Merck Seeks FDA Approval for Expanded Use of RSV Drug Enflonsia
Pharmaceutical company Merck has submitted a supplemental Biologics License Application (BLA) to expand its RSV drug, Enflonsia, for use in children under two years of age at increased risk for severe respiratory syncytial virus disease through their second RSV season.
The FDA has accepted the application and set a target action date of March 22, 2027. This comes after the European Medicines Agency (EMA) accepted an application for the same indication expansion in the EU in July.
Enflonsia received FDA approval in June 2025 and European Commission approval in April 2026 for prevention of RSV lower respiratory tract disease in infants during their first RSV season. The drug is administered without weight-based dosing, based on data from the Phase 3 SMART trial.