U.S. regulators on Thursday strictly limited who can receive Johnson & Johnson’s Covid-19 vaccine due to a rare but serious risk of blood clots.
The Food and Drug Administration said the shot should only be given to adults who cannot receive a different vaccine or specifically request J&J’s vaccine. U.S. authorities for months have recommended that Americans starting their Covid-19 vaccinations use the Pfizer or Moderna shots instead.
FDA officials said in a statement that they decided to restrict J&J’s vaccine after taking another look at data on the risk of life-threatening blood clots within two week of vaccination.
The decision is the latest restriction to hit J&J’s one-dose vaccine, which has long been overshadowed by the more effective two shots from Pfizer and Moderna.
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In December, the Centers for Disease Control and Prevention recommended prioritizing the Moderna and Pfizer shots over J&J’s because of its safety issues. Previously U.S. officials had treated all three vaccines similarly because they’d each been shown to offer strong protection.
But follow-up studies have consistently shown lower effectiveness for J&J’s vaccine. And while the blood clots seen with J&J’s shot are rare, officials say they’re still occurring.
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