On July 17, 2023, the U.S. Food and Drug Administration (FDA) approved Beyfortus™ (nirsevimab-alip) injection. It is indicated to prevent lower respiratory tract disease caused by respiratory syncytial virus (RSV) for babies and toddlers. Given as one intramuscular (IM) dose, it will be used for babies born during or close to their first RSV season (usually late fall through early spring), and for toddlers up to two years old who are at risk for severe RSV disease through their second RSV season. Recommended doses are 50mg for babies who weigh less than 5kg (11 pounds) and 100mg for those weighing 5kg and over. Children who remain vulnerable through their second RSV season should receive 200mg. Beyfortus was developed by AstraZeneca, but Sanofi will market it in the United States. Distribution is expected to begin before the 2023 RSV season starts but after authorization from the Centers for Disease Control and Prevention’s (CDC) Advisory Committee on Immunization Practices (ACIP). The cost is not yet available. For complete prescribing information, look here.
u At a Glance
- Brand (Generic) Name: Beyfortus (nirsevimab-alip)
- Manufacturer: AstraZeneca/Sanofi
- Date Approved: July 17, 2023
- Indication: to prevent RSV lower respiratory tract disease for newborns, infants who are in their first RSV season, and at-risk toddlers younger than two years old who are in their second RSV season
- Dosage Forms Available: single-dose prefilled syringes containing 50mg/0.5mL or 100mg/mL for IM injection
- Launch Date: Fall 2023
- Estimated Annual Cost: Not yet announced
- Usually mild, RSV is highly contagious – generally affecting nearly all children at least once before they reach two years of age.
- However, according to statistics from the National Foundation for Infectious Diseases (NFID), RSV is responsible for over two million medical encounters (visits to doctors’ offices, urgent care or emergency rooms), up to 80,000 hospitalizations and 100 to 300 deaths annually for children under one year of age.
- Premature babies, infants up to six months old, and children who have chronic conditions, such as heart disease or an immune deficiency, are especially at risk. Members of certain ethnic groups, such as indigenous peoples, are more susceptible to severe RSV, as well.
- Before 2020, seasonal outbreaks of RSV were relatively predictable. Also like seasonal flu, RSV infections usually ramped up during the fall, peaked about the end of the calendar year, and then tapered off during spring. For the last few years, however, patterns have changed and more cases have occurred during the spring and summer months.
- In phase III clinical trial, Beyfortus lowered the risk of hospitalization for RSV by 60.2% and the need for medical care – including emergency room and urgent care visits – by 74.9%.
- In general, side effects, such as injection site reactions and rashes, were mild and temporary.
- Synagis® (palivizumab – Sobi) injection was approved by the FDA in 1998 to prevent serious lower respiratory tract infections caused by RSV in pediatric patients. For babies who have very high risk, the American Academy of Pediatrics (AAP) recommends up to five monthly doses of Synagis injected IM starting when RSV cases begin to increase during the child’s birth year. It should be administered by a health professional in a facility that is equipped to manage rare hypersensitivity reactions that may occur. Most children do not need to receive a second round of Synagis after their first birthday and Synagis is not indicated for initial use after a child turns two years old.
- In May 2023, two vaccines, Arexvy (respiratory syncytial virus vaccine, adjuvanted – GSK) suspension and Abrysvo™ (respiratory syncytial virus vaccine – Pfizer) solution, were FDA approved to prevent RSV for adults over the age of 60 years old. Abrysvo also is under FDA review, with an action date in August 2023, to protect babies up to six months old from RSV by vaccinating their mothers during pregnancy.
- Beyfortus was approved under the FDA’s FastTrack program.