FDA Approves Beyfortus for Use in Infants With RSV

The FDA today approved Beyfortus (nirsevimab-alip) for prevention of respiratory syncytial virus (RSV). The medication would be used to help prevent RSV lower respiratory tract disease in babies and infants who are born during or are entering their first RSV season. The medication could also be used for infants 24 months and younger who are still vulnerable to RSV through their second season of RSV.

RSV is an acute respiratory disease that primarily affects young children and older adults. Lower respiratory tract disease is a possible effect of RSV infection in young children; these infections include pneumonia and bronchiolitis. Those most vulnerable to emergency department visits include premature infants and those who have chronic lung disease of prematurity or significant congenital heart disease. Children younger than 12 months make up about 1% to 3% of children hospitalized each year due to RSV in the United States. RSV has been found to be seasonal, with most cases coming in the fall.

“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. 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,” said John Farley, MD, MPH, director of the Office of Infectious Diseases in the FDA’s Center for Drug Evaluation and Research, in a statemnt from the FDA.

Beyfortus is a monoclonal antibody, which is a laboratory-made protein that mimics the ability of the immune system to fight off pathogens like viruses. The medication would be administered as a singular injection prior to or during the RSV season in the attempt to provide protection to infants.

Three clinical trials tested the efficacy and safety of the medication before the FDA approval, as well as the incidence of medically attended RSV lower tract infection (MA RSV LRTI) for 150 days after administration.

The first trial included 1453 preterm infants born during or entering their first RSV season. Of the 969 infants who received the single dose of Beyfortus, 2.6% experienced MA RSV LRTI vs 9.5% of infants on placebo. The second trial included 1490 term and late-preterm infants, of which 994 received Beyfortus; 1.2% of infants on Beyfortus were infected with MA RSV LRTI vs 5.0% in the placebo group. The last trial was randomized and double-blind and included 925 preterm infants and infants with chronic lung disease of prematurity or congenital heart disease. This study acted as the evidence for the use of the medication in this vulnerable population.

Rash and injection site reactions were found to be possible adverse events when using Beyfortus. Children with a history of severe hypersensitivity reactions to Beyfortus’ active ingredients should not be given the medication.

Reference

FDA approves new drug to prevent RSV in babies and toddlers. News release. FDA. July 17, 2023. Accessed July 17, 2023. https://www.fda.gov/news-events/press-announcements/fda-approves-new-drug-prevent-rsv-babies-and-toddlers