Sanofi: Beyfortus RSV Study Shows Benefits Extend Beyond First Season

Sanofi SA (SNY) announced new data from a phase 3 trial of Beyfortus (nirsevimab), showing protection against respiratory syncytial virus (RSV) in infants extends into a second RSV season. The results, presented at a medical conference, support Beyfortus as a single-dose preventive for RSV in infants and young children. In the trial, Beyfortus demonstrated sustained neutralizing antibody levels and efficacy through a second RSV season in infants born during the study. Sanofi said the findings reinforce Beyfortus's role in reducing RSV-related lower respiratory tract infections. The company is seeking expanded approval for Beyfortus, which is already approved for RSV prevention in infants and young children.