FDA Alert

FDA Approves First Monoclonal Injection to Prevent RSV in Infants, Toddlers

Jessica Ganga

The FDA has approved the first monoclonal injection for neonates, infants, and toddlers for the prevention of syncytial virus (RSV). Nirsevimab-alip—a monoclonal antibody—was approved for use in neonates and infants born during or entering their first RSV season and in children aged up to 24 months who are vulnerable to severe RSV disease through their second season of the disease.

Monoclonal antibodies are laboratory-made proteins that are meant to mimic the immune system’s ability to fight off viruses. A singular, intramuscular dose of nirsevimab-alip prior to or during the RSV system may offer protection during the virus’s season.

“RSV can cause serious disease in infants and some children and results in a large number of emergency department and physician office visits each year,” John Farley, MD, MPH, director of the Office of Infectious Diseases in the FDA’s Center for Drug Evaluation and Research, said in a press release. “Today’s approval addresses the great need for products to help reduce the impact of RSV disease on children, families and the health care system.”

The approval of nirsevimab-alip comes after three clinical trials to support its safety and efficacy, with each testing a single dose on infants and children aged up to 25 months against those treated with placebo. Overall, each study resulted in nirsevimab-alip providing a reduced risk of RSV when compared to placebo.

Reported adverse events include rash and injection site reactions. Nirsevimab-alip is not recommended for infants and children with a history of serious hypersensitivity reactions to the ingredients in the injection or any of its excipients.




FDA approves new drug to prevent RSV in babies and toddlers. News release. US Food and Drug Administration; July 17, 2023. Accessed July 24, 2023.