A new treatment available this fall could keep infants and some older babies with RSV out of the hospital and even out of the doctor’s office.
Nirsevimab, brand name Beyfortus, was developed by AstraZeneca in collaboration with Sanofi, and was approved last month by the U.S. Food and Drug Administration. It’s a long-acting monoclonal antibody product administered as a shot. Monoclonal antibodies are man-made proteins similar to the antibodies humans naturally produce, which help the body fight off infection.
The drug is designed to reduce severe disease, and has been shown to lower the risk of hospitalizations and health care visits for RSV in infants by about 80%, according to a recent news release by the U.S. Centers for Disease Control and Prevention.
When should babies get the new RSV shot?
The CDC recommends one dose of nirsevimab for infants younger than 8 months entering their first RSV season. Some children at high risk of severe outcomes from RSV—such as those who are severely immunocompromised, who were born prematurely, or who have chronic lung disease or significant congenital heart disease—will need a second dose between the ages of 8 and 19 months.
“This new RSV immunization provides parents with a powerful tool to protect their children against the threat of RSV,” new CDC Director Dr. Mandy Cohen said in the release. “RSV is the leading cause of hospitalizations for infants and older babies at higher risk, and today we have taken an important step to make this life saving product available.”
Nirsevimab will also help reduce the impact of the disease on the health care system, Dr. John Farley, director of the FDA’s Office of Infectious Diseases in the organization’s Center for Drug Evaluation and Research, said in a July news release on the agency’s approval of the drug.
What is RSV?
RSV is one of the most common childhood respiratory illnesses, typically infecting fall through the end of spring. While it causes only mild, cold-like symptoms for most, an estimated 50,000 to 80,000 kids under 5 years of age—most infants—are hospitalized annually due to the virus. Some require oxygen and IV fluids, and even mechanical ventilation. The virus kills an estimated 100 to 300 children under the age of 5 each year in the U.S.
“As we head into respiratory virus season this fall, it’s important to use these new tools available to help prevent severe RSV illness,” Cohen said in the release. “I encourage parents of infants to talk to their pediatricians about this new immunization and the importance of preventing severe RSV.”
Last year a so-called "tripledemic" of RSV, COVID, and flu overwhelmed pediatric hospitals in the U.S. and abroad. The same pattern could play out this year, experts warn, though new tools like nirsevimab could help squash the impact of the disease and protect hospital capacity.