CDC Advisory Panel Recommends Merck's New RSV Antibody Amid Controversy

The Centers for Disease Control and Prevention's (CDC) Advisory Committee on Immunization Practices (ACIP) has endorsed Merck's newly approved respiratory syncytial virus (RSV) antibody, Enflonsia, for use in infants. The recommendation, however, comes amid significant changes to the panel's composition and ongoing debates about vaccine policy.

ACIP Endorsement and Recommendation Details

In a 5-2 vote, the reconstituted ACIP recommended Enflonsia for infants younger than 8 months who are born during or entering their first RSV season and whose mothers did not receive a maternal RSV vaccine. This recommendation aligns with that of Sanofi and AstraZeneca's Beyfortus, a similar antibody product that has been on the market for two years.

Enflonsia, which received FDA approval in early June, demonstrated 85% efficacy in clinical trials at reducing the risk of hospitalization from RSV-related illness. RSV infections are a leading cause of hospitalizations in newborns, with 58,000 to 80,000 children under 5 years old hospitalized annually due to RSV-related illnesses.

Controversy Surrounding ACIP Restructuring

The endorsement comes in the wake of significant changes to the ACIP. Health and Human Services (HHS) Secretary Robert F. Kennedy Jr. recently dismissed the panel's previous 17 members and appointed new advisors, some of whom have expressed skepticism about established vaccine science. This move has sparked pushback from medical associations, including the American Academy of Pediatrics, which announced it would no longer work with the panel to develop vaccine guidelines.

The newly formed panel spent considerable time questioning the evidence supporting continued use of COVID-19 vaccines without new randomized, controlled trials. This approach has raised concerns about the potential influence of Kennedy's long-held anti-vaccine beliefs on the committee's recommendations.

Dissenting Voices and Industry Response

The two dissenting votes came from Retsef Levi, a professor at the MIT Sloan School of Management, and Vicky Pebsworth, a research director at the National Vaccine Information Center. Levi expressed concerns about deaths in clinical trials of babies who had received Enflonsia or Beyfortus, while Pebsworth voiced discomfort over adding another new shot to the combination of vaccines commonly given to children in the U.S.

Despite these objections, other panel members, such as Cody Meissner, a professor of pediatrics at the Dartmouth Geisel School of Medicine, strongly defended the antibody drugs, calling them a "spectacular accomplishment" with potentially enormous public health impact.

Merck has announced that Enflonsia will be available to order in July, ahead of the typical fall to winter pattern of RSV infections. Richard M. Haupt, Merck's head of global medical & scientific affairs for vaccines and infectious diseases, stated that the committee's recommendations are "an important step forward in efforts to help reduce the significant burden RSV continues to place on infants, families, and health care systems."