Unapproved in US for decades, levosimendan stumbles in phase 3 as Tenax eyes narrow FDA path

Tenax's Phase 3 LEVEL trial of oral levosimendan in PH-HFpEF missed both primary and key secondary endpoints.

The primary endpoint was 6-minute walk distance (6MWD), with a 3.5-meter placebo-adjusted improvement that was not statistically significant (p=0.63).

The key secondary endpoint, Kansas City Cardiomyopathy Questionnaire (KCCQ), also failed to reach significance.

In a prespecified subgroup of patients with greater disease burden (baseline walk distance <333 meters), there was a 26.3-meter placebo-adjusted improvement, but these results are nominal and not adjusted for multiple testing.

Tenax plans to request a Type C meeting with the FDA to discuss a narrow regulatory path, potentially focusing on more severely affected patients, and to seek parallel feedback from the EMA.

Levosimendan has been unapproved in the U.S. for decades and previously failed to gain approval for other indications like acute decompensated heart failure and post-CABG low cardiac output syndrome, adding to regulatory challenges.