FDA Restricts Johnson & Johnson's COVID Vaccine Due To Blood Clot Risk

The Food and Drug Administration has placed new limits on the emergency use authorization for Johnson & Johnson's single-dose COVID vaccine because of concerns about thrombocytopenia syndrome (TTS), a rare syndrome that can cause potentially life-threatening blood clots.

The agency said that the Johnson & Johnson vaccine should only be given to adults who cannot receive a vaccine made by Moderna or Pfizer. Those who specifically request the Johnson & Johnson vaccine will still be able to get it.

"Today's action demonstrates the robustness of our safety surveillance systems and our commitment to ensuring that science and data guide our decisions," said Peter Marks, M.D., Ph.D., director of the FDA's Center for Biologics Evaluation and Research. "We've been closely monitoring the Janssen COVID-19 Vaccine and occurrence of TTS following its administration and have used updated information from our safety surveillance systems to revise the EUA. The agency will continue to monitor the safety of the Janssen COVID-19 Vaccine and all other vaccines, and as has been the case throughout the pandemic, will thoroughly evaluate new safety information."

Despite the risk of developing blood clots, the FDA said that the "potential benefits of the vaccine for the prevention of COVID-19 outweigh the known and potential risks."

Studies have shown that while Johnson & Johnson's vaccine is effective at preventing severe cases of COVID-19, it lags behind the protection offered by a two-dose series of vaccines made by Pfizer and Moderna, which have both been prioritized by the Centers for Disease Control and Prevention.