GSK Seeks FDA Approval to Expand Arexvy RSV Vaccine Use to At-Risk Adults Under 50

British pharmaceutical company GSK has submitted an application to the U.S. Food and Drug Administration (FDA) seeking to extend the approved use of its RSV vaccine, Arexvy, to include at-risk adults aged 18 to 49.

If granted, this expanded indication would allow GSK to compete more directly in the under-50 age group with rival vaccines — Moderna’s mRESVIA and Pfizer’s Abrysvo — in the world’s largest pharmaceutical market.

Respiratory syncytial virus (RSV) is a common seasonal virus that can cause serious respiratory illness, especially in infants, older adults, and high-risk individuals. It is a leading cause of pneumonia and respiratory-related hospitalizations.

Currently, Arexvy is approved in the U.S. for adults aged 60 and older, as well as for at-risk adults aged 50 to 59. Although GSK was first to secure FDA approval in the RSV vaccine space, it has since lost market momentum to competitors, with declining sales reported.

GSK noted that the FDA is expected to issue a decision on the expanded indication in the first half of 2026. A similar review by European regulators is also underway, with outcomes anticipated within the same timeframe.