Communications

(Oct. 10, 2025) – In its June 2025 meeting, the Centers for Disease Control and Prevention Advisory Committee on Immunization Practice recommended clesrovimab, a newly licensed and the second approved long-acting RSV monoclonal antibody, as an alternative to nirsevimab for infants under eight months old born during or entering their first RSV season who did not receive protection through maternal RSV vaccination. In June, the Food and Drug Administration approved clesrovimab (Enflonsia, Merck), the second long-acting RSV monoclonal antibody, for preventing RSV-associated lower respiratory tract infections among infants. Clesrovimab is administered as a single intramuscular injection before or during an infant’s first RSV season. In its June meeting, ACIP recommended either clesrovimab or nirsevimab for preventing RSV-associated LRTI in infants under eight months old born during or entering their first RSV season who are not protected through maternal RSV vaccination. For more information, see the CDC report in Morbidity and Mortality Weekly Report summarizing the evidence for clesrovimab and providing updated clinical guidance for protecting infants against RSV-associated LRTI. As reported in the MMWR, hospitalization for RSV fell by half among babies under three months during the 2024-25 RSV season when these products became widely available compared to the 2018-20 RSV season.
--Karen Braman