Health Care

FDA limits use of J&J vaccine over rare blood clots

The Food and Drug Administration (FDA) on Thursday announced that it is limiting the authorization for the Johnson & Johnson COVID-19 to people who cannot or will not get other versions of the vaccine, citing the risk of rare blood clots.  

The authorization for the J&J vaccine, also known as the Janssen vaccine, is now limited to people for whom the Pfizer or Moderna vaccines “are not accessible or clinically appropriate,” or “who elect to receive the Janssen COVID-19 Vaccine because they would otherwise not receive a COVID-19 vaccine.” 

That is, people can still get the J&J vaccine if they are allergic to the mRNA vaccines from Pfizer or Moderna, or if personal concerns with the other vaccines mean they would otherwise go without any inoculation.  

The agency said it was making the decision after “conducting an updated analysis, evaluation and investigation of reported cases” of the blood clots, which “warrants limiting the authorized use of the vaccine.” 

Importantly, the Pfizer and Moderna vaccines do not carry the same risks of blood clots, given they use a different technology than the Johnson & Johnson vaccines.  


Blood clots also remain rare among J&J recipients. The FDA has identified 60 confirmed cases of the blood clots following receipt of the J&J vaccine and nine deaths, it said. That is about three cases of blood clots for every million J&J vaccines administered, and 0.48 deaths per million doses of the J&J vaccine. 

The blood clots are formally known as thrombosis with thrombocytopenia syndrome (TTS).  

This is not the first time that the risk has affected distribution of the vaccine. Regulators caused shockwaves, and some controversy, early last year, when they paused the administration of the J&J vaccine for several days to allow time to investigate the blood clots.  

“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, a top FDA official. “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 [authorization].” 

The J&J vaccine already had far lower usage than the Pfizer or Moderna vaccines. About 18 million doses have been administered, according to the Centers for Disease Control and Prevention, compared to more than 200 million for Moderna and more than 300 million for Pfizer.  

In making its decision, the FDA noted the availability of other vaccines from Pfizer and Moderna, “which provide protection from COVID-19 and have not been shown to present a risk for TTS.”