Johnson & Johnson asked rival COVID-19 vaccine makers to probe clotting risks

The U.S. federal health agencies had on Tuesday recommended pausing use of Johnson & Johnson's vaccine for at least a few days after six women under the age of 50 developed rare blood clots after receiving the shot.

Last week, European regulators said they were reviewing rare blood clots in four recipients of the J&J shot in the United States, after which, the WSJ report said, the company began to reach out to other vaccine makers.