Covid Vaccines Must be Watched for Two Months Before FDA Review

The FDA will require makers of Covid-19 vaccine candidates to monitor their clinical trial participants for a median of two months after administering their last shot, a top agency official said.

The agency could shorten the time frame before it will consider authorizing the vaccine depending on what the data shows, Peter Marks, director of the Food and Drug Administration’s Center for Biologics and Evaluation Research, said during a JAMA Live event Monday.

“We’re not going to be completely flexible. It’s not like we’re going to take anything. That would be dangerous. On the other hand, if it turns ...