12 adult patients with sickle cell anemia were cured with stem cell transplant from healthy, tissue-matched siblings. Physicians from University of Illinois at Chicago applied a new technique that does not involve chemotherapy to prepare the patient for the transplant. The results of the phase I/II clinical trial are published online in the journal Biology of Blood & Marrow Transplantation.
Earlier, stem cell therapy has been applied mainly for children with sickle cell disease. For adults, who are often more weakened than children by the disease, chemotherapy was considered too risky as it would destroy not only the patient’s own bloodforming stem cells, but also the entire immune system of patients, thus leaving them vulnerable to infections.
In the new procedure, 13 patients have received immunosuppressive drugs just before the stem cell transplant as well as a very low dose of total body irradiation. Compared with chemotherapy, this treatment was much less harmful and with fewer potentially serious side effects.
The stem cell transplant was derived from the blood of a healthy sibling. To graft vs host disease, in which transplant cells from a donor are being rejected by the recipient's body, HLA matching was made to ensure tissue compatibility.
In all 13 patients, the transplanted cells successfully grafted in the bone marrow and produced healthy red blood cells. Only one patient who failed to follow the post-transplant therapy reverted to the original sickle cell condition. The remaining 12 patients had normal hemoglobin levels and improved cardiopulmonary function even one year after the transplantation. They reported less pain and improved overall health. Four patients were able to stop post-transplantation immunotherapy without transplant rejection or other complications.
Since the technique does not involve chemotherapy, it may be widely used in adult patients, thus bringing cure to tens of thousands of adults suffering from the disease.