Context:

The FDA has approved a new monoclonal antibody therapy, Enflonsia, developed by Merck, aimed at protecting infants from the highly contagious respiratory syncytial virus (RSV), which is the leading cause of hospitalization in infants. Enflonsia is administered as a single 105-milligram shot and has shown to reduce RSV-related hospitalizations in infants by more than 84% in trials. The therapy also decreases the incidence of severe lower respiratory infections like pneumonia by over 60%. While Enflonsia represents a significant advancement in RSV prevention, its availability depends on the CDC's recommendation, which is pending due to the recent dissolution of the advisory committee. Meanwhile, existing preventive measures such as the Beyfortus antibody and prenatal vaccines have already contributed to lowered hospitalization rates in recent RSV seasons.

Dive Deeper:

• Enflonsia, a monoclonal antibody developed by Merck, has been approved by the FDA to prevent RSV infections in infants, providing protection throughout the entire RSV season with a single injection.

• The clinical trials reveal that Enflonsia significantly reduces RSV-related hospitalizations by more than 84% and lowers the occurrence of serious respiratory infections requiring medical attention by over 60% compared to a placebo.

• RSV is a common and highly contagious virus that affects nearly all children by the age of 2, with severe cases leading to hospitalizations in infants and posing a life-threatening risk to the very young and elderly.

• Despite the approval, Enflonsia's availability is contingent upon the CDC's recommendation, which is currently delayed due to the reconstitution of its Advisory Committee on Immunization Practices.

• Existing preventive measures such as the Beyfortus antibody and prenatal vaccines have already been effective in reducing RSV hospitalization rates among infants, as demonstrated in recent CDC studies, although supply shortages have been an issue.

• RSV remains a significant health challenge, with doctors emphasizing the urgent need for more preventive tools to manage the condition, which can lead to severe lower respiratory illnesses such as bronchiolitis and pneumonia.

• Dr. Dean Y. Li of Merck stresses the importance of Enflonsia in alleviating the healthcare burden caused by RSV, with hopes of making it available before the 2025-26 season to help protect vulnerable infants during the critical RSV period.