(CMR) The Food and Drug Administration (FDA) has asked states to temporarily halt using Johnson & Johnson’s Covid-19 vaccine after six people in the US developed a rare blood-clotting disorder. The FDA said the recommendation was “out of an abundance of caution.”
The cases occurred in women ages 18 to 48, with symptoms developing six to 13 days after receiving the shot.
“Right now, these adverse events appear to be extremely rare,” the FDA said in a joint statement with the Centers for Disease Control and Prevention. “COVID-19 vaccine safety is a top priority for the federal government, and we take all reports of health problems following COVID-19 vaccination very seriously.”
FDA asked that people who have received the J&J vaccine who develop severe headache, abdominal pain, leg pain, or shortness of breath within three weeks after vaccination should contact their health care provider.
J&J said in a statement that “no clear causal relationship” has been identified between the blood clots and the vaccine and that it was working closely with regulators to assess the data. More than 6.8 million doses of J&J’s vaccine have been administered in the US.
CDC will convene a meeting of the Advisory Committee on Immunization Practices (ACIP) on Wednesday to further review these cases and assess their potential significance. FDA will review that analysis as it also investigates these cases.
The J&J/Janssen vaccine was 66.3% effective in clinical trials (efficacy) at preventing laboratory-confirmed COVID-19 illness in people who had no evidence of prior infection 2 weeks after receiving the vaccine. People had the most protection 2 weeks after getting vaccinated.