A new study has pooled the results of 5 multicenter clinical trials of omidubicel transplantation in patients with sickle cell hemoglobinopathy or other hematologic malignancies. The results, published in Transplantation and Cellular Therapy, found that omidubicel was associated with durable engraftment, trilineage hematopoiesis, and immune competence over a 10-year follow-up.

“Given the theoretical concerns surrounding durability of expanded stem cell grafts, we set out to perform a long-term follow-up study to confirm the safety, immune function, and graft durability of omidubicel transplantation,” the authors wrote.

Omidubicel is an umbilical cord blood (UCB)-derived product that is expanded using nicotinamide, and it represents the first ex vivo expanded cell graft for standalone transplantation. In 2022, the US Food and Drug Administration (FDA) granted priority review to omidubicel’s biologics license application.

In previous studies on omidubicel, early benefits were demonstrated, but there have been concerns about the durability of expanded stem cell products.

Read more about sickle cell disease therapies

Here, the research team pooled long-term outcomes from 5 trials evaluating omidubicel transplantation between January 2011 and April 2021 in 105 patients. Two of the trials enrolled patients with sickle cell hemoglobinopathy, and the other 3 assessed patients with other hematologic malignancies.

Long-term, durable trilineage hematopoiesis was observed over up to 10 years of follow-up. The 3-year overall survival was 62.7%, and disease-free survival was 56.4%. The durability of the engraftment suggests that repopulating activity was maintained without the need for a concurrent unmanipulated UCB graft.

The authors note that 39% of the patient cohort were nonwhite individuals, and the results of the pooled analysis led the authors to conclude that omidubicel may expand the potential donor pool for underrepresented ethnic patient groups. However, further studies comparing omidubicel outcomes with those of other stem cell products are still needed.

Reference

Lin C, Schwarzbach A, Sanz J, et al. Multicenter long-term follow-up of allogeneic hematopoietic cell transplantation with omidubicel: a pooled analysis of five prospective clinical trials. Transplant Cell Ther. Published online February 10, 2023. doi:10.1016/j.jtct.2023.01.031