OnKure Therapeutics Announces Oversubscribed $150 Million Private Placement to Advance Next-Generation PI3Kα Pan-Mutant Selective Inhibitor Candidates in Breast Cancer and Vascular Anomalies

Rhea-AI Summary

OnKure Therapeutics (Nasdaq: OKUR) raised approximately $150 million in an oversubscribed private placement led by Access Biotechnology to advance two next‑generation PI3Kα pan‑mutant inhibitors, OKI‑345 (breast cancer) and OKI‑355 (vascular anomalies).

The company plans IND submissions for both programs in 1H 2027, expects to extend cash runway into 2029, and will add Liam Ratcliffe to its board.

Positive

• $150M gross proceeds from private placement
• Planned IND filings in 1H 2027 for OKI‑345 and OKI‑355
• Expected cash runway into 2029 from net proceeds
• Completed enrollment: OKI‑219 dose escalation n=38
• Completed enrollment: OKI‑219 + fulvestrant n=33

Negative

• Issuance of 26,713,636 common shares and 9,430,959 pre‑funded warrants
• Securities not registered for public resale; resale restrictions apply
• Company not pursuing further independent development of OKI‑219 now

Key Figures

Private placement size: $150 million Common shares sold: 26,713,636 shares Common share price: $4.15 per share +5 more

8 metrics

Private placement size $150 million Gross proceeds from oversubscribed private placement

Common shares sold 26,713,636 shares Class A common stock in private placement at $4.15 per share

Common share price $4.15 per share Purchase price for Class A common stock in private placement

Pre-funded warrants 9,430,959 warrants Pre-funded warrants sold in lieu of common at $4.1499 each

Pre-funded warrant price $4.1499 per warrant Purchase price per pre-funded warrant

Warrant exercise price $0.0001 per share Exercise price for pre-funded warrants, immediately exercisable

OKI-219 monotherapy n 38 patients Single-agent OKI-219 dose escalation in PIKture‑01

OKI-219 + fulvestrant n 33 patients OKI-219 + fulvestrant dose escalation in PIKture‑01

Market Reality Check

Price: $4.59 Vol: Volume 642,185 vs 20-day ...

high vol

$4.59 Last Close

Volume Volume 642,185 vs 20-day average 240,792 (relative volume 2.67x) indicates elevated trading interest ahead of the financing. high

Technical Price $4.595 is trading above the 200-day moving average of $2.81 and is within $0.305 of the 52-week high of $4.90.

Peers on Argus

OKUR is up 14.75% while key biotech peers show mixed to negative moves (e.g., AN...

1 Up

OKUR is up 14.75% while key biotech peers show mixed to negative moves (e.g., ANTX -1.91%, ITRM -1.68%, KZR -2.01%), indicating a stock-specific reaction to the private placement news.

Historical Context

3 past events · Latest: Mar 12 (Neutral)

Pattern 3 events

Date	Event	Sentiment	Move	Catalyst
Mar 12	Earnings and update	Neutral	+7.4%	Q4 2025 results, cash of $59.1M, PIKture‑01 enrollment and data timing.
Nov 06	Earnings and update	Neutral	-7.0%	Q3 2025 cash of $70.3M, runway into Q4 2026, PIKture‑01 progress.
Nov 04	Investor conferences	Neutral	-3.2%	Participation in multiple healthcare investor conferences with webcast access.

Pattern Detected

Recent news has produced mixed but generally moderate price reactions, with earnings updates sometimes drawing positive moves and sometimes pullbacks.

Recent Company History

Over the past several months, OnKure has focused on PI3Kα-targeted oncology development and funding visibility. On Nov 6, 2025, Q3 2025 results highlighted cash of $70.3M funding operations into Q4 2026 and progress in the PIKture‑01 trial. A Nov 4, 2025 conferences announcement had a modest negative impact. On Mar 12, 2026, Q4 and full‑year 2025 results reported cash of $59.1M and a Q4 net loss of $13.5M, alongside enrollment milestones and expectations for updated PI3Kα data. Today’s private placement extends that capital-focused trajectory.

Regulatory & Risk Context

Active S-3 Shelf · $200,000,000

Shelf Active

Active S-3 Shelf Registration 2025-11-06

$200,000,000 registered capacity

An effective S-3 shelf filed on Nov 6, 2025 allows OnKure to offer up to $200,000,000 of various securities, including an at‑the‑market program for up to $15,986,792 of Class A common stock through Leerink Partners. The current private placement is a separate transaction but occurs alongside this existing capital-raising framework.

Market Pulse Summary

This announcement details an oversubscribed private placement yielding approximately $150 million in...

Analysis

This announcement details an oversubscribed private placement yielding approximately $150 million in gross proceeds to fund two next‑generation PI3Kα pan‑mutant programs, OKI‑345 and OKI‑355, with planned IND filings in the first half of 2027. It also updates enrollment in the PIKture‑01 trial and clarifies that OKI‑219 will not be advanced independently for now. Investors may watch for mature PIKture‑01 data, IND submissions, and subsequent financing or shelf usage as key milestones.

Key Terms

pi3kα, investigational new drug, pre-funded warrants, pharmacokinetics, +2 more

6 terms

pi3kα medical

"next-generation PI3Kα pan-mutant inhibitors for breast cancer and vascular anomalies"

PI3Kα is a specific form of an enzyme that acts like a cellular switchboard controlling signals for cell growth, survival and movement; think of it as a traffic controller that helps decide when cells divide or stay alive. It matters to investors because drugs that block or modify this enzyme can slow tumor growth or cause side effects, so clinical trial results, approvals or safety concerns around PI3Kα-targeting therapies can significantly affect company value.

investigational new drug regulatory

"plans to submit an Investigational New Drug (IND) application to the U.S. Food and Drug"

An investigational new drug is a medication that is still being tested in clinical trials to determine if it is safe and effective for treating a specific condition. For investors, it represents a potential breakthrough that could lead to a new treatment and significant financial gains if successful, but also carries risks since it has not yet been approved for widespread use.

pre-funded warrants financial

"pre-funded warrants to purchase 9,430,959 shares of Common Stock at a purchase price"

Pre-funded warrants are financial instruments that give investors the right to purchase a company's stock at a set price, but with most or all of the purchase price paid upfront. They function like a coupon or gift card for stock, allowing investors to buy shares later at a fixed price, which can be beneficial if they want to avoid future price increases. This makes them important for investors seeking flexibility and certainty in their investment plans.

pharmacokinetics medical

"evaluating the safety, tolerability, pharmacokinetics, pharmacodynamics, and efficacy of OKI-219"

Pharmacokinetics is the study of how a substance, such as a drug or chemical, moves through and is processed by the body over time. It tracks how it is absorbed, distributed, broken down, and eventually eliminated. For investors, understanding pharmacokinetics helps gauge the effectiveness, safety, and potential risks of new medications or treatments, which can influence a company’s success and valuation in the healthcare industry.

pharmacodynamics medical

"evaluating the safety, tolerability, pharmacokinetics, pharmacodynamics, and efficacy of OKI-219"

Pharmacodynamics is how a drug actually affects the body — the strength, type and duration of its effects and the relationship between dose and response. Think of it like how turning a thermostat changes room temperature: it shows what the drug does and how much is needed to get the desired effect. Investors care because these properties drive clinical success, dosing convenience, safety profile and competitive advantage, all of which influence commercial potential and regulatory approval.

phase 1a/1b medical

"first-in-human phase 1a/1b study evaluating the safety, tolerability, pharmacokinetics"

Phase 1a/1b are the earliest human clinical trial stages that test a new drug’s safety, how the body handles it, and the right dosage. Think of phase 1a as a careful test drive in healthy volunteers to find safe dosing, and phase 1b as expanded testing—often in people with the target condition—to confirm dosing and look for early signs the treatment works; investors watch these stages because they determine safety, dosing decisions, and the next funding or development milestones.

AI-generated analysis. Not financial advice.

-- Financing led by Access Biotechnology with participation from new and existing investors

-- Financing to support advancement of two next-generation PI3Kα pan-mutant inhibitors for breast cancer and vascular anomalies – expect to file INDs for each program in 1H 2027

-- Liam Ratcliffe Joins OnKure’s Board of Directors

BOULDER, Colo., March 27, 2026 (GLOBE NEWSWIRE) -- OnKure Therapeutics, Inc. (Nasdaq: OKUR), a clinical-stage biopharmaceutical company focused on developing novel precision medicines, today announced that it has entered into a securities purchase agreement for a private placement with certain institutional and accredited healthcare investors, raising gross proceeds of approximately $150 million.

OnKure intends to use the net proceeds from the private placement to fund the preclinical and clinical development of its next-generation PI3Kα pan-mutant-selective inhibitor candidates in breast cancer and vascular anomalies, as well as for working capital and general corporate purposes. The private placement is being led by new investor, Access Biotechnology, with participation from other new and existing investors, including BVF Partners LP, RA Capital Management, Trails Edge Capital Partners, Coastlands Capital, StepStone Master G, L.P., Vivo Capital, ADAR1 Capital Management, Foresite Capital, Adage Capital Partners LP, Vestal Point Capital, Acorn Bioventures, Logos Capital and Prosight Capital.

“This transformational financing enables us to advance the development strategy for our next‑generation PI3Kα pan‑mutant selective inhibitor candidates, which represent a defining phase of our mutation‑selective strategy. We appreciate the significant commitment by the participating specialist biotech investors who believe in the potential of our PI3Ka pan-mutant portfolio,” said Nicholas Saccomano, Ph.D., President and Chief Executive Officer of OnKure. “We believe the clinical experience generated from the PIKture‑01 trial provided important validation of our approach to selectively targeting PI3Kα while avoiding class‑limiting toxicities predictably seen by insufficiently selective inhibitors. These insights directly informed the design of our pan‑mutant programs, defining the high bar attributes of our molecules. With the additional capital raised through this private placement, we are focused on leveraging our chemistry platform and clinical insights into PI3Kα signaling into differentiated, next-generation candidates for breast cancer and vascular anomalies, with the goal of delivering medicines that offer meaningful improvements in efficacy and tolerability for patients.”

Next-Generation PI3Kα Pan-Mutant Programs

The portfolio includes two next-generation PI3Kα pan-mutant programs, OKI-345 in breast cancer and OKI-355 in vascular anomalies. These candidates are designed to selectively inhibit mutant PI3Kα while sparing wildtype PI3Kα, potentially enabling a wider therapeutic index and avoidance of class-limiting toxicities. High and sustained target coverage across all hotspot PI3Kα mutations can support the potential for deep and durable responses, both as monotherapy and in combination regimens. The pan-mutant candidates are designed to have minimal drug-drug interaction potential, supporting broad combinability with current standards of care. Together with a commanding intellectual property estate, OnKure believes it is well positioned to address a significant unmet need across various PI3Kα-driven indications.

PI3Kα mutations represent the most common driver alterations in key subtypes of vascular anomalies, where PIK3CA variants lead to dysregulated signaling that promotes abnormal cell growth, proliferation, and survival. OnKure believes that OKI-355 has significant potential to address this large and underserved patient population as a differentiated systemic chronic therapy.

OnKure plans to submit an Investigational New Drug (IND) application to the U.S. Food and Drug Administration (FDA) for each of OKI‑345 and OKI‑355 in the first half of 2027.

PIKture‑01 Trial and OKI-219 Update

The PIKture-01 trial is a global, multi-center, dose-escalation, first-in-human phase 1a/1b study evaluating the safety, tolerability, pharmacokinetics, pharmacodynamics, and efficacy of OKI-219 as monotherapy and in combination with other anti-cancer drugs for the treatment of HR+ and HER2+ advanced breast cancer. As of March 26, 2026, the PIKture-01 trial has completed enrollment in single-agent OKI-219 dose escalation (n=38) and OKI-219 + fulvestrant dose escalation (n=33). Phase 2 dose evaluation in the OKI-219 + tucatinib and trastuzumab triplet and the OKI-219 + ribociclib and fulvestrant triplets will be completed in 2026. Given the progress of the Company’s PI3Kα pan-mutant inhibitors, OnKure is not planning to pursue further clinical development of OKI-219 independently at this time. Mature data from PIKture-01 will be presented by the end of the year.

Additional information about PIKture-01 may be found at www.ClinicalTrials.gov, using Identifier: NCT06239467.

Private Placement and Appointment of Liam Ratcliffe to Board of Directors

Pursuant to the terms of the securities purchase agreement, OnKure has agreed to sell an aggregate of 26,713,636 shares of its Class A common stock (“Common Stock”) at a purchase price of $4.15 per share and, in lieu of Common Stock, pre-funded warrants to purchase 9,430,959 shares of Common Stock at a purchase price of $4.1499 per pre-funded warrant. The pre-funded warrants have an exercise price of $0.0001 per share and will be immediately exercisable. The private placement is expected to close on March 31, 2026, subject to satisfactory closing conditions. With the net proceeds from the private placement, OnKure expects to extend its cash runway into 2029.

In conjunction with the financing, Liam Ratcliffe, M.D., Ph.D., Head of Biotechnology, Access Biotechnology will join OnKure’s Board of Directors. Andrew Phillips, Ph.D., OnKure’s Chairman of the Board of Directors, commented, “we are grateful for the commitment of our new and existing investors to the growth of OnKure. We are very pleased to welcome Liam to our Board of Directors. Liam is a well-respected leader who brings a remarkable track record of accomplishment to our Board.”

Leerink Partners is acting as lead placement agent for the financing. Evercore ISI, LifeSci Capital, and Oppenheimer & Co. are serving as co-placement agents for the financing.

The offer and sale of the foregoing securities are being made in a transaction not involving a public offering. The securities being issued and sold in the private placement have not been registered under the Securities Act of 1933, as amended (Securities Act), or any state securities laws, and may not be reoffered or resold in the United States except pursuant to an effective registration statement or an applicable exemption from the registration requirements of the Securities Act. The Company has agreed to file a registration statement with the Securities and Exchange Commission registering the resale of the shares of Common Stock and the Common Stock issuable upon exercise of the pre-funded warrants, in each case sold under the terms of the securities purchase agreement.

This press release shall not constitute an offer to sell or a solicitation of an offer to buy these securities, nor shall there be any sale of these securities in any state or other jurisdiction in which such offer, solicitation or sale would be unlawful prior to the registration or qualification under the securities laws of any such state or other jurisdiction.

About OnKure Therapeutics

OnKure Therapeutics (Nasdaq: OKUR) is a clinical-stage biopharmaceutical company focused on the discovery and development of best-in-class precision medicines that target biologically validated drivers of cancers and other diseases that are underserved by available therapies. Using a structure-based drug design platform, OnKure is building a pipeline of small molecule drugs designed to achieve optimal efficacy and tolerability by selectively targeting specific mutations shown to be key drivers of cancer and other diseases. OnKure aims to become a leader in targeting oncogenic PI3Kα and has multiple programs designed to enable best-in-class targeting of this key oncogene.

Cautionary Note Regarding Forward-Looking Statements

This press release contains forward-looking statements that involve substantial risks and uncertainties. All statements other than statements of historical facts contained in this press release are forward-looking statements. Such forward-looking statements include, among other things, statements regarding the completion and expected timing of the closing and gross proceeds received by OnKure in the private placement, OnKure’s expected use of net proceeds from the private placement, OnKure’s expected cash runway, OnKure’s ability to leverage insights from the PIKture-01 trial, the addition of Dr. Liam Ratcliffe to OnKure’s Board of Directors, the potential of, and expectations regarding, OnKure’s product candidates and programs, including OKI-219 and the pan-mutant programs; OnKure’s ability to advance additional programs; the expected milestones and timing of such milestones, including additional data for OKI-219 from the PIKture-01 trial, details on the pan-mutant program and the timing of the submission of the IND applications for OKI-345 and OKI-355; and statements by OnKure’s President and Chief Executive Officer. In some cases, you can identify forward-looking statements by terminology such as “expect,” “estimate,” “intend,” “may,” “plan,” “potentially,” “will” or the negative of these terms or other similar expressions.

These forward-looking statements are based largely on OnKure’s current expectations and projections about future events and trends that OnKure believes may affect its financial condition, results of operations, business strategy and financial needs. These forward-looking statements are subject to a number of risks, uncertainties and assumptions, including, among other things: market, market risks and other market conditions; the risk that the conditions to the closing of the private placement are not satisfied; OnKure’s limited operating history; the significant net losses incurred since inception; the ability to raise additional capital to finance operations; the risk that actual uses of cash and cash equivalents differ from the assumptions underlying OnKure’s expected cash runway; the ability to advance product candidates through preclinical and clinical development; the ability to obtain regulatory approval for, and ultimately commercialize, OnKure’s product candidates; the outcome of preclinical testing and early clinical trials for OnKure’s product candidates, including the ability of those trials to satisfy relevant governmental or regulatory requirements and the potential that the outcome of preclinical testing and early clinical trials may not be predictive of the success of later clinical trials; OnKure’s limited resources; the risk of adverse events, toxicities or other undesirable side effects; potential delays or difficulties in the enrollment or maintenance of patients in clinical trials; the decision to develop or seek strategic collaborations to develop OnKure’s current or future product candidates in combination with other therapies and the cost of combination therapies; OnKure’s limited experience in designing clinical trials and lack of experience in conducting clinical trials; the substantial competition OnKure faces in discovering, developing, or commercializing products; OnKure’s ability to protect its intellectual property and proprietary technologies; developments relating to OnKure’s competitors and its industry, including competing product candidates and therapies; reliance on third parties, contract manufacturers, and contract research organizations; legislative, regulatory, political and economic developments and general market conditions; and those risks described in the section entitled “Risk Factors” in documents that OnKure files from time to time with the SEC, including our Annual Report on Form 10-K filed with the SEC on March 12, 2026 and any subsequent filings with the SEC. These risks are not exhaustive. New risk factors emerge from time to time, and it is not possible for OnKure’s management to predict all risk factors, nor can OnKure assess the impact of all factors on OnKure’s business or the extent to which any factor, or combination of factors, may cause actual results to differ materially from those contained in, or implied by, any forward-looking statements. You should not rely upon forward-looking statements as predictions of future events. Although OnKure believes that the expectations reflected in the forward-looking statements are reasonable, OnKure cannot guarantee future results, levels of activity, performance or achievements. Except as required by law, OnKure undertakes no obligation to update publicly any forward-looking statements for any reason after the date of this press release.

Contact:
Dan Ferry
LifeSci Advisors
daniel@lifesciadvisors.com

FAQ

How much did OnKure (OKUR) raise in the March 27, 2026 private placement?

OnKure raised approximately $150 million in the private placement. According to the company, proceeds will fund preclinical and clinical advancement of its PI3Kα pan‑mutant candidates and general corporate purposes.

When will OnKure (OKUR) file INDs for OKI‑345 and OKI‑355?

OnKure expects to file INDs for both candidates in first half 2027. According to the company, the filings support next‑generation PI3Kα pan‑mutant programs for breast cancer and vascular anomalies.

What shareholder impact results from OnKure's (OKUR) financing terms?

The financing includes sale of 26,713,636 shares and 9,430,959 pre‑funded warrants, which could dilute existing holders. According to the company, proceeds are intended to extend cash runway and advance development programs.

What is the status of the PIKture‑01 trial for OKI‑219 as of March 26, 2026?

PIKture‑01 completed single‑agent dose escalation (n=38) and OKI‑219 + fulvestrant dose escalation (n=33). According to the company, phase 2 dose evaluation triplets will complete in 2026 and mature data will be presented by year end.

Who led the private placement and what board change accompanied OnKure's (OKUR) financing?

The financing was led by Access Biotechnology, and Liam Ratcliffe (Head of Biotechnology, Access Biotechnology) will join OnKure's board. According to the company, this follows commitments from multiple specialist biotech investors.