Study finds experimental gene therapy reverses sickle cell disease for years


According to a study, a single dose restored blood cells to their normal shape and eliminated the most serious complication of sickle cell disease for at least three years in some patients.
Four patients at New York-Presbyterian/Columbia University Irving Medical Center participated in the multicenter study, the first to report on such long-term outcomes of a sickle cell gene therapy. The study was conducted by John F. Tisdale, MD, senior investigator at the NIH’s National Heart, Lung and Blood Institute, as the corresponding author.
The single-dose therapy, tested on 35 adults and adolescents with sickle cell disease, essentially corrected the shape of the patient’s red blood cells, but also completely eliminated episodes of severe pain caused when rigid, crescent-shaped red blood cells clumped together and blocked blood vessels. The painful episodes often resulted in widespread organ damage.
“You cannot overstate the potential impact of this new therapy,” said Markus Y. Mapara, MD, PhD, professor of medicine at Columbia University Vagelos College of Physicians and Surgeons and a co-author of the study.
“People with sickle cell disease live in constant fear of the next pain crisis. This treatment could give people with this disease their life back. We hope this therapy will also be successful in younger patients so they can grow up without experiencing pain crises and live longer,” he added.
In sickle cell disease, the abnormal haemoglobin caused red blood cells to stiffen and adopt a spiky, sickle-like shape.
With the new gene therapy, called LentiGlobin, blood-forming stem cells are collected from the patient’s blood. Harmless lentiviruses are then used to deliver a modified copy of the beta-globin gene into the stem cells. When the cells are later reinfused into the patient, they take up residence in the bone marrow and start making healthy new red blood cells.
In the clinical trial, the therapy completely eliminated severe pain crises in the months following infusion (follow-up ranged from 4 to 38 months) — the longest period in which a gene therapy for sickle cell disease has been studied. (ANI)