FDA urged to publish follow-up studies on covid-19 vaccine safety signals

The FDA has been criticised for taking more than a year to follow up a potential increase in serious adverse events in elderly people receiving Pfizer’s covid-19 vaccine, Maryanne Demasi reports

In July 2021 the US Food and Drug Administration (FDA) quietly disclosed findings of a potential increase in four types of serious adverse events in elderly people who had had Pfizer’s covid-19 vaccine: acute myocardial infarction, disseminated intravascular coagulation, immune thrombocytopenia, and pulmonary embolism.1 Little detail was provided, such as the magnitude of the increased potential risk, and no press release or other alert was sent to doctors or the public. The FDA promised it would “share further updates and information with the public as they become available.”
Eighteen days later, the FDA published a study planning document (or protocol) outlining a follow-up epidemiological study intended to investigate the matter more thoroughly.2 This recondite technical document disclosed the unadjusted relative risk ratio estimates originally found for the four serious adverse events, which ranged from 42% to 91% increased risk. (Neither absolute risk increases nor confidence intervals were provided.) More than a year later, however, the status and results of the follow-up study are unknown. The agency has not published a press release, or notified doctors, or published the findings by preprint or the scientific literature or updated the vaccine’s product label.

The BMJ has also learnt that the FDA has not publicly warned of similar signals detected in a separate observational cohort study it conducted of the third dose (first booster dose) in the elderly3; nor has the agency publicly acknowledged other published observational studies or clinical trial reanalyses reporting compatible results. Experts spoke to The BMJ about their concerns about the data and have called on the FDA to notify the public immediately.
“To keep this information from the scientific community and prevent us from analysing it ourselves, is irresponsible. It presumes that these organisations are perfect and cannot benefit from independent scrutiny,” says Joseph Fraiman, an emergency medicine physician in New Orleans, who recently carried out a reanalysis of serious adverse events in Pfizer’s and Moderna’s randomised trials…

https://www.bmj.com/content/379/bmj.o2527