On December 9, 2025, concerns have arisen regarding the safety of approved therapies for treating respiratory syncytial virus (RSV) in infants. The FDA is reevaluating the safety of two approved drugs, Beyfortus by Sanofi and AstraZeneca, and Enflonsia by Merck, which are administered to infants in their early months to protect them from RSV complications.
RSV is a common virus that affects babies, especially during winter, leading to severe illness and even death in some cases. It is the leading cause of hospitalization among infants in the United States. To combat this, the CDC recommends pregnant individuals to receive an RSV vaccine between 32 and 36 weeks of pregnancy from September to January.
The recent scrutiny by federal health agencies, led by Secretary of Health and Human Services Robert F. Kennedy, Jr., a known vaccine skeptic, questions established vaccines and medications. This move follows a decision to rescind the recommendation for a universal birth dose of the hepatitis B vaccine, despite objections from experts.
Reports suggest that FDA officials initiated an investigation into RSV therapies during the summer. Vaccine skeptics have raised concerns, unsupported by evidence, that these shots might increase the risk of seizures in infants.
In 2023, the FDA approved Beyfortus, an antibody drug, for infants at risk of severe RSV. Similarly, Enflonsia, another antibody drug, received approval in June 2025. Both drugs underwent rigorous clinical trials to ensure their safety and efficacy before being authorized for use.
As discussions continue around the safety of these RSV therapies, it is crucial to prioritize science-based decision-making to protect the health and well-being of infants. The ongoing scrutiny underscores the importance of thorough evaluation and monitoring of medications to ensure they meet the highest safety standards.
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