.

Based on our current operating plan, we estimate that the net proceeds from this offering, together with our existing cash, cash equivalents and marketable securities as of the date of this prospectus supplement, together with potential proceeds from exercise of all of the outstanding Series A-1 Warrants and Series B-1 Warrants, will be sufficient to enable us to fund our operating expenses and capital expenditure requirements into 2029. We have based this estimate on assumptions that may prove to be incorrect, and we could use our available capital resources sooner than we currently anticipate. Such amount will not be sufficient for us to fund our programs through regulatory approval and commercialization, and we will need to raise substantial additional capital in order to do so. To obtain the capital necessary to fund our programs through regulatory approval and commercialization, we may need to enter into additional public or private equity offerings, debt financings, or collaborations and licensing arrangements, or seek out other sources of capital. We also may elect to raise additional capital opportunistically.

Pending use of the proceeds as described above, we intend to invest the proceeds in a variety of capital preservation instruments, including high quality, investment grade instruments, certificates of deposit or direct or guaranteed obligations of the U.S. government, or may hold such proceeds as cash, until they are used for their stated purpose.

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DILUTION

If you purchase shares of our common stock or pre-funded warrants in this offering, your ownership interest will be diluted to the extent of the difference between the price per share of our common stock or pre-funded warrant you pay in this offering and the net tangible book value per share of our common stock immediately after this offering.

Our historical net tangible book value as of September 30, 2025 was approximately $72.9 million, or $0.97 per share of common stock, based upon 74,807,911 shares outstanding as of that date. Historical net tangible book value per share is equal to our total tangible assets, less our total liabilities, divided by the total number of shares outstanding.

After giving effect to our issuance and sale of shares of our common stock and pre-funded warrants at the public offering price of $1.45 per share and $1.449 per pre-funded warrant (which equals the $1.45 per share price at which shares of our common stock are being sold to the public in this offering, less the $0.001 per share exercise price of each such pre-funded warrant) (excluding shares of common stock issuable upon exercise of the pre-funded warrants, any proceeds which may be received upon exercise of the pre-funded warrants or any resulting accounting associated with the exercise of the pre-funded warrants), after deducting underwriting discounts and commissions and estimated offering expenses payable by us, our adjusted net tangible book value as of September 30, 2025 would have been $166.5 million, or $1.38 per share. This represents an immediate increase in net tangible book value of $0.41 per share to our existing stockholders, and an immediate dilution of $0.07 per share to investors purchasing shares of common stock or pre-funded warrants in the offering. Dilution per share to investors purchasing securities in this offering is determined by subtracting as adjusted net tangible book value per share after this offering from the public offering price per share of common stock (or pre-funded warrant) paid by investors.

The following table illustrates this calculation on a per share basis:

Public offering price per share							$1.45
Historical net tangible book value per share as of September 30, 2025			$0.97
Increase in net tangible book value per share attributable to investors purchasing shares of common stock or pre-funded warrants in this offering			$0.41
As adjusted net tangible book value per share as of September 30, 2025 after giving effect to this offering							$1.38
Dilution in as adjusted net tangible book value per share to investors in this offering							$0.07

If holders of pre-funded warrants exercise the pre-funded warrants offered hereby, the as-adjusted net tangible book value per share of our common stock after giving effect to this offering would be $1.16 per share, and the dilution in net tangible book value per share to investors purchasing common stock in this offering would be $0.29 per share.

If the underwriters exercise their option to purchase up to additional shares in full at the public offering price of $1.45 per share, and after deducting underwriting discounts and commissions and estimated offering expenses payable by us, the as-adjusted net tangible book value would be $1.38 per share, representing an immediate increase in net tangible book value of $0.41 per share to existing stockholders and an immediate dilution in as-adjusted net tangible book value of $0.07 per share to new investors purchasing shares of our common stock in this offering.

The foregoing tables and calculations are based on 74,807,911 shares of our common stock outstanding as of September 30, 2025, including 4,149,252 restricted shares of our common stock issued in connection with the acquisition of CorHepta Pharmaceuticals, Inc. in February 2025. The number of shares outstanding as of September 30, 2025 excludes:

∎ 35,797,689 shares of our common stock issuable upon the exercise of stock options outstanding as of September 30, 2025, at a weighted average exercise price of $2.11 per share as of such date;

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∎ 2,056,049 shares of our common stock issuable upon the exercise and achievement of the performance criteria of our performance-based stock options outstanding as of September 30, 2025, at a weighted average exercise price of $2.35 per share as of such date;

∎ 31,424,909 shares of our common stock reserved for future issuance under our 2020 Equity Incentive Plan, as amended, as of September 30, 2025;

∎ 119,591,301 shares of our common stock issuable upon the exercise of outstanding warrants, as of September 30, 2025, at a weighted average exercise price of $1.53 per share as of such date; and

∎ 19,665,131 shares of our common stock issuable upon the exercise of pre-funded warrants outstanding, as of September 30, 2025, at an exercise price of $0.001 per share.

To the extent that outstanding options or warrants are exercised, new options or other securities are issued under our equity incentive plans or we issue additional shares of common stock in the future, there will be further dilution to investors participating in this offering. In addition, we may choose to raise additional capital because of market conditions or strategic considerations, even if we believe that we have sufficient funds for our current or future operating plans. If we raise additional capital through the sale of equity or convertible debt securities, the issuance of these securities could result in further dilution to our stockholders.

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DESCRIPTION OF PRE-FUNDED WARRANTS

The following is a brief summary of certain terms and conditions of the pre-funded warrants being offered by this prospectus supplement. The following description is subject in all respects to the provisions contained in the pre-funded warrants.

Form

The pre-funded warrants will be issued as individual warrant agreements to the investors. The form of pre-funded warrant will be filed as an exhibit to our Current Report on Form 8-K that we expect to file with the SEC in connection with this offering.

Term

The pre-funded warrants do not expire.

Exercisability

Subject to certain limitations described below in “—Exercise Limitations,” the pre-funded warrants are exercisable at any time after their original issuance. The pre-funded warrants will be exercisable, at the option of each holder, in whole or in part by delivering to us a duly executed exercise notice and by payment in full of the exercise price in immediately available funds for the number of shares of common stock purchased upon such exercise. As an alternative to payment in immediately available funds, the holder may elect to exercise the pre-funded warrant through a cashless exercise, in which the holder would receive upon such exercise the net number of shares of common stock determined according to the formula set forth in the pre-funded warrant. No fractional shares of common stock will be issued in connection with the exercise of a pre-funded warrant. In lieu of any fractional shares that would otherwise be issuable, we will pay in cash to an exercising holder the fair market value, determined according to the terms of the pre-funded warrant, for any such fractional shares.

Exercise Limitations

Under the pre-funded warrants, we may not effect the exercise of any portion of any pre-funded warrant, and a holder will not be entitled to exercise any portion of any pre-funded warrant, which, upon giving effect to such exercise, would cause the aggregate number of shares of our common stock beneficially owned by the holder (together with its attribution parties (as defined below)) to exceed 19.99% of the number of shares of our common stock that would be outstanding immediately after giving effect to the exercise. Purchasers in this offering may also elect prior to the issuance of pre-funded warrants to have the initial exercise limitation set at any of 4.99% or 9.99% of our outstanding common stock. However, any holder may increase or decrease such percentage to any other percentage not in excess of 19.99%, which increase or decrease shall not become effective until 61 days after notice from the holder to us. Notwithstanding the prior sentence, purchasers in this offering that select an exercise limitation of 9.99% or less will only be allowed to increase the exercise limitation above 9.99% if such increase would not result in a change of control under Nasdaq rules. For purposes of the foregoing, “attribution parties” means, collectively, the following persons and entities with respect to any holder: (i) its direct or indirect affiliates, (ii) any person acting or who could be deemed to be acting as a Section 13(d) “group” together with the holder or any attribution parties and (iii) any other persons whose beneficial ownership of our common stock would or could be aggregated with the holder and/or any other attribution parties for purposes of Section 13(d) or Section 16 of the Exchange Act.

Exercise Price

The exercise price per whole share of our common stock purchasable upon the exercise of the pre-funded warrants is $0.001 per share of common stock. The exercise price of the pre-funded warrants and the number of shares of our common stock issuable upon exercise of the pre-funded warrants is subject to appropriate adjustment in the event of certain stock dividends and distributions, stock splits, stock combinations, reclassifications or similar events affecting our common stock.

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Charges, Taxes and Expenses

Issuance and delivery of shares of common stock upon exercise of a pre-funded warrant will be made without charge to the holder thereof for any issue or transfer tax, transfer agent fee or other incidental tax or expense (excluding any applicable stamp duties) in respect of the issuance thereof, all of which taxes and expenses shall be paid by us. However, we are not required to pay any tax that may be payable in respect of any transfer involved in the registration of any warrant shares or pre-funded warrants in a name other than that of the holder or an affiliate thereof. The holder shall be responsible for all other tax liability that may arise as a result of holding or transferring its pre-funded warrants or receiving shares upon exercise thereof.

Transferability

Subject to applicable laws, the pre-funded warrants may be assigned by the holder without our consent. The ownership of the pre-funded warrants and any transfers of the pre-funded warrants will be registered in a warrant register maintained by the warrant agent. We will initially act as warrant agent.

Exchange Listing

We do not plan on applying to list the pre-funded warrants on the Nasdaq Capital Market, any other national securities exchange or any other nationally recognized trading system.

Fundamental Transactions

In the event of a “fundamental transaction” (as described in the pre-funded warrants and generally including but not limited to certain reclassifications of our common stock, the sale, transfer or other disposition of all or substantially all of our properties or assets, our consolidation or merger with or into another person, the tender and acceptance for payment of shares representing more than 50% of the voting power of our capital stock pursuant to any tender or exchange offer (whether by us or another person), and the acquisition by another person of more than 50% of the voting power of our capital stock pursuant to a stock purchase agreement or other business combination, including a reorganization, recapitalization or spin-off (except for any such transaction in which our stockholders immediately prior to such transaction maintain, in substantially the same proportions, voting power of us immediately after the transaction)), upon consummation of such a fundamental transaction, the holders of the pre-funded warrants will be entitled to receive upon exercise of the pre-funded warrants the kind and amount of securities, cash or other property that the holders would have received had they exercised the pre-funded warrants in full immediately prior to such fundamental transaction without regard to any limitations on exercise contained in the pre-funded warrants.

No Rights as a Stockholder

Except by virtue of such holder’s ownership of shares of our common stock, the holder of a pre-funded warrant does not have the rights or privileges of a holder of our common stock, including any voting rights, until the holder exercises the pre-funded warrant. In the event of certain distributions, including cash dividends, if any, to all holders of our common stock for no consideration, the holder of a pre-funded warrant shall be entitled to participate in such distributions to the same extent as if such holder held the number of shares of our common stock acquirable upon complete exercise of its pre-funded warrant (without regard to any limitations on exercise). If such distribution would result in such holder and the other attribution parties exceeding the exercise limitations described above, a portion of such distribution shall be held in abeyance for the benefit of such holder until such time as the ownership limitations would not be exceeded.

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MATERIAL U.S. FEDERAL INCOME TAX CONSIDERATIONS FOR INVESTORS IN OUR COMMON STOCK AND PRE-FUNDED WARRANTS

The following summary describes certain material U.S. federal income tax considerations of the acquisition, ownership and disposition of our common stock and pre-funded warrants acquired in this offering. This discussion does not address all aspects of U.S. federal income taxes, does not discuss the potential application of the alternative minimum tax, the Medicare Contribution tax on net investment income, or the special tax accounting rules under Section 451(b) of the Code and does not deal with state or local taxes, U.S. federal gift and estate tax laws or any non-U.S. tax consequences that may be relevant to investors in light of their particular circumstances.

Special rules different from those described below may apply to certain investors that are subject to special treatment under the Internal Revenue Code of 1986, as amended (the “Code”), such as:

∎ insurance companies, banks and other financial institutions;

∎ tax-exempt organizations (including private foundations) and tax-qualified retirement plans;

∎ foreign governments and international organizations;

∎ broker-dealers and traders in securities;

∎ U.S. expatriates and certain former citizens or long-term residents of the United States;

∎ Non-U.S. Holders (as defined below) that own or are deemed to own (directly, indirectly or by attribution) more than 5% of our common stock and/or our pre-funded warrants;

∎ “controlled foreign corporations,” “passive foreign investment companies” and corporations that accumulate earnings to avoid U.S. federal income tax;

∎ persons that hold our common stock or pre-funded warrants as part of a “straddle,” “hedge,” “conversion transaction,” “synthetic security” or integrated investment or other risk reduction strategy;

∎ U.S. Holders (as defined below) whose functional currency for U.S. tax purposes is not the U.S. dollar;

∎ persons who do not hold our common stock or pre-funded warrants as “capital assets” within the meaning of Section 1221 of the Code (generally, for investment purposes);

∎ regulated investment companies;

∎ pension plans;

∎ “qualified foreign pension funds” as defined in Section 897(l)(2) of the Code and entities all of the interests of which are held by qualified foreign pension funds;

∎ persons holding the Securities as “qualified small business stock” within the meaning of Section 1202 of the Code, or “Section 1244 stock” under Section 1244 of the Code;

∎ persons who acquired the Securities in a transaction subject to the gain rollover provisions of the Code (including Section 1045 of the Code);

∎ persons deemed to sell our common stock or pre-funded warrants under the constructive sale provisions of the Code; and

∎ persons who hold or receive our common stock or pre-funded warrants pursuant to the exercise of any employee stock option or otherwise as compensation.

Such investors are urged to consult their own tax advisors to determine the U.S. federal, state, local and other tax consequences that may be relevant to them.

In addition, this discussion does not address the tax treatment of partnerships or other pass-through entities or persons who hold our common stock or pre-funded warrants through partnerships or other entities which are treated as pass-through entities for U.S. federal income tax purposes. If a partnership or other pass-through entity holds our common stock or pre-funded warrants, the tax treatment of a partner will generally depend upon the status of the partner and the activities of the partnership or other pass-through entity. A partner in a partnership or other pass-through entity that will hold our common stock or pre-funded warrants should consult his, her or its own tax advisor regarding the tax consequences of the ownership and disposition of our common stock or pre-funded warrants through a partnership or other pass-through entity, as applicable.

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Furthermore, the discussion below is based upon the provisions of the Code, and Treasury regulations, rulings and administrative pronouncements of the Internal Revenue Service (the “IRS”) and judicial decisions thereunder, as of the date hereof, and such authorities may be repealed, revoked or modified, possibly retroactively, and are subject to differing interpretations which could result in U.S. federal income tax consequences different from those discussed below. We have not requested a ruling from the IRS, with respect to the statements made and the conclusions reached in the following summary, and there can be no assurance that the IRS will agree with such statements and conclusions or will not take a contrary position regarding the tax consequences described herein, or that any such contrary position would not be sustained by a court.

For the purposes of this discussion, a “U.S. Holder” means a beneficial owner of our common stock or pre-funded warrants, other than a partnership or other pass-through entity, that is, for U.S. federal income tax purposes, (a) an individual who is a citizen or resident of the United States, (b) a corporation (or other entity taxable as a corporation for U.S. federal income tax purposes), created or organized in or under the laws of the United States, any state thereof or the District of Columbia, (c) an estate, the income of which is subject to U.S. federal income taxation regardless of its source, or (d) a trust if it (1) is subject to the primary supervision of a court within the United States and one or more ”United States persons” (within the meaning of Section 7701(a)(30) of the Code) have the authority to control all substantial decisions of the trust or (2) has a valid election in effect under applicable U.S. Treasury regulations to be treated as a United States person.

A “Non-U.S. Holder” means a beneficial owner of our common stock or pre-funded warrants, that is not a partnership or other pass-through entity, a U.S. Holder.

An individual non-U.S. citizen may, in some cases, be deemed to be a resident alien (as opposed to a nonresident alien) by virtue of being present in the United States for at least 31 days in the calendar year and for an aggregate of at least 183 days during a three-year period ending in the current calendar year. Generally, for this purpose, all the days present in the current year, one-third of the days present in the immediately preceding year, and one-sixth of the days present in the second preceding year, are counted.

Resident aliens are generally subject to U.S. federal income tax as if they were U.S. citizens. Individuals who are uncertain of their status as resident or nonresident aliens for U.S. federal income tax purposes are urged to consult their own tax advisors regarding the U.S. federal income tax consequences of the ownership or disposition of our common stock or pre-funded warrants.

PERSONS CONSIDERING THE PURCHASE OF OUR COMMON STOCK OR PRE-FUNDED WARRANTS PURSUANT TO THIS OFFERING SHOULD CONSULT THEIR OWN TAX ADVISORS CONCERNING THE U.S. FEDERAL INCOME TAX CONSEQUENCES OF ACQUIRING, OWNING AND DISPOSING OF OUR COMMON STOCK OR PRE-FUNDED WARRANTS IN LIGHT OF THEIR PARTICULAR SITUATIONS AS WELL AS ANY CONSEQUENCES ARISING UNDER THE LAWS OF ANY OTHER TAXING JURISDICTION, INCLUDING ANY STATE, LOCAL OR NON-U.S. TAX CONSEQUENCES OR ANY U.S. FEDERAL NON-INCOME TAX CONSEQUENCES, AND THE POSSIBLE APPLICATION OF TAX TREATIES.

Characterization of the Pre-Funded Warrants for Tax Purposes

Although the characterization of the pre-funded warrants for U.S. federal income tax purposes is not entirely clear, because the exercise price of the pre-funded warrants is a nominal amount, we intend to treat the pre-funded warrants as our common stock for U.S. federal income tax purposes and a holder of pre-funded warrants should generally expect to be taxed in the same manner as a holder of common stock as described below. Accordingly, for U.S. federal income tax purposes, no gain or loss should be recognized upon the exercise of a pre-funded warrant (except to the extent of cash received in lieu of a fractional share), and upon exercise, the holding period of the share of common stock received should include the holding period of the pre-funded warrant. Similarly, the tax basis of a share of common stock received upon exercise of a pre-funded warrant should include the tax basis of the pre-funded warrant increased by the exercise price of $0.001 per share. In certain circumstances, the pre-funded warrants may be exercised on a cashless basis. The balance of this discussion generally assumes that the characterization described above is respected for U.S. federal income tax purposes.

Our position with respect to the characterization of pre-funded warrants is not binding on the IRS and the IRS may treat the pre-funded warrants as warrants to acquire our common stock and, if so, the amount and character of a

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holder’s gain with respect to an investment in our pre-funded warrants could change. Each holder should consult its tax advisor regarding the characterization of pre-funded warrants for U.S. federal income tax purposes, and the consequences of an investment in the pre-funded warrants based on such holder’s own particular facts and circumstances.

Tax Consequences to U.S. Holders

Distributions on Common Stock and Pre-funded Warrants

As stated under “Dividend Policy,” we do not expect to make distributions on our common stock (or pre-funded warrants) in the foreseeable future. In the event that we do make distributions of cash or other property, distributions paid on common stock (or pre-funded warrants) will be treated as a dividend to the extent paid out of our current or accumulated earnings and profits (as determined under U.S. federal income tax principles), and will be includible in your income as ordinary income when received. However, with respect to dividends received by individuals, such dividends are generally taxed at the lower applicable qualified dividends rate, provided certain holding period and other requirements are satisfied. Distributions in excess of our current and accumulated earnings and profits will be treated as a return of capital to the extent of a U.S. Holder’s tax basis in the common stock (or pre-funded warrants) and thereafter as capital gain from the sale or exchange of such common stock (or pre-funded warrants). The tax treatment of such gain is further described in “—Sale or Other Disposition of Common Stock or Pre-funded Warrants” below. Dividends received by a corporation may be eligible for a dividends received deduction, subject to applicable limitations. Any such distributions will also be subject to the discussions below under the section titled “—Information Reporting and Backup Withholding.”

A U.S. Holder of a pre-funded warrant is entitled to receive certain distributions paid with respect to common stock prior to the exercise of the pre-funded warrant and, in such case, would be taxed in the same manner as a U.S. Holder of common stock that receives such a distribution. However, under certain circumstances, it is possible for the distributions to be held in abeyance for the U.S. Holder until a pre- funded warrant is exercised or the ownership limitations (described under “Description of Pre-Funded Warrants”) would not be exceeded, at which time such U.S. Holder shall be entitled to receive distributions. It is possible that such entitlement to distributions could cause the declaration of a distribution on our common stock to be currently taxable to U.S. Holders of pre-funded warrants, including under the principles governing Section 305 of the Code, even though the holders will not receive such distributions until a future date. Additionally, it is possible that other adjustments to the terms of the pre-funded warrants can be considered a constructive distribution under Section 305 of the Code. A holder of a pre-funded warrant should consult its tax advisor regarding the tax treatment of any distribution with respect to such pre-funded warrant that is held in abeyance in connection with any applicable limitation on the holder’s beneficial ownership of our common stock and the tax treatment of any other adjustments to the pre-funded warrants.

Sale or Other Disposition of Common Stock or Pre-funded Warrants

For U.S. federal income tax purposes, gain or loss realized on the sale or other disposition of common stock or pre-funded warrants by a U.S. Holder will be capital gain or loss, and will be long-term capital gain or loss if the U.S. Holder has held the common stock or pre-funded warrants for more than one year. The amount of the gain or loss will equal the difference between the U.S. holder’s adjusted tax basis in the common stock or pre-funded warrants disposed of and the amount realized on the disposition. Long-term capital gains recognized by non-corporate U.S. Holders will be subject to reduced tax rates. The deductibility of capital losses is subject to limitations.

Information Reporting and Backup Withholding

Information reporting requirements generally will apply to any distributions (including deemed distributions) on our common stock and pre-funded warrants, constructive distributions on our pre-funded warrants, and gross proceeds on the sale or other disposition of our common stock and pre-funded warrants, unless the U.S. Holder is an exempt recipient (such as certain corporations), regardless of whether any tax was actually withheld. Backup withholding (currently at a 24% rate) will apply to those payments if the U.S. Holder fails to provide its correct taxpayer identification number, or certification of exempt status, or if the U.S. Holder is notified by the IRS that it has failed to report in full payments of interest and dividend income. Any amounts withheld under the backup withholding rules will be allowed as a refund or a credit against a U.S. Holder’s U.S. federal income tax liability provided the required information is furnished timely to the IRS. U.S. Holders should consult their tax advisors regarding their

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qualification for an exemption from backup withholding, the procedures for obtaining such an exemption, and the process for obtaining a refund or credit of any overpaid amount.

Tax Consequences to Non-U.S. Holders

Distributions on Common Stock and Pre-funded Warrants

As stated under “Dividend Policy,” we do not expect to make any distributions on our common stock (or pre-funded warrants) in the foreseeable future. If we do make distributions on our common stock (or pre-funded warrants), however, such distributions made to a Non-U.S. Holder will constitute dividends for U.S. tax purposes to the extent paid out of our current or accumulated earnings and profits (as determined under U.S. federal income tax principles). Distributions in excess of our current and accumulated earnings and profits will constitute a return of capital that is applied against and reduces, but not below zero, a Non-U.S. Holder’s adjusted tax basis in our common stock (or pre-funded warrants). Any remaining excess will be treated as gain realized as described below under the section titled “—Sale or Other Disposition of Common Stock and Pre-funded Warrants.”

Subject to the discussion below under the sections titled “—Information Reporting and Backup Withholding” and “—Foreign Accounts,” any distribution on our common stock (or pre-funded warrants) that is treated as a dividend paid to a Non-U.S. Holder that is not effectively connected with the holder’s conduct of a trade or business in the United States will generally be subject to withholding tax at a 30% rate or such lower rate as may be specified by an applicable income tax treaty between the United States and the Non-U.S. Holder’s country of residence. To obtain a reduced rate of withholding under a treaty, a Non-U.S. Holder generally will be required to provide the applicable withholding agent with a properly executed IRS Form W-8BEN, IRS Form W-8BEN-E or other appropriate form, certifying the Non-U.S. Holder’s entitlement to benefits under that treaty. Such form must be provided prior to the payment of dividends and must be updated periodically. If a Non-U.S. Holder holds stock through a financial institution or other agent acting on the holder’s behalf, the holder will be required to provide appropriate documentation to such agent. The holder’s agent may then be required to provide certification to the applicable withholding agent, either directly or through other intermediaries. A Non-U.S. holder that is eligible for a reduced rate of U.S. withholding tax under an income tax treaty should consult with its own tax advisor to determine if such holder is able to obtain a refund or credit of any excess amounts withheld by timely filing an appropriate claim for a refund with the IRS.

We (or any applicable withholding agent) generally are not required to withhold tax on dividends paid (or constructive dividends deemed paid) to a Non-U.S. Holder that are effectively connected with the holder’s conduct of a trade or business within the United States (and, if required by an applicable income tax treaty, are attributable to a permanent establishment or fixed base that the holder maintains in the United States) if a properly executed IRS Form W-8ECI, stating that the dividends are so connected, is furnished to us (or, if shares of our common stock are held through a financial institution or other agent, to the applicable withholding agent). In general, such effectively connected dividends will be subject to U.S. federal income tax on a net income basis at the regular rates applicable to U.S. persons, unless a specific treaty exemption applies. A corporate Non-U.S. Holder receiving effectively connected dividends may also be subject to an additional “branch profits tax,” which is imposed, under certain circumstances, at a rate of 30% (or such lower rate as may be specified by an applicable treaty) on the corporate Non-U.S. Holder’s effectively connected earnings and profits, subject to certain adjustments.

A Non-U.S. Holder of a pre-funded warrant is entitled to receive certain distributions paid with respect to common stock prior to the exercise of the pre-funded warrant and, in such case, would be taxed in the same manner as a Non-U.S. Holder of common stock that receives such a distribution. However, under certain circumstances, it is possible for the distribution to be held in abeyance for a Non-U.S. Holder until a pre-funded warrant is exercised or the ownership limitations (described under “Description of Pre-Funded Warrants”) would not be exceeded, at which time the Non-U.S. Holder shall be entitled to receive distributions. It is possible that such entitlement to distributions could cause the declaration of a distribution on our common stock to be currently taxable to Non-U.S. Holders of pre-funded warrants, including under the principles governing Section 305 of the Code, even though such holders will not receive the distributions until a future date. Additionally, it is possible that other adjustments to the terms of the pre-funded warrants can be considered a constructive distribution under Section 305 of the Code. A holder of a pre-funded warrant should consult its tax advisor regarding the tax treatment of any distribution with

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respect to such pre-funded warrant that is held in abeyance in connection with any applicable limitation on the holder’s beneficial ownership of our common stock and the tax treatment of any other adjustments to the pre-funded warrants.

See also the section below titled “—Foreign Accounts” for additional withholding rules that may apply to dividends paid to certain foreign financial institutions or non-financial foreign entities.

Sale or Other Disposition of Common Stock and Pre-funded Warrants

Subject to the discussion below under the sections titled “—Information Reporting and Backup Withholding” and “—Foreign Accounts,” a Non-U.S. Holder generally will not be subject to U.S. federal income or withholding tax with respect to gain realized on a sale or other disposition of our common stock or pre-funded warrants unless (a) the gain is effectively connected with a trade or business of the Non-U.S. Holder in the United States (and, if required by an applicable income tax treaty, is attributable to a permanent establishment or fixed base that the Non-U.S. Holder maintains in the United States), (b) the Non-U.S. Holder is a nonresident alien individual and is present in the United States for a period or periods aggregating 183 or more days in the taxable year of the disposition and certain other conditions are met, or (c) we are or have been a “United States real property holding corporation” within the meaning of Code Section 897(c)(2), unless any class of our stock is regularly traded on an established securities market and the Non-U.S. Holder disposes of such class of stock and holds no more than 5% of such class of stock, directly or indirectly, actually or constructively, during the shorter of the 5-year period ending on the date of the disposition or the period that the Non-U.S. Holder held such class of stock. Non-U.S. Holders of pre-funded warrants are urged to consult their own tax advisors regarding application of the “regularly traded” exception from United States real property interest status if we are a United States real property holding corporation.

If you are a Non-U.S. Holder described in (a) above, you will be required to pay tax on the net gain derived from the sale at the regular U.S. federal income tax rates applicable to U.S. persons, unless a specific treaty exemption applies. Corporate Non-U.S. Holders described in (a) above may also be subject to the additional branch profits tax at a 30% rate or such lower rate as may be specified by an applicable income tax treaty. An individual Non-U.S. Holder described in (b) above will be required to pay a flat 30% tax on the gain derived from the sale, which gain may be offset by certain U.S. source capital losses (even though such holder is not considered a resident of the United States), provided such holder has timely filed U.S. federal income tax returns with respect to such losses. With respect to (c) above, in general, we would be a U.S. real property holding corporation if interests in U.S. real estate comprised (by fair market value) at least half of our worldwide real property interests plus our other assets used or held for use in a trade or business. We believe that we are not, and do not anticipate becoming, a U.S. real property holding corporation. However, there can be no assurance that we will not become a U.S. real property holding corporation in the future. Special rules may apply to holders of pre-funded warrants. Non-U.S. Holders of pre-funded warrants should consult their own tax advisors regarding the application of these rules to pre-funded warrants.

Information Reporting and Backup Withholding

Generally, we or certain financial middlemen must report information to the IRS with respect to any distributions we pay on our common stock or pre-funded warrants and any constructive distributions deemed paid on pre-funded warrants including the amount of any such distributions, the name and address of the recipient, and the amount, if any, of tax withheld. A similar report is sent to the holder to whom any such distributions are paid. Pursuant to tax treaties or certain other agreements, the IRS may make its reports available to tax authorities in the recipient’s country of residence.

Dividends paid by us (or our paying agents) to a Non-U.S. Holder may also be subject to U.S. backup withholding. U.S. backup withholding generally will not apply to a Non-U.S. Holder who provides a properly executed IRS Form W-8BEN or IRS Form W-8BEN-E, as applicable, or otherwise establishes an exemption, provided that the applicable withholding agent does not have actual knowledge or reason to know the holder is a U.S. person.

Under current U.S. federal income tax law, U.S. information reporting and backup withholding requirements generally will apply to the proceeds of a disposition of our common stock or pre-funded warrants effected by or through a U.S. office of any broker, U.S. or non-U.S., unless the Non-U.S. Holder provides a properly executed IRS Form W-8BEN or IRS Form W-8BEN-E, as applicable, or otherwise meets documentary evidence requirements for

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establishing non-U.S. person status or otherwise establishes an exemption. Generally, U.S. information reporting and backup withholding requirements will not apply to a payment of disposition proceeds to a Non-U.S. Holder where the transaction is effected outside the United States through a non-U.S. office of a non-U.S. broker. Information reporting and backup withholding requirements may, however, apply to a payment of disposition proceeds if the broker has actual knowledge, or reason to know, that the holder is, in fact, a U.S. person. For information reporting purposes, certain brokers with substantial U.S. ownership or operations will generally be treated in a manner similar to U.S. brokers.

Backup withholding is not an additional tax. If backup withholding is applied to a Non-U.S. Holder, such Non-U.S. holder should consult with its own tax advisor to determine whether such Non-U.S. Holder has overpaid U.S. federal income tax, and whether such Non-U.S. holder is able to obtain a tax refund or credit of the overpaid amount.

Foreign Accounts

In addition to, and separately from the withholding rules described above, U.S. federal withholding taxes may apply under the Foreign Account Tax Compliance Act (the “FATCA”), on certain types of payments, including dividends to non-U.S. financial institutions and certain other non-U.S. entities. Specifically, a 30% withholding tax may be imposed on dividends paid in respect of our common stock or pre-funded warrants, constructive distributions deemed paid with respect to pre-funded warrants and the gross proceeds of the disposition of our common stock or pre-funded warrants paid to a “foreign financial institution” or a “non-financial foreign entity” (each as defined in the Code), unless (1) the foreign financial institution agrees to undertake certain diligence and reporting obligations, (2) the non-financial foreign entity either certifies it does not have any “substantial United States owners” (as defined in the Code) or furnishes identifying information regarding each substantial United States owner, or (3) the foreign financial institution or non-financial foreign entity otherwise qualifies for an exemption from these rules. The 30% federal withholding tax described in this paragraph cannot be reduced under an income tax treaty with the United States. If the payee is a foreign financial institution and is subject to the diligence and reporting requirements in (1) above, it must enter into an agreement with the U.S. Department of the Treasury requiring, among other things, that it undertake to identify accounts held by certain “specified United States persons” or “United States-owned foreign entities” (each as defined in the Code), annually report certain information about such accounts, and withhold 30% on certain payments to non-compliant foreign financial institutions and certain other account holders. Foreign financial institutions located in jurisdictions that have an intergovernmental agreement with the United States governing FATCA may be subject to different rules.

The Treasury Secretary has issued proposed regulations providing that the withholding provisions under FATCA do not apply with respect to payment of gross proceeds from a sale or other disposition, which may be relied upon by taxpayers until final regulations are issued. Prospective investors should consult their tax advisors regarding the potential application of withholding under FATCA to their investment in our common stock or pre-funded warrants.

EACH PROSPECTIVE INVESTOR SHOULD CONSULT ITS OWN TAX ADVISOR REGARDING THE TAX CONSEQUENCES OF ACQUIRING, OWNING AND DISPOSING OF OUR COMMON STOCK AND PRE-FUNDED WARRANTS, INCLUDING THE CONSEQUENCES OF ANY PROPOSED CHANGE IN APPLICABLE LAW, AS WELL AS TAX CONSEQUENCES ARISING UNDER ANY STATE, LOCAL, NON-U.S. OR U.S. FEDERAL NON-INCOME TAX LAWS SUCH AS ESTATE AND GIFT TAX.

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UNDERWRITING

Subject to the terms and conditions set forth in the underwriting agreement, among us and Jefferies LLC, BofA Securities, Inc. and Cantor Fitzgerald & Co., as the representatives of the underwriters named below and the joint book-running managers of this offering, we have agreed to sell to the underwriters, and each of the underwriters has agreed, severally and not jointly, to purchase from us the respective number of shares of common stock and pre-funded warrants shown opposite its name below:

UNDERWRITER		NUMBER OF SHARES				NUMBER OF PRE-FUNDED WARRANTS
Jefferies LLC			16,132,109				8,005,823
BofA Securities, Inc.			11,522,935				5,718,445
Cantor Fitzgerald & Co.			9,218,348				4,574,756
LifeSci Capital LLC			3,456,880				1,715,533
Oppenheimer & Co. Inc.			3,456,880				1,715,533
H.C. Wainwright & Co., LLC			1,382,752				686,213
Ladenburg Thalmann & Co. Inc.			921,835				457,476
Total			46,091,739				22,873,779

The underwriting agreement provides that the obligations of the several underwriters are subject to certain conditions precedent such as the receipt by the underwriters of officers’ certificates and legal opinions and approval of certain legal matters by their counsel. The underwriting agreement provides that the underwriters will purchase all of the shares of common stock and pre-funded warrants if any of them are purchased. If an underwriter defaults, the underwriting agreement provides that the purchase commitments of the non-defaulting underwriters may be increased or the underwriting agreement may be terminated. We have agreed to indemnify the underwriters and certain of their controlling persons against certain liabilities, including liabilities under the Securities Act, and to contribute to payments that the underwriters may be required to make in respect of those liabilities.

The underwriters have advised us that, following the completion of this offering, they currently intend to make a market in the common stock as permitted by applicable laws and regulations. However, the underwriters are not obligated to do so, and the underwriters may discontinue any market-making activities at any time without notice in their sole discretion. Accordingly, no assurance can be given as to the liquidity of the trading market for the common stock, that you will be able to sell any of the common stock held by you at a particular time or that the prices that you receive when you sell will be favorable.

The underwriters are offering the shares of common stock and pre-funded warrants subject to their acceptance of the shares of common stock and pre-funded warrants from us and subject to prior sale. The underwriters reserve the right to withdraw, cancel or modify offers to the public and to reject orders in whole or in part. The underwriters have not been engaged to act as warrant agent for the pre-funded warrants or to act as underwriter or agent or otherwise participate in the issuance of the shares of our common stock upon the exercise of the pre-funded warrants.

Commission and Expenses

The underwriters have advised us that they propose to offer the shares of common stock and pre-funded warrants to the public at the public offering price set forth on the cover page of this prospectus supplement and to certain dealers, which may include the underwriters, at that price less a concession not in excess of $0.0522 per share of common stock and $0.0522 per pre-funded warrant. After the offering, the public offering price, concession and reallowance to dealers may be reduced by the representatives. No such reduction will change the amount of proceeds to be received by us as set forth on the cover page of this prospectus supplement.

The following table shows the public offering price, the underwriting discounts and commissions that we are to pay the underwriters and the proceeds, before expenses, to us in connection with this offering. Such amounts are shown assuming both no exercise and full exercise of the underwriters’ option to purchase additional shares.

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		PER SHARE												TOTAL
		WITHOUT OPTION TO PURCHASE ADDITIONAL SHARES				WITH OPTION TO PURCHASE ADDITIONAL SHARES				PER PRE-FUNDED WARRANT				WITHOUT OPTION TO PURCHASE ADDITIONAL SHARES				WITH OPTION TO PURCHASE ADDITIONAL SHARES
Public offering price		$	1.45			$	1.45			$	1.449			$	99,977,127			$	114,977,126
Underwriting discounts and commissions paid by us		$	0.087			$	0.087			$	0.087			$	6,000,000			$	6,900,000
Proceeds to us, before expenses		$	1.363			$	1.363			$	1.362			$	93,977,127			$	108,077,126

We estimate expenses payable by us in connection with this offering, other than the underwriting discounts and commissions referred to above, will be approximately $360,000. We have also agreed to reimburse the underwriters for up to $40,000 for their Financial Industry Regulatory Authority, Inc. (FINRA) counsel fee. In accordance with FINRA Rule 5110, this reimbursed fee is deemed underwriting compensation for this offering.

Listing

Our common stock is listed on Nasdaq under the trading symbol “IKT.” There is no established market for the pre-funded warrants, and we do not expect a trading market to develop. We do not intend to list the pre-funded warrants on any securities exchange or nationally recognized trading system, including Nasdaq. Without a trading market, the liquidity of the pre-funded warrants will be extremely limited.

Option to Purchase Additional Shares

We have granted to the underwriters an option, exercisable for 30 days from the date of this prospectus supplement, to purchase, from time to time, in whole or in part, up to an aggregate of 10,344,827 shares from us at the public offering price set forth on the cover page of this prospectus supplement, less underwriting discounts and commissions. If the underwriters exercise this option, each underwriter will be obligated, subject to specified conditions, to purchase a number of additional shares proportionate to that underwriter’s initial purchase commitment as indicated in the table above. This option may be exercised only if the underwriters sell more shares than the total number set forth on the cover page of this prospectus supplement.

No Sales of Similar Securities

We, our executive officers and our directors have agreed, subject to specified exceptions (such as the sale of our common stock in “at-the-market” offerings pursuant to our Sales Agreement; provided, that no sales shall be made until the earlier of the (x) exercise in full by the Underwriters of their option to purchase additional shares of our common stock and (y) 30 days from the date of this prospectus supplement), not to directly or indirectly:

∎ sell, offer or contract to sell or lend any of our securities;

∎ effect any short sale, or establish or increase any “put equivalent position” (as defined in Rule 16a-l(h) under the Exchange Act) or liquidate or decrease any “call equivalent position” (as defined in Rule 16a-1b) of any of our securities;

∎ pledge, hypothecate or grant any security interest in any of our securities;

∎ in any other way transfer or dispose of our securities;

∎ enter into any swap, hedge or similar arrangement or agreement that transfers, in whole or in part, the economic risk of ownership of any of our securities, regardless of whether any such transaction is to be settled in securities, in cash or otherwise;

∎ submit or file, or make any demand for or exercise any right with respect to, any registration statement under the Securities Act in respect of any of our securities;

∎ effect a reverse stock split, recapitalization, share consolidation, reclassification or similar transaction affecting our outstanding common stock; or

∎ publicly announce an intention to do any of the foregoing for a period of 90 days after the date of this prospectus supplement without the prior written consent of Jefferies LLC and BofA Securities Inc.

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This restriction terminates after the close of trading of the common stock on and including the 90^th day after the date of this prospectus supplement.

Jefferies LLC and BofA Securities, Inc. may, in their sole discretion and at any time or from time to time before the termination of the 90-day period release all or any portion of the securities subject to lock-up agreements. Except for customary lock-up exceptions, including with respect to our Sales Agreement with Jefferies LLC, as described above, there are no existing agreements between the underwriters and any of our stockholders who executed a lock-up agreement, providing consent to the sale of shares prior to the expiration of the lock-up period.

Stabilization

The underwriters have advised us that they may engage in short sale transactions, stabilizing transactions, syndicate covering transactions or the imposition of penalty bids in connection with this offering. These activities may have the effect of stabilizing or maintaining the market price of our common stock at a level above that which might otherwise prevail in the open market. Establishing short sales positions may involve either “covered” short sales or “naked” short sales.

“Covered” short sales are sales made in an amount not greater than the underwriters’ option to purchase additional shares of our common stock in this offering. The underwriters may close out any covered short position by either exercising their option to purchase additional shares of our common stock or purchasing shares of our common stock in the open market. In determining the source of shares to close out the covered short position, the underwriters will consider, among other things, the price of shares available for purchase in the open market as compared to the price at which they may purchase shares through the option to purchase additional shares.

“Naked” short sales are sales in excess of the option to purchase additional shares of our common stock. The underwriters must close out any naked short position by purchasing shares in the open market. A naked short position is more likely to be created if the underwriters are concerned that there may be downward pressure on the price of the shares of our common stock in the open market after pricing that could adversely affect investors who purchase in this offering.

A stabilizing bid is a bid for the purchase of shares of common stock on behalf of the underwriters for the purpose of fixing or maintaining the price of the common stock. A syndicate covering transaction is the bid for or the purchase of shares of common stock on behalf of the underwriters to reduce a short position incurred by the underwriters in connection with the offering. Similar to other purchase transactions, the underwriter’s purchases to cover the syndicate short sales may have the effect of raising or maintaining the market price of our common stock or preventing or retarding a decline in the market price of our common stock. As a result, the price of our common stock may be higher than the price that might otherwise exist in the open market. A penalty bid is an arrangement permitting the underwriters to reclaim the selling concession otherwise accruing to a syndicate member in connection with the offering if the common stock originally sold by such syndicate member are purchased in a syndicate covering transaction and therefore have not been effectively placed by such syndicate member.

Neither we, nor any of the underwriters make any representation or prediction as to the direction or magnitude of any effect that the transactions described above may have on the price of our common stock. The underwriters are not obligated to engage in these activities and, if commenced, any of the activities may be discontinued at any time.

The underwriters may also engage in passive market making transactions in our common stock on Nasdaq in accordance with Rule 103 of Regulation M during a period before the commencement of offers or sales of shares of our common stock in this offering and extending through the completion of distribution. A passive market maker must display its bid at a price not in excess of the highest independent bid of that security. However, if all independent bids are lowered below the passive market maker’s bid, that bid must then be lowered when specified purchase limits are exceeded.

Electronic Distribution

A prospectus supplement in electronic format may be made available by e-mail or on the web sites or through online services maintained by one or more of the underwriters or their respective affiliates. In those cases, prospective investors may view offering terms online and may be allowed to place orders online. The underwriters may agree with

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us to allocate a specific number of shares of common stock for sale to online brokerage account holders. Any such allocation for online distributions will be made by the underwriters on the same basis as other allocations. Other than this prospectus supplement and the accompanying prospectus in electronic format, the information on the underwriters’ web sites and any information contained in any other web site maintained by any of the underwriters is not part of this prospectus supplement or the accompanying prospectus, has not been approved and/or endorsed by us or the underwriters and should not be relied upon by investors.

Other Activities and Relationships

The underwriters and certain of their respective affiliates are full service financial institutions engaged in various activities, which may include securities trading, commercial and investment banking, financial advisory, investment management, investment research, principal investment, hedging, financing and brokerage activities. The underwriters and certain of their respective affiliates have, from time to time, performed, and may in the future perform, various commercial and investment banking and financial advisory services for us and our affiliates, for which they received or will receive customary fees and expenses. For example, Jefferies LLC is the sales agent under our Sales Agreement, pursuant to which we may offer and sell through Jefferies LLC our common stock from time to time in “at the market” offerings. In addition, in October 2024, Jefferies LLC served as the placement agent for a private placement of our securities, for which it received fees and expenses.

Pursuant to a letter agreement, we have granted Jefferies LLC a right of first refusal to act as sole deal manager and solicitation agent in connection with any tender or exchange offer for, or consent solicitation with respect to, debt securities, and to act as our exclusive financial advisor in connection with certain mergers, acquisitions, consolidations, dispositions and restructuring transactions. We have also granted Jefferies LLC a right of first refusal, for a period ending 12 months from the date of the termination of the letter agreement, to act as lead book-running manager, lead global coordinator, lead placement agent and lead arranger for the sale of securities by us.

In the ordinary course of their various business activities, the underwriters and certain of their respective affiliates may make or hold a broad array of investments and actively trade debt and equity securities (or related derivative securities) and financial instruments (including bank loans) for their own account and for the accounts of their customers, and such investment and securities activities may involve securities and/or instruments issued by us and our affiliates. If the underwriters or their respective affiliates have a lending relationship with us, they routinely hedge their credit exposure to us consistent with their customary risk management policies. The underwriters and their respective affiliates may hedge such exposure by entering into transactions which consist of either the purchase of credit default swaps or the creation of short positions in our securities or the securities of our affiliates, including potentially the securities offered hereby. Any such short positions could adversely affect future trading prices of the securities offered hereby. The underwriters and certain of their respective affiliates may also communicate independent investment recommendations, market color or trading ideas and/or publish or express independent research views in respect of such securities or instruments and may at any time hold, or recommend to clients that they acquire, long and/or short positions in such securities and instruments.

Disclaimers About Non-U.S. Jurisdictions

European Economic Area

In relation to each Member State of the European Economic Area (each a Relevant State), no securities have been offered or will be offered pursuant to the offering to the public in that Relevant State prior to the publication of a prospectus in relation to the securities which has been approved by the competent authority in that Relevant State or, where appropriate, approved in another Relevant State and notified to the competent authority in that Relevant State, all in accordance with the Prospectus Regulation, except that the securities may be offered to the public in that Relevant State at any time:

(i) to any legal entity which is a qualified investor as defined under Article 2 of the Prospectus Regulation;

(ii) to fewer than 150 natural or legal persons (other than qualified investors as defined under Article 2 of the Prospectus Regulation), subject to obtaining the prior consent of representatives for any such offer; or

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(iii) in any other circumstances falling within Article 1(4) of the Prospectus Regulation, provided that no such offer of the securities shall require us or any of the representatives to publish a prospectus pursuant to Article 3 of the Prospectus Regulation or supplement a prospectus pursuant to Article 23 of the Prospectus Regulation.

For the purposes of this provision, the expression an “offer to the public” in relation to the securities in any Relevant State means the communication in any form and by any means of sufficient information on the terms of the offer and any securities to be offered so as to enable an investor to decide to purchase or subscribe for any securities, and the expression “Prospectus Regulation” means Regulation (EU) 2017/1129.

United Kingdom

No securities have been offered or will be offered pursuant to the offering to the public in the United Kingdom prior to the publication of a prospectus in relation to the securities which has been approved by the Financial Conduct Authority, except that the securities may be offered to the public in the United Kingdom at any time:

(i) to any legal entity which is a qualified investor as defined under Article 2 of the UK Prospectus Regulation;

(ii) to fewer than 150 natural or legal persons (other than qualified investors as defined under Article 2 of the UK Prospectus Regulation), subject to obtaining the prior consent of the representatives for any such offer; or

(iii) in any other circumstances falling within Section 86 of the FSMA,

provided that no such offer of the securities shall require the Issuer or any Manager to publish a prospectus pursuant to Section 85 of the FSMA or supplement a prospectus pursuant to Article 23 of the UK Prospectus Regulation.

For the purposes of this provision, the expression an “offer to the public” in relation to the securities in the United Kingdom means the communication in any form and by any means of sufficient information on the terms of the offer and any securities to be offered so as to enable an investor to decide to purchase or subscribe for any securities and the expression “UK Prospectus Regulation” means Regulation (EU) 2017/1129 as it forms part of domestic law by virtue of the European Union (Withdrawal) Act 2018.

In addition, in the United Kingdom, this prospectus supplement is being distributed only to, and is directed only at, and any offer subsequently made may only be directed at persons who are “qualified investors” (as defined in Article 2 of the UK Prospectus Regulation) (i) who have professional experience in matters relating to investments and who qualify as investment professionals within the meaning of Article 19(5) of the Financial Services and Markets Act 2000 (Financial Promotion) Order 2005, as amended, or the Financial Promotion Order; and/or (ii) who are high net worth companies (or persons to whom it may otherwise be lawfully communicated) falling within Article 49(2)(a) to (d) of the Financial Promotion Order (all such persons together being referred to as “relevant persons”) or otherwise in circumstances which have not resulted and will not result in an offer to the public of the securities in the United Kingdom within the meaning of the FSMA.

Canada

(A) Resale Restrictions

The distribution of securities in Canada is being made only in the provinces of Ontario, Quebec, Alberta, British Columbia, Manitoba, New Brunswick and Nova Scotia on a private placement basis exempt from the requirement that we prepare and file a prospectus with the securities regulatory authorities in each province where trades of these securities are made. Any resale of the securities in Canada must be made under applicable securities laws which may vary depending on the relevant jurisdiction, and which may require resales to be made under available statutory exemptions or under a discretionary exemption granted by the applicable Canadian securities regulatory authority. Purchasers are advised to seek legal advice prior to any resale of the securities.

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(B) Representations of Canadian Purchasers

By purchasing securities in Canada and accepting delivery of a purchase confirmation, a purchaser is representing to us and the dealer from whom the purchase confirmation is received that:

∎ the purchaser is entitled under applicable provincial securities laws to purchase the securities without the benefit of a prospectus qualified under those securities laws as it is an “accredited investor” as defined under National Instrument 45-106 - Prospectus Exemptions or Section 73.3(1) of the Securities Act (Ontario), as applicable,

∎ the purchaser is a “permitted client” as defined in National Instrument 31-103—Registration Requirements, Exemptions and Ongoing Registrant Obligations,

∎ where required by law, the purchaser is purchasing as principal and not as agent, and

∎ the purchaser has reviewed the text above under Resale Restrictions.

(C) Conflicts of Interest

Canadian purchasers are hereby notified that certain of the underwriters are relying on the exemption set out in section 3A.3 or 3A.4, if applicable, of National Instrument 33-105—Underwriting Conflicts from having to provide certain conflict of interest disclosure in this prospectus supplement.

(D) Statutory Rights of Action

Securities legislation in certain provinces or territories of Canada may provide a purchaser with remedies for rescission or damages if the prospectus (including any amendment thereto) such as this prospectus supplement contains a misrepresentation, provided that the remedies for rescission or damages are exercised by the purchaser within the time limit prescribed by the securities legislation of the purchaser’s province or territory. The purchaser of these securities in Canada should refer to any applicable provisions of the securities legislation of the purchaser’s province or territory for particulars of these rights or consult with a legal advisor.

(E) Enforcement of Legal Rights

All of our directors and officers as well as the experts named herein may be located outside of Canada and, as a result, it may not be possible for Canadian purchasers to effect service of process within Canada upon us or those persons. All or a substantial portion of our assets and the assets of those persons may be located outside of Canada and, as a result, it may not be possible to satisfy a judgment against us or those persons in Canada or to enforce a judgment obtained in Canadian courts against us or those persons outside of Canada.

(F) Taxation and Eligibility for Investment

Canadian purchasers of securities should consult their own legal and tax advisors with respect to the tax consequences of an investment in the securities in their particular circumstances and about the eligibility of the securities for investment by the purchaser under relevant Canadian legislation.

Australia

This prospectus supplement is not a disclosure document for the purposes of Australia’s Corporations Act 2001 (Cth) of Australia (the Corporations Act) has not been lodged with the Australian Securities & Investments Commission and is only directed to the categories of exempt persons set out below. Accordingly, if you receive this prospectus supplement in Australia:

You confirm and warrant that you are either:

∎ a “sophisticated investor” under section 708(8)(a) or (b) of the Corporations Act;

∎ a “sophisticated investor” under section 708(8)(c) or (d) of the Corporations Act and that you have provided an accountant’s certificate to us which complies with the requirements of section 708(8)(c)(i) or (ii) of the Corporations Act and related regulations before the offer has been made;

∎ a person associated with us under Section 708(12) of the Corporations Act; or

∎ a “professional investor” within the meaning of section 708(11)(a) or (b) of the Corporations Act.

To the extent that you are unable to confirm or warrant that you are an exempt sophisticated investor, associated person or professional investor under the Corporations Act any offer made to you under this prospectus supplement is void and incapable of acceptance.

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You warrant and agree that you will not offer any of the securities issued to you pursuant to this prospectus supplement for resale in Australia within 12 months of those securities being issued unless any such resale offer is exempt from the requirement to issue a disclosure document under section 708 of the Corporations Act.

Hong Kong

No securities have been offered or sold, and no securities may be offered or sold, in Hong Kong, by means of any document, other than to persons whose ordinary business is to buy or sell shares or debentures, whether as principal or agent; or to “professional investors” as defined in the Securities and Futures Ordinance (Cap. 571) of Hong Kong (SFO) and any rules made under that Ordinance; or in other circumstances which do not result in the document being a “prospectus” as defined in the Companies Ordinance (Cap. 32) of Hong Kong (CO) or which do not constitute an offer or invitation to the public for the purpose of the CO or the SFO. No document, invitation or advertisement relating to the securities has been issued or may be issued or may be in the possession of any person for the purpose of issue (in each case whether in Hong Kong or elsewhere), which is directed at, or the contents of which are likely to be accessed or read by, the public of Hong Kong (except if permitted under the securities laws of Hong Kong) other than with respect to securities which are or are intended to be disposed of only to persons outside Hong Kong or only to “professional investors” as defined in the SFO and any rules made under that Ordinance.

This prospectus supplement has not been registered with the Registrar of Companies in Hong Kong. Accordingly, this prospectus supplement may not be issued, circulated or distributed in Hong Kong, and the securities may not be offered for subscription to members of the public in Hong Kong. Each person acquiring the securities will be required, and is deemed by the acquisition of the securities, to confirm that he is aware of the restriction on offers of the securities described in this prospectus supplement and the relevant offering documents and that he is not acquiring, and has not been offered any securities in circumstances that contravene any such restrictions.

Israel

This prospectus supplement does not constitute a prospectus under the Israeli Securities Law, 5728-1968 (the Securities Law) and has not been filed with or approved by the Israel Securities Authority. In Israel, this prospectus supplement is being distributed only to, and is directed only at, and any offer of the securities is directed only at, (i) a limited number of persons in accordance with the Israeli Securities Law and (ii) investors listed in the first addendum (the Israel Addendum) to the Israeli Securities Law, consisting primarily of joint investment in trust funds, provident funds, insurance companies, banks, portfolio managers, investment advisors, members of the Tel Aviv Stock Exchange, underwriters, venture capital funds, entities with equity in excess of NIS 50 million and “qualified individuals,” each as defined in the Israel Addendum (as it may be amended from time to time), collectively referred to as qualified investors (in each case, purchasing for their own account or, where permitted under the Israel Addendum, for the accounts of their clients who are investors listed in the Israel Addendum). Qualified investors are required to submit written confirmation that they fall within the scope of the Israel Addendum, are aware of the meaning of same and agree to it.

Japan

The offering has not been and will not be registered under the Financial Instruments and Exchange Law of Japan (Law No. 25 of 1948 of Japan, as amended) (FIEL) and the underwriters will not offer or sell any securities, directly or indirectly, in Japan or to, or for the benefit of, any resident of Japan (which term as used herein means any person resident in Japan, including any corporation or other entity organized under the laws of Japan), or to others for re-offering or resale, directly or indirectly, in Japan or to, or for the benefit of, any resident of Japan, except pursuant to an exemption from the registration requirements of, and otherwise in compliance with, the FIEL and any other applicable laws, regulations and ministerial guidelines of Japan.

Singapore

This prospectus supplement has not been and will not be lodged or registered as a prospectus with the Monetary Authority of Singapore. Accordingly, this prospectus supplement and any other document or material in connection with the offer or sale, or invitation for subscription or purchase, of the securities may not be circulated or distributed, nor may the securities be offered or sold, or be made the subject of an invitation for subscription or purchase, whether directly or indirectly, to persons in Singapore other than (i) to an institutional investor under Section 274 of the Securities and Futures Act, Chapter 289 of Singapore (SFA), (ii) to a relevant person pursuant to Section 275(1), or any person pursuant to Section 275(1A), and in accordance with the conditions specified in

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Section 275, of the SFA, or (iii) otherwise pursuant to, and in accordance with the conditions of, any other applicable provision of the SFA.

Where the securities are subscribed or purchased under Section 275 of the SFA by a relevant person which is:

(a) a corporation (which is not an accredited investor (as defined in Section 4A of the SFA)) the sole business of which is to hold investments and the entire share capital of which is owned by one or more individuals, each of whom is an accredited investor; or

(b) a trust (where the trustee is not an accredited investor) whose sole purpose is to hold investments and each beneficiary of the trust is an individual who is an accredited investor, securities (as defined in Section 239(1) of the SFA) of that corporation or the beneficiaries’ rights and interest (howsoever described) in that trust shall not be transferred within six months after that corporation or that trust has acquired the securities pursuant to an offer made under Section 275 of the SFA except:

(i) to an institutional investor or to a relevant person defined in Section 275(2) of the SFA, or to any person arising from an offer referred to in Section 275(1A) or Section 276(4)(i)(B) of the SFA;

(ii) where no consideration is or will be given for the transfer;

(iii) where the transfer is by operation of law;

(iv) as specified in Section 276(7) of the SFA; or

(v) as specified in Regulation 32 of the Securities and Futures (Offers of Investments) (Shares and Debentures) Regulations 2005 of Singapore.

Switzerland

This prospectus supplement is not intended to constitute an offer or solicitation to purchase or invest in the securities. The securities may not be publicly offered, directly or indirectly, in Switzerland within the meaning of the Swiss Financial Services Act (FinSA), and no application has or will be made to admit the securities to trading on any trading venue (exchange or multilateral trading facility) in Switzerland. Neither this prospectus supplement and the accompanying prospectus nor any other offering or marketing material relating to the securities constitutes a prospectus pursuant to the FinSA, and neither this prospectus supplement nor any other offering or marketing material relating to the securities may be publicly distributed or otherwise made publicly available in Switzerland.

Neither this prospectus supplement nor any other offering or marketing material relating to the offering, us or the securities have been or will be filed with or approved by any Swiss regulatory authority. In particular, this prospectus supplement will not be filed with, and the offer of securities will not be supervised by, the Swiss Financial Market Supervisory Authority (FINMA) and the offer of securities has not been and will not be authorized under the Swiss Federal Act on Collective Investment Schemes (CISA). The investor protection afforded to acquirers of interests in collective investment schemes under the CISA does not extend to acquirers of securities.

Dubai International Financial Centre

This document relates to an Exempt Offer in accordance with the Markets Rules of the Dubai Financial Services Authority. This document is intended for distribution only to Persons of a type specified in those rules to whom Exempt Offers can be made. It must not be delivered to, or relied on by, any other Person. The Dubai Financial Services Authority has no responsibility for reviewing or verifying any documents in connection with Exempt Offers. The Dubai Financial Services Authority has not approved this document nor taken steps to verify the information set out in it, and has no responsibility for it. The securities to which this document relates may be illiquid and/or subject to restrictions on their resale. Prospective purchasers of the securities offered should conduct their own due diligence on the securities. If you do not understand the contents of this document you should consult an authorized financial adviser.

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LEGAL MATTERS

The validity of the shares of common stock and pre-funded warrants offered hereby will be passed upon for us by Goodwin Procter LLP, Boston, Massachusetts. Cooley LLP, New York, New York, is acting as counsel for the underwriters in connection with this offering.

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EXPERTS

The consolidated financial statements of Inhibikase Therapeutics, Inc. and Subsidiary for the two years ended December 31, 2024, have been audited by CohnReznick LLP, independent registered public accounting firm, as set forth in their report thereon appearing in Inhibikase Therapeutics, Inc. and Subsidiary Annual Report on Form 10-K for the year ended December 31, 2024, and incorporated by reference herein. Such consolidated financial statements are incorporated by reference herein in reliance upon such report, given on the authority of such firm as experts in accounting and auditing.

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WHERE YOU CAN FIND MORE INFORMATION

We file annual, quarterly and current reports, proxy statements and other information with the SEC. Our SEC filings are available to the public over the Internet at the SEC’s website at www.sec.gov and on our investor website at http:www.inhibikase.com. Information contained on our website is not incorporated by reference into this prospectus supplement or the accompanying prospectus, and you should not consider any information on, or that can be accessed from, our website as part of this prospectus supplement or the accompanying prospectus.

This prospectus supplement is part of a registration statement that we have filed with the SEC. Certain information in the registration statement has been omitted from this prospectus supplement in accordance with the rules of the SEC. For more detail about us and any securities that may be offered by this prospectus supplement, you may examine the registration statement of which this prospectus supplement forms a part, including its exhibits and schedules. Statements contained in this prospectus supplement and the accompanying prospectus as to the contents of any contract or other document are not necessarily complete, and in each instance we refer you to the copy of the contract or document filed as an exhibit to the registration statement, each such statement being qualified in all respects by such reference.

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INCORPORATION OF CERTAIN INFORMATION BY REFERENCE

The SEC allows us to incorporate by reference in this prospectus supplement much of the information we file with the SEC, which means that we can disclose important information to you by referring you to those publicly available documents. The information that we incorporate by reference in this prospectus supplement and the accompanying prospectus is considered to be part of this prospectus supplement. Because we are incorporating by reference future filings with the SEC, this prospectus supplement is continually updated and those future filings may modify or supersede some of the information included or incorporated in this prospectus supplement. This means that you must look at all of the SEC filings that we incorporate by reference to determine if any of the statements in this prospectus supplement or in any document previously incorporated by reference have been modified or superseded. This prospectus supplement incorporates by reference the documents listed below and any future filings we make with the SEC under Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act, except as to any portion of any future report or document that is not deemed filed under such provisions until the offering of the securities offered hereby is terminated or completed:

∎ Annual Report on Form 10-K for the fiscal year ended December 31, 2024, filed with the SEC on March  27, 2025, as amended by a Form 10-K/A, filed with the SEC on April 25, 2025;

∎ Quarterly Reports on Form 10-Q for the quarters ended March 31, 2025, June 30, 2025 and September 30, 2025, filed with the SEC on May  14, 2025, August  14, 2025 and November 14, 2025, respectively;

∎ Current Reports on Form 8-K filed with the SEC on January 6, 2025, January  29, 2025, February  18, 2025, February  24, 2025, April  14, 2025, June  30, 2025 and November 20, 2025; and

∎ The description of our common stock contained in our Registration Statement on Form 8-A (File No. 001-39676), filed with the SEC under Section 12(b) of the Exchange Act, filed with the SEC on October 29, 2020, including any amendments or reports filed for the purpose of updating such description.

You may request a copy of these filings, at no cost, by writing or telephoning us at the following address or telephone number:

Inhibikase Therapeutics, Inc.

1000 N. West Street, Suite 1200

Wilmington, Delaware 19801

Attn: Investor Relations

(302) 295-3800

You may also access these documents, free of charge on the SEC’s website at www.sec.gov or on our website at www.inhibikase.com. Information contained on our website is not incorporated by reference into this prospectus supplement or the accompanying prospectus, and you should not consider any information on, or that can be accessed from, our website as part of this prospectus supplement or the accompanying prospectus.

Notwithstanding the foregoing, unless specifically stated to the contrary, information that we furnish (and that is not deemed “filed” with the SEC) under Items 2.02 and 7.01 of any Current Report on Form 8-K, including the related exhibits under Item 9.01, is not incorporated by reference into this prospectus supplement or the accompanying prospectus.

In accordance with Rule 412 of the Securities Act, any statement contained in a document incorporated by reference herein shall be deemed modified or superseded to the extent that a statement contained herein or in any other subsequently filed document which also is or is deemed to be incorporated by reference herein modifies or supersedes such statement.

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PROSPECTUS

$300,000,000

Common Stock

Preferred Stock

Debt Securities

Warrants

Units

We may from time to time issue, in one or more series or classes, up to $300,000,000 in aggregate principal amount of our common stock, preferred stock, debt securities, warrants and/or units, in any combination, together or separately, in one or more offerings in amounts, at prices and on the terms that we will determine at the time of the offering and which will be set forth in a prospectus supplement to this prospectus and any related free writing prospectus. We may offer these securities separately or together in units. Each time we sell securities described herein, we will specify in the applicable accompanying prospectus supplement the terms of the securities being offered. We may sell these securities to or through underwriters or dealers and also to other purchasers or through agents. We will set forth the names of any underwriters or agents, and any fees, conversions or discount arrangements, in the applicable accompanying prospectus supplement. We may not sell any securities under this prospectus without delivery of the applicable prospectus supplement.

You should read this document and any prospectus supplement or amendment carefully before you invest in our securities.

Our common stock is listed on the Nasdaq Capital Market under the symbol “IKT.” On June 18, 2025, the closing price for our common stock, as reported on the Nasdaq Capital Market, was $1.70 per share.

Investing in our securities involves a high degree of risk. You should review carefully the risks and uncertainties referenced under the heading “Risk Factors” contained in this prospectus beginning on page 2 and any applicable prospectus supplement, and under similar headings in the other documents that are incorporated by reference into this prospectus.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

The date of this Prospectus is June 27, 2025.

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TABLE OF CONTENTS

		PAGE
ABOUT THIS PROSPECTUS			1
RISK FACTORS			2
CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS			3
THE COMPANY			5
USE OF PROCEEDS			7
SECURITIES THAT MAY BE OFFERED			8
DESCRIPTION OF CAPITAL STOCK			9
DESCRIPTION OF DEBT SECURITIES			14
DESCRIPTION OF WARRANTS			20
DESCRIPTION OF UNITS			21
PLAN OF DISTRIBUTION			24
LEGAL MATTERS			27
EXPERTS			28
WHERE YOU CAN FIND MORE INFORMATION			29
INCORPORATION BY REFERENCE			30

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ABOUT THIS PROSPECTUS

This prospectus is part of a shelf registration statement on Form S-3 that we filed with the Securities and Exchange Commission (the “SEC”) under the Securities Act of 1933, as amended (the “Securities Act”), using a “shelf” registration process.

Under this shelf registration process, we may from time to time sell any combination of the securities described in this prospectus in one or more offerings for an aggregate offering amount of up to $300,000,000. This prospectus provides you with a general description of the securities we may offer. Each time we sell securities, we will provide one or more prospectus supplements that will contain specific information about the terms of the offering. The applicable prospectus supplement may also add, update or change information contained in this prospectus. This prospectus, together with any accompanying prospectus supplement, contains important information you should know before investing in our securities, including important information about us and the securities being offered. You should read both this prospectus, any applicable accompanying prospectus supplement, and any related free writing prospectus, together with the additional information described under the headings “Where You Can Find More Information” and “Incorporation by Reference” beginning on page 29 of this prospectus.

You should rely only on the information contained in or incorporated by reference in this prospectus, any accompanying prospectus supplement or in any related free writing prospectus filed by us with the SEC. We have not authorized anyone to provide you with different information. This prospectus does not constitute an offer to sell or the solicitation of an offer to buy any securities other than the securities described in any accompanying prospectus supplement or an offer to sell or the solicitation of an offer to buy such securities in any circumstances in which such offer or solicitation is unlawful. You should assume that the information appearing in this prospectus, any accompanying prospectus supplement, the documents incorporated by reference and any related free writing prospectus is accurate only as of their respective dates. Our business, financial condition, results of operations and prospects may have changed materially since those dates. This prospectus, any applicable prospectus supplement and the information incorporated herein or therein by reference contains market data, industry statistics and other data that have been obtained or compiled from information made available by independent third parties. We are responsible for all of the disclosures contained in this prospectus, and we believe that these sources are reliable; however, we have not independently verified the information contained in such publications.

THIS PROSPECTUS MAY NOT BE USED TO OFFER AND SELL SECURITIES UNLESS IT IS ACCOMPANIED BY AN ADDITIONAL PROSPECTUS OR A PROSPECTUS SUPPLEMENT.

As used in this prospectus, unless the context suggests otherwise, all references to “us,” “our,” “Inhibikase,” “we,” the “Company” and similar designations refer to Inhibikase Therapeutics, Inc.

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RISK FACTORS

Investing in our securities involves a high degree of risk. You should carefully consider the risks set forth in our filings with the SEC that are described in the documents incorporated by reference in this prospectus and any applicable prospectus supplement, as well as other information we include or incorporate by reference into this prospectus and any applicable prospectus supplement, before making an investment decision. Our business, financial condition or results of operations could be materially adversely affected by the materialization of any of these risks. The trading price of our securities could decline due to the materialization of any of these risks, and you may lose all or part of your investment. This prospectus and the documents incorporated herein by reference also contain forward-looking statements that involve risks and uncertainties. Actual results could differ materially from those anticipated in these forward-looking statements as a result of certain factors, including the risks described in the documents incorporated herein by reference, including our most recent Annual Report on Form 10-K, as revised or supplemented by our subsequent Quarterly Reports on Form 10-Q or our Current Reports on Form 8-K, as applicable, and the other documents we file with the SEC that are deemed incorporated by reference into this prospectus. Additional risks and uncertainties not presently known to us or that we currently deem immaterial may also adversely affect our operations.

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CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS

This prospectus, any applicable prospectus supplement, any related free writing prospectus and the documents that we incorporate by reference herein or therein contain forward-looking statements within the meaning of Section 27A of the Securities Act and Section 21E of the Securities Exchange Act of 1934, as amended (the “Exchange Act”). Any statements about our expectations, beliefs, plans, objectives, assumptions or future events or performance are not historical facts and may be forward-looking. These statements are often, but are not always, made through the use of words or phrases such as “anticipates,” “expects,” “intends,” “plans,” “predicts,” “believes,” “seeks,” “estimates,” “may,” “will,” “should,” “would,” “could,” “potential,” “continue,” “ongoing,” and similar expressions and variations or negatives of these words.

Accordingly, these statements involve estimates, assumptions, risks and uncertainties which could cause actual results to differ materially from those expressed in them. Any forward-looking statements are qualified in their entirety by reference to the factors discussed throughout this prospectus, and in particular those factors referenced in the section “Risk Factors.”

This prospectus contains forward-looking statements that are based on our management’s belief and assumptions and on information currently available to our management. These statements relate to future events or our future financial performance, and involve known and unknown risks, uncertainties and other factors that may cause our actual results, levels of activity, performance or achievements to be materially different from any future results, levels of activity, performance or achievements expressed or implied by these forward-looking statements. Forward-looking statements include, but are not limited to, statements about:

∎ the success, cost and timing of our product development activities and clinical trials, including statements regarding the timing of initiation and completion of studies or trials and related preparatory work, the period during which the results of the trials will become available, and our research and development programs;

∎ our ability to initiate a Phase 2b trial in pulmonary arterial hypertension;

∎ our ability to successfully complete any future clinical trial;

∎ our ability to successfully manufacture our product candidates for future clinical trials or for commercial use, if approved;

∎ our ability to obtain and maintain regulatory approval, if obtained, for any product candidates;

∎ the success of competing therapies that are or become available;

∎ our ability to obtain funding for our operations, including funding necessary to complete further development and commercialization of our product candidates;

∎ the commercialization of our product candidates, if approved;

∎ future agreements with third parties in connection with the commercialization of our product candidates and any other approved product;

∎ the size and growth potential of the markets for our product candidates, if approved, and our ability to serve those markets;

∎ the rate and degree of market acceptance of our product candidates, if approved;

∎ regulatory developments in the United States and foreign countries;

∎ our ability to contract with third-party suppliers and manufacturers and their ability to perform adequately;

∎ our ability to attract and retain key scientific or management personnel;

∎ the accuracy of our estimates regarding expenses, future revenue, capital requirements and needs for additional financing;

∎ the impact of laws and regulations; and our expectations regarding our ability to obtain and maintain intellectual property protection for our product candidates;

∎ the impact of trade restrictions such as sanctions, tariffs, reciprocal and retaliatory tariffs, and other tariff-related measures; regulatory requirements, legal actions, or enforcement; and inflation rates on our business, financial condition and results of operations;

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∎ the potential for another pandemic, epidemic or outbreak of an infectious disease to disrupt our business plans, product development activities, ongoing clinical trials, including the timing and enrollment of patients, the health of our employees and the strength of our supply chain; and

∎ our expectations regarding our ability to obtain and maintain intellectual property protection for our product candidates.

These forward-looking statements are neither promises nor guarantees of future performance due to a variety of risks and uncertainties, many of which are beyond our control, which could cause actual results to differ materially from those indicated by these forward-looking statements, including the risks outlined under the heading “Risk Factors” contained in this prospectus and any related free writing prospectus, and in any other documents incorporated herein or therein (including in our most recent Annual Report on Form 10-K, subsequent Quarterly Reports on Form 10-Q and other filings we make with the SEC pursuant to Section 13(a), 13(c), 14 or 15(d) of the Exchange Act).

The forward-looking statements in this prospectus and the documents incorporated by reference represent our views as of their respective dates. We anticipate that subsequent events and developments will cause our views to change. However, while we may elect to update these forward-looking statements at some point in the future, we assume no obligation to update or revise any forward-looking statements except to the extent required by applicable law. You should, therefore, not rely on these forward-looking statements as representing our views as of any date subsequent to the dates on which they were made.

This prospectus and the documents incorporated by reference also contain estimates, projections and other information concerning our industry, our business, and the markets for certain diseases, including data regarding the estimated size of those markets, and the incidence and prevalence of certain medical conditions. Information that is based on estimates, forecasts, projections, market research or similar methodologies is inherently subject to uncertainties and actual events or circumstances may differ materially from events and circumstances reflected in this information. Unless otherwise expressly stated, we obtained this industry, business, market and other data from reports, research surveys, studies and similar data prepared by market research firms and other third parties, industry, medical and general publications, government data and similar sources.

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THE COMPANY

We are a clinical-stage pharmaceutical company developing therapeutics to modify the course of cardiopulmonary diseases namely, Pulmonary Arterial Hypertension (“PAH”) which is an orphan indication. Our lead product candidate is IKT-001, a prodrug of imatinib mesylate, which may impact the underlying pathophysiology of PAH from aberrant signaling through type III receptor tyrosine kinases including platelet derived growth factor receptors, c-KIT and possibly colony stimulating factor 1 receptor and Abelson tyrosine kinase (“ABL”). We have completed non-human primate safety studies and a bioequivalence clinical trial in healthy volunteers to determine the doses of IKT-001 that are equivalent to established efficacious doses of imatinib mesylate.

IKT-001

IKT-001 emerged from our medicinal chemistry program that aimed to develop improvements to drugs that inhibit ABL and type III receptor tyrosine kinases. IKT-001, a prodrug of imatinib mesylate, was designed to modify structural elements of the parent molecule that might play a role in the gastrointestinal (“GI”) side effects commonly observed with oral imatinib mesylate. A three-part dose finding/dose equivalence study in 66 healthy volunteers was completed with IKT-001 in 2023. The study was designed to establish that IKT-001 is stable in the gut and is rapidly and completely bio-converted into imatinib in the blood. In addition, this study evaluated the pharmacokinetics of imatinib delivered as IKT-001 to determine the dose relationship between IKT-001 and imatinib mesylate. Based on this study bioequivalence was established with a 300 mg dose of IKT-001 bioequivalent to a dose of 230 mg of imatinib mesylate while a 500 mg dose of IKT-001 was bioequivalent to a dose of 383 mg of imatinib mesylate. Based on target kinase inhibition in vitro (IC50s), exposures at these doses are adequate to cover the targets systemically and are similar to the doses of imatinib mesylate used in the Phase 3 IMPRES trial in PAH.

On January 19, 2024, we met with the Food and Drug Administration (“FDA”) Hematological Malignancy Review Team (“Review Team”) in a Pre-New Drug Application (“pre-NDA”), meeting to discuss our bioequivalence studies of IKT-001 and its path to approval. All questions were addressed and summarized in official meeting minutes issued by the FDA on February 12, 2024. During the meeting, we inquired whether additional clinical studies would be needed to seek approval and discussed manufacturing and quality control requirements for approval. The Review Team acknowledged that the 505(b)(2) pathway appeared to be the appropriate pathway for approval of IKT-001.

PAH

PAH is a rare disease of the pulmonary microvasculature found in 15 to 50 persons per million within the United States and Europe. The global PAH market size was valued at $7.66 billion in 2023 and is estimated to grow at a compound annual growth rate of over 5% between 2024 and 2030. Most of the treatments that constitute the standard of care (e.g. ERAs, PDE5is, prostacyclins) primarily act as vasodilators. In 2024, sotatercept was approved for the treatment of PAH on top of standard-of-care. Sotatercept is a recombinant fusion protein that acts as a trap for transforming growth factor-beta superfamily ligands, including activin A and bone morphogenetic protein 9. These ligands may play a role in the development and progression of PAH by promoting excessive cell proliferation and fibrosis.

The success of sotatercept has created renewed enthusiasm around the anti-proliferative pathways in PAH. As previously mentioned, imatinib inhibits type III receptor tyrosine kinases and through these pathways inhibits platelet-derived growth factor receptor and c-KIT tyrosine kinase activity. These pathways are thought to be involved in excessive vascular cell proliferation and migration of mast cells and other hematopoietic stem cells that contribute to pathologic vascular remodeling. Through these targets imatinib may inhibit vascular smooth muscle cell proliferation and fibrosis which may provide an alternate pathway for disease modification in PAH.

The first reports of the use of imatinib in PAH were published in 2005 and 2006. A Phase 2, randomized control trial, was subsequently conducted showing clinical benefit of imatinib in PAH. In 2013, the outcome of a Phase 3 trial (IMPRES) evaluating imatinib mesylate as a treatment for PAH was reported. This study demonstrated that imatinib improved multiple efficacy parameters including 6 minute walk distance which is the primary endpoint in most PAH registration studies. Unfortunately, there was a high adverse event rate particularly related to GI side effects in the imatinib arm as well as a high discontinuation rate.

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We believe that IKT-001 will have an improved GI tolerance profile when compared to oral imatinib mesylate, which may allow for improved adherence at efficacious doses. This prompted us to file a pre-IND (“PIND”) meeting request to discuss the application of IKT-001 as a potential disease-modifying treatment for PAH. To evaluate this further, we met with the FDA Division of Cardiology and Nephrology in a PIND meeting to discuss our plan to utilize IKT-001 in a Phase 2b efficacy, safety and tolerability study in PAH. At the meeting, the FDA confirmed that IKT-001 would be viewed as a New Molecular Entity (“NME”) and that the appropriate path for approval remained to be the 505(b)(2) statute. This opens up the possibility of IKT-001 being granted NME status and market exclusivity on approval. The IND was filed with the FDA on August 9, 2024 and we were cleared to initiate a Phase 2b trial on September 9, 2024. We have had discussions with the FDA regarding Orphan Drug Designation (“ODD”) for delivery of imatinib by IKT-001 for PAH and plan to apply for ODD once the required pre-clinical studies are complete.

Recently, a contemporary study of imatinib in PAH was published in the American Journal of Respiratory and Critical Care Medicine. This study was an open label, single arm, four (4) center study with seventeen (17) patients of imatinib in WHO Group 1 PAH population and notably included continuous hemodynamic monitoring via a remote monitoring device. In this study there were no discontinuations due to imatinib intolerance or side effects. Importantly, imatinib reduced mean pulmonary artery pressure, total pulmonary resistance and night heart rate, all of which remained below baseline up to 40 days following imatinib withdrawal. Acknowledging the limitations of cross study comparisons and the small size of the study, we believe this recent study supports our thesis that systemic exposure of imatinib can be well tolerated and provide strong efficacy to patients suffering from PAH.

We currently have commercialization rights to IKT-001 and patent protection in the United States until 2033 for IKT-001 with upcoming patent application filings potentially extending patent protection for certain methods of treatment using IKT-001 until 2045.

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USE OF PROCEEDS

We will retain broad discretion over the use of the net proceeds from the sale of the securities offered hereby. Except as described in any applicable prospectus supplement or in any free writing prospectuses that we may authorize to be provided to you in connection with a specific offering, we currently intend to use the net proceeds from the sale of the securities covered by this prospectus for general corporate purposes, which may include, without limitation to, working capital, capital expenditures, business development and research and development expenditures and acquisitions of new technologies or businesses. The precise amount, use and timing of the application of such proceeds will depend upon our funding requirements and the availability and cost of other capital. Additional information on the use of net proceeds from an offering of securities covered by this prospectus may be set forth in the prospectus supplement relating to the specific offering.

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SECURITIES THAT MAY BE OFFERED

We may offer shares of common or preferred stock, various series of senior or subordinated debt securities, warrants, or units consisting of combinations of the foregoing, in each case from time to time under this prospectus, together with the applicable prospectus supplement, at prices and on terms to be determined by market conditions at the time of offering. This prospectus provides you with a general description of the securities we may offer from time to time. At the time we offer a particular type or series of securities, we will provide an applicable prospectus supplement describing the specific amounts, prices and other important terms of the securities, including, to the extent applicable:

∎ designation or classification;

∎ aggregate principal amount or aggregate offering price;

∎ voting or other rights;

∎ rates and times of payment of interest, dividends or other payments, if any;

∎ liquidation preference;

∎ original issue discount, if any;

∎ maturity date, if applicable;

∎ ranking;

∎ restrictive covenants, if any;

∎ redemption, conversion, exercise, exchange, settlement or sinking fund terms, including prices or rates, if any, and, if applicable, any provisions for changes to or adjustments in such prices or rates and in the securities or other property receivable upon conversion, exercise, exchange or settlement;

∎ any securities exchange or market listing arrangements; and

∎ important U.S. federal income tax considerations, if any.

This prospectus may not be used to offer or sell securities unless accompanied by an applicable prospectus supplement. The applicable prospectus supplement may add, update or change information contained in this prospectus or in documents incorporated by reference in this prospectus. You should read the prospectus supplement related to any securities being offered.

We may sell the securities directly to or through underwriters, dealers or agents, directly to purchasers or through a combination of any of these methods of sale or as otherwise set forth below under “Plan of Distribution.” We and our underwriters, dealers or agents reserve the right to accept or reject all or part of any proposed purchase of securities. If we do offer securities through underwriters or agents, we will include in the applicable prospectus supplement (i) the names of the underwriters or agents and applicable fees, discounts and commissions to be paid to them; (ii) details regarding over-allotment options, if any; and (iii) net proceeds to us.

The following descriptions are not complete and may not contain all the information you should consider before investing in any securities we may offer hereunder; they are summarized from, and qualified by reference to, our amended and restated certificate of incorporation, second amended and restated by-laws and the other documents referred to in the descriptions, all of which are or will be publicly filed with the SEC, as applicable. See “Where You Can Find More Information.”

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DESCRIPTION OF CAPITAL STOCK

The following description of our capital stock, together with the additional information we include in any applicable prospectus supplement, summarizes the material terms and provisions of our capital stock that we may offer under this prospectus. The following description of our capital stock does not purport to be complete and is subject to, and qualified in its entirety by, our amended and restated certificate of incorporation, as amended (our “certificate of incorporation”) and our amended and restated by-laws (our “by-laws” and, together with our certificate of incorporation, our “Charter Documents”), in each case, as amended and supplemented, which are filed as exhibits to the registration statement of which this prospectus forms a part, and applicable provisions of Delaware corporate law.

Authorized Capital Stock

Our authorized capital stock consists of 500,000,000 shares of common stock, par value $0.001 per share, and 10,000,000 shares of preferred stock, par value $0.001 per share, all of which are undesignated preferred stock.

Common Stock

Dividends

Holders of our common stock are entitled to receive dividends ratably, if any, as may be declared by our board of directors out of legally available funds, subject to any preferential dividend rights of any preferred stock then outstanding.

Voting

Holders of our common stock are entitled to one vote for each share of common stock held of record for the election of directors and on all matters submitted to a vote of the stockholders. The holders of our common stock do not have any cumulative voting rights.

Our by-laws provide that, except as required by law or our Charter Documents and other than with respect to the election of a director or directors, all matters will be decided by the vote of the majority of the voting power present in person or represented by proxy at the meeting and entitled to vote on the subject matter for and against such matter. Any election of directors by stockholders shall be determined by a plurality of the voting power present in person or represented by proxy at the meeting and entitled to vote on the election of directors.

Other Rights

In the event of our dissolution, liquidation or winding up, holders of our common stock are entitled to share ratably in our net assets legally available after the payment of all our debts and other liabilities, subject to the preferential rights of any preferred stock then outstanding. The rights, preferences and privileges of holders of common stock are subject to, and may be adversely affected by, the rights of the holders of shares of any series of preferred stock that we may designate and issue in the future. Holders of our common stock have no preemptive, subscription, redemption or conversion rights and no sinking fund provisions are applicable to our common stock.

When we issue shares of common stock under this prospectus, the shares will fully be paid and nonassessable and will not have, or be subject to, any preemptive or similar rights.

Listing

Our common stock is listed on the Nasdaq Capital Market under the symbol “IKT.” On June 18, 2025, the closing price for our common stock, as reported on the Nasdaq Capital Market, was $1.70 per share.

Transfer Agent and Registrar

The transfer agent and registrar for our common stock is Equiniti Trust Company, LLC.

Undesignated Preferred Stock

Our board of directors is authorized to issue up to 10,000,000 shares of undesignated preferred stock in one or more series without stockholder approval. Our board of directors may determine the rights, preferences, privileges and restrictions, including voting rights, dividend rights, conversion rights, redemption privileges and liquidation preferences, of each series of preferred stock.

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The purpose of authorizing our board of directors to issue preferred stock in one or more series and determine the number of shares in the series and its rights and preferences is to eliminate delays associated with a stockholder vote on specific issuances. Examples of rights and preferences that the board of directors may fix are:

∎ dividend rights;

∎ dividend rates;

∎ conversion rights;

∎ voting rights;

∎ terms of redemption; and

∎ liquidation preferences.

The existence of authorized but unissued shares of preferred stock may enable our board of directors to render more difficult or to discourage an attempt to obtain control of us by means of a merger, tender offer, proxy contest or otherwise. For example, if in the due exercise of its fiduciary obligations, our board of directors were to determine that a takeover proposal is not in the best interests of us or our stockholders, our board of directors could cause shares of preferred stock to be issued without stockholder approval in one or more private offerings or other transactions that might dilute the voting or other rights of the proposed acquirer, stockholder or stockholder group. The rights of holders of our common stock described above, will be subject to, and may be adversely affected by, the rights of any preferred stock that we may designate and issue in the future. The issuance of shares of preferred stock could decrease the amount of earnings and assets available for distribution to holders of shares of common stock. The issuance may also adversely affect the rights and powers, including voting rights, of these holders and may have the effect of delaying, deterring or preventing a change in control of us.

We will incorporate by reference as an exhibit to the registration statement, which includes this prospectus, the form of any certificate of designation that describes the terms of the series of preferred stock we are offering. This description and the applicable prospectus supplement will include:

∎ the title and stated value;

∎ the number of shares authorized;

∎ the liquidation preference per share;

∎ the purchase price;

∎ the dividend rate, period and payment date, and method of calculation for dividends;

∎ whether dividends will be cumulative or non-cumulative and, if cumulative, the date from which dividends will accumulate;

∎ the procedures for any auction and remarketing, if any;

∎ the provisions for a sinking fund, if any;

∎ the provisions for redemption or repurchase, if applicable, and any restrictions on our ability to exercise those redemption and repurchase rights;

∎ any listing of the preferred stock on any securities exchange or market;

∎ whether the preferred stock will be convertible into our common stock, and, if applicable, the conversion price, or how it will be calculated, and the conversion period;

∎ whether the preferred stock will be exchangeable into debt securities, and, if applicable, the exchange price, or how it will be calculated, and the exchange period;

∎ voting rights, if any, of the preferred stock;

∎ preemptive rights, if any;

∎ restrictions on transfer, sale or other assignment, if any;

∎ whether interests in the preferred stock will be represented by depositary shares;

∎ a discussion of any material United States federal income tax considerations applicable to the preferred stock;

∎ the relative ranking and preferences of the preferred stock as to dividend rights and rights if we liquidate, dissolve or wind up our affairs;

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∎ any limitations on issuance of any class or series of preferred stock ranking senior to or on a parity with the series of preferred stock as to dividend rights and rights if we liquidate, dissolve or wind up our affairs; and

∎ any other specific terms, preferences, rights or limitations of, or restrictions on, the preferred stock.

When we issue shares of preferred stock under this prospectus, the shares will fully be paid and nonassessable and will not be subject to any preemptive or similar rights.

Antitakeover Effects of Delaware Law and Provisions of our Certificate of Incorporation and By-laws

Certain provisions of the Delaware General Corporation Law and of our certificate of incorporation and by-laws could have the effect of delaying, deferring or discouraging another party from acquiring control of us. These provisions, which are summarized below, are expected to discourage certain types of coercive takeover practices and inadequate takeover bids and, as a consequence, they might also inhibit temporary fluctuations in the market price of our common stock that often result from actual or rumored hostile takeover attempts. These provisions are also designed in part to encourage anyone seeking to acquire control of us to first negotiate with our board of directors. These provisions might also have the effect of preventing changes in our management. It is possible that these provisions could make it more difficult to accomplish transactions that stockholders might otherwise deem to be in their best interests. However, we believe that the advantages gained by protecting our ability to negotiate with any unsolicited and potentially unfriendly acquirer outweigh the disadvantages of discouraging such proposals, including those priced above the then-current market value of our common stock, because, among other reasons, the negotiation of such proposals could improve their terms.

Delaware Takeover Statute

We are subject to the provisions of Section 203 of the Delaware General Corporation Law. In general, Section 203 prohibits a publicly held Delaware corporation from engaging in a “business combination” with an “interested stockholder” for a three-year period following the time that this stockholder becomes an interested stockholder, unless the business combination is approved in a prescribed manner. Under Section 203, a business combination between a corporation and an interested stockholder is prohibited unless it satisfies one of the following conditions:

∎ before the stockholder became interested, our board of directors approved either the business combination or the transaction which resulted in the stockholder becoming an interested stockholder;

∎ upon consummation of the transaction which resulted in the stockholder becoming an interested stockholder, the interested stockholder owned at least 85% of the voting stock of the corporation outstanding at the time the transaction commenced, excluding for purposes of determining the voting stock outstanding, shares owned by persons who are directors and also officers, and employee stock plans, in some instances, but not the outstanding voting stock owned by the interested stockholder; or

∎ at or after the time the stockholder became interested, the business combination was approved by our board of directors and authorized at an annual or special meeting of the stockholders by the affirmative vote of at least two-thirds of the outstanding voting stock which is not owned by the interested stockholder.

Section 203 defines a business combination to include:

∎ any merger or consolidation involving the corporation and the interested stockholder;

∎ any sale, transfer, lease, pledge, exchange, mortgage or other disposition involving the interested stockholder of 10% or more of the assets of the corporation;

∎ subject to exceptions, any transaction that results in the issuance or transfer by the corporation of any stock of the corporation to the interested stockholder;

∎ subject to exceptions, any transaction involving the corporation that has the effect of increasing the proportionate share of the stock of any class or series of the corporation beneficially owned by the interested stockholder; or

∎ the receipt by the interested stockholder of the benefit of any loans, advances, guarantees, pledges or other financial benefits provided by or through the corporation.

In general, Section 203 defines an interested stockholder as any entity or person beneficially owning 15% or more of the outstanding voting stock of the corporation and any entity or person affiliated with or controlling or controlled by the entity or person.

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Provisions of our Certificate of Incorporation and By-laws

Our certificate of incorporation and by-laws include a number of provisions that may have the effect of delaying, deferring or discouraging another party from acquiring control of us and encouraging persons considering unsolicited tender offers or other unilateral takeover proposals to negotiate with our board of directors rather than pursue non-negotiated takeover attempts. These provisions include the items described below.

Board composition and filling vacancies. Our certificate of incorporation provides that directors may be removed only for cause by the affirmative vote of at least a majority of the shares present in person or by proxy at the meeting and entitled to vote at an election of directors. Furthermore, any vacancy on our board of directors, however occurring, including a vacancy resulting from an increase in the size of our board, may only be filled by the affirmative vote of a majority of our directors then in office even if less than a quorum.

No written consent of stockholders. Our certificate of incorporation provides that all stockholder actions are required to be taken by a vote of the stockholders at an annual or special meeting, and that stockholders may not take any action by written consent in lieu of a meeting.

Meetings of stockholders. Our certificate of incorporation provides that only the Chairperson of our board of directors, the Chief Executive Officer, the President or our board of directors acting pursuant to a majority of our board of directors may call special meetings of stockholders and only those matters set forth in the notice of the special meeting may be considered or acted upon at a special meeting of stockholders. Our by-laws limit the business that may be conducted at an annual meeting of stockholders to those matters properly brought before the meeting.

Advance notice requirements. Our by-laws establish advance notice procedures with regard to stockholder proposals relating to the nomination of candidates for election as directors or new business to be brought before meetings of our stockholders. These procedures provide that notice of stockholder proposals must be timely given in writing to our corporate secretary prior to the meeting at which the action is to be taken. Generally, to be timely, notice must be received at our principal executive offices not less than 45 days or more than 75 days before to the one-year anniversary of the date on which we first mailed our proxy materials or notice of availability of proxy materials (whichever is earlier) for the preceding year’s annual meeting. The notice must contain certain information specified in the by-laws.

Amendment to certificate of incorporation and by-laws. As required by the Delaware General Corporation Law, any amendment of our certificate of incorporation must first be approved by a majority of our board of directors and, if required by law or our certificate of incorporation, thereafter be approved by a majority of the outstanding shares entitled to vote on the amendment, and a majority of the outstanding shares of each class entitled to vote thereon as a class, except that the amendment of the provisions relating to stockholder action, directors, exclusive jurisdiction and the amendment of our certificate of incorporation must be approved by not less than sixty-six and two-thirds percent (66 2/3%) of the then outstanding voting securities, voting together as a single class.

Our by-laws may not be amended by stockholders. Our certificate of incorporation provides that our by-laws may be amended, altered, or repealed by our board of directors.

Undesignated preferred stock. Our certificate of incorporation provides for authorized shares of preferred stock. The existence of authorized but unissued shares of preferred stock may enable our board of directors to render more difficult or to discourage an attempt to obtain control of us by means of a merger, tender offer, proxy contest or otherwise. For example, if in the due exercise of its fiduciary obligations, our board of directors were to determine that a takeover proposal is not in the best interests of us or our stockholders, our board of directors could cause shares of preferred stock to be issued without stockholder approval in one or more private offerings or other transactions that might dilute the voting or other rights of the proposed acquirer or insurgent stockholder or stockholder group. In this regard, our certificate of incorporation grants our board of directors broad power to establish the rights and preferences of authorized and unissued shares of preferred stock. The issuance of shares of preferred stock could decrease the amount of earnings and assets available for distribution to holders of shares of common stock. The issuance may also adversely affect the rights and powers, including voting rights, of these holders and may have the effect of delaying, deterring or preventing a change in control of us.

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Exclusive jurisdiction for certain actions. Our certificate of incorporation provides that, unless we consent to the selection of an alternative forum, the Court of Chancery of the State of Delaware shall be the sole and exclusive forum for any derivative action or proceeding brought on our behalf, any action asserting a claim of breach of fiduciary duty, any action asserting a claim arising pursuant to the Delaware General Corporation Law (the “DGCL”), any action regarding our certificate of incorporation or our by-laws or any action asserting a claim against us that is governed by the internal affairs doctrine. Our certificate of incorporation further provides that the federal district courts of the United States of America will be the exclusive forum for resolving any complaint asserting a cause of action arising under the Securities Act. The choice of the Court of Chancery of the State of Delaware as the sole and exclusive forum for any derivative action or proceeding brought on our behalf does not apply to suits seeking to enforce a duty or liability created by the Securities Act or Exchange Act. The enforceability of similar choice of forum provisions in other companies’ certificates of incorporation and by-laws has been challenged in legal proceedings, and it is possible that a court could find these types of provisions to be inapplicable or unenforceable.

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DESCRIPTION OF DEBT SECURITIES

This section describes the general terms and provisions of our debt securities that we may issue from time to time. We may issue debt securities, in one or more series, as either senior or subordinated debt or as senior or subordinated convertible debt. While the terms we have summarized below will apply generally to any future debt securities we may offer under this prospectus, the applicable prospectus supplement or free writing prospectus will describe the specific terms of any debt securities offered through that prospectus supplement or free writing prospectus. The terms of any debt securities we offer under a prospectus supplement or free writing prospectus may differ from the terms we describe below. Unless the context requires otherwise, whenever we refer to the “indentures,” we also are referring to any supplemental indentures that specify the terms of a particular series of debt securities.

We will issue any senior debt securities under the senior indenture that we will enter into with the trustee named in the senior indenture. We will issue any subordinated debt securities under the subordinated indenture that we will enter into with the trustee named in the subordinated indenture. We have filed forms of these documents as exhibits to the registration statement, of which this prospectus is a part, and supplemental indentures and forms of debt securities containing the terms of the debt securities being offered will be filed as exhibits to the registration statement of which this prospectus is a part or will be incorporated by reference from reports that we file with the SEC.

The indentures will be qualified under the Trust Indenture Act of 1939, as amended (the “Trust Indenture Act”). We use the term “trustee” to refer to either the trustee under the senior indenture or the trustee under the subordinated indenture, as applicable.

The following summaries of material provisions of the senior debt securities, the subordinated debt securities and the indentures are subject to, and qualified in their entirety by reference to, all of the provisions of the indenture applicable to a particular series of debt securities. We urge you to read the applicable prospectus supplement or free writing prospectus and any related free writing prospectuses related to the debt securities that we may offer under this prospectus, as well as the complete applicable indenture that contains the terms of the debt securities. Except as we may otherwise indicate, the terms of the senior indenture and the subordinated indenture are identical.

General

We will describe in the applicable prospectus supplement or free writing prospectus the terms of the series of debt securities being offered, including:

∎ the title;

∎ the principal amount being offered, and if a series, the total amount authorized and the total amount outstanding;

∎ any limit on the amount that may be issued;

∎ whether or not we will issue the series of debt securities in global form, and, if so, the terms and who the depository will be;

∎ the maturity date;

∎ whether and under what circumstances, if any, we will pay additional amounts on any debt securities held by a person who is not a United States person for tax purposes, and whether we can redeem;

∎ the debt securities if we have to pay such additional amounts;

∎ the annual interest rate, which may be fixed or variable, or the method for determining the rate and the date interest will begin to accrue, the dates interest will be payable and the regular record dates for interest payment dates or the method for determining such dates;

∎ whether or not the debt securities will be secured or unsecured, and the terms of any secured debt;

∎ the terms of the subordination of any series of subordinated debt;

∎ the place where payments will be payable;

∎ restrictions on transfer, sale or other assignment, if any;

∎ our right, if any, to defer payment of interest and the maximum length of any such deferral period;

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∎ the date, if any, after which, the conditions upon which, and the price at which, we may, at our option, redeem the series of debt securities pursuant to any optional or provisional redemption provisions and the terms of those redemption provisions;

∎ the date, if any, on which, and the price at which we are obligated, pursuant to any mandatory sinking fund or analogous fund provisions or otherwise, to redeem, or at the holder’s option, to purchase, the series of debt securities and the currency or currency unit in which the debt securities are payable;

∎ whether the indenture will restrict our ability or the ability of our subsidiaries to:

∎ incur additional indebtedness;

∎ issue additional securities;

∎ create liens;

∎ pay dividends or make distributions in respect of our capital stock or the capital stock of our subsidiaries;

∎ redeem capital stock;

∎ place restrictions on our subsidiaries’ ability to pay dividends, make distributions or transfer assets;

∎ make investments or other restricted payments;

∎ sell or otherwise dispose of assets;

∎ enter into sale-leaseback transactions;

∎ engage in transactions with stockholders or affiliates;

∎ issue or sell stock of our subsidiaries; or

∎ effect a consolidation or merger;

∎ whether the indenture will require us to maintain any interest coverage, fixed charge, cash flow-based, asset-based or other financial ratios;

∎ a discussion of certain material or special United States federal income tax considerations applicable to the debt securities;

∎ information describing any book-entry features;

∎ provisions for a sinking fund purchase or other analogous fund, if any;

∎ the applicability of the provisions in the indenture on discharge;

∎ whether the debt securities are to be offered at a price such that they will be deemed to be offered at an “original issue discount” as defined in paragraph (a) of Section 1273 of the Internal Revenue Code of 1986, as amended;

∎ the denominations in which we will issue the series of debt securities, if other than denominations of $1,000 and any integral multiple thereof;

∎ the currency of payment of debt securities if other than U.S. dollars and the manner of determining the equivalent amount in U.S. dollars; and

∎ any other specific terms, preferences, rights or limitations of, or restrictions on, the debt securities, including any additional events of default or covenants provided with respect to the debt securities, and any terms that may be required by us or advisable under applicable laws or regulations or advisable in connection with the marketing of the debt securities.

Conversion or Exchange Rights

We will set forth in the applicable prospectus supplement or free writing prospectus the terms on which a series of debt securities may be convertible into or exchangeable for our common stock, our preferred stock or other securities (including securities of a third-party). We will include provisions as to whether conversion or exchange is mandatory, at the option of the holder or at our option. We may include provisions pursuant to which the number of shares of our common stock, our preferred stock or other securities (including securities of a third-party) that the holders of the series of debt securities receive would be subject to adjustment.

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Consolidation, Merger or Sale

Unless we provide otherwise in the prospectus supplement or free writing prospectus applicable to a particular series of debt securities, the indentures will not contain any covenant that restricts our ability to merge or consolidate, or sell, convey, transfer or otherwise dispose of all or substantially all of our assets. However, any successor to or acquirer of such assets must assume all of our obligations under the indentures or the debt securities, as appropriate. If the debt securities are convertible into or exchangeable for other securities of ours or securities of other entities, the person with whom we consolidate or merge or to whom we sell all of our property must make provisions for the conversion of the debt securities into securities that the holders of the debt securities would have received if they had converted the debt securities before the consolidation, merger or sale.

Events of Default Under the Indenture

Unless we provide otherwise in the prospectus supplement or free writing prospectus applicable to a particular series of debt securities, the following are events of default under the indentures with respect to any series of debt securities that we may issue:

∎ if we fail to pay interest when due and payable and our failure continues for 90 days and the time for payment has not been extended;

∎ if we fail to pay the principal, premium or sinking fund payment, if any, when due and payable at maturity, upon redemption or repurchase or otherwise, and the time for payment has not been extended;

∎ if we fail to observe or perform any other covenant contained in the debt securities or the indentures, other than a covenant specifically relating to another series of debt securities, and our failure continues for 90 days after we receive notice from the trustee or holders of at least 25% in aggregate principal amount of the outstanding debt securities of the applicable series; and

∎ if specified events of bankruptcy, insolvency or reorganization occur.

We will describe in each applicable prospectus supplement or free writing prospectus any additional events of default relating to the relevant series of debt securities.

If an event of default with respect to debt securities of any series occurs and is continuing, other than an event of default specified in the last bullet point above, the trustee or the holders of at least 25% in aggregate principal amount of the outstanding debt securities of that series, by notice to us in writing, and to the trustee if notice is given by such holders, may declare the unpaid principal, premium, if any, and accrued interest, if any, due and payable immediately. If an event of default specified in the last bullet point above occurs with respect to us, the unpaid principal, premium, if any, and accrued interest, if any, of each issue of debt securities then outstanding shall be due and payable without any notice or other action on the part of the trustee or any holder.

The holders of a majority in principal amount of the outstanding debt securities of an affected series may waive any default or event of default with respect to the series and its consequences, except defaults or events of default regarding payment of principal, premium, if any, or interest, unless we have cured the default or event of default in accordance with the indenture. Any waiver shall cure the default or event of default.

Subject to the terms of the indentures, if an event of default under an indenture shall occur and be continuing, the trustee will be under no obligation to exercise any of its rights or powers under such indenture at the request or direction of any of the holders of the applicable series of debt securities, unless such holders have offered the trustee reasonable indemnity or security satisfactory to it against any loss, liability or expense. The holders of a majority in principal amount of the outstanding debt securities of any series will have the right to direct the time, method and place of conducting any proceeding for any remedy available to the trustee, or exercising any trust or power conferred on the trustee, with respect to the debt securities of that series, provided that:

∎ the direction so given by the holder is not in conflict with any law or the applicable indenture; and

∎ subject to its duties under the Trust Indenture Act, the trustee need not take any action that might involve it in personal liability or might be unduly prejudicial to the holders not involved in the proceeding.

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A holder of the debt securities of any series will have the right to institute a proceeding under the indentures or to appoint a receiver or trustee, or to seek other remedies if:

∎ the holder has given written notice to the trustee of a continuing event of default with respect to that series;

∎ the holders of at least 25% in aggregate principal amount of the outstanding debt securities of that series have made written request, and such holders have offered reasonable indemnity to the trustee or security satisfactory to it against any loss, liability or expense or to be incurred in compliance with instituting the proceeding as trustee; and

∎ the trustee does not institute the proceeding, and does not receive from the holders of a majority in aggregate principal amount of the outstanding debt securities of that series other conflicting directions within 90 days after the notice, request and offer.

These limitations do not apply to a suit instituted by a holder of debt securities if we default in the payment of the principal, premium, if any, or interest on, the debt securities, or other defaults that may be specified in the applicable prospectus supplement or free writing prospectus.

We will periodically file statements with the trustee regarding our compliance with specified covenants in the indentures.

Modification of Indenture; Waiver

Subject to the terms of the indenture for any series of debt securities that we may issue, we and the trustee may change an indenture without the consent of any holders with respect to the following specific matters:

∎ to fix any ambiguity, defect or inconsistency in the indenture;

∎ to comply with the provisions described above under “Description of Our Debt Securities — Consolidation, Merger or Sale;”

∎ to comply with any requirements of the SEC in connection with the qualification of any indenture under the Trust Indenture Act;

∎ to add to, delete from or revise the conditions, limitations, and restrictions on the authorized amount, terms, or purposes of issue, authentication and delivery of debt securities, as set forth in the indenture;

∎ to provide for the issuance of and establish the form and terms and conditions of the debt securities of any series as provided under “Description of Our Debt Securities - General,” to establish the form of any certifications required to be furnished pursuant to the terms of the indenture or any series of debt securities, or to add to the rights of the holders of any series of debt securities;

∎ to evidence and provide for the acceptance of appointment hereunder by a successor trustee;

∎ to provide for uncertificated debt securities and to make all appropriate changes for such purpose;

∎ to add to our covenants such new covenants, restrictions, conditions or provisions for the benefit of the holders, to make the occurrence, or the occurrence and the continuance, of a default in any such additional covenants, restrictions, conditions or provisions an event of default or to surrender any right or power conferred to us in the indenture; or

∎ to change anything that does not materially adversely affect the interests of any holder of debt securities of any series.

In addition, under the indentures, the rights of holders of a series of debt securities may be changed by us and the trustee with the written consent of the holders of at least a majority in aggregate principal amount of the outstanding debt securities of each series that is affected. However, subject to the terms of the indenture for any series of debt securities that we may issue or as otherwise provided in the prospectus supplement or free writing prospectus applicable to a particular series of debt securities, we and the trustee may make the following changes only with the consent of each holder of any outstanding debt securities affected:

∎ extending the stated maturity of the series of debt securities;

∎ reducing the principal amount, reducing the rate of or extending the time of payment of interest, or reducing any premium payable upon the redemption or repurchase of any debt securities; or

∎ reducing the percentage of debt securities, the holders of which are required to consent to any amendment, supplement, modification or waiver.

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Discharge

Each indenture provides that, subject to the terms of the indenture and any limitation otherwise provided in the prospectus supplement or free writing prospectus applicable to a particular series of debt securities, we can elect to be discharged from our obligations with respect to one or more series of debt securities, except for specified obligations, including obligations to:

∎ register the transfer or exchange of debt securities of the series;

∎ replace stolen, lost or mutilated debt securities of the series;

∎ maintain paying agencies;

∎ hold monies for payment in trust;

∎ recover excess money held by the trustee;

∎ compensate and indemnify the trustee; and

∎ appoint any successor trustee.

In order to exercise our rights to be discharged, we must deposit with the trustee money or government obligations sufficient to pay all the principal of, any premium and interest on, the debt securities of the series on the dates payments are due.

Form, Exchange and Transfer

We will issue the debt securities of each series only in fully registered form without coupons and, unless we otherwise specify in the applicable prospectus supplement or free writing prospectus, in denominations of $1,000 and any integral multiple thereof. The indentures provide that we may issue debt securities of a series in temporary or permanent global form and as book-entry securities that will be deposited with, or on behalf of, The Depository Trust Company or another depository named by us and identified in a prospectus supplement or free writing prospectus with respect to that series.

At the option of the holder, subject to the terms of the indentures and the limitations applicable to global securities described in the applicable prospectus supplement or free writing prospectus, the holder of the debt securities of any series can exchange the debt securities for other debt securities of the same series, in any authorized denomination and of like tenor and aggregate principal amount.

Subject to the terms of the indentures and the limitations applicable to global securities set forth in the applicable prospectus supplement or free writing prospectus, holders of the debt securities may present the debt securities for exchange or for registration of transfer, duly endorsed or with the form of transfer endorsed thereon duly executed if so required by us or the security registrar, at the office of the security registrar or at the office of any transfer agent designated by us for this purpose. Unless otherwise provided in the debt securities that the holder presents for transfer or exchange, we will make no service charge for any registration of transfer or exchange, but we may require payment of any taxes or other governmental charges.

We will name in the applicable prospectus supplement or free writing prospectus the security registrar, and any transfer agent in addition to the security registrar, that we initially designate for any debt securities.

We may at any time designate additional transfer agents or rescind the designation of any transfer agent or approve a change in the office through which any transfer agent acts, except that we will be required to maintain a transfer agent in each place of payment for the debt securities of each series. If we elect to redeem the debt securities of any series, we will not be required to:

∎ issue, register the transfer of, or exchange any debt securities of that series during a period beginning at the opening of business 15 days before the day of mailing of a notice of redemption of any debt securities that may be selected for redemption and ending at the close of business on the day of the mailing; or

∎ register the transfer of or exchange any debt securities so selected for redemption, in whole or in part, except the unredeemed portion of any debt securities we are redeeming in part.

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Information Concerning the Trustee

The trustee, other than during the occurrence and continuance of an event of default under an indenture, undertakes to perform only those duties as are specifically set forth in the applicable indenture. Upon an event of default under an indenture, the trustee must use the same degree of care as a prudent person would exercise or use in the conduct of his or her own affairs.

Subject to this provision, the trustee is under no obligation to exercise any of the powers given it by the indentures at the request of any holder of debt securities unless it is offered reasonable security and indemnity against the costs, expenses and liabilities that it might incur.

Payment and Paying Agents

Unless we otherwise indicate in the applicable prospectus supplement or free writing prospectus, we will make payment of the interest on any debt securities on any interest payment date to the person in whose name the debt securities, or one or more predecessor securities, are registered at the close of business on the regular record date for the interest.

We will pay principal of and any premium and interest on the debt securities of a particular series at the office of the paying agents designated by us, except that unless we otherwise indicate in the applicable prospectus supplement or free writing prospectus, we will make interest payments by check that we will mail to the holder or by wire transfer to certain holders. Unless we otherwise indicate in the applicable prospectus supplement or free writing prospectus, we will designate the corporate trust office of the trustee as our sole paying agent for payments with respect to debt securities of each series. We will name in the applicable prospectus supplement or free writing prospectus any other paying agents that we initially designate for the debt securities of a particular series. We will maintain a paying agent in each place of payment for the debt securities of a particular series.

All money we pay to a paying agent or the trustee for the payment of the principal of or any premium or interest on any debt securities that remains unclaimed at the end of two years after such principal, premium or interest has become due and payable will be repaid to us, and the holder of the debt security thereafter may look only to us for payment thereof.

Governing Law

The indentures and the debt securities will be governed by and construed in accordance with the laws of the State of New York, except to the extent that the Trust Indenture Act is applicable.

Ranking of Debt Securities

The subordinated debt securities will be subordinate and junior in priority of payment to certain of our other indebtedness to the extent described in a prospectus supplement or free writing prospectus. The subordinated indenture does not limit the amount of subordinated debt securities that we may issue. It also does not limit us from issuing any other secured or unsecured debt.

The senior debt securities will rank equally in right of payment to all our other senior unsecured debt. The senior indenture does not limit the amount of senior debt securities that we may issue. It also does not limit us from issuing any other secured or unsecured debt.

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DESCRIPTION OF WARRANTS

The following description, together with the additional information we may include in any applicable prospectus supplements, summarizes the material terms and provisions of the warrants that we may offer under this prospectus and the related warrant agreements and warrant certificates. While the terms summarized below will apply generally to any warrants that we may offer, we will describe the particular terms of any series of warrants in more detail in the applicable prospectus supplement. If we indicate in the prospectus supplement, the terms of any warrants offered under that prospectus supplement may differ from the terms described below. Specific warrant agreements will contain additional important terms and provisions and will be incorporated by reference as an exhibit to the registration statement, which includes this prospectus.

General

We may issue warrants for the purchase of common stock, preferred stock and/or debt securities in one or more series. We may issue warrants independently or together with common stock, preferred stock and/or debt securities, and the warrants may be attached to or separate from these securities.

We will evidence each series of warrants by warrant certificates that we will issue under a separate warrant agreement. We will enter into the warrant agreement with a warrant agent. We will indicate the name and address of the warrant agent in the applicable prospectus supplement relating to a particular series of warrants.

We will describe in the applicable prospectus supplement the terms of the series of warrants, including:

∎ the offering price and aggregate number of warrants offered;

∎ the currency for which the warrants may be purchased;

∎ if applicable, the designation and terms of the securities with which the warrants are issued and the number of warrants issued with each such security or each principal amount of such security;

∎ if applicable, the date on and after which the warrants and the related securities will be separately transferable;

∎ in the case of warrants to purchase debt securities, the principal amount of debt securities purchasable upon exercise of one warrant and the price at, and currency in which, this principal amount of debt securities may be purchased upon such exercise;

∎ in the case of warrants to purchase common stock or preferred stock, the number of shares of common stock or preferred stock, as the case may be, purchasable upon the exercise of one warrant and the price at which these shares may be purchased upon such exercise;

∎ the effect of any merger, consolidation, sale or other disposition of our business on the warrant agreement and the warrants;

∎ the terms of any rights to redeem or call the warrants;

∎ any provisions for changes to or adjustments in the exercise price or number of securities issuable upon exercise of the warrants;

∎ the periods during which, and places at which, the warrants are exercisable;

∎ the manner of exercise;

∎ the dates on which the right to exercise the warrants will commence and expire;

∎ the manner in which the warrant agreement and warrants may be modified;

∎ federal income tax consequences of holding or exercising the warrants;

∎ the terms of the securities issuable upon exercise of the warrants; and

∎ any other specific terms, preferences, rights or limitations of or restrictions on the warrants.

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DESCRIPTION OF UNITS

We may issue units comprised of shares of common stock, shares of preferred stock, debt securities and warrants in any combination. We may issue units in such amounts and in as many distinct series as we wish. This section outlines certain provisions of the units that we may issue. If we issue units, they will be issued under one or more unit agreements to be entered into between us and a bank or other financial institution, as unit agent. The information described in this section may not be complete in all respects and is qualified entirely by reference to the unit agreement with respect to the units of any particular series. The specific terms of any series of units offered will be described in the applicable prospectus supplement. If so described in a particular supplement, the specific terms of any series of units may differ from the general description of terms presented below. We urge you to read any prospectus supplement related to any series of units we may offer, as well as the complete unit agreement and unit certificate that contain the terms of the units. If we issue units, forms of unit agreements and unit certificates relating to such units will be incorporated by reference as exhibits to the registration statement, which includes this prospectus.

Each unit that we may issue will be issued so that the holder of the unit is also the holder of each security included in the unit. Thus, the holder of a unit will have the rights and obligations of a holder of each included security. The unit agreement under which a unit is issued may provide that the securities included in the unit may not be held or transferred separately, at any time or at any time before a specified date. The applicable prospectus supplement may describe:

∎ the designation and terms of the units and of the securities comprising the units, including whether and under what circumstances those securities may be held or transferred separately;

∎ any provisions of the governing unit agreement;

∎ the price or prices at which such units will be issued;

∎ the applicable United States federal income tax considerations relating to the units;

∎ any provisions for the issuance, payment, settlement, transfer or exchange of the units or of the securities comprising the units; and

∎ any other terms of the units and of the securities comprising the units.

The provisions described in this section, as well as those described under “Description of Capital Stock,” “Description of Debt Securities” and “Description of Warrants” will apply to the securities included in each unit, to the extent relevant and as may be updated in any prospectus supplements.

Issuance in Series

We may issue units in such amounts and in as many distinct series as we wish. This section summarizes terms of the units that apply generally to all series. Most of the financial and other specific terms of a particular series of units will be described in the applicable prospectus supplement.

Unit Agreements

We will issue the units under one or more unit agreements to be entered into between us and a bank or other financial institution, as unit agent. We may add, replace or terminate unit agents from time to time. We will identify the unit agreement under which each series of units will be issued and the unit agent under that agreement in the applicable prospectus supplement.

The following provisions will generally apply to all unit agreements unless otherwise stated in the applicable prospectus supplement:

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Modification without Consent

We and the applicable unit agent may amend any unit or unit agreement without the consent of any holder:

to cure any ambiguity, including modifying any provisions of the governing unit agreement that differ from those described below;

∎ to correct or supplement any defective or inconsistent provision; or

∎ to make any other change that we believe is necessary or desirable and will not adversely affect the interests of the affected holders in any material respect.

We do not need any approval to make changes that affect only units to be issued after the changes take effect. We may also make changes that do not adversely affect a particular unit in any material respect, even if they adversely affect other units in a material respect. In those cases, we do not need to obtain the approval of the holder of the unaffected unit; we need only obtain any required approvals from the holders of the affected units.

Modification with Consent

We may not amend any particular unit or a unit agreement with respect to any particular unit unless we obtain the consent of the holder of that unit, if the amendment would:

∎ impair any right of the holder to exercise or enforce any right under a security included in the unit if the terms of that security require the consent of the holder to any changes that would impair the exercise or enforcement of that right; or

∎ reduce the percentage of outstanding units or any series or class the consent of whose holders is required to amend that series or class, or the applicable unit agreement with respect to that series or class, as described below.

∎ Any other change to a particular unit agreement and the units issued under that agreement would require the following approval:

∎ If the change affects only the units of a particular series issued under that agreement, the change must be approved by the holders of a majority of the outstanding units of that series; or

∎ If the change affects the units of more than one series issued under that agreement, it must be approved by the holders of a majority of all outstanding units of all series affected by the change, with the units of all the affected series voting together as one class for this purpose.

These provisions regarding changes with majority approval also apply to changes affecting any securities issued under a unit agreement, as the governing document.

In each case, the required approval must be given by written consent.

Unit Agreements Will Not Be Qualified under Trust Indenture Act

No unit agreement will be qualified as an indenture, and no unit agent will be required to qualify as a trustee, under the Trust Indenture Act. Therefore, holders of units issued under unit agreements will not have the protections of the Trust Indenture Act with respect to their units.

Mergers and Similar Transactions Permitted; No Restrictive Covenants or Events of Default

The unit agreements will not restrict our ability to merge or consolidate with, or sell our assets to, another corporation or other entity or to engage in any other transactions. If at any time we merge or consolidate with, or sell our assets substantially as an entirety to, another corporation or other entity, the successor entity will succeed to and assume our obligations under the unit agreements. We will then be relieved of any further obligation under these agreements.

The unit agreements will not include any restrictions on our ability to put liens on our assets, nor will they restrict our ability to sell our assets. The unit agreements also will not provide for any events of default or remedies upon the occurrence of any events of default.

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Governing Law

The unit agreements and the units will be governed by Delaware law.

Form, Exchange and Transfer

We will issue each unit in global—i.e., book-entry—form only. Units in book-entry form will be represented by a global security registered in the name of a depositary, which will be the holder of all the units represented by the global security. Those who own beneficial interests in a unit will do so through participants in the depositary’s system, and the rights of these indirect owners will be governed solely by the applicable procedures of the depositary and its participants. We will describe book-entry securities, and other terms regarding the issuance and registration of the units in the applicable prospectus supplement.

Each unit and all securities comprising the unit will be issued in the same form.

If we issue any units in registered, non-global form, the following will apply to them.

The units will be issued in the denominations stated in the applicable prospectus supplement. Holders may exchange their units for units of smaller denominations or combined into fewer units of larger denominations, as long as the total amount is not changed.

∎ Holders may exchange or transfer their units at the office of the unit agent. Holders may also replace lost, stolen, destroyed or mutilated units at that office. We may appoint another entity to perform these functions or perform them ourselves.

∎ Holders will not be required to pay a service charge to transfer or exchange their units, but they may be required to pay for any tax or other governmental charge associated with the transfer or exchange. The transfer or exchange, and any replacement, will be made only if our transfer agent is satisfied with the holder’s proof of legal ownership. The transfer agent may also require an indemnity before replacing any units.

∎ If we have the right to redeem, accelerate or settle any units before their maturity, and we exercise our right as to less than all those units or other securities, we may block the exchange or transfer of those units during the period beginning 15 days before the day we mail the notice of exercise and ending on the day of that mailing, in order to freeze the list of holders to prepare the mailing. We may also refuse to register transfers of or exchange any unit selected for early settlement, except that we will continue to permit transfers and exchanges of the unsettled portion of any unit being partially settled. We may also block the transfer or exchange of any unit in this manner if the unit includes securities that are or may be selected for early settlement.

Only the depositary will be entitled to transfer or exchange a unit in global form, since it will be the sole holder of the unit.

Payments and Notices

In making payments and giving notices with respect to our units, we will follow the procedures as described in the applicable prospectus supplement.

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PLAN OF DISTRIBUTION

We may sell the securities offered through this prospectus and any accompanying prospectus supplement, if required, in any of the following ways: (i) to or through underwriters or dealers, (ii) directly to purchasers, including our affiliates, (iii) through agents, (iv) in an “at the market offering,” within the meaning of Rule 415(a)(4) of the Securities Act, or (v) through a combination of any of these methods or any other method permitted by law. The securities may be distributed at a fixed price or prices, which may be changed, market prices prevailing at the time of sale, prices related to the prevailing market prices, or negotiated prices, either:

∎ on or through the facilities of The Nasdaq Capital Market or any other securities exchange or quotation or trading service on which such securities may be listed, quoted or traded at the time of sale; and/or

∎ to or through a market maker otherwise than on The Nasdaq Capital Market or such other securities exchanges or quotation or trading services.

∎ In addition, we may issue the securities as a dividend or distribution or in a subscription rights offering to our existing security holders.

We may directly solicit offers to purchase securities, or agents may be designated to solicit such offers. In the prospectus supplement relating to such offering, we will name any agent that could be viewed as an underwriter under the Securities Act and describe any commissions that we must pay to any such agent. Any such agent will be acting on a best efforts basis for the period of its appointment or, if indicated in the applicable prospectus supplement, on a firm commitment basis. This prospectus may be used in connection with any offering of our securities through any of these methods or other methods described in the applicable prospectus supplement.

The distribution of the securities may be effected from time to time in one or more transactions:

∎ at a fixed price, or prices, which may be changed from time to time;

∎ at market prices prevailing at the time of sale;

∎ at prices related to such prevailing market prices; or

∎ at negotiated prices.

Each prospectus supplement will describe the method of distribution of the securities and any applicable restrictions.

The prospectus supplement with respect to the securities of a particular series will describe the terms of the offering of the securities, including the following:

∎ the name of the agent or any underwriters;

∎ the public offering or purchase price;

∎ any discounts and commissions to be allowed or paid to the agent or underwriters;

∎ all other items constituting underwriting compensation;

∎ any discounts and commissions to be allowed or paid to dealers; and

∎ any exchanges on which the securities will be listed.

If any underwriters or agents are used in the sale of the securities in respect of which this prospectus is delivered, we will enter into an underwriting agreement, sales agreement or other agreement with them at the time of sale to them, and we will set forth in the prospectus supplement relating to such offering the names of the underwriters or agents and the terms of the related agreement with them.

In connection with the offering of securities, we may grant to the underwriters an option to purchase additional securities with an additional underwriting commission, as may be set forth in the accompanying prospectus supplement. If we grant any such option, the terms of such option will be set forth in the prospectus supplement for such securities.

If a dealer is used in the sale of the securities in respect of which the prospectus is delivered, we will sell such securities to the dealer, as principal. The dealer, who may be deemed to be an “underwriter” as that term is defined in the Securities Act, may then resell such securities to the public at varying prices to be determined by such dealer at the time of resale.

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If we offer securities in a subscription rights offering to our existing security holders, we may enter into a standby underwriting agreement with dealers, acting as standby underwriters. We may pay the standby underwriters a commitment fee for the securities they commit to purchase on a standby basis. If we do not enter into a standby underwriting arrangement, we may retain a dealer-manager to manage a subscription rights offering for us.

Agents, underwriters, dealers and other persons may be entitled under agreements which they may enter into with us to indemnification by us against certain civil liabilities, including liabilities under the Securities Act, and may be customers of, engage in transactions with or perform services for us in the ordinary course of business.

If so indicated in the applicable prospectus supplement, we will authorize underwriters or other persons acting as our agents to solicit offers by certain institutions to purchase securities from us pursuant to delayed delivery contracts providing for payment and delivery on the date stated in the prospectus supplement. Each contract will be for an amount not less than, and the aggregate amount of securities sold pursuant to such contracts shall not be less nor more than, the respective amounts stated in the prospectus supplement. Institutions with whom the contracts, when authorized, may be made include commercial and savings banks, insurance companies, pension funds, investment companies, educational and charitable institutions and other institutions, but shall in all cases be subject to our approval. Delayed delivery contracts will not be subject to any conditions except that:

∎ the purchase by an institution of the securities covered under that contract shall not at the time of delivery be prohibited under the laws of the jurisdiction to which that institution is subject; and

∎ if the securities are also being sold to underwriters acting as principals for their own account, the underwriters shall have purchased such securities not sold for delayed delivery. The underwriters and other persons acting as our agents will not have any responsibility in respect of the validity or performance of delayed delivery contracts.

Offered securities may also be offered and sold, if so indicated in the prospectus supplement, in connection with a remarketing upon their purchase, in accordance with a redemption or repayment pursuant to their terms, or otherwise, by one or more remarketing firms, acting as principals for their own accounts or as agents for us. Any remarketing firm will be identified and the terms of its agreement, if any, with us and its compensation will be described in the applicable prospectus supplement. Remarketing firms may be deemed to be underwriters in connection with their remarketing of offered securities.

Certain agents, underwriters and dealers, and their associates and affiliates, may be customers of, have borrowing relationships with, engage in other transactions with, or perform services, including investment banking services, for us or one or more of our respective affiliates in the ordinary course of business.

Certain underwriters may use this prospectus and any accompanying prospectus supplement for offers and sales related to market-making transactions in the securities. These underwriters may act as principal or agent in these transactions, and the sales will be made at prices related to prevailing market prices at the time of sale. Any underwriters involved in the sale of the securities may qualify as “underwriters” within the meaning of Section 2(a)(11) of the Securities Act. In addition, the underwriters’ commissions, discounts or concessions may qualify as underwriters’ compensation under the Securities Act and the rules of the Financial Industry Regulatory Authority (“FINRA”).

In order to facilitate the offering of the securities, any underwriters may engage in transactions that stabilize, maintain or otherwise affect the price of the securities or any other securities the prices of which may be used to determine payments on such securities. Specifically, any underwriters may over allot in connection with the offering, creating a short position for their own accounts. In addition, to cover overallotments or to stabilize the price of the securities or of any such other securities, the underwriters may bid for, and purchase, the securities or any such other securities in the open market. Finally, in any offering of the securities through a syndicate of underwriters, the underwriting syndicate may reclaim selling concessions allowed to an underwriter or a dealer for distributing the securities in the offering if the syndicate repurchases previously distributed securities in transactions to cover syndicate short positions, in stabilization transactions or otherwise. Any of these activities may stabilize or maintain the market price of the securities above independent market levels. Any such underwriters are not required to engage in these activities and may end any of these activities at any time.

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We may engage in at the market offerings into an existing trading market in accordance with Rule 415(a)(4) under the Securities Act. In addition, we may enter into derivative transactions with third parties, or sell securities not covered by this prospectus to third parties in negotiated transactions.

If the applicable prospectus supplement so indicates, in connection with those derivatives, the third parties may sell securities covered by this prospectus and the applicable prospectus supplement, including in short sale transactions. If so, the third party may use securities pledged by us or borrowed from us or others to settle those sales or to close out any related open borrowings of stock, and may use securities received from us in settlement of those derivatives to close out any related open borrowings of stock. The third party in such sale transactions will be an underwriter and, if not identified in this prospectus, will be named in the applicable prospectus supplement (or a post-effective amendment). In addition, we may otherwise loan or pledge securities to a financial institution or other third party that in turn may sell the securities short using this prospectus and an applicable prospectus supplement. Such financial institution or other third party may transfer its economic short position to investors in our securities or in connection with a concurrent offering of other securities.

Under Rule 15c6-1 of the Exchange Act, trades in the secondary market generally are required to settle in one business day, unless the parties to any such trade expressly agree otherwise. The applicable prospectus supplement may provide that the original issue date for your securities may be more than two scheduled business days after the trade date for your securities. Accordingly, in such a case, if you wish to trade securities on any date prior to the second business day before the original issue date for your securities, you will be required, by virtue of the fact that your securities initially are expected to settle in more than two scheduled business days after the trade date for your securities, to make alternative settlement arrangements to prevent a failed settlement.

The securities may be new issues of securities and may have no established trading market. The securities may or may not be listed on a national securities exchange. We can make no assurance as to the liquidity of or the existence of trading markets for any of the securities.

The specific terms of any lock-up provisions in respect of any given offering will be described in the applicable prospectus supplement.

Any underwriters, dealers and agents may engage in transactions with us, or perform services for us, in the ordinary course of business for which they receive compensation.

The anticipated date of delivery of offered securities will be set forth in the applicable prospectus supplement relating to each offer.

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LEGAL MATTERS

Certain legal matters in connection with this offering will be passed upon for us by Goodwin Procter LLP, Boston, Massachusetts. Any underwriters will also be advised about the validity of the securities and other legal matters by their own counsel, which will be named in the prospectus supplement.

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EXPERTS

The consolidated financial statements of Inhibikase Therapeutics, Inc. and Subsidiary for the two years ended December 31, 2024, have been audited by CohnReznick LLP, independent registered public accounting firm, as set forth in their report thereon appearing in Inhibikase Therapeutics, Inc. and Subsidiary Annual Report on Form 10-K for the year ended December 31, 2024, and incorporated by reference herein. Such consolidated financial statements are incorporated by reference herein in reliance upon such report, given on the authority of such firm as experts in accounting and auditing.

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WHERE YOU CAN FIND MORE INFORMATION

We have filed with the SEC a registration statement on Form S-3 under the Securities Act with respect to the securities offered by this prospectus. This prospectus does not contain all of the information set forth in the registration statement and its exhibits and schedules in accordance with SEC rules and regulations. For further information with respect to us and the securities being offered by this prospectus, you should read the registration statement of which this prospectus is a part, including its exhibits and schedules. Statements contained in this prospectus, including documents that we have incorporated by reference, as to the contents of any contract or other document referred to are not necessarily complete, and, with respect to any contract or other document filed as an exhibit to the registration statement or any other such document, each such statement is qualified in all respects by reference to the corresponding exhibit. You should review the complete contract or other document to evaluate these statements. You may obtain copies of the registration statement and its exhibits via the SEC’s EDGAR database or our website.

We file annual, quarterly and current reports, proxy statements and other documents with the SEC under the U.S. Exchange Act. The SEC maintains a website that contains reports, proxy and information statements and other information regarding issuers, including us, that file electronically with the SEC. You may obtain documents that we file with the SEC at www.sec.gov.

We also make these documents available on our website at http:www.inhibikase.com. Our website and the information contained in, or that can be accessed through, our website is not incorporated by reference in this prospectus or any accompanying prospectus supplement, and you should not consider it part of this prospectus or any accompanying prospectus supplement. We have included our website address in this prospectus solely as an inactive textual reference.

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INCORPORATION BY REFERENCE

The SEC allows us to incorporate by reference in this prospectus the information and reports we file with it, which means that we can disclose important information to you by referring you to these documents. The information that we incorporate by reference in this prospectus is considered to be part of this prospectus. Because we are incorporating by reference future filings with the SEC, this prospectus is continually updated and those future filings may modify or supersede some of the information included or incorporated in this prospectus. This means that you must look at all of the SEC filings that we incorporate by reference to determine if any of the statements in this prospectus or in any document previously incorporated by reference have been modified or superseded. This prospectus incorporates by reference the documents listed below and any future filings we make with the SEC under Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act, including all filings made after the date of the filing of this registration statement and prior to the effectiveness of this registration statement, except as to any portion of any future report or document that is not deemed filed under such provisions until we sell all of the securities:

∎ Annual Report on Form 10-K for the year ended December 31, 2024, filed with the SEC on March 27, 2025, as amended by a Form 10-K/A, filed with the SEC on April 25, 2025;

∎ Quarterly Report on Form 10-Q for the quarter ended March 31, 2025, filed with the SEC on May 14, 2025;

∎ Current Reports on Form 8-K filed with the SEC on January 6, 2025, January  29, 2025, February 18, 2025, February 24, 2025 and April 14, 2025; and

∎ The description of our common stock contained in our Registration Statement on Form 8-A (File No. 001-39676), filed with the SEC under Section 12(b) of the Exchange Act, filed with the SEC on October 29, 2020, including any amendments or reports filed for the purpose of updating such description.

In addition, all reports and other documents filed by us pursuant to the Exchange Act after the date of the initial registration statement and prior to effectiveness of the registration statement shall be deemed to be incorporated by reference into this prospectus.

Notwithstanding the foregoing, unless specifically stated to the contrary, information that we furnish (and that is not deemed “filed” with the SEC) under Items 2.02 and 7.01 of any Current Report on Form 8-K, including the related exhibits under Item 9.01, is not incorporated by reference into this prospectus or the registration statement of which this prospectus is a part.

Upon request, we will provide, without charge, to each person, including any beneficial owner, to whom a copy of this prospectus is delivered, a copy of the documents incorporated by reference into this prospectus but not delivered with the prospectus. You may request a copy of these filings, and any exhibits we have specifically incorporated by reference as an exhibit in this prospectus, at no cost by writing or telephoning us at the following address: Inhibikase Therapeutics, Inc., 1000 N. West Street, Suite 1200, Wilmington, Delaware 19801, Attention: Investor Relations, or by telephone request to 302-295-3800.

You may also access these documents, free of charge on the SEC’s website at www.sec.gov or on our website at http:www.inhibikase.com. Information contained in, or that can be accessed through, our website is not incorporated by reference in this prospectus or any accompanying prospectus supplement, and you should not consider it part of this prospectus or any accompanying prospectus supplement. We have included our website solely as an inactive textual reference.

This prospectus is part of a registration statement we filed with the SEC. We have incorporated exhibits into this registration statement. You should read the exhibits carefully for provisions that may be important to you.

You should rely only on the information incorporated by reference or provided in this prospectus or any prospectus supplement. We have not authorized anyone to provide you with different information. We are not making an offer of these securities in any state where the offer is not permitted. You should not assume that the information in this prospectus or in the documents incorporated by reference is accurate as of any date other than the date on the front of this prospectus or those documents.

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46,091,739 Shares of Common Stock

Pre-Funded Warrants to Purchase up to 22,873,779 Shares of Common Stock

PROSPECTUS SUPPLEMENT

Joint Book-Running Managers

  Jefferies   BofA Securities   Cantor

Lead Managers

  LifeSci Capital   Oppenheimer & Co.

Co-Managers

H.C. Wainwright & Co. Ladenburg Thaimann

November 20, 2025

FAQ

What is Inhibikase Therapeutics (IKT) offering in this 424B5 prospectus?

Inhibikase is offering 46,091,739 shares of common stock and pre-funded warrants to purchase up to 22,873,779 shares of common stock. The pre-funded warrants are exercisable at an exercise price of $0.001 per share and do not expire.

What are the pricing terms for Inhibikase Therapeutics (IKT) stock and pre-funded warrants?

The public offering price is $1.45 per share of common stock and $1.449 per pre-funded warrant, reflecting the share price minus the $0.001 exercise price of each pre-funded warrant.

How much cash will Inhibikase Therapeutics (IKT) receive from this offering and how will it be used?

Before expenses, the company expects $99,997,127 in gross proceeds and about $93.6 million in net proceeds. It plans to use the funds, together with existing cash, mainly for clinical trials and development of IKT‑001 for PAH, other research and development, potential technology or business acquisitions, and general corporate purposes.

How does this offering affect dilution for existing Inhibikase (IKT) shareholders?

Based on a net tangible book value of $0.97 per share as of September 30, 2025 and the $1.45 offering price, the company estimates an immediate dilution of about $0.07 per share to investors buying in this offering. Additional dilution may occur if outstanding options, warrants, and the pre-funded warrants are exercised or if further equity is issued.

Will Inhibikase Therapeutics (IKT) receive proceeds when the pre-funded warrants are exercised?

The pre-funded warrants have an exercise price of $0.001 per share. The company notes it will receive only nominal additional proceeds, if any, upon exercise, particularly if holders elect cashless exercise.

How long will the new funding support Inhibikase Therapeutics’ operations?

Inhibikase estimates that the net proceeds from this offering, combined with $77.3 million in cash, cash equivalents and marketable securities as of September 30, 2025 and potential proceeds from exercising certain existing warrants, will be sufficient to fund operating and capital needs into 2029.

Is there a public market or listing for the Inhibikase pre-funded warrants?

No. The pre-funded warrants will not be listed on Nasdaq or any other national securities exchange or recognized trading system, and the company does not expect a public trading market to develop for them.