Long-term benefits for patients with hematologic malignancies were seen with allogeneic hematopoietic stem cell transplantation (allo-HSCT) and omidubicel, in comparison with umbilical cord blood transplantation (UCBT). This is according to follow-up results of a phase 3 trial presented at the 2022 Tandem Meetings by Mitchell E Horwitz, MD, of Duke University Medical Center, and colleagues.

Omidubicel is a cell therapy associated with preserved stem cell function and optimized homing and self-renewal, according to the researchers. Earlier trial analyses of primary and secondary end points suggested the combination of allo-HSCT and omidubicel was superior to standard UCBT in this study population. In the current analysis, Dr Horwitz and colleagues presented follow-up results from 1 year after transplantation.

The randomized, multicenter study included patients with hematologic malignancies from 7 nations. The follow-up report emphasized end points of 1-year nonrelapse mortality (NRM), disease-free survival (DFS), overall survival (OS), relapse, and grade 3 viral infections that occurred by 15 months postrandomization. However, the study was not powered to determine statistical differences between treatment arms for these analyses.


Continue Reading

The median follow-up for the presented analysis was 14 months (range, 1-20). The study population consisted of 125 patients, many of whom had acute leukemia and moderate to high disease risk. The median patient age was 41 years.

The 1-year cumulative incidence of NRM for patients in this analysis was 15% for those in the arm receiving allo-HSCT with omidubicel (omidubicel arm), and it was 29% for patients in the UCBT arm (P =.068). Survival rates were 73% for the omidubicel arm and 60% for the UCBT arm (P =.13). The adjusted hazard ratio for mortality trended toward favoring the omidubicel arm, at 0.61 (95% CI, 0.32-1.15; P =.075).

DFS was similar between treatment arms. The DFS rate was 63% for the omidubicel arm, and it was 56% for the UCBT arm (P =.4). Cumulative incidence of relapse was also similar between arms, at 23% for the omidubicel arm, and at 16% for the UCBT arm (P =.32).

The 1-year incidence of grade 3 viral infection was 8% for the omidubicel arm, and it was 27% for the UCBT arm (P =.04). The 1-year incidence of grade 2 or 3 bacterial or invasive fungal infections was 45% for the omidubicel arm, and it was 70% for the UCBT arm.

The researchers concluded that use of omidubicel was linked to long-term benefits over UCBT in terms of 1-year NRM and relapse rates. They also indicated the OS rates show a trend of favoring the omidubicel arm over time, and they considered the option of using omidubicel to be supported by its clinical benefit.

Read more of Hematology Advisor’s coverage of the 2022 Tandem Meetings by visiting the conference page.

Reference

Horwitz ME, Stiff P, Cutler C, et al. Allogeneic hematopoietic stem cell (allo-HSCT) transplant with omidubicel demonstrates sustained clinical improvement versus standard myeloablative umbilical cord blood transplantation (UCBT): final results of a phase III randomized, multicenter study. Presented at: 2022 Tandem Meetings; April 23-26, 2022. Abstract 86.