The US FDA has accepted for review a New Drug Application from United Therapeutics Corporation (Nasdaq: UTHR) for ralinepag, an investigational prostacyclin IP receptor agonist intended to treat pulmonary arterial hypertension (PAH). The agency has set a Prescription Drug User Fee Act (PDUFA) target action date of June 24, 2027.
The filing rests on results from the Phase III ADVANCE OUTCOMES study, in which ralinepag reduced the risk of a first clinical worsening event by 55% compared with placebo (hazard ratio 0.45, 95% CI [0.33–0.62]; p<0.0001) in 687 predominantly pre-treated patients. The trial population was notable for its relatively preserved baseline functional status — 70% of patients were World Health Organization Functional Class (WHO FC) II and 80% were on dual background therapy. Ralinepag also demonstrated statistically significant improvements in N-terminal pro-B-type natriuretic peptide (NT-proBNP; 24.3% reduction over placebo; p=0.0013) and six-minute walk distance (6MWD; +20.4 m placebo-corrected difference; p=0.0033), and increased the odds of clinical improvement by 47% (p=0.015). The full results were published in The Lancet in July 2026.
The safety profile was consistent with known prostacyclin-related adverse events — primarily headache, diarrhea, nausea, and myalgia — and the company said no new safety signals were observed.