First-in-class biologic approved for rare lung disease

The US Food and Drug Administration (FDA) has approved WINREVAIR ™ (sotatercept-csrk) for subcutaneous injection (45mg, 60mg) for adults with pulmonary arterial hypertension (PAH, World Health Organization [WHO] Group 1). 

According to Merck (MSD outside of the US and Canada), WINREVAIR is the first activin signalling inhibitor therapy authorised for PAH.

Clinical data has demonstrated that on top of background therapy, the biologic significantly improved exercise capacity compared to just background therapy. For instance, the treatment increased patient’s six-minute walk distance from baseline by 41 meters at Week 24.

By improving the balance between pro- and anti-proliferative signalling to regulate vascular cell proliferation underlying PAH, this means WINREVAIR represents a new class of therapy for PAH, according to Merck/MSD.

The benefit of WINREVAIR 

“Based on the Phase III 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,” stated Dr Marc Humbert, Professor of Medicine and Director of the Pulmonary Hypertension Reference Center at the Université Paris-Saclay and investigator on the Phase III STELLAR study.

Further findings from the Phase III trial

The FDA approval is based on results from the Phase III STELLAR trial. Adding WINREVAIR to background therapy was shown to provide an 84 percent risk reduction in death from any cause or PAH clinical worsening events, versus background therapy alone compared to placebo, Merck/MSD confirmed.

“Sotatercept added to background therapy has the potential to become a new standard of care option for patients with pulmonary arterial hypertension,” shared Dr Aaron Waxman, Executive Director of the Center for Pulmonary Heart Diseases at Brigham and Women’s Hospital and investigator on the Phase III STELLAR study.

Merck/MSD stated that WINREVAIR is the subject of a licensing agreement with Bristol Myers Squibb.

FDA grants Orphan Drug Designation to sotatercept