CRISPR Eliminated Symptoms of Genetic Disease in 2 Patients
But it’s too soon to know if it’s a cure
Victoria Gray was used to the attacks of excruciating pain. They came regularly, more than a half-dozen times per year, and were a side effect of her sickle cell disease. But since receiving a revolutionary new gene-editing treatment in July that uses CRISPR, Gray has yet to have one of these painful episodes.
On Tuesday, CRISPR Therapeutics and Vertex Pharmaceuticals, the companies that are developing the experimental therapy, announced that Gray, as well as another patient suffering from a related genetic disorder called beta thalassemia, now appear to be free of disease symptoms after receiving the treatment.
The news comes on the heels of another report of CRISPR being used to treat three patients with advanced cancers. CRISPR has spurred hope that it could be a one-shot treatment — or possibly even a cure — for a wide range of diseases. And now scientists are putting that notion to the test in the first human experiments of the gene-editing technique.
Sickle cell anemia and beta thalassemia affect millions of patients around the world. Both diseases arise from mutations in the HBB gene, which provides instructions for making hemoglobin, a critical protein in the blood that helps transport oxygen throughout the body. In sickle cell disease, malfunctioning hemoglobin makes misshapen red blood cells that look like sickles — hence the name. In beta thalassemia, the body simply doesn’t make enough hemoglobin. Complications from the two diseases, like organ damage, can result in early death.
But the experimental treatment that Gray received at a Nashville hospital could change that. On Tuesday, CRISPR Therapeutics CEO Samarth Kulkarni told investors in a conference call that the companies’ experimental treatment “has the potential to be a curative approach” for patients with sickle cell disease and beta thalassemia.
To treat these diseases, scientists at the companies made a single genetic edit in patients’ cells. Doing so first involves withdrawing blood from patients, then isolating the blood-producing stem cells. Next, using CRISPR, scientists edit the diseased cells in the lab and then infuse the modified cells back into the…