FDA Accepts Merck's Application to Expand Enflonsia Protection for High-Risk Infants

Merck's Enflonsia (clesrovimab-cfor) is one step closer to expanding its protection to high-risk infants during their second RSV season. The FDA has accepted a supplemental biologics license application (sBLA) for the treatment, which will now be reviewed by March 22, 2027.

The decision comes after an 84.3% drop in RSV hospitalizations among those treated with Enflonsia during their first season, as seen in a phase 3 trial. Macaya Douoguih, vice president of global clinical development at Merck Research Laboratories, said, 'For some children, the potentially serious impact of RSV does not stop after their first RSV season.'

The expanded indication would include infants under two years old who are at increased risk for severe RSV disease through their second season. This includes those with chronic lung disease or congenital heart disease.