The Food and Drug Administration plans to ask Sarepta Therapeutics Inc. to pause shipments of its Elevidys treatment after three deaths were linked to the company’s gene therapies, according to a person familiar with the matter.

The agency's scrutiny of Sarepta has sharpened since the deaths of two teenage boys earlier this year who had received Elevidys, a gene therapy approved in the United States to treat a muscle-wasting condition called Duchenne muscular dystrophy.

The company had previously halted shipments to certain older patients following the deaths of two teenagers treated with the therapy, Elevidys.