The FDA is considering revoking authorization of Pfizer’s COVID-19 vaccine for healthy children under 5, leaving many without a shot. Pfizer is in talks with the agency to keep authorization in place. Moderna’s vaccine is approved for children with health conditions. Novavax’s shot has never been available for children under 12.

The potential move comes as U.S. health agencies shift immunization policies under the leadership of Robert F. Kennedy Jr., a vaccine skeptic. The FDA’s decision is not related to the safety or efficacy of Pfizer’s vaccine. Moderna is working to increase supplies of its COVID shot for children.

Kennedy has previously petitioned to revoke authorization of mRNA vaccines. The CDC no longer recommends COVID vaccines for healthy children and pregnant women, but allows it if deemed necessary by a doctor. Pfizer and Moderna’s vaccines use messenger RNA technology.

Novavax’s protein-based shot has never been available for children under 12. The CDC’s guidance on COVID vaccines during pregnancy has shifted from a recommendation to “No Guidance/Not Applicable.” Pfizer’s vaccine remains authorized for children ages 6 months to 4 years.

Read more at CNBC: FDA may pull authorization of Pfizer Covid shot for children under 5