FDA approves first stem cell therapy to treat severe aplastic anemia
The U.S. Food and Drug Administration on Monday announced the approval of the first hematopoietic stem cell transplant therapy to treat patients with rare but severe aplastic anemia.
Omidubicel-onlv is allowed for patients 6 and older after reduced intensity conditioning, the FDA said in a news release.
Gamida Cell Inc., a leader in cell therapy innovation with headquarters in Boston and Israel, was the applicant. Ayrmid Ltd. is the British-headquartered parent company.
Omisirge production will take place in RoslinCT’s manufacturing facility in Hopkinton, Mass., beginning in two years, Ayrmid said.
By 2027, Omisirge has the potential to treat 2,000 to 2500 patients per year in the United States, Global Reach Health reported in 2023. The wholesale cost for a single, one-time treatment course of Omisirge is $338,000 and doesn’t include the cost of the transplant procedure or hospital stay.
In 2023, the FDA initially approved the therapy for hematological malignancy to Gamida as a “novel and supplementary transplant option,” for those 12 and older, the FDA said.
Pharmacy Times reported the FDA approved the application on Friday.
“This approval is revolutionary in the therapeutic landscape and fundamentally changes how we approach treatment for SAA, where earlier treatment has potential to alter one’s life course,” Dr. Vinay Prasad, chief medical and scientific officer and director of the FDA’s Center for Biologics Evaluation and Research, said. “Severe aplastic anemia is a rare blood disorder that can be fatal, and the FDA remains committed to expanding treatment options for patients with this disease.”
Aplastic anemia happens when bone marrow, a red, spongy material inside bones, stops making enough new red cells, white cells and platelets.
With SAA, cells are damaged, often because the immune system attacks them.
Without enough blood cells, patients are highly vulnerable. Symptoms can include fatigue, shortness of breath, pale skin, frequent or prolonged infections, and unexplained or easy bruising. SAA can develop slowly or suddenly.
Transplanted stem cells are an option, but matching a sibling donor is not always possible.
If a donor isn’t available, providers may seek the use of umbilical cord transplant to treat SAA, but limitations include delayed hematopoietic recovery and increased risks of infections.
With Omisirge stem cell therapy, donated cord blood stem cells have been chemically enhanced with nicotinamide, which is a form of vitamin B3, and then given to a patient to help restore their blood and immune system.
An ongoing open-label, single-center study of patients 6 and older was led by Dr. Richard Childs, of the National Heart, Lung, and Blood Institute at the National Institutes of Health.
“The approval of Omisirge is a significant step forward in the treatment options available for patients with a high unmet medical need,” Childs said. “Patients in the study with aplastic anemia were high risk, but had significantly better than expected outcomes and demonstrated remarkably fast and high rates of neutrophil engraftment. This was achieved with low rates of mild acute GVHD [graft-versus-host disease] and no chronic GVHD meaning the patients achieved a rapid return to a normal life.”
The study focused on 14 patients unable to respond to other therapies but who have demonstrated “significantly better than expected outcomes,” according to Childs.
Twelve patients achieved rapid neutrophil recovery, with a median time to recovery reported at 11 days in data presented at the 2025 American Society of Hematology Annual Meeting.
And just 16% of patients experienced mild acute graft-versus-host disease and no cases of severe acute GVHD or chronic GVHD.
Also, 94% were disease-free and overall survival rate, with 86% achieving red blood cell transfusion independence.
“Omisirge is a novel stem cell product from umbilical cord blood that will be able to offer a therapeutic option for patients with severe aplastic anemia who have limited options for stem cell transplant,” Dr. Megha Kaushal, acting deputy director of the CBER Office of Therapeutic Products and pediatric hematologist, said. “Omisirge will shorten time to neutrophil recovery which leads to shorter recovery times after transplant and may improve infection rates in this patient population.”
In July, Michael Lohberg, the coach of U.S. Olympic swimmer Dara Torres, was diagnosed with aplastic anemia. The Miami Herald reported Lohberg, was receiving care at NIH in Bethesda, Md.
In 2017, the Department of Veterans Affairs declared eight “presumptive conditions” linked by scientific evidence to contaminants at the U.S. Marines’ Camp Lejeune in North Carolina, including aplastic anemia.