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Impact of tumor microenvironment on efficacy of anti-CD19 CAR T cell therapy or chemotherapy and transplant in large B cell lymphoma
Locke, F. L., Filosto, S., Chou, J., Vardhanabhuti, S., Perbost, R., Dreger, P., Hill, B. T., Lee, C., Zinzani, P. L., Kröger, N., et al
Nature medicine. 2024
Abstract
The phase 3 ZUMA-7 trial in second-line large B cell lymphoma demonstrated superiority of anti-CD19 CAR T cell therapy (axicabtagene ciloleucel (axi-cel)) over standard of care (SOC; salvage chemotherapy followed by hematopoietic transplantation) ( NCT03391466 ). Here, we present a prespecified exploratory analysis examining the association between pretreatment tumor characteristics and the efficacy of axi-cel versus SOC. B cell gene expression signature (GES) and CD19 expression associated significantly with improved event-free survival for axi-cel (P = 0.0002 for B cell GES; P = 0.0165 for CD19 expression) but not SOC (P = 0.9374 for B cell GES; P = 0.5526 for CD19 expression). Axi-cel showed superior event-free survival over SOC irrespective of B cell GES and CD19 expression (P = 8.56 × 10(-9) for B cell GES high; P = 0.0019 for B cell GES low; P = 3.85 × 10(-9) for CD19 gene high; P = 0.0017 for CD19 gene low). Low CD19 expression in malignant cells correlated with a tumor GES consisting of immune-suppressive stromal and myeloid genes, highlighting the inter-relation between malignant cell features and immune contexture substantially impacting axi-cel outcomes. Tumor burden, lactate dehydrogenase and cell-of-origin impacted SOC more than axi-cel outcomes. T cell activation and B cell GES, which are associated with improved axi-cel outcome, decreased with increasing lines of therapy. These data highlight differences in resistance mechanisms to axi-cel and SOC and support earlier intervention with axi-cel.
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Donor Lymphocyte Infusion and Molecular Monitoring for Relapsed Myelofibrosis After Hematopoietic Cell Transplantation
Gagelmann, N., Wolschke, C., Badbaran, A., Janson, D., Berger, C., Klyuchnikov, E., Ayuk, F., Fehse, B., Kröger, N.
HemaSphere. 2023;7(7):e921
Abstract
Hematopoietic cell transplantation (HCT) is a curative approach for myelofibrosis patients, but relapse is a major cause of treatment failure. We investigated the effect of donor lymphocyte infusion (DLI) in 37 patients with molecular (n = 17) or hematological relapse (n = 20) after HCT. Patients received median of 2 (range, 1-5) cumulative DLI (total of 91 infusions). Median starting dose was 1 × 10(6) cells/kg, escalated by half-log ≥6 weeks if no response nor graft-versus-host disease (GvHD) occurred. Median time to first DLI was 40 weeks for molecular relapse versus 145 weeks for hematological relapse. Overall molecular complete response (mCR) at any time was 73% (n = 27) and was significantly higher for initial molecular relapse (88%) versus hematological relapse (60%; P = 0.05). The 6-year overall survival was 77% versus 32% (P = 0.03). Acute GvHD 2-4 occurred in 22% and half of the patients achieved mCR without any GvHD. All patients who relapsed from mCR achieved after first DLI could be salvaged with subsequent DLI, showing long-term survival. No second HCT was needed for molecular relapse versus 6 for hematological relapse. This comprehensive and largest study to date suggests molecular monitoring together with DLI as standard of care and a crucial approach to achieve excellent outcomes in relapsed myelofibrosis.
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Analysis benefits of a second Allo-HSCT after CAR-T cell therapy in patients with relapsed/refractory B-cell acute lymphoblastic leukemia who relapsed after transplant
Cao, X. Y., Zhang, J. P., Zhao, Y. L., Xiong, M., Zhou, J. R., Lu, Y., Sun, R. J., Wei, Z. J., Liu, D. Y., Zhang, X., et al
Frontiers in immunology. 2023;14:1191382
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Editor's Choice
Abstract
BACKGROUND Chimeric antigen receptor (CAR) T-cell therapy has demonstrated high initial complete remission (CR) rates in B-cell acute lymphoblastic leukemia (B-ALL) patients, including those who relapsed after transplant. However, the duration of remission requires improvements. Whether bridging to a second allogeneic hematopoietic stem cell transplant (allo-HSCT) after CAR-T therapy can improve long-term survival remains controversial. We retrospectively analyzed long-term follow-up data of B-ALL patients who relapsed post-transplant and received CAR-T therapy followed by consolidation second allo-HSCT to investigate whether such a treatment sequence could improve long-term survival. METHODS A single-center, retrospective study was performed between October 2017 and March 2022, involving 95 patients who received a consolidation second transplant after achieving CR from CAR-T therapy. RESULTS The median age of patients was 22.8 years (range: 3.3-52.8) at the second transplant. After the first transplant, 71 patients (74.7%) experienced bone marrow relapse, 16 patients (16.8%) had extramedullary relapse, 5 patients (5.3%) had both bone marrow and extramedullary relapse and 3/95 patients (3.2%) had positive minimal residual disease (MRD) only. Patients received autologous (n=57, 60.0%) or allogeneic (n=28, 29.5%) CAR-T cells, while 10 patients (10.5%) were unknown. All patients achieved CR after CAR-T therapy. Before second HSCT, 86 patients (90.5%) were MRD-negative, and 9 (9.5%) were MRD-positive. All second transplant donors were different from the first transplant donors. The median follow-up time was 623 days (range: 33-1901) after the second HSCT. The 3-year overall survival (OS) and leukemia-free survival (LFS) were 55.3% (95%CI, 44.3-66.1%) and 49.8% (95%CI, 38.7-60.9%), respectively. The 3-year relapse incidence (RI) and non-relapse mortality (NRM) were 10.5% (95%CI, 5.6-19.6%) and 43.6% (95%CI, 33.9-56.2%), respectively. In multivariate analysis, the interval from CAR-T to second HSCT ≤90 days was associated with superior LFS(HR, 4.10, 95%CI,1.64-10.24; p=0.003) and OS(HR, 2.67, 95%CI, 1.24-5.74, p=0.012), as well as reduced NRM (HR, 2.45, 95%CI, 1.14-5.24, p=0.021). CONCLUSIONS Our study indicated that CAR-T therapy followed by consolidation second transplant could significantly improve long-term survival in B-ALL patients who relapsed post-transplant. The second transplant should be considered in suitable patients and is recommended to be performed within 90 days after CAR-T treatment.
PICO Summary
Population
Adults with acute lymphoblastic leukaemia who were minimal residual disease-positive after first transplant at a single centre in China (n=95)
Intervention
CAR-T therapy followed by consolidation allogeneic transplant, using a different donor
Comparison
None
Outcome
The median follow-up time was 623 days (range: 33-1901) after the second HSCT. The 3-year overall survival (OS) and leukemia-free survival (LFS) were 55.3% (95%CI, 44.3-66.1%) and 49.8% (95%CI, 38.7-60.9%), respectively. The 3-year relapse incidence (RI) and non-relapse mortality (NRM) were 10.5% (95%CI, 5.6-19.6%) and 43.6% (95%CI, 33.9-56.2%), respectively. In multivariate analysis, the interval from CAR-T to second HSCT ≤90 days was associated with superior LFS(HR, 4.10, 95%CI,1.64-10.24) and OS(HR, 2.67, 95%CI, 1.24-5.74), as well as reduced NRM (HR, 2.45, 95%CI, 1.14-5.24).
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Prevention of CMV/EBV reactivation by double-specific T cells in patients after allogeneic stem cell transplantation: results from the randomized phase I/IIa MULTIVIR-01 study
Gerbitz, A., Gary, R., Aigner, M., Moosmann, A., Kremer, A., Schmid, C., Hirschbuehl, K., Wagner, E., Hauptrock, B., Teschner, D., et al
Frontiers in immunology. 2023;14:1251593
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Editor's Choice
Abstract
INTRODUCTION Allogeneic stem cell transplantation is used to cure hematologic malignancies or deficiencies of the hematopoietic system. It is associated with severe immunodeficiency of the host early after transplant and therefore early reactivation of latent herpesviruses such as CMV and EBV within the first 100 days are frequent. Small studies and case series indicated that application of herpes virus specific T cells can control and prevent disease in this patient population. METHODS We report the results of a randomized controlled multi centre phase I/IIa study (MULTIVIR-01) using a newly developed T cell product with specificity for CMV and EBV derived from the allogeneic stem cell grafts used for transplantation. The study aimed at prevention and preemptive treatment of both viruses in patients after allogeneic stem cell transplantation targeting first infusion on day +30. Primary endpoints were acute transfusion reaction and acute-graft versus-host-disease after infusion of activated T cells. RESULTS Thirty-three patients were screened and 9 patients were treated with a total of 25 doses of the T cell product. We show that central manufacturing can be achieved successfully under study conditions and the product can be applied without major side effects. Overall survival, transplant related mortality, cumulative incidence of graft versus host disease and number of severe adverse events were not different between treatment and control groups. Expansion of CMV/EBV specific T cells was observed in a fraction of patients, but overall there was no difference in virus reactivation. DISCUSSION Our study results indicate peptide stimulated epitope specific T cells derived from stem cell grafts can be administered safely for prevention and preemptive treatment of reactivation without evidence for induction of acute graft versus host disease. CLINICAL TRIAL REGISTRATION https://clinicaltrials.gov, identifier NCT02227641.
PICO Summary
Population
Adults undergoing allogeneic transplant from a matched donor who was seropositive for cytomegalovirus (CMV) and Epstein-barr virus (EBV) and enrolled in the MULTIVIR-01 study in centres in Germany (n=33)
Intervention
A newly developed T cell product with specificity for CMV and EBV derived from the allogeneic stem cell grafts used for transplantation. (n=16; 9 received full treatment)
Comparison
Control (n=13)
Outcome
Central manufacturing can be achieved successfully under study conditions and the product can be applied without major side effects. Overall survival, transplant related mortality, cumulative incidence of graft versus host disease and number of severe adverse events were not different between treatment and control groups. Expansion of CMV/EBV specific T cells was observed in a fraction of patients, but overall there was no difference in virus reactivation
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Comparison of Outcomes of Donor Lymphocyte Infusions With or Without Lenalidomide in Patients with Hematological Malignancies Post Allogeneic HSCT
Punatar, S., Murugaiyan, V., Kumbhalwar, K., Gokarn, A., Chichra, A., Mirgh, S., Nayak, L., Bonda, A., Jindal, N., Shirure, V., et al
Indian journal of hematology & blood transfusion : an official journal of Indian Society of Hematology and Blood Transfusion. 2023;39(1):40-49
Abstract
Outcomes with DLI alone for post-transplant relapsed hematological malignancies are poor especially in acute leukemias. Addition of immunomodulatory drugs to DLI may augment GVL effect. Use of lenalidomide with DLI to augment GVL has not been previously reported. This retrospective analysis was to compare the outcomes of DLI with or without lenalidomide. All consecutive patients who received DLI from 01/2010 through 01/2020 were included. DLIs were given without any immunosuppression. Lenalidomide, when used, was given continuously, starting with 1st or subsequent DLI. Patients who received lenalidomide were compared with those who did not. Event (hematological relapse or death) free survival (EFS) and overall survival (OS) were calculated from 1st DLI. Primary objective was to compare OS. Secondary objectives were EFS, CR rates, acute GVHD, lenalidomide toxicities and DLI related mortality (TRM). Total 61 patients received DLI-43 without and 18 with lenalidomide; all outcomes in the 2 groups were similar. There were 26 patients with HLA-A*24 and/or HLA-B*40. Among these, trend towards improvement in OS (median OS not reached vs. 8 months, 4 year OS was 62% vs. 32%, p = 0.1) and EFS (median 9 vs. 1 month, 4 year EFS 50% vs. 22%, p = 0.1) was seen with lenalidomide. Overall, there was no improvement in outcomes by adding lenalidomide to DLI. However, among patients with HLA*24 or B*40, there was a trend to improved survival with lenalidomide. Use of lenalidomide to augment the GVL effect of DLI warrants further exploration.
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A phase II study of chidamide, cytarabine, aclarubicin, granulocyte colony-stimulating factor, and donor lymphocyte infusion for relapsed acute myeloid leukemia and myelodysplastic syndrome after allogeneic hematopoietic stem cell transplantation
Wei, Y., Wang, L., Zhu, C., Li, H., Bo, J., Zhang, R., Lu, N., Wu, Y., Gao, X., Dou, L., et al
Medical oncology (Northwood, London, England). 2023;40(2):77
Abstract
Chemotherapy followed by donor lymphocyte infusion (DLI) is a promising treatment for relapsed acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS) after allogeneic hematopoietic stem cell transplantation (allo-HSCT). However, the best strategy for administering this therapy is still unclear. This study sought to explore the efficacy and safety of chidamide and CAG (cytarabine, aclarubicin, and granulocyte colony-stimulating factor) (CCAG) regimen followed by DLI in relapsed AML/MDS after allo-HSCT. This was a single-arm, phase II trial in patients with relapsed AML/MDS after allo-HSCT. CCAG regimen followed by DLI was given according to the inclusion and exclusion criteria. Twenty adult patients were enrolled. The median follow-up time was 12 months. The complete remission (CR) rate was 45% and the partial remission (PR) rate was 5%. The 1-year overall survival (OS) was 56.7% (95% confidence interval (95% CI), 31.6-75.6%), and the median OS was 19 months. The 1-year relapse-free survival (RFS) was 83.3% (95% CI, 27.3-97.5%). Patients relapsing more than 6 months after HSCT and achieving CR/PR after CCAG plus DLI regimen attained significantly higher survival rates. The cumulative incidence of grade III-IV acute graft-versus-host disease (aGVHD) was 9.4%. There was no treatment-related mortality (TRM). These data suggest that CCAG plus DLI regimen is safe and induces durable remission and superior survival in patients with relapsed AML/MDS after allo-HSCT. Trial registration number: ChiCTR.org identifier: ChiCTR1800017740 and date of registration: August 12, 2018.
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Safety and Efficacy of Axicabtagene Ciloleucel versus Standard of Care in Patients 65 Years of Age or Older with Relapsed/Refractory Large B-Cell Lymphoma
Westin, J. R., Locke, F. L., Dickinson, M., Ghobadi, A., Elsawy, M., van Meerten, T., Miklos, D. B., Ulrickson, M. L., Perales, M. A., Farooq, U., et al
Clinical cancer research : an official journal of the American Association for Cancer Research. 2023;:Of1-of12
Abstract
PURPOSE Older patients with relapsed/refractory (R/R) large B-cell lymphoma (LBCL) may be considered ineligible for curative-intent therapy including high-dose chemotherapy with autologous stem-cell transplantation (HDT-ASCT). Here, we report outcomes of a preplanned subgroup analysis of patients ≥65 years in ZUMA-7. PATIENTS AND METHODS Patients with LBCL refractory to or relapsed ≤12 months after first-line chemoimmunotherapy were randomized 1:1 to axicabtagene ciloleucel [axi-cel; autologous anti-CD19 chimeric antigen receptor (CAR) T-cell therapy] or standard of care (SOC; 2-3 cycles of chemoimmunotherapy followed by HDT-ASCT). The primary endpoint was event-free survival (EFS). Secondary endpoints included safety and patient-reported outcomes (PROs). RESULTS Fifty-one and 58 patients aged ≥65 years were randomized to axi-cel and SOC, respectively. Median EFS was greater with axi-cel versus SOC (21.5 vs. 2.5 months; median follow-up: 24.3 months; HR, 0.276; descriptive P < 0.0001). Objective response rate was higher with axi-cel versus SOC (88% vs. 52%; OR, 8.81; descriptive P < 0.0001; complete response rate: 75% vs. 33%). Grade ≥3 adverse events occurred in 94% of axi-cel and 82% of SOC patients. No grade 5 cytokine release syndrome or neurologic events occurred. In the quality-of-life analysis, the mean change in PRO scores from baseline at days 100 and 150 favored axi-cel for EORTC QLQ-C30 Global Health, Physical Functioning, and EQ-5D-5L visual analog scale (descriptive P < 0.05). CAR T-cell expansion and baseline serum inflammatory profile were comparable in patients ≥65 and <65 years. CONCLUSIONS Axi-cel is an effective second-line curative-intent therapy with a manageable safety profile and improved PROs for patients ≥65 years with R/R LBCL.
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Efficacy and safety of chimeric antigen receptor T-cell (CAR-T) therapy in hematologic malignancies: a living systematic review on comparative studies
Saiz, L. C., Leache, L., Gutiérrez-Valencia, M., Erviti, J., Rojas Reyes, M. X.
Therapeutic advances in hematology. 2023;14:20406207231168211
Abstract
BACKGROUND Chimeric antigen receptor T-cell (CAR-T) cell therapies have been claimed to be curative in responsive patients. Nonetheless, response rates can vary according to different characteristics, and these therapies are associated with important adverse events such as cytokine release syndrome, neurologic adverse events, and B-cell aplasia. OBJECTIVES This living systematic review aims to provide a timely, rigorous, and continuously updated synthesis of the evidence available on the role of CAR-T therapy for the treatment of patients with hematologic malignancies. DESIGN A systematic review with meta-analysis of randomized controlled trials (RCTs) and comparative non-randomized studies of interventions (NRSI), evaluating the effect of CAR-T therapy versus other active treatments, hematopoietic stem cell transplantation, standard of care (SoC) or any other intervention, was performed in patients with hematologic malignancies. The primary outcome is overall survival (OS). Certainty of the evidence was determined using the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) approach. DATA SOURCES AND METHODS Searches were performed in the Epistemonikos database, which collates information from multiple sources to identify systematic reviews and their included primary studies, including Cochrane Database of Systematic Reviews, MEDLINE, EMBASE, CINAHL, PsycINFO, LILACS, DARE, HTA Database, Campbell database, JBI Database of Systematic Reviews and Implementation Reports, EPPI-Centre Evidence Library. A manual search was also carried out. We included the evidence published up to 1 July 2022. RESULTS We included the evidence published up to 1 July 2022. We considered 139 RCTs and 1725 NRSI as potentially eligible. Two RCTs (N = 681) comparing CAR-T therapy with SoC in patients with recurrent/relapsed (R/R) B-cell lymphoma were included. RCTs did not show statistical differences in OS, serious adverse events, or total adverse events with grade ⩾ 3. Higher complete response with substantial heterogeneity [risk ratio = 1.59; 95% confidence interval (CI) = (1.30-1.93); I (2) = 89%; 2 studies; 681 participants; very low certainty evidence] and higher progression-free survival [hazard ratio for progression or death = 0.49; 95% CI = (0.37-0.65); 1 study; 359 participants; moderate certainty evidence] were reported with CAR-T therapies. Nine NRSI (N = 540) in patients with T or B-cell acute lymphoblastic leukemia or R/R B-cell lymphoma were also included, providing secondary data. In general, the GRADE certainty of the evidence for main outcomes was mostly low or very low. CONCLUSION So far, assuming important limitations in the level of certainty due to scarce and heterogenous comparative studies, CAR-T therapies have shown some benefit in terms of progression-free survival, but no overall survival, in patients with R/R B-cell lymphoma. Despite one-arm trials have already facilitated approval of CAR-T cell treatments, additional evidence from large comparative studies is still needed to better characterize the benefit-harm ratio of the use of CAR-T in a variety of patient populations with hematological malignancies. REGISTRATION https://doi.org/10.12688/openreseurope.14390.1. PROSPERO/OSF PREREGISTRATION 10.17605/OSF.IO/V6HDX.
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A pro-inflammatory environment in bone marrow of Treg transplanted patients matches with graft-versus-leukemia effect
Guardalupi, F., Sorrentino, C., Corradi, G., Giancola, R., Baldoni, S., Ulbar, F., Fabi, B., Andres Ejarque, R., Timms, J., Restuccia, F., et al
Leukemia. 2023
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10.
Immune Reconstitution Profiling Suggests Antiviral Protection After Transplantation with Omidubicel: a Phase 3 Substudy
Szabolcs, P., Mazor, R. D., Yackoubov, D., Levy, S., Stiff, P., Rezvani, A., Hanna, R., Wagner, J., Keating, A., Lindemans, C. A., et al
Transplantation and cellular therapy. 2023
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Editor's Choice
Abstract
BACKGROUND Allogeneic hematopoietic cell transplantation (HCT) is a potentially curative treatment for hematological malignancies and non-malignant disorders. Rapid immune reconstitution (IR) following allogeneic HCT has been shown to be associated with improved clinical outcomes and lower infection rates. A global phase 3 trial (NCT02730299) of omidubicel, an advanced cell therapy manufactured from an appropriately human leukocyte antigen-matched single umbilical cord blood (UCB) unit, showed faster hematopoietic recovery, reduced rates of infection, and shorter hospitalizations in patients randomized to omidubicel compared with those randomized to standard UCB. OBJECTIVE This optional, prospective substudy of the phase 3 trial characterized the IR kinetics following HCT with omidubicel compared with UCB in a systematic and detailed manner. STUDY DESIGN In this substudy, 37 patients from 14 global sites were included (omidubicel: n=17, UCB: n=20). Peripheral blood samples were collected over 10 predefined time points from 7 to 365 days post-HCT. Flow cytometry immunophenotyping, T cell receptor excision circle quantification, and T cell receptor sequencing were employed to evaluate the longitudinal IR kinetics post-transplant and their association with clinical outcomes. RESULTS Patient characteristics in the two comparator cohorts were overall statistically similar, except for age and total body irradiation (TBI) based conditioning regimens. The median age (range) for patients who received omidubicel or UCB was 30 (13-62) years and 43 (19-55) years, respectively. The percentages of patients receiving TBI based conditioning regimens were 47% and 70% for omidubicel and UCB recipients, respectively. Graft characteristics differed in their cellular composition. Omidubicel recipients received a 33-fold higher median dose of CD34+ stem cells, while receiving one third of the median CD3+ lymphocyte dose infused to UCB transplanted patients. Compared with UCB, omidubicel recipients exhibited faster IR of all measured lymphoid and myelomonocytic subpopulations, predominantly in the first 14 days post-transplant. This effect involved circulating natural killer (NK) cells, helper T cells, monocytes, and dendritic cells, with superior long-term B cell recovery from Day 28. One-week post-HCT, omidubicel recipients exhibited 4.1 and 7.7 -fold increases in the median helper T and NK cell counts respectively, compared to their UCB transplanted counterparts. By three weeks post-HCT, omidubicel transplanted patients were 3-fold more likely to achieve clinically relevant helper T and NK cell counts of 100 cells/ µL or above. Similar to UCB, omidubicel yielded a balanced cellular subpopulation composition and diverse T cell receptor repertoire in the short to long term. Omidubicel's CD34+ cell content correlated with faster IR by Day 7 post-HCT, which in turn coincided with earlier hematopoietic recovery. Lastly, early NK and helper T cell reconstitution correlated with a decreased rate of post-HCT viral infections, suggesting a plausible explanation for this phenomenon among omidubicel recipients in the phase 3 study. CONCLUSIONS Our findings suggest that omidubicel efficiently promotes IR across multiple immune cells, including CD4+ T cells, B cells, NK cells, and dendritic cell subtypes as early as 7 days post-transplant, potentially endowing recipients of omidubicel with early protective immunity.
PICO Summary
Population
Adults with haematological malignancies enrolled in a randomised controlled trial (n=125) and selected for a substudy evaluating immune reconstitution kinetics (n=37)
Intervention
Omidubicel, an advanced cell therapy manufactured from an appropriately human leukocyte antigen-matched single umbilical cord blood unit (omidubicel, n=17)
Comparison
Standard cord blood transplantation (UCB, n=20)
Outcome
Compared with UCB, omidubicel recipients exhibited faster immune reconstitution (IR) of all measured lymphoid and myelomonocytic subpopulations, predominantly in the first 14 days post-transplant. This effect involved circulating natural killer (NK) cells, helper T cells, monocytes, and dendritic cells, with superior long-term B cell recovery from Day 28. One-week post-HCT, omidubicel recipients exhibited 4.1 and 7.7 -fold increases in the median helper T and NK cell counts respectively, compared to their UCB transplanted counterparts. By three weeks post-HCT, omidubicel transplanted patients were 3-fold more likely to achieve clinically relevant helper T and NK cell counts of 100 cells/ µL or above. Similar to UCB, omidubicel yielded a balanced cellular subpopulation composition and diverse T cell receptor repertoire in the short to long term. Omidubicel's CD34+ cell content correlated with faster IR by Day 7 post-HCT, which in turn coincided with earlier hematopoietic recovery. Lastly, early NK and helper T cell reconstitution correlated with a decreased rate of post-HCT viral infections, suggesting a plausible explanation for this phenomenon among omidubicel recipients in the phase 3 study.