FDA, CDC call for pause in use of Johnson & Johnson vaccine after six reported cases of rare blood clots

Federal health officials on Tuesday called for a pause in the use of the Johnson & Johnson coronavirus vaccine, saying they are reviewing reports of six U.S. cases of a rare and severe type of blood clot in people after receiving the vaccine.

All six cases occurred among women between the ages of 18 and 48, and symptoms occurred six to 13 days after vaccination, according to a statement issued by the Food and Drug Administration and the Centers for Disease Control and Prevention.

The CDC will hold a meeting Wednesday of its Advisory Committee on Immunization Practices to review the cases and assess their potential significance, the statement said. The FDA will continue to investigate the cases.

“Until that process is complete, we are recommending a pause in the use of this vaccine out of an abundance of caution,” the statement said. “This is important, in part, to ensure that the health care provider community is aware of the potential for these adverse events and can plan for proper recognition and management due to the unique treatment required with this type of blood clot.”

The type of clot, called cerebral venous sinus thrombosis, was seen in combination with low levels of blood platelets, the agencies said. Treatment is different from what might typically be administered; while usually an anticoagulant called heparin is used to treat blood clots, it is dangerous to give heparin in this situation. Alternative treatments need to be given, they said.