UM171 Expanded Cord Blood In Patients With High-Risk Acute Leukemia/Myelodysplasia

Allogeneic hematopoietic stem cell transplantation is a life-saving procedure in patients with blood cancers. Cord blood (CB) represents an alternative source of stem cells, which is associated with a lower risk of relapse, especially in the presence of minimal residual disease in the setting of acute leukemia and myelodysplasia. Furthermore, CB has the added advantage of being associated with a low risk of chronic graft versus host disease (GVHD). Unfortunately, CB transplants are hampered by a higher risk of transplant related mortality (TRM) when compared to bone marrow/peripheral blood transplants because of the limited cell dose of CB. In the previous UM171 trial (NCT02668315), the CB expansion protocol using the ECT-001-CB technology (UM171 molecule) has proven to be technically feasible and safe. UM171 expanded CB was associated with a median neutrophil recovery at day (D)+18 post transplant. Amongst 22 patients who received a single UM171 CB transplant with a median follow-up of 18 months, risk of TRM (5%) and grade 3-4 acute GVHD (10%) were low. There was no moderate-severe chronic GVHD. Thus, overall and progression free survival at 12 months were impressive at 90% and 74%, respectively. The UM171 expansion protocol allowed access to smaller, better HLA matched CBs as \>80% of patients received a 6-7/8 HLA matched CB. Interestingly there were 5 patients who had already failed an allogeneic transplant and 5 patients with refractory/relapsed acute leukemia/aggressive lymphoma. Despite this high risk population, progression was 20% at 12 months. Hence, in this new trial, investigators are targeting patients with high and very high-risk acute leukemia/myelodysplasia to test the antileukemia effect of this new graft, a UM171 expanded CB.