Trial Shows Cheaper Bone Marrow Transplant Is As Effective as Gene Therapy for Sickle Cell Disease

A trial completed at Johns Hopkins and 20 other cancer centers in the U.S. and London showed that a bone marrow treatment process is a “viable and less costly alternative to recently approved gene therapy products for sickle cell disease.”

This type of transplant, which is called a “reduced-intensity haploidentical bone marrow transplantation,” involves marrow being given by a “half-matched” donor, usually from a family member of the patient. A half-matched donor means that “the proteins that help the body’s immune system function, and which are present on a donor’s marrow cells, must match at least half of those proteins on the recipient’s cells to be a good fit and to not attack the recipient’s body after the transplant.” Patients are treated with low doses of chemotherapy and given total body irradiation before the transplant. They are given drugs like cyclophosphamide (which helps prevent graft-versus-host disease) for up to a year after the procedure.

Of 42 people with severe sickle cell disease who had the procedure, “95% were alive two years after the transplant, and 88% are considered cured and are experiencing no disease-related events.” The trial also showed “very high engraftment of the donor cells and very high cure rates, the authors say.” This treatment costs a fraction of the price of gene therapy, and gene therapy also requires high dose chemotherapy, which many people cannot receive. Serious side effects were uncommon during the trial.

Transplantation also cuts hospital time for patients down to about eight days, compared to six to eight weeks for gene therapy. A review paper demonstrated that “the estimated cost of gene therapy is $2 million–$3 million, compared to about $467,747 for a transplant.”