Vinay Prasad has stepped down as head of the FDA’s biologics division just two months into the job, following growing backlash over how he handled Sarepta’s Elevidys, the only approved gene therapy for Duchenne muscular dystrophy.

Sarepta's therapy has been under scrutiny from regulators after two teenage boys died earlier this year from acute liver injury, a known side effect of the treatment. The FDA then requested a pause in shipments of the drug after the death of a third patient taking a different Sarepta therapy.

The Food and Drug Administration has paused distribution of the gene therapy Elevidys following the death of a third patient receiving treatment for muscular dystrophy. Alison and William Small are urging the agency to restore access to the drug,