Phase 3 trials now recruiting people with PH-HFpEF to test TNX-103
Two global studies will assess safety and walking ability outcomes
Two Phase 3 clinical trials are now recruiting participants to test Tenax Therapeutics‘ experimental therapy TNX-103 (oral levosimendan) in people with pulmonary hypertension associated with heart failure with preserved ejection fraction (PH-HFpEF).
Tenax said its ongoing Phase 3 trial, LEVEL (NCT05983250), is expected to finish enrollment next year. That trial is recruiting participants at sites across the U.S. and Canada. Tenax recently completed a blinded sample size re-estimation (BSSR), a statistical check built into the study design to confirm whether the trial has sufficient participants. The analysis supported proceeding with the planned enrollment of about 230 participants.
Enrollment progress supports Phase 3 study design
“We are very pleased with the outcome of the BSSR, a derisking element built into the LEVEL protocol from the start,” Chris Giordano, president and CEO of Tenax, said in a company press release.
“We are also very encouraged by the high rate of study completion in this assessment of the first two-thirds of patients in LEVEL,” Giordano added. “We look forward to sharing topline data in the second half of 2026 and remain confident in our ability to execute on our Phase 3 development plan of TNX-103.”
Tenax has also launched a second Phase 3 trial, called LEVEL-2 (NCT07288398), which is expected to recruit about 540 adults with PH-HFpEF at dozens of sites worldwide. One site in Texas is already recruiting participants.
“We have selected over 100 sites across 15 countries so far to participate in LEVEL-2,” said Stuart Rich, MD, chief medical officer of Tenax. “Relying on what we have learned from LEVEL, Tenax has implemented a rigorous process to identify sites globally whose method of assessing patient hemodynamics is consistent with the most successful sites in the U.S. and Canada. Our feasibility data suggests a total enrollment timeline of approximately two years.”
How the Phase 3 trials are designed
In both LEVEL and LEVEL-2, participants are randomly assigned to take TNX-103 or a placebo once daily. The main goal in both trials is to determine whether the therapy can improve 6-minute walk distance (6MWD), a common measure of exercise capacity in people who are able to walk. In a previous Phase 2 trial called HELP (NCT03541603), weekly infusions of levosimendan — the active agent in TNX-103 — were associated with improvements in 6MWD.
“LEVEL-2 includes a cohort of patients who will undergo a 6-month, blinded, placebo-controlled, safety observation following the 26-week efficacy assessment, to provide the FDA and other global regulators a robust safety database to support their ultimate risk/benefit analysis at the approval stage,” Rich said.
Tenax has also launched an open-label extension study in which patients who complete the Phase 3 trials may receive long-term TNX-103, with monitoring for safety and efficacy.
PH-HFpEF refers to high blood pressure in the lungs’ blood vessels in people whose left ventricle pumps blood normally but does not relax and fill properly between beats. This impaired filling causes pressure to build up and back into the lungs.
TNX-103 aims to treat the disease by prompting blood vessels to relax and making it easier for heart muscles to contract.
About the Author
