[8-K] TENAX THERAPEUTICS, INC. Reports Material Event

Rhea-AI Filing Summary

Tenax Therapeutics reported new clinical progress for its lead drug candidate TNX-103 in patients with pulmonary hypertension related to heart failure with preserved ejection fraction. A planned blinded sample size re-estimation for the LEVEL Phase 3 trial showed the study is powered at well over 90% to detect a 25 meter change in 6-minute walk distance, the primary measure of effectiveness. This supports keeping the existing enrollment target and previously communicated timelines for finishing enrollment and reporting topline data. Tenax also started LEVEL-2, a second global Phase 3 registrational trial of TNX-103 in the same patient population, indicating a broader late-stage development program.

Insights

Biopharma clinical development analyst

Tenax confirms strong Phase 3 trial power and starts a second registrational study.

The company reports that its LEVEL Phase 3 trial of TNX-103 is now confirmed, via a prespecified blinded sample size re-estimation, to be powered at well over 90% to detect a 25 meter change in 6-minute walk distance. High statistical power reduces the chance of missing a true treatment effect on this functional walking test, which is the primary endpoint in this pulmonary hypertension in HFpEF population.

Tenax also notes that it is keeping the previously announced enrollment target and timelines for completion of enrollment and topline data, suggesting the re-estimation did not require enlarging the trial. In parallel, it has initiated LEVEL-2, a second global Phase 3 registrational study of TNX-103 in the same indication. Together, these steps indicate the program is advancing through late-stage development, while eventual outcomes will depend on the clinical data readouts described.

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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 17, 2025

Tenax Therapeutics, Inc.

(Exact name of registrant as specified in its charter)

Delaware		001-34600		26-2593535
(State or other jurisdiction of incorporation)		(Commission File Number)		(IRS Employer Identification No.)

101 Glen Lennox Drive, Suite 300

Chapel Hill, NC 27517

(Address of principal executive offices) (Zip Code)

919-855-2100

(Registrant’s telephone number, including area code)

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:

☐	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, $0.0001 par value per share	TENX	The Nasdaq Stock Market LLC

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (17 CFR 230.405) or Rule 12b-2 of the Securities Exchange Act of 1934 (17 CFR 240.12b-2).

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 8.01 Other Events.

On December 17, 2025, Tenax Therapeutics, Inc. (the “Company”) issued a press release announcing that the prespecified Blinded Sample Size Re-estimation (BSSR) of LEVEL, an ongoing, registrational Phase 3 clinical trial evaluating TNX-103 (oral levosimendan) in patients with pulmonary hypertension in heart failure with preserved ejection fraction (PH-HFpEF) in the United States and Canada, demonstrated the trial is powered at well over 90% to detect a 25 meter change in 6-minute walk distance (6MWD), the primary endpoint. Based on these results, Tenax confirmed the previously announced target enrollment number and expected enrollment completion timeframe as well as topline data timeframe. The Company also announced that it has initiated its global Phase 3 LEVEL-2 study, the second registrational Phase 3 study of TNX-103 in patients with PH-HFpEF. A copy of the press release is attached hereto as Exhibit 99.1.

Item 9.01 Financial Statements and Exhibits.

(d) Exhibits

Exhibit No.		Description
99.1		Press Release dated December 17, 2025.
104		Cover Page Interactive Data File (embedded within the Inline XBRL document).

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SIGNATURES

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

Date: December 17, 2025	Tenax Therapeutics, Inc.
	By:	/s/ Christopher T. Giordano
		Christopher T. Giordano
		President and Chief Executive Officer

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