July 1 (Bloomberg) -- A stem-cell transplant reversed sickle cell disease in adults, according to a study that offers a potential cure for the debilitating condition.
Half of those who had the transplant, which involved the patient and a sibling, also were able to stop taking immunosuppressant drugs without experiencing rejection or having the donor cells attack their body, research released today in the Journal of the American Medical Association showed. People undergoing stem-cell transplants usually must take immunosuppressants for the rest of their lives.
More than 90,000 people in the U.S. have sickle cell disease, a genetic disorder found mostly in people of African descent, according to the U.S. National Institutes of Health. The condition can cause severe pain, organ damage and stroke. Study author Matthew Hsieh said it’s too soon to say the researchers have found a cure as patients have been followed only for an average of 3 1/2 years, but he is optimistic.
“They’re sickle-cell free for now,” Hsieh, a staff clinician at the National Institute of Diabetes and Digestive and Kidney Diseases and the National Heart, Lung, and Blood Institute in Bethesda, Maryland, said today in a telephone interview. “We are cautiously optimistic they are cured.”
Children with sickle cell can receive a transplant that combines chemotherapy with stem cells, he said. Adults though are usually considered too sick for that treatment.
“For a lot of adults, the only option for them is a partial transplant like ours,” he said.
The study included 30 patients ages 16 to 65 years who received a transplant that combined their own stem cells and those of a sibling. All the patients had a sibling who was a full match at the white blood cell level, something that occurs about 20 percent of the time, Hsieh said.
Sickle cell disease was reversed in 26 patients, or 87 percent. Fifteen patients discontinued immunosuppressants one year after their transplant and didn’t experience rejection or have the donor cells attack their body, the study showed. Patients were enrolled from July 2004 to October 2013.
The research also found that following transplant, the patient’s use of narcotics for pain declined as did the rate of hospitalization. Lung function also improved, Hsieh said.
Allison King, who wrote an accompanying editorial, said future studies will need to examine if stem cells from partially matched siblings can be just as beneficial.
“It’s an exciting advancement for adults with sickle cell disease,” King, an assistant professor of pediatrics at Washington University School of Medicine in St. Louis, said today in a telephone interview. “It really offers adult patients with sickle cell disease with matched siblings hope that they can be cured from this disease and have great outcomes.”