In patients with a baseline 6MWD below the trial median of 333 meters, treatment with TNX-103 resulted in a 26.3-meter improvement compared to placebo (p = 0.0112)

In the same patient population, TNX-103 produced a 47% reduction in NT-proBNP (p < 0.0001) and a 4.9 mmHg reduction in RVSP (p = 0.009) compared to placebo

With full statistics analysis now complete, Company confirms TNX-103’s biological effects include marked reductions in pulmonary artery pressure and NT-proBNP, a biomarker reflecting increased cardiac wall stress. Results will inform protocol population enrichment and changes to overall registrational path

CHAPEL HILL, N.C., Aug. 29, 2026 (GLOBE NEWSWIRE) -- Tenax Therapeutics, Inc. (Nasdaq: TENX) (“Tenax” or “Tenax Therapeutics” or the “Company”) today announced that additional results from the Phase 3 LEVEL clinical trial evaluating TNX-103 (oral levosimendan) in patients with pulmonary hypertension due to heart failure with preserved ejection fraction (PH-HFpEF) were presented in a Late-Breaking Clinical Science session at the European Society of Cardiology (ESC) Congress 2026 in Munich, Germany.

Data confirmed findings from prespecified analyses which identified a favorable treatment effect in patients with a lower baseline 6MWD, supported by consistent changes in prespecified endpoints measuring cardiac stress and pulmonary pressures.

“The independent analysis of LEVEL data we presented today sharpens what the earlier topline results initially indicated: patients with the lowest baseline walking distance had the greatest improvement, on top of state-of-the-art background therapy. What was particularly striking was that even patients who did not show a significant improvement in exercise capacity had the same magnitude of reduction in cardiac wall stress and pulmonary artery pressures, changes that correspond to a reduction in heart failure hospitalizations over longer follow-up,” said Sanjiv Shah, MD, Director of the HFpEF Program at Northwestern University Feinberg School of Medicine and LEVEL’s Principal Investigator. “The magnitude of the reduction in NT-proBNP and the accompanying lowering of pulmonary pressure indicate that TNX-103 may provide clinical benefit to the majority of patients with PH-HFpEF independent of its effect on walk distance. The data are compelling and consistently point toward a potential therapeutic benefit in PH-HFpEF patients.”

“The full set of prespecified analyses we completed in the last week, and Dr. Shah’s presentation of the results today, continue to emphasize that the treatment effect of TNX-103 is concentrated in patients walking less than the trial median of 333 meters at baseline. The finding of biologic efficacy in the majority of patients in LEVEL validates that the unique mechanism of action demonstrated in the Phase 2 HELP study can address patient function. That gives us conviction and a clear strategy to enrich LEVEL-2 for a study population of patients in whom the treatment effect is demonstrable,” said Stuart Rich, MD, Chief Medical Officer of Tenax Therapeutics. “LEVEL has been enormously informative in shaping what comes next, and we intend to move quickly on behalf of patients who currently have no approved treatment options.”

Key Takeaways from Late-Breaking Presentation

The Phase 3 LEVEL clinical trial (NCT05983250) randomized 241 patients with PH-HFpEF across 41 sites in the United States and Canada. In this population, the primary endpoint of change in 6-minute walk distance (6MWD) at Week 12 did not achieve statistical significance, nor did the key secondary endpoint, change in Kansas City Cardiomyopathy Questionnaire total symptom score (KCCQ-TSS); however, marked improvements were noted in exploratory endpoints that demonstrate the biologic effects of the therapy, notably N-terminal pro-B-type natriuretic peptide (NT-proBNP) and right ventricular systolic pressure (RVSP).

Several key observations made in the trial, and their potential influence on the future development of levosimendan for patients with pulmonary hypertension and heart failure, were emphasized:

  • Across the overall trial population (n = 241), TNX-103 was safe and well tolerated, with no significant arrhythmias.
  • This population of older, symptomatic patients presented with multiple comorbidities, and was well-treated on guideline-directed medical therapy (GDMT): across these categories of increasing disease severity, with emphasis placed on atrial fibrillation and exercise tolerance, and increasing therapeutic intervention like MRAs/diuretics, and SGLT-2 inhibitors, levosimendan’s benefit appears to increase.
  • An inverse linear relationship between baseline 6MWD and treatment effect was described and demonstrated not to be explained by regression to the mean. Patients in LEVEL whose baseline 6MWD match those reported in HELP and the recent CADENCE trial with sotatercept (274-285 meters) demonstrated an approximate 20-meter placebo-adjusted improvement in 6MWD. The overall trial population in LEVEL, however, had a median about 50-60 meters higher than in these previous PH-HFpEF trials.
  • Prognostic implications include the impact of levosimendan on NT-proBNP compared to multiple classes of heart failure therapies, including some currently being tested, with commentary of the magnitude of effect in relation to heart failure events. As noted in the presentation, no data from a Phase 3 randomized trial has demonstrated even half the impact on this key indicator of cardiac wall stress, when compared to placebo. In an analysis of the relationship between heart failure outcomes and NT-proBNP change across these classes, Dr. Shah noted that the magnitude of levosimendan’s effect on cardiac wall stress suggests potential impact on outcomes in these HFpEF patients.
  • In addition to RVSP, many echocardiographic endpoints show improvement with levosimendan compared to placebo. Across each domain of echocardiography, approximately 20 echocardiographic parameters improved, even when adjusting for multiple comparisons.

Dr. Shah referenced these results in the prespecified subgroup of patients with a baseline 6MWD below the trial median of 333 meters (n = 119), at Week 12:

  • 6MWD: least-squares mean change was +23.7 meters on TNX-103 versus −2.6 meters on placebo; treatment difference of +26.3 meters (p = 0.0112).
  • KCCQ-TSS: change was +9.8 points on TNX-103 versus +4.1 points on placebo; a 5-point threshold is generally considered clinically meaningful.
  • RVSP: change of −4.4 mmHg on TNX-103 versus +0.5 mmHg on placebo; treatment difference −4.9 mmHg (p = 0.009). (post-hoc analysis)
  • NT-proBNP: geometric least-squares mean ratio of 0.53 from baseline on TNX-103 (p < 0.0001), corresponding to a 47% reduction compared to placebo. (post-hoc analysis)

The Company intends that the LEVEL-2 population be enriched on the basis of clear evidence provided by the LEVEL results, and in a manner consistent with longstanding FDA guidance for sponsors. Tenax will continue to focus on the global development of this product for patients with high unmet need.

About Levosimendan (TNX-101, TNX-102, TNX-103)

Levosimendan is a novel, first-in-class K-ATP channel activator/calcium sensitizer currently being evaluated to treat pulmonary hypertension (PH) associated with heart failure with preserved ejection fraction (PH-HFpEF). Levosimendan was first developed for intravenous use in hospitalized patients with acutely decompensated heart failure, and it has received market authorization in 60 countries in this indication, although it is not available in the United States or Canada. Tenax’s Phase 2 HELP study, including its open-label extension stage, demonstrated the potential of IV (TNX-101) and oral (TNX-103) levosimendan to bring durable improvements in exercise capacity and quality of life, as well as other clinical assessments, in patients with PH-HFpEF. TNX-103 (oral levosimendan) is currently being evaluated in LEVEL-2, a Phase 3, double-blind, randomized, placebo-controlled clinical trial in patients with PH-HFpEF.

About Tenax Therapeutics

Tenax Therapeutics, Inc. is a Phase 3, development-stage pharmaceutical company using clinical insights to develop novel cardiopulmonary therapies. The Company owns global rights to develop and commercialize levosimendan, which it is developing for the treatment of PH-HFpEF, the most prevalent form of pulmonary hypertension globally, for which no product has been approved to date. For more information, visit www.tenaxthera.com . Tenax Therapeutics’ common stock is listed on The Nasdaq Stock Market LLC under the symbol “TENX”.

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Except for historical information, all of the statements, expectations and assumptions contained in this press release are forward-looking statements. These forward-looking statements may include information concerning our clinical data, our regulatory plans, our future trial designs, and our possible or projected future business operations. Actual results might differ materially from those explicit or implicit in the forward-looking statements. Important factors that could cause actual results to differ materially include: risks of our clinical trials, including, but not limited to, the results of such trials, and the design, timing, delays, costs, location, initiation, and enrollment of any future trials; any delays in regulatory review and approval of product candidates in development; risks regarding the formulation, production, marketing, customer acceptance and clinical utility of our product candidates;   risks related to our business strategy, including the prioritization and development of product candidates; reliance on third parties, including Orion Corporation, our manufacturers and CROs; our estimates regarding the potential market opportunity for our product candidates; cash usage and runway may not be within management’s expected ranges; the potential advantages of our product candidates; our competitive position; our ability to maintain our culture and recruit, integrate and retain qualified personnel and advisors, including our executives and members of our Board of Directors; risks associated with our cash needs; intellectual property risks; volatility and uncertainty in the global economy and financial markets in light of unexpected changes in tariffs and the possibility of pandemics, global financial and geopolitical uncertainties, including in the Middle East and the Russian invasion of and war against the country of Ukraine; changes in legal, regulatory and legislative environments in the markets in which we operate, and the impact of these changes on our ability to obtain regulatory approval for our products; and other risks and uncertainties set forth from time to time in our SEC filings. Tenax Therapeutics assumes no obligation and does not intend to update these forward-looking statements except as required by law.

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