Clinical Trial results published on December 12 2021 in the New England Journal of Medicine show that a newly developed gene therapy coined "LentiGlobin" has been able to restore normal blood function in 35 sickle cell patients. Through this one-time procedure, these patients are now producing stable amounts of normal red blood cells containing healthy hemoglobin. Similarly, these patients have reported that they no longer suffer the sever pain attacks common with sickle cell disease.
In this therapy, stem cells are removed from a person's bone marrow, exposed to a virus that inserts into these stem cells a healthy copy of the functioning hemoglobin gene. Simultaneously as these procedure is being done, the patient is treated with chemotherapy to kill off their bone marrow. The lab-repaired stem cells are then implanted and the patient can start producing healthy hemoglobin and thus healthy red blood cells.
There are still some health concerns with this procedure however. One of the first patients ever treated with LentiGlobin developed leukemia five years after the procedure and died. While it is not concrete is LentiGlobin caused the leukemia, the safety of treated patients is always a top concern. As such for a while, this treatment will likely take much time to get approved by the U.S. Food and Drug Administration approval, and when approved, will likely be very expensive.