MSD has received US Food and Drug Administration (FDA) approval for an updated indication of Winrevair (sotatercept-csrk) for injections of 45mg and 60mg for pulmonary arterial hypertension (PAH, World Health Organization [WHO] Group I).
The approval is based on data from the Phase III global, placebo-controlled, double-blind, multicentre, parallel-group Zenith trial.
The indication will now include the clinical worsening event components - hospitalisation, lung transplantation and death - for adults with PAH, and focuses on improved exercise capacity and WHO functional class.
In the Zenith trial, which evaluated 172 patients with PAH at high risk of mortality, Winrevair, when added to background therapy, showed a statistically significant 76% reduction in risk for major mortality and morbidity compared to placebo.
The study ended early after interim analysis confirmed strong efficacy. Participants have now been offered a long-term open-label follow-up on Winrevair.
Adverse effects observed in Zenith included epistaxis, infections, telangiectasia, diarrhoea, rash, elevated haemoglobin, gingival bleeding and erythema.
Median treatment was 435 days for Winrevair compared to 268 days in placebo. Discontinuation due to adverse events occurred in 1% on Winrevair and 5% on placebo.
MSD research laboratories global clinical development senior vice-president Dr Joerg Koglin stated: “MSD’s leadership in PAH research is anchored in a comprehensive clinical programme that continues to advance science and deliver meaningful evidence for physicians and patients.
“This approval represents another step forward in our mission to deliver on the promise of Winrevair, an activin signalling inhibitor with an indication recognising its impact to adult patients with PAH on the risk of clinical worsening events, including death, lung transplantation and PAH hospitalisation.”
In June 2025, MSD received approval for its anti-programmed death receptor-1 (PD-1) therapy, Keytruda (pembrolizumab), for adults with resectable locally advanced head and neck squamous cell carcinoma.
