Monoclonal Antibody Protects Children from RSV

An extensive real-world study published in the Journal of Infection suggests that the long-acting monoclonal antibody nirsevimab (Beyfortus) provides protection against respiratory syncytial virus (RSV) infection for children younger than 2 years for up to one year.

Published on November 6, 2025, this study found RSV infection was confirmed in 8.5%, 8.0%, and 20.7% of children who received nirsevimab within 6 months, from 6 to 11 months, and beyond 12 months before RSV testing, respectively, while 16.6%, 17.7%, and 17.3% of those who didn't receive nirsevimab were infected in each corresponding period. 

These researchers wrote that the results of this study may stimulate discussions regarding repeated dosing schedules for infants and young children. 

Grants from the Japan Agency for Medical Research and Development and others supported this research.

Nirsevimab has been approved and is used in several countries, including the United States, to prevent RSV infections and their associated severe outcomes.