The groundbreaking approval has been eagerly anticipated by patients and doctors alike. The treatment is expected to be extremely expensive.

The Food and Drug Administration on Friday approved a powerful treatment for sickle cell disease, a devastating illness that affects more than 100,000 Americans, the majority of whom are Black.

The therapy, called Casgevy, from Vertex Pharmaceuticals and CRISPR Therapeutics, is the first medicine to be approved in the United States that uses the gene-editing tool CRISPR, which won its inventors the Nobel Prize in chemistry in 2020.

“I think this is a pivotal moment in the field,” said Dr. Alexis Thompson, chief of the division of hematology at Children’s Hospital of Philadelphia, who has previously consulted for Vertex. “It’s been really remarkable how quickly we went from the actual discovery of CRISPR, the awarding of a Nobel Prize, and now actually seeing it being an approved product.”