GSK US FDA oks Arexvy for adults 18-49

GSK plc (LSE/NYSE: GSK) announced that the U.S. Food and Drug Administration (FDA) has accepted for review a supplemental Biologics License Application to expand the indication of its RSV vaccine, Arexvy, to adults aged 18–49 with increased risk of severe respiratory syncytial virus (RSV) infection. The vaccine is currently approved for individuals aged 60 and older and those aged 50–59 with elevated risk factors. The sBLA is supported by phase IIIb trial data, which demonstrated non-inferior immune responses and consistent safety profiles in adults aged 18–49 compared to those aged 60 and older. The trial enrolled 1,458 participants across six countries, including 16 U.S. sites, with co-primary endpoints focused on RSV-A and RSV-B neutralization titers.

RSV affects an estimated 64 million people globally annually, with 21 million U.S. adults under 50 having at least one risk factor, such as COPD, asthma, or heart disease. The most common adverse reactions reported in the trial included fatigue, myalgia, arthralgia, and headache. A regulatory decision from the FDA is expected in the first half of 2026, with GSK also pursuing expanded indications in the European Economic Area and Japan.

The vaccine, containing recombinant RSV glycoprotein F and GSK's AS01E adjuvant, has been approved in over 60 countries for adults aged 60 and older. If approved, the expanded indication could broaden market access for a population representing 17% of U.S. adults aged 20–49.