Lymphoid and myeloid immune cell reconstitution after nicotinamide-expanded cord blood transplantation.

Omidubicel (nicotinamide-expanded cord blood) is a potential alternative source for allogeneic hematopoietic cell transplantation (HCT) when an HLA-identical donor is lacking. A phase I/II trial with standalone omidubicel HCT showed rapid and robust neutrophil and platelet engraftment. In this study, we evaluated the immune reconstitution (IR) of patients receiving omidubicel grafts during the first 6 months post-transplant, as IR is critical for favorable outcomes of the procedure. Data was collected from the omidubicel phase I-II international, multicenter trial. The primary endpoint was the probability of achieving adequate CD4+ T-cell IR (CD4IR: > 50 × 106/L within 100 days). Secondary endpoints were the recovery of T-cells, natural killer (NK)-cells, B-cells, dendritic cells (DC), and monocytes as determined with multicolor flow cytometry. LOESS-regression curves and cumulative incidence plots were used for data description. Thirty-six omidubicel recipients (median 44; 13-63 years) were included, and IR data was available from 28 recipients. Of these patients, 90% achieved adequate CD4IR. Overall, IR was complete and consisted of T-cell, monocyte, DC, and notably fast NK- and B-cell reconstitution, compared to conventional grafts. Our data show that transplantation of adolescent and adult patients with omidubicel results in full and broad IR, which is comparable with IR after HCT with conventional graft sources.

Omidubicel vs standard myeloablative umbilical cord blood transplantation: results of a phase 3 randomized study.

Omidubicel is an ex vivo expanded hematopoietic progenitor cell and nonexpanded myeloid and lymphoid cell product derived from a single umbilical cord blood unit. We report results of a phase 3 trial to evaluate the efficacy of omidubicel compared with standard umbilical cord blood transplantation (UCBT). Between January 2017 and January 2020, 125 patients age 13 to 65 years with hematologic malignancies were randomly assigned to omidubicel vs standard UCBT. Patients received myeloablative conditioning and prophylaxis with a calcineurin inhibitor and mycophenolate mofetil for graft-versus-host disease (GVHD). The primary end point was time to neutrophil engraftment. The treatment arms were well balanced and racially diverse. Median time to neutrophil engraftment was 12 days (95% confidence interval [CI], 10-14 days) for the omidubicel arm and 22 days (95% CI, 19-25 days) for the control arm (P < .001). The cumulative incidence of neutrophil engraftment was 96% for patients receiving omidubicel and 89% for patients receiving control transplants. The omidubicel arm had faster platelet recovery (55% vs 35% recovery by 42 days; P = .028), had a lower incidence of first grade 2 to 3 bacterial or invasive fungal infection (37% vs 57%; P = .027), and spent more time out of hospital during the first 100 days after transplant (median, 61 vs 48 days; P = .005) than controls. Differences in GVHD and survival between the 2 arms were not statistically significant. Transplantation with omidubicel results in faster hematopoietic recovery and reduces early transplant-related complications compared with standard UCBT. The results suggest that omidubicel may be considered as a new standard of care for adult patients eligible for UCBT. The trial was registered at www.clinicaltrials.gov as #NCT02730299.

Cohort-Controlled Comparison of Umbilical Cord Blood Transplantation Using Carlecortemcel-L, a Single Progenitor-Enriched Cord Blood, to Double Cord Blood Unit Transplantation.

Umbilical cord blood (UCB) transplantation has a high early mortality rate primarily related to transplanted stem cell dose. To decrease early mortality and enhance engraftment, a portion of selected cord blood units (20% to 50%) was expanded with cytokines and the copper chelator tetraethylenepentamine (carlecortemcel-L) and transplanted with the unmanipulated fraction after myeloablative conditioning. The primary endpoint was 100-day survival, which was compared with a contemporaneous double-unit cord blood transplantation (DUCBT) group. We enrolled 101 patients at 25 sites; the DUCBT comparison (n = 295) was selected from international registries using study eligibility criteria. Baseline carlecortemcel-L study group unit nucleated cell (NC) and CD34+ were 3.06 × 107 cell dose/kg and 1.64 × 105 cell dose/kg. Median NC and CD34+ fold expansion were 400 and 77, with a mean total CD34 infused of 9.7 × 105/kg. The 100-day survival was 84.2% for the carlecortemcel-L study group versus 74.6% for the DUCBT group (odds ratio, .50; 95% CI, .26 to .95; P = .035). Survival at day 180 was similar for the 2 groups; the major cause of death after day 100 was opportunistic infections. Faster median neutrophil (21 days versus 28 days; P < .0001), and platelet (54 days versus 105 days; P = .008) engraftment was seen in the carlecortemcel-L study group; acute and chronic graft-versus-host disease rates were similar. In this multinational comparative study, transplanting expanded CD34+ stem cells from a portion of a single UCB unit, with the remaining unmanipulated fraction improved 100-day survival compared with DUCBT control patients while facilitating myeloid and platelet engraftment. This trial was registered at www.clinicaltrials.gov as #NCT00469729.

Umbilical cord blood expansion with nicotinamide provides long-term multilineage engraftment.

BACKGROUND: Delayed hematopoietic recovery is a major drawback of umbilical cord blood (UCB) transplantation. Transplantation of ex vivo-expanded UCB shortens time to hematopoietic recovery, but long-term, robust engraftment by the expanded unit has yet to be demonstrated. We tested the hypothesis that a UCB-derived cell product consisting of stem cells expanded for 21 days in the presence of nicotinamide and a noncultured T cell fraction (NiCord) can accelerate hematopoietic recovery and provide long-term engraftment. METHODS: In a phase I trial, 11 adults with hematologic malignancies received myeloablative bone marrow conditioning followed by transplantation with NiCord and a second unmanipulated UCB unit. Safety, hematopoietic recovery, and donor engraftment were assessed and compared with historical controls. RESULTS: No adverse events were attributable to the infusion of NiCord. Complete or partial neutrophil and T cell engraftment derived from NiCord was observed in 8 patients, and NiCord engraftment remained stable in all patients, with a median follow-up of 21 months. Two patients achieved long-term engraftment with the unmanipulated unit. Patients transplanted with NiCord achieved earlier median neutrophil recovery (13 vs. 25 days, P < 0.001) compared with that seen in historical controls. The 1-year overall and progression-free survival rates were 82% and 73%, respectively. CONCLUSION: UCB-derived hematopoietic stem and progenitor cells expanded in the presence of nicotinamide and transplanted with a T cell-containing fraction contain both short-term and long-term repopulating cells. The results justify further study of NiCord transplantation as a single UCB graft. If long-term safety is confirmed, NiCord has the potential to broaden accessibility and reduce the toxicity of UCB transplantation. TRIAL REGISTRATION: Clinicaltrials.gov NCT01221857. FUNDING: Gamida Cell Ltd.

Sequence-based design of kinase inhibitors applicable for therapeutics and target identification.

A platform for specifically modulating kinase-dependent signaling using peptides derived from the catalytic domain of the kinase is presented. This technology, termed KinAce, utilizes the canonical structure of protein kinases. The targeted regions (subdomain V and subdomains IX and X) are analyzed and their sequence, three-dimensional structure, and involvement in protein-protein interaction are highlighted. Short myristoylated peptides were derived from the target regions of the tyrosine kinases c-Kit and Lyn and the serine/threonine kinases 3-phosphoinositide-dependent kinase-1 (PDK1) and Akt/protein kinase B (PKB). For each kinase an active designer peptide is shown to selectively inhibit the signaling of the kinase from which it is derived, and to inhibit cancer cell proliferation in the micromolar range. This technology emerges as an applicable tool for deriving sequence-based selective inhibitors for a broad range of protein kinases as hits that may be further developed into drugs. Moreover, it enables identification of novel kinase targets for selected therapeutic indications as demonstrated in the KinScreen application.