Merck (NYSE:MRK) has revealed that the FDA has accepted its biologics license application (BLA) for sotatercept, an investigational activin signaling inhibitor, as a potential therapy for adult patients dealing with pulmonary arterial hypertension (PAH) belonging to WHO Group 1. This application has been granted priority review status, and a final decision from the FDA is expected by March 26, 2024.
If approved, Merck’s sotatercept could offer a fresh treatment option for PAH patients, introducing a novel approach to managing this condition.
The BLA submission is supported by data from the phase III STELLAR study, which assessed the safety and efficacy of sotatercept as an add-on to the current standard of care for adults with PAH, comparing it to a placebo. The study successfully met its primary endpoint, demonstrating that sotatercept significantly improved exercise capacity, as measured by the 6-minute walk distance (6MWD), and achieved positive results in eight out of nine key secondary outcome measures.
PAH is a rare and progressive vascular disorder affecting the lung arteries and the right side of the heart, leading to elevated blood pressure in the pulmonary circulation. It places a significant burden on the heart, resulting in limited physical activity, heart failure, and reduced life expectancy. The five-year mortality rate for PAH patients is approximately 43%. Merck estimates that there are around 40,000 PAH patients in the United States.
Sotatercept is designed to target cellular signaling associated with vascular hyperproliferation and pathological remodeling, with the aim of treating PAH. The FDA has recognized the drug’s potential by granting it breakthrough therapy and orphan drug designations for the treatment of PAH.
Merck added sotatercept to its portfolio following the acquisition of Acceleron Pharma in 2021, and it is subject to a licensing agreement with Bristol Myers Squibb (BMY). Additionally, the acquisition included the anemia drug Reblozyl, which is being developed and commercialized through a global collaboration with Bristol Myers Squibb. Merck receives milestone and royalty payments from Bristol Myers based on Reblozyl product sales, which saw a 34% year-over-year increase, generating $440 million in the first half of 2023.
Notably, United Therapeutics (UTHR) is a significant player in the PAH treatment market, offering four drugs in the United States: Remodulin, Orenitram, Tyvaso, and Adcirca. Among these, Tyvaso is an inhaled formulation of treprostinil, while Remodulin is injectable. UTHR also markets Orenitram, the oral version of treprostinil, and Adcirca (tadalafil) tablets. UTHR achieved FDA approval for a dry powder inhalation formulation for Tyvaso in May of the previous year, leading to a 49% year-over-year increase in Tyvaso sales, generating $557.3 million in the first half of 2023.
Featured Image: Megapixl
