United Therapeutics Corporation (Nasdaq: UTHR) announced that The Lancet has published full results of its ADVANCE OUTCOMES phase 3 study evaluating ralinepag in patients with pulmonary arterial hypertension (PAH). The drug has not yet been approved by the U.S. Food and Drug Administration and remains investigational.

The randomized, double-blind, placebo-controlled study enrolled 687 PAH patients, 80% of whom were on dual background therapy and 70% of whom were classified as World Health Organization Functional Class II at baseline. Ralinepag reduced the risk of a clinical worsening event by 55% compared with placebo (hazard ratio 0.45, 95% CI [0.33–0.62]; p<0.0001), meeting the study's primary endpoint.

Ralinepag also met key secondary endpoints, showing a 24.3% reduction in NT-proBNP levels over placebo (p=0.0013) and a 20.4-meter placebo-corrected improvement in six-minute walk distance (p=0.0033) at week 28. The drug increased the odds of clinical improvement by 47% compared to placebo (p=0.015). Results were consistent across all patient subgroups.

The most commonly reported adverse events in the ralinepag group were headache, diarrhea, nausea, and myalgia, consistent with known prostacyclin pathway effects. No new safety signals were observed.

Vallerie V. McLaughlin, M.D., Chair of the ADVANCE OUTCOMES Steering Committee, said the findings "support ralinepag as an oral, once-daily prostacyclin pathway treatment option upon FDA approval." Dr. McLaughlin has received compensation as a consultant of United Therapeutics.

United Therapeutics submitted a New Drug Application for ralinepag to the FDA in June 2026.