FDA Greenlights Omidubicel-onlv for Severe Aplastic Anemia, Marking First Cell Therapy for the Rare Blood Disorder

On Friday, the FDA granted approval to omidubicel-onlv (Omisirge; Gamida Cell Inc), marking the first approved cell therapy specifically for the treatment of severe aplastic anemia (SAA). The approval addresses a critical unmet need for patients across the United States.¹

Omidubicel-onlv is approved for use in adults and pediatric patients aged 6 years and older following reduced intensity conditioning.² This new indication follows the drug’s initial FDA approval in 2023 for hematological malignancy, positioning it as a novel and supplementary transplant option.³

Understanding Severe Aplastic Anemia

SAA is characterized as a rare, life-threatening hematologic disorder in which bone marrow fails to produce sufficient blood cells, including red cells, white cells, and platelets. In SAA, stem cells are damaged, often due to the immune system attacking them.⁴

The failure to produce enough blood cells leaves patients 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, and in its most severe form, it can be fatal.⁴

Stem cell transplantation offers a potential cure for SAA. However, many patients lack a matched sibling donor, severely limiting their curative options.¹

The Breakthrough Data: Rapid Recovery and High Survival

Omidubicel-onlv provides a new avenue for those high-risk patients. The FDA approval is based on highly encouraging results from an ongoing open-label, single-center study (NCT03173937) led by Richard Childs, MD, of the National Heart, Lung, and Blood Institute at the national Institutes of Health.²

The study is focused on patients whose disease has not responded to standard therapies, who are considered high risk but have demonstrated “significantly better than expected outcomes,” according to Childs.¹ The data highlight omidubicel-onlv’s ability to promote rapid and robust recovery of blood counts.²

According to new data presented at the 2025 American Society of Hematology Annual Meeting, 95% of patients achieved rapid neutrophil recovery, with a median time to recovery reported at 8 days.² Initial approval data indicated a median time of 11 days, with 86% achieving early and sustained neutrophil recovery at 100 days.¹ The data also showed a 94% disease-free and overall survival rate, with 86% of patients achieving red blood cell transfusion independence.²

Crucially, the therapy demonstrated a remarkably low incidence of severe adverse events associated with stem cell transplantation. Just 16% of patients experienced mild acute (Blood & Marrow Transplant Clinical Trials Network grade 2) graft-versus-host disease (GVHD) and no cases of severe acute GVHD (grade 3-4) or chronic GVHD were observed.²

Implications for Patient Management and Health Care Teams

The FDA approval of omidubicel-onlv for SAA represents a potentially transformative shift for patients, offering a novel transplant option to many who lack a matched related donor.¹ Managing SAA is inherently complex, involving balancing the risks associated with bone marrow failure (susceptibility to frequent or prolonged infections, prolonged bleeding from cuts or injuries, etc.) with the necessary treatments.⁴

Health care providers must also consider that certain factors, including radiation/chemotherapy treatments, exposure to toxic chemicals, and use of specific prescription medications (such as chloramphenicol or gold compounds for rheumatoid arthritis) can cause or increase the risk of aplastic anemia.⁴

Successful deployment of omidubicel-onlv, a complex cell therapy, requires highly coordinated clinical and logistical support. For pharmacists, managing drug interactions, coordinating the cold chain logistics of cell product handling, and ensuring proper pre- and post-transplant supportive medication protocols are integral to the patient’s care journey.

REFERENCES

1. FDA approves Omisirge as first approved cell therapy to treat severe aplastic anemia. News release. BioSpace. December 8, 2025. Accessed December 8, 2025. https://www.biospace.com/press-releases/fda-approves-omisirger-as-first-approved-cell-therapy-to-treat-severe-aplastic-anemia

2. Additional positive results for Omisirge in treating severe aplastic anemia presented at ASH. News release. BioSpace. December 8, 2025. Accessed December 8, 2025. https://www.biospace.com/press-releases/additional-positive-results-for-omisirger-in-treating-severe-aplastic-anemia-presented-at-ash

3. Gallagher A. FDA approves Gamida Cell’s Omisirge for planned umbilical cord blood transplantation. Pharmacy Times. April 19, 2023. Accessed December 8, 2025. https://www.pharmacytimes.com/view/fda-approves-gamida-cell-s-omisirge-for-planned-umbilical-cord-blood-transplantation

4. Aplastic anemia. Mayo Clinic. May 3, 2025. Accessed December 8, 2025. https://www.mayoclinic.org/diseases-conditions/aplastic-anemia/symptoms-causes/syc-20355015