Merck has announced the US Food and Drug Administration (FDA) has approved sotatercept-csrk (Winrevair) for the treatment of adults with pulmonary arterial hypertension (PAH) to increase exercise capacity, improve World Health Organization (WHO) functional class (FC), and reduce the risk of clinical worsening events.
Winrevair was previously granted breakthrough therapy designation by the FDA. Winrevair is the first FDA-approved activin signalling inhibitor therapy for PAH, representing a new class of therapy that works by improving the balance between pro- and anti-proliferative signaling to regulate vascular cell proliferation underlying PAH.
“Pulmonary arterial hypertension is a rare, progressive and ultimately life-threatening disease in which blood vessels in the lungs thicken and narrow, causing significant strain on the heart,” said Marc Humbert (Université Paris-Saclay, Paris, France) and investigator on the Phase 3 STELLAR study. “Based on the Phase 3 STELLAR trial, adding Winrevair to background PAH therapy demonstrated significant clinical benefits compared to background PAH therapy alone. This approval is an important milestone, as it offers healthcare providers a novel therapeutic option that targets a new PAH treatment pathway.”
The approval is based on the Phase 3 STELLAR trial, which compared Winrevair (n=163) to placebo (n=160), both in combination with background standard of care therapies in adult patients with PAH (WHO Group 1 FC II or III). Results showed adding Winrevair to background therapy increased six-minute walk distance from baseline by 41 meters (95% confidence interval [CI]: 28, 54; p<0.001; placebo-adjusted) at week 24 and significantly improved multiple important secondary outcome measures, including reducing the risk of death from any cause or PAH clinical worsening events by 84% versus background therapy alone (number of events: 9 vs 42, hazard ratio=0.16; 95% CI: 0.08, 0.35; p<0.001).
Winrevair is given once every three weeks by subcutaneous injection and may be administered by appropriate patients or caregivers with guidance, training and follow-up from a healthcare provider.