Tenax Therapeutics' heart failure drug TNX-103 misses primary endpoint in Phase 3, shares plunge 85%

Tenax Therapeutics announced that its investigational heart failure drug TNX-103 failed to meet the primary efficacy endpoint in the Phase 3 LEVEL trial.

The trial, which enrolled patients with pulmonary hypertension associated with heart failure with preserved ejection fraction, showed a 14-meter improvement in six-minute walk distance versus 10.4 meters for placebo, a difference that was not statistically significant. Symptom-burden scores were also similar between groups.

Following the news, Tenax's stock dropped about 85% to $1.99. Analysts noted modest biomarker gains and encouraging signals in older and more severe patients, but described the overall readout as very disappointing.