Tonix Pharmaceuticals (NASDAQ: TNXP) licenses TNX-4900 for neuropathic pain

Rhea-AI Filing Summary

Tonix Pharmaceuticals Holding Corp. licensed exclusive worldwide rights to TNX-4900, a small-molecule candidate for chronic neuropathic pain, from Rutgers University. TNX-4900 is a highly selective Sigma-1 receptor antagonist with nanomolar affinity (Ki = 7.5 nM) and more than hundred-fold selectivity over Sigma-2, intended as a non-opioid approach to treating neuropathic pain.

In preclinical models of diabetic and chemotherapy-induced neuropathic pain, TNX-4900 produced significant and durable reductions in pain behaviors after both acute and chronic dosing, without evidence of tolerance or motor impairment. The compound shows high blood-brain barrier penetration and oral bioavailability of approximately 28%. Tonix plans additional pharmacokinetic, formulation and safety studies to potentially support an Investigational New Drug application with the U.S. Food and Drug Administration.

Insights

Biotech pipeline analyst

Tonix adds an early-stage, non-opioid neuropathic pain candidate with encouraging animal data but still preclinical.

Tonix Pharmaceuticals has obtained exclusive worldwide rights to TNX-4900, described as a highly selective Sigma-1 receptor antagonist with nanomolar affinity (Ki = 7.5 nM) and strong selectivity over Sigma-2. The compound’s high blood-brain barrier penetration and oral bioavailability of approximately 28% are notable design features for a chronic pain therapy taken by mouth.

The disclosure emphasizes preclinical analgesic activity in multiple models of diabetic and chemotherapy-induced neuropathic pain, with significant and durable reductions in pain behaviors and no observed tolerance or motor impairment in these studies. This positions TNX-4900 as a potential non-opioid option within neuropathic pain, a setting where long-term safety and tolerability are important.

Toward development, Tonix plans expanded pharmacokinetic, formulation and safety studies to potentially support an Investigational New Drug application with the U.S. Food and Drug Administration. Future company communications may outline specific study designs and timelines as TNX-4900 progresses from preclinical work toward possible human testing.

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UNITED STATES 

SECURITIES AND EXCHANGE COMMISSION 

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934

Date of report (date of earliest event reported): December 16, 2025

TONIX PHARMACEUTICALS HOLDING CORP. 

(Exact name of registrant as specified in its charter)

Nevada	001-36019	26-1434750
(State or Other Jurisdiction  of Incorporation)	(Commission  File Number)	(IRS Employer  Identification No.)

26 Main Street, Chatham, New Jersey, 07928

(Address of principal executive offices) (Zip Code)

Registrant’s telephone number, including area code: (862) 799-8599

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below):

☐ Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425) 

☐ Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12) 

☐ Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b)) 

☐ Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

Title of each class	Trading Symbol(s)	Name of each exchange on which registered
Common Stock	TNXP	The NASDAQ Capital Market

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§ 230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§ 240.12b-2 of this chapter). 

Emerging growth company ☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Item 7.01 Regulation FD Disclosure.

On December 16, 2025, Tonix Pharmaceuticals Holding Corp. (the “Company”) announced that it licensed exclusive worldwide rights to its TNX-4900 product candidate for chronic neuropathic pain from Rutgers University. A copy of the press release which discusses this matter is furnished hereto as Exhibit 99.01 and incorporated herein by reference.

The information in this Item 7.01 of this Current Report on Form 8-K, including Exhibit 99.01 attached hereto, shall not be deemed “filed” for purposes of Section 18 of the United States Securities Exchange Act of 1934 (the “Exchange Act”) or otherwise subject to the liabilities of that section, nor shall they be deemed incorporated by reference in any filing under the United States Securities Act of 1933 or the Exchange Act, except as shall be expressly set forth by specific reference in such a filing.

Item 8.01. Other Events.

On December 16, 2025, the Company announced that it licensed exclusive worldwide rights to TNX-4900 (formerly known as PW507), a highly selective small-molecule Sigma-1 receptor (“S1R”) antagonist with demonstrated analgesic activity in multiple animal models of neuropathic pain, from Rutgers University. TNX-4900 showed analgesic efficacy in multiple pain models and a safety profile supporting its potential as a non-opioid approach to treating neuropathic pain. TNX-4900 was created from a structure-based drug design program led by Dr. Youyi Peng and Dr. William Welsh at Rutgers University that produced a series of potent and selective triazole-based S1R antagonists. The compound, which binds the human Sigma-1 receptor with nanomolar affinity (K_i = 7.5 nM), demonstrates more than a hundred-fold selectivity over the Sigma-2 receptor, and exhibits high blood-brain barrier penetration and favorable adsorption, distribution, metabolism and elimination properties, including oral bioavailability of approximately 28%. In preclinical models of diabetic and chemotherapy-induced neuropathic pain, TNX-4900 produced significant and durable reductions in pain behaviors after both acute and chronic dosing without evidence of tolerance or motor impairment. The Company plans to advance TNX-4900 through expanded pharmacokinetic, formulation, and safety studies to potentially support an Investigational New Drug application with the U.S. Food and Drug Administration.

Forward- Looking Statements 

This Current Report on Form 8-K contains certain forward-looking statements within the meaning of Section 27A of the Securities Act of 1933 and Section 21E of the Securities Exchange Act of 1934 and Private Securities Litigation Reform Act, as amended, including those relating to the Company’s product development, clinical trials, clinical and regulatory timelines, market opportunity, competitive position, possible or assumed future results of operations, business strategies, potential growth opportunities and other statement that are predictive in nature. These forward-looking statements are based on current expectations, estimates, forecasts and projections about the industry and markets in which we operate and management’s current beliefs and assumptions.

These statements may be identified by the use of forward-looking expressions, including, but not limited to, “expect,” “anticipate,” “intend,” “plan,” “believe,” “estimate,” “potential,” “predict,” “project,” “should,” “would” and similar expressions and the negatives of those terms. These statements relate to future events or our financial performance and involve known and unknown risks, uncertainties, and other factors which may cause actual results, performance or achievements to be materially different from any future results, performance or achievements expressed or implied by the forward-looking statements. Such factors include those set forth in the Company’s filings with the SEC. Prospective investors are cautioned not to place undue reliance on such forward-looking statements, which speak only as of the date of this press release. The Company undertakes no obligation to publicly update any forward-looking statement, whether as a result of new information, future events or otherwise. 

Item 9.01 Financial Statements and Exhibits.

(d)		Exhibit No.		Description.
		99.01 104		Press Release of the Company, dated December 16, 2025 Cover Page Interactive Data File (embedded within the Inline XBRL document)

SIGNATURE

Pursuant to the requirement of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized.

	TONIX PHARMACEUTICALS HOLDING CORP.
Date: December 16, 2025	By:	/s/ Bradley Saenger
	Bradley Saenger
	Chief Financial Officer

FAQ

What did Tonix Pharmaceuticals (TNXP) announce about TNX-4900?

Tonix Pharmaceuticals announced that it licensed exclusive worldwide rights to TNX-4900, a product candidate for chronic neuropathic pain, from Rutgers University.

What is TNX-4900 and how does it work for neuropathic pain?

TNX-4900 is a highly selective small-molecule Sigma-1 receptor antagonist with nanomolar affinity and more than hundred-fold selectivity over Sigma-2, being developed as a non-opioid approach to treating neuropathic pain.

What preclinical results for TNX-4900 did Tonix (TNXP) describe?

In preclinical models of diabetic and chemotherapy-induced neuropathic pain, TNX-4900 produced significant and durable reductions in pain behaviors after both acute and chronic dosing, without evidence of tolerance or motor impairment.

What development stage is TNX-4900 currently in?

TNX-4900 has shown activity in preclinical animal models. Tonix plans expanded pharmacokinetic, formulation and safety studies to potentially support an Investigational New Drug (IND) application with the U.S. Food and Drug Administration.

What rights did Tonix Pharmaceuticals (TNXP) obtain from Rutgers University?

Tonix licensed exclusive worldwide rights to the TNX-4900 product candidate for chronic neuropathic pain from Rutgers University.

Why is TNX-4900 considered a non-opioid approach to neuropathic pain?

TNX-4900 targets the Sigma-1 receptor as a highly selective antagonist rather than acting on opioid receptors, and is described as a potential non-opioid approach to treating neuropathic pain.

What are the key pharmacologic properties of TNX-4900 mentioned by Tonix?

TNX-4900 binds the human Sigma-1 receptor with nanomolar affinity (Ki = 7.5 nM), shows more than a hundred-fold selectivity over Sigma-2, exhibits high blood-brain barrier penetration, and has oral bioavailability of approximately 28%.