The Food and Drug Administration is convening a meeting of outside experts on Tuesday to review exa-cel, a CRISPR-based treatment for sickle cell disease made by Vertex Pharmaceuticals and CRISPR Therapeutics.

Tuesday’s meeting is set up a bit differently than most FDA advisory panels. The agency has not raised any concerns about exa-cel’s efficacy or safety, and there will not be a typical vote at the end of the day on whether the data from exa-cel’s pivotal clinical trial support an approval as a treatment for sickle cell disease.

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Instead, the FDA is seeking input about the methods used by Vertex and CRISPR Therapeutics to evaluate the risk of inadvertently making unwanted changes to patients’ DNA — so-called off-target editing — when exa-cel is administered.

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