MSD (known as Merck & Co., Inc., Rahway, N.J., USA [NYSE: MRK] in the United States and Canada) announced today that the Health Sciences Authority (HSA) of Singapore has approved WINREVAIR® (sotatercept), for the treatment of adults with pulmonary arterial hypertension (PAH, World Health Organization [WHO] Group 1; Functional Class [FC] II to III) to increase exercise capacity, improve WHO functional class, and delay disease progression. This will mark the first availability of this therapy in Asia.

The HSA’s approval of WINREVAIR® is based on safety and efficacy results from the Phase 3 STELLAR trial.

PAH is a rare, progressive and life-threatening blood vessel disorder characterised by the constriction of small pulmonary arteries and elevated blood pressure in the pulmonary circulation. WINREVAIR®, the first US-FDA-approved activin signalling inhibitor therapy for PAH, works by improving the balance between pro and anti-proliferative signalling to regulate vascular cell proliferation underlying PAH.

“The HSA’s approval of WINREVAIR® provides new hope for PAH patients in Singapore and across Asia,” said Dr Abdullahi Sheriff, Managing Director, MSD in Singapore, Malaysia & Brunei. “This approval is a testament to MSD’s commitment to leading-edge science and driving innovation that can help people affected by cardiovascular and rare diseases like PAH.”

Results from the Phase 3 STELLAR trial show that adding WINREVAIR® to background therapy increased six-minute walk distance from baseline by 41 metres at Week 24, and significantly improved multiple important secondary outcome measures, including 84 per cent reduction in the risk of death from any cause or PAH clinical worsening events compared to background therapy alone. It is administered once every three weeks by subcutaneous injection; it is intended for use under the guidance of a health care professional and may also be administered by patients or caregivers when considered appropriate and when they receive training and follow-up from the doctor.

“The approval of WINREVAIR® in Singapore marks a significant milestone in the treatment of PAH across Asia,” said Dr Ivan Su, Executive Director, Global Medical & Scientific Affairs Lead for Asia Pacific, MSD. “With WINREVAIR®, we are introducing a novel therapy that targets the underlying disease, offering a different approach to care. This is a major step forward in improving both the quality of life and long-term outcomes for patients suffering from this life- threatening condition.”

“Pulmonary Hypertension Singapore (PHSG) welcomes this important development, as we recognise the chronic and progressive nature of PAH and the debilitating symptoms that patients and caregivers live with,” said Mr David Lim, Chairperson of patient group PHSG. “The approval of WINREVAIR® offers the PAH community its first new treatment option in years. We plan to work closely with MSD in Singapore to continue to raise awareness of PAH and to facilitate access to innovative therapies such as WINREVAIR® where appropriate.”

As PAH remains a disease with high morbidity and mortality, the HSA’s approval of WINREVAIR® underscores its dedication to improving patient care and outcomes.

WINREVAIR® will be available for dispensing by select health care providers in Singapore by Q1 2025.

Images: Winrevair (header) and Envato