In closely watched developments ahead of next week’s meeting of the Centers for Disease Control and Prevention (CDC) vaccine advisory panel, the CDC today posted a draft meeting agenda, which adds hot-button topics that have become common talking points of vaccine critics.
Last week Health and Human Service secretary Robert F. Kennedy, Jr., scrapped the CDC’s 17-member Advisory Committee on Immunization Practices (ACIP) and a few days later replaced them with 8 new members, some of whom are closely aligned with his anti-vaccine views. It’s unclear if Kennedy will add any more members to the group.
An earlier Federal Register notice said ACIP would meet virtually June 25 through June 27, with plans to discuss a wide range of vaccines, including those for COVID-19. It was expected to vote on recommendations for COVID-19, human papilloma virus (HPV), influenza, and meningococcal vaccines, as well as respiratory syncytial virus (RSV) vaccines for adults, and RSV vaccine for maternal and pediatric populations. It was also slated to hold related votes for the Vaccines for Children program. The notice included the caveat that the agenda items are subject to change as priorities dictate.
The draft agenda posted today reflects a shortened 2-day meeting, with input from a few CDC scientists and one from Sanofi Pasteur, who will discuss the safety and immunogenicity of Flublok for older children and adolescents.
Thimerosal and MMRV topics raise eyebrows
The agenda also includes two topics that haven’t recently been the focus of ACIP work groups and discussions, thimerosal as a vaccine ingredient and measles, mumps, rubella, varicella (MMRV) vaccine in children younger than 5 years old. The agenda doesn’t say who will present data on the two topics.
Thimerosal is a vaccine preservative for multidose vials that was eliminated from most vaccines in 1999 as a precaution, despite no evidence of harm from the low levels included in vaccines, except for minor local reactions. Extensive research has found no link between thimerosal and autism. Currently, only a limited number of flu vaccines contains the preservative.
Jeremy Faust, MD, an emergency medicine physician with Brigham and Women's Hospital, wrote today in his Inside Medicine newsletter on Substack, that thimerosal has long been an obsession of the anti-vaccine movement, despite robust evidence of its safety. If the group votes to remove the ingredient, the step won’t improve vaccine safety but will undermine confidence in other vaccines, he added.
Regarding the MMRV vaccine discussion, the group will discuss its use in children younger than 5 years old and offer a proposed recommendation, though it doesn’t appear the group will vote on it. The MMRV vaccine is a live-attenuated product that is typically administered to children ages 12 months to 12 years old. The first dose is usually given between 12 and 15 months, with the second dose given between 4 to 6 years of age. The vaccine carries a slightly higher risk of febrile seizures when given as the first dose compared to separate measles, mumps, and rubella (MMR) and varicella vaccines, especially among younger children.
The added scrutiny of the MMRV vaccine on the ACIP agenda comes against the backdrop of brisk measles activity, fueled by multiple outbreaks, which has put the nation on pace to pass the record for the most cases since the United States eliminated measles in 2000.
Faust wrote that though the group isn’t expected to vote on the MMRV vaccine, the appearance of the topic on the meeting agenda is concerning.
Expected and conspicuously absent votes
Among the expected topics, the group will discuss a proposed recommendation for clesrovimab, a monoclonal antibody vaccine to prevent RSV in infants in their first season for the disease. The Food and Drug Administration (FDA) approved the shot, called Enflonsia, on June 9. Also, the group will discuss the flu vaccine, which typically follows FDA strain picks. However, the agenda reflects a separate vote on thimerosal-containing flu vaccines.
According to the agenda, the group is also expected to vote on RSV vaccines for maternal and pediatric populations.
Noticeably absent is a vote on COVID vaccine recommendations. In late May and without revealing the data to the public behind the decision, Kennedy announced that the CDC removed its COVID recommendations for healthy children and pregnant women.
