On May 5, 2026, The New York Times reported that the U.S. Food and Drug Administration had blocked the publication of several studies supporting the safety of widely used vaccines against COVID-19 and shingles. The studies were carried out by FDA scientists working with data firms to review millions of patient records, were funded with millions of dollars in public money, and found that serious side effects were rare. A Health and Human Services spokesperson confirmed to CNBC that the studies had been blocked.
According to the Times, as relayed by CNBC, FDA scientists were directed in October 2025 to withdraw two COVID vaccine studies that had already been accepted for publication in medical journals, and in February 2026 top FDA officials did not sign off on submitting study abstracts on Shingrix, a shingles vaccine, to a drug safety conference. One withdrawn study reviewed records of 7.5 million Medicare enrollees and was accepted by the peer-reviewed journal Drug Safety; its only “concerning outcome” was anaphylaxis in about 1 in 1 million Pfizer recipients, the Deseret News reported, citing the Times. Another, covering 4.2 million people ages 6 months to 64 years, found rare cases of fever-related seizures and heart muscle inflammation.
HHS defended the decision. Spokesman Andrew Nixon said the studies were withdrawn “because the authors drew broad conclusions that were not supported by the underlying data. The FDA acted to protect the integrity of its scientific process and ensure that any work associated with the agency meets its high standards.” On the shingles research, an HHS spokesperson said the study design “fell outside the agency's purview.”
Critics rejected that rationale. Former FDA principal deputy commissioner Janet Woodcock told The Guardian, as quoted by the Deseret News, that “there is a pattern here for not letting information out that might support the general safety of vaccines, with methodological rationales given by non-scientist spokespersons.”
CNBC described the move as the latest effort by the Trump administration to challenge vaccines: under HHS Secretary Robert F. Kennedy Jr., a prominent vaccine skeptic, federal health agencies have softened COVID shot recommendations, cut back research on vaccine development and attempted to overhaul the childhood immunization schedule.
Correction (October 2, 2026): an earlier version of this entry omitted HHS's stated reason for withdrawing the studies, which is now included. It also said the government was “actively destroying” its surveillance data; the studies were withheld from publication, not destroyed, and that language was removed, as was a statement that the studies were buried because their findings were politically inconvenient, which is an inference the reporting does not establish. We removed pattern claims that no source in this entry supports: Kennedy firing Peter Marks over refusing to edit safety data, the firing of all 17 ACIP members, six vaccines dropped from CDC recommendations, $500 million in canceled mRNA research, and an April 2026 HHS block on a CDC hospitalization study.