It’s wonderful, but it will not solve the global health problem.
In severe cases, patients receive bone marrow transplants, a risky treatment that requires perfectly matched and very difficult to find donors. Although CRISPR treatment also requires a bone marrow transplant, it uses the patient’s own blood stem cells.
First, the blood stem cells were taken from the patient and the defective cells were destroyed by chemotherapy, much like with regular bone marrow transplants. Next, the researchers used CRISPR’s DNA cutting enzyme and guide RNA to break down BCL11A – a genetic switch that shuts down the fetal hemoglobin gene early in life. With this gene now reactivated, fetal hemoglobin is produced which restores the missing hemoblogin for beta-thalassemia patients and replaces the defective hemoglobin in sickle cell patients.
As a result, most of the patients in the trials produced sufficient amounts of fetal hemoglobin and no longer required blood transfusions. These include a teenager who can now swim painlessly, as well as a young man who hasn’t had blood transfusions for two and a half years after needing them regularly before, according to Boston Children’s Hospital.
Researchers need to follow up for longer periods to make sure there are no side effects like cancer that can be caused by CRISPR. However, the bigger issue is the cost – although the team didn’t mention the potential price of the treatment, a comparable gene therapy option without CRISPR can cost up to $ 1.8 million per patient, including chemotherapy and hospital stay. This obviously excludes a lot of patients, especially in the United States where health care costs can be astronomical.
However, the National Institute of Health and the Bill and Melinda Gates Foundation are pumping up to several hundred million dollars into the technology in hopes of cutting costs. This could include new treatment methods that would eliminate the need for a bone marrow transplant. “It’s a big hairy goal … but we’ll get there,” said Donald Kohn, a researcher at the University of California Gene in Los Angeles.