Sickle Cell Disease Gene Therapies Using CRISPR Approach Possible FDA Approval

Sickle cell disease causes red blood cells to warp into crescent shapes that get stuck in blood vessels, leading to pain, organ damage, and possibly death.

Vertex Pharmaceuticals' exa-cel, developed with CRISPR Therapeutics, edits genes to treat sickle cell and could soon be the first CRISPR-based treatment approved by the FDA.

Exa-cel removes stem cells, uses CRISPR to snip out the mutated sickle cell gene, then returns the cells to the patient to produce normal hemoglobin.

The treatment requires chemotherapy and extended hospital stay, but did not have unwanted CRISPR gene edits in trials.

Competitor Bluebird Bio also has a sickle cell gene therapy awaiting potential FDA approval in December, but the high costs of these treatments is generating discussion.