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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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CD19 CAR T cells are an effective therapy for posttransplant relapse in patients with B-lineage ALL: real-world data from Germany
Bader, P., Rossig, C., Hutter, M., Ayuk, F. A., Baldus, C. D., Bücklein, V. L., Bonig, H., Cario, G., Einsele, H., Holtick, U., et al
Blood advances. 2023;7(11):2436-2448
Abstract
Patients with precursor B-cell acute lymphoblastic leukemia (pB-ALL) who have relapsed after allogeneic hematopoietic stem cell transplantation (allo-HSCT), have relapsed more than once, or are resistant upfront have a dismal prognosis. CD19-targeted chimeric antigen receptor (CAR) T cells have evolved as potent immune therapies. Tisagenlecleucel (Tisa-cel) is a commercially available autologous CD19-directed CAR T-cell product. We performed a retrospective study inviting all CAR T-cell centers in Germany to participate. Eighty-one patients with pB-ALL were included. Twenty-eight days after CAR T-cell infusion, 71 patients (87.7%) were in complete response, and 8 (9.9%) were in nonremission. At 2 years, the probabilities of event-free survival (pEFS), relapse-free survival (pRFS), and overall survival (pOS) were 45.3%, 51.7%, and 53.2%, respectively. pEFS was not different in patients without (n = 16, 55.0%) vs with prior allo-HSCT (n = 65, 43.4%). In patients treated after allo-HSCT, the time to relapse after allo-HSCT was a strong predictor of outcome. Patients relapsing within 6 months of allo-HSCT had a disappointing pEFS of 18.4% (pOS = 16.0%); the pEFS for those relapsing later was 55.5% (pOS = 74.8%). Our study provides real-world experience in pediatric, adolescent, and young adult patients with ALL treated with Tisa-cel, where most patients were treated after having relapsed after allo-HSCT. A total of 45.3% were rescued with a single dose of Tisa-cel. Our novel finding that patients with ALL after allo-HSCT had by far a better pEFS if relapse occurred beyond 6 months might be helpful in clinical decision-making and motivates studies to uncover the reasons.
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CAR-T cell therapy followed by allogenic hematopoietic stem cell transplantation yielded comparable outcome between Ph like ALL and other high-risk ALL
Dai, H. P., Kong, D. Q., Shen, H. J., Cui, W., Wang, Q., Li, Z., Yin, J., Kang, L. Q., Yu, L., Wu, D. P., et al
Biomarker research. 2023;11(1):19
Abstract
It was previously believed that patients with Ph-like ALL had poorer prognosis compared with other B-ALL subgroups due to resistance to conventional chemotherapy and lack of targeted drugs. CAR-T therapy has been successfully applied in the treatment of relapsed and refractory B-ALL. Currently, there are few data on whether CAR-T therapy can alter the outcome of Ph-like ALL. Here we included 17 Ph-like, 23 Ph+ and 51 other B-ALL patients, who received autologous CAR T-cell therapy and subsequently allogenic stem cell transplantation. Patients in the Ph-like group and B-ALL-others group were younger that those in the Ph+ group (P=0.001). Ph-like and Ph+ ALL patients showed higher white blood cell counts at diagnosis (P=0.025). The percentage of patients with active disease before receiving CAR T-cells infusion was 64.7%, 39.1% and 62.7% in the Ph-like, Ph+ and B-ALL-others groups. The response rates to CAR-T therapy were 94.1% (16/17), 95.6% (22/23) and 98.0% (50/51) in the Ph-like, Ph+ and B-ALL-others groups. Measurable residual disease negative CR was achieved in 64.7% (11/17), 60.9% (14/23) and 54.9% (28/51) in the Ph-like, Ph+ and B-ALL-others groups, respectively. The estimated rates of 3-year overall survival (65.9%±16.5%, 59.7%±10.5% and 61.6%±7.3%, P=0.758) and 3-year relapse-free survival (59.8%±14.8%, 63.1%±10.5% and 56.3%±7.1%, P=0.764) were comparable among the Ph-like, Ph+ and B-ALL-others groups. Estimated 3-year cumulative relapse rate was 7.8%±0.6%, 23.4%±0.9% and 29.0%±0.4% (P=0.241). Our findings suggest that CART followed by allo-HSCT results in a comparable prognosis in Ph-like ALL and other high-risk B-ALL.Trial registration ClinicalTrials. gov, NCT03275493, Registered on September 7, 2017, prospectively registered and NCT03614858, Registered on August 3, 2018, prospectively registered.
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Donor-derived CD19 CAR-T Cells versus Chemotherapy Plus Donor Lymphocyte Infusion for Treatment of Recurrent CD19-positive B-ALL After Allogeneic Hematopoietic Stem Cell Transplantation
Tan, X., Wang, X. Q., Zhang, C., Zhao, X. L., Yao, H., Chen, G., Ma, Y. Y., Wen, Q., Gao, L., Gao, L., et al
Current medical science. 2023
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Editor's Choice
Abstract
OBJECTIVE This study aimed to compare the efficacy of anti-CD19 chimeric antigen receptor T cells (CAR-T cells) versus chemotherapy plus donor lymphocyte infusion (chemo-DLI) for treating relapsed CD19-positive B-cell acute lymphoblastic leukemia (B-ALL) after allogeneic hematopoietic stem cell transplantation (allo-HSCT). METHODS Clinical data of 43 patients with B-ALL who relapsed after allo-HSCT were retrospectively analyzed. Twenty-two patients were treated with CAR-T cells (CAR-T group), and 21 with chemotherapy plus DLI (chemo-DLI group). The complete remission (CR) and minimal residual disease (MRD)-negative CR rates, leukemia-free survival (LFS) rate, overall survival (OS) rate, and incidence of acute graft-versus-host disease (aGVHD), cytokine release syndrome (CRS) and immune effector cell-associated neurotoxicity syndrome (ICANS) were compared between the two groups. RESULTS The CR and MRD-negative CR rates in the CAR-T group (77.3% and 61.5%) were significantly higher than those in the chemo-DLI group (38.1% and 23.8%) (P=0.008 and P=0.003). The 1- and 2-year LFS rates in the CAR-T group were superior to those in the chemo-DLI group: 54.5% and 50.0% vs. 9.5% and 4.8% (P=0.0001 and P=0.00004). The 1- and 2-year OS rates in the CAR-T versus chemo-DLI group were 59.1% and 54.5% vs. 19% and 9.5% (P=0.011 and P=0.003). Six patients (28.6%) with grade 2-4 aGVHD were identified in the chemo-DLI group. Two patients (9.1%) in the CAR-T group developed grade 1-2 aGVHD. Nineteen patients (86.4%) developed CRS in the CAR-T group, comprising grade 1-2 CRS in 13 patients (59.1%) and grade 3 CRS in 6 patients (27.3%). Two patients (9.1%) developed grade 1-2 ICANS. CONCLUSION Donor-derived anti-CD19 CAR-T-cell therapy may be better, safer, and more effective than chemo-DLI for B-ALL patients who relapse after allo-HSCT.
PICO Summary
Population
Adults and children with relapsed CD19-positive ALL after allo-HSCT, from centres in China (n=43)
Intervention
CAR-T cell therapy (n-22),
Comparison
Chemotherapy plus donor lymphocyte infusion (DLI) treatment (n=21).
Outcome
The complete remission (CR) and minimal residual disease (MRD)-negative CR rates in the CAR-T group (77.3% and 61.5%) were significantly higher than those in the chemo-DLI group (38.1% and 23.8%). The 1- and 2-year leukaemia free surivival (LFS) rates in the CAR-T group were superior to those in the chemo-DLI group: 54.5% and 50.0% vs. 9.5% and 4.8%. The 1- and 2-year overall survival (OS) rates in the CAR-T versus chemo-DLI group were 59.1% and 54.5% vs. 19% and 9.5%. Six patients (28.6%) with grade 2-4 aGVHD were identified in the chemo-DLI group. Two patients (9.1%) in the CAR-T group developed grade 1-2 aGVHD. Nineteen patients (86.4%) developed CRS in the CAR-T group, comprising grade 1-2 CRS in 13 patients (59.1%) and grade 3 CRS in 6 patients (27.3%). Two patients (9.1%) developed grade 1-2 ICANS.
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Donor Hematopoietic Stem Cell/Lymphocyte Maintenance Treatment After CAR T-Cell Therapy in Patients With B-Cell Acute Lymphoblastic Leukemia Relapse Following Stem Cell Transplant
Li, Q., Lyu, C., Liu, M., Wang, J., Mou, N., Jiang, E., Zhang, R., Deng, Q.
Cell transplantation. 2023;32:9636897231158155
Abstract
Maintaining the efficacy of anti-CD19 chimeric antigen receptor modified (CAR) T-cell therapy in patients with B-cell acute lymphoblastic leukemia (B-ALL) relapse after allogeneic hematopoietic stem cell transplant (allo-HSCT) is an urgent problem. In this study, we aimed to compare the efficacy of donor hematopoietic stem cell infusion (DSI) therapy and donor lymphocyte infusion (DLI) therapy as a maintenance therapy after R/R B-ALL patients achieved CR in anti-CD19-CAR T-cell therapy but relapsed after allo-HSCT. In total, 22 B-ALL patients who relapsed after allo-HSCT received anti-CD19-CAR T-cell therapy. Patients who responded to CAR T-cell therapy received DSI or DLI as maintenance therapy. We compared the clinical responses, acute graft versus host disease (aGVHD), expansion of CAR-T-cells, and adverse events between the two groups. In our study, 19 patients received DSI/DLI as maintenance therapy. After DSI/DLI therapy, progression-free survival and overall survival were higher in the DSI group than in the DLI group at 365 days. The grades I and II of aGVHD was observed in four patients (36.4%) in the DSI group. Only one patient developed grade II aGVHD in the DLI group. The peaks of CAR T-cells in the DSI group were higher than those in the DLI group. IL-6 and TNF-α levels increased again in nine of 11 patients after DSI but not in the DLI group. Our findings indicate that for B-ALL patients who relapse after allo-HSCT, DSI is a feasible maintenance therapy if CR is obtained with CAR-T-cell therapy.
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Outcomes of Second Anti-CD19 CAR T-Cell Therapy (CART2) in Acute B Lymphoblastic Leukemia and the Impact of Allo-HSCT on Efficacy
Xu, Q., Shi, Y., Xue, L., An, F., Xu, H., Liu, X., Zhu, X., Sun, Z., Zhai, Z., Wang, X.
Cell transplantation. 2023;32:9636897231204724
Abstract
For patients exhibiting a suboptimal response to the first chimeric antigen receptor (CAR) T-cell therapy (CART1) or relapse after remission, secondary CAR T-cell therapy (CART2) for the same target may be an option. We retrospectively analyzed patients with acute B-cell lymphoblastic leukemia (B-ALL) receiving CD19 CART1 at our center (n = 84) to report the clinical outcomes of CART2 and to identify the factors that may influence the outcomes. Twenty-six patients received CART2 for suboptimal response or relapse post-CART1. The incidence of cytokine release syndrome (CRS) after CART2 was 65.4% (17/26), with 11 cases classified as grade 1 (42.3%), four cases as grade 2 (15.4%), and two cases as grade 3 (7.7%). Neurotoxicity was observed in one patient (3.8%) after CART2 infusion. Fourteen patients (53.8%) achieved complete remission (CR) after CART2. CART2 exhibited an inferior response rate (CART2: 53.8%, 14/26; CART1: 81.0%, 64/79; P = 0.006) and a lower incidence of severe CRS (CART2: 7.7%, 2/26; CART1: 30.4%, 24/79; P = 0.020) compared with CART1, with a median progression-free survival (PFS) and a median overall survival (OS) of 6.2 months and 11.2 months, respectively. In particular, patients who progressed after consolidative allogeneic hematopoietic stem cell transplantation (allo-HSCT) following CART1 and then received CART2 demonstrated promising outcomes with a response rate of 80.0% (8/10), a median PFS of 7.9 months, and a median OS of 25.1 months. After adjusting for the confounding factors, the response rate (85.7%, 6/7) of CART2 administered to this cohort was better than those who did not bridge to allo-HSCT receiving CART2 (28.6%, 2/7) or non-CART2 treatments (13.3%, 2/15). The median OS after CART2, which was not reached, was significantly better than the median OS after CART2 (3.9 months, P = 0.014) and non-CART2 treatments (6.0 months, P = 0.012) administered in patients who did not undergo consolidative allo-HSCT post-CART1. Our results indicated that, although less effective than CART1, a subset of patients can still benefit from CART2 with mild adverse effects. For patients who relapsed after consolidative allo-HSCT post-CART1, treatment with CART2 is a viable option.
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Practice preferences for consolidative HSCT following tisagenlecleucel in children and young adults with B-ALL
McNerney, K. O., Moskop, A., Winestone, L. E., Baggott, C., Talano, J. A., Schiff, D., Rossoff, J., Modi, A., Verneris, M. R., Laetsch, T. W., et al
Transplantation and cellular therapy. 2023
Abstract
BACKGROUND Tisagenlecleucel achieves excellent complete remission rates in children and young adults with relapsed or refractory B-acute lymphoblastic leukemia (B-ALL), but approximately 50% maintain long-term remissions. Consolidative hematopoietic stem cell transplant (cHSCT) is a potential strategy to reduce relapse risk but carries substantial short- and long-term toxicities. Additionally, several strategies for management of B-cell recovery (BCR) and next-generation sequencing (NGS) positivity post-tisagenlecleucel exist without an accepted standard. We hypothesized that practice preferences surrounding cHSCT as well as management of BCR and NGS positivity varies across tisagenlecleucel-prescribing physicians and sought to characterize current practice preferences. METHODS A survey focused on preferences regarding the use of cHSCT, management of BCR, and NGS positivity was distributed to physicians that prescribe tisagenlecleucel for children and young adults with B-ALL. Responses were collected from August 2022 to April 2023. RESULTS Fifty-nine unique responses were collected across 43 institutions. All respondents prescribed tisagenlecleucel for children and young adults. The clinical focus of respondents was HSCT in 71% followed by leukemia/lymphoma in 24%. In HSCT-naïve patients receiving tisagenlecleucel, 57% of respondents indicated they made individualized decision for cHSCT based on patient factors, while 22% indicated they would avoid and 21% indicated they would pursue cHSCT where feasible. Select factors influenced >50% of respondents towards recommending cHSCT (either increased likelihood or would always recommend) including pre-infusion disease burden >25%, primary refractory B-ALL, M3 bone marrow following re-induction for relapse, KMT2A-rearranged B-ALL, history of blinatumomab non-response, and HSCT naïve status. Most respondents indicated they would pursue HSCT for HSCT-naïve, total body irradiation candidates with BCR before 6 months post-tisagenlecleucel or with NGS positivity at 1 or 3 months post-tisagenlecleucel, although there was variability about whether to proceed to HSCT directly or give intervening therapy prior to HSCT. The proportion of respondents recommending HSCT for BCR or NGS positivity decreased in those with a history of HSCT, non-TBI-candidates, or trisomy 21. CONCLUSIONS The results of this survey indicate there exists significant practice variability regarding the use of cHSCT as well as interventions for post-tisagenlecleucel BCR or NGS positivity. These results highlight areas for which ongoing clinical trials could inform more standardized practice.
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Comparison of blinatumomab and CAR T-cell therapy in relapsed/refractory acute lymphoblastic leukemia: a systematic review and meta-analysis
Zhai, Y., Hong, J., Wang, J., Jiang, Y., Wu, W., Lv, Y., Guo, J., Tian, L., Sun, H., Li, Y., et al
Expert review of hematology. 2023
Abstract
OBJECTIVES This study evaluated the benefits and risks of patients with refractory or relapsed acute lymphocytic leukemia (R/R ALL) treated with Anti-CD19 chimeric antigen receptor (CAR) T-cell therapy and blinatumomab. METHODS PubMed, Web of Science, Embase, and the Cochrane Library were searched for relevant studies. RESULTS The pooled complete remission (CR) rate and minimal residual disease (MRD) negative rate were 48%, 31% for blinatumomab, and 86% and 80% for CAR T-cell therapy. CONCLUSIONS The CAR T-cell therapy group exhibited a higher likelihood of CR rate than the blinatumomab group in every analysis regardless of adjustment subgroups. CAR T-cell therapy was associated with a significantly prolonged overall survival (OS) and relapse-free survival (RFS) compared with blinatumomab (2-year OS 55% vs 25%; 2-year RFS 40% vs 22%). CAR T-cell therapy was more effective for achieving CR and bridging to allogeneic hematopoietic stem cell transplantation (allo-SCT) than blinatumomab (2-year OS 75% vs. 57%). An emerging role for blinatumomab is as a bridging agent pre-SCT and for patients who achieve an MRD-negative state pre-SCT, post-SCT outcomes are expected to be the same as CAR-T. For adverse effects (AEs), blinatumomab was associated with a lower rate of grade ≥ 3 hematological toxicity, CRS, and neurological events.
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Cytoplasmic CD79a is a promising biomarker for B lymphoblastic leukemia follow up post CD19 CAR-T therapy
Chen, M., Fu, M., Wang, A., Wu, X., Zhen, J., Gong, M., Zhang, X., Yue, G., Du, Q., Zhao, W., et al
Leukemia & lymphoma. 2022;63(2):426-434
Abstract
Minimal residual disease (MRD) detection is an important prognostic parameter in patients with refractory or relapsed B-cell acute lymphoblastic leukemia (R/R B-ALL). CD79a has been reported to exhibit a high degree of linage-specificity for B-cell differentiation, with a specificity of 88% and a sensitivity of 100%. In this study, we investigated the efficiency and prognostic role of cytoplasmic CD79a (cCD79a) antibody-gated multicolor flow cytometry (MFC) in MRD detection in patients with B-ALL who received CD19-targeted chimeric antigen receptor (CAR) T-cell therapy bridging to allogeneic hematopoietic stem cell transplantation (allo-HSCT). The retrospective analysis was carried on to 59 patients who accepted allo-HSCT after CD19-CAR-T infusion from June 2016 to May 2017. The MFC MRD statuses before and after allo-HSCT were both strongly correlated with the transplantation prognosis, the MFC panel with cCD79a gating can effectively monitor MRD after CD19 CAR T-cell therapy and predict the prognosis after allo-HSCT. Trial registration: ClinicalTrials#: ChiCTR-IIh-16008711.gov: NCT03173417. Registered 30 May 2017 - retrospectively registered, https://www.clinicaltrials.gov/.
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Comparable outcomes in patients with B-cell acute lymphoblastic leukemia receiving haploidentical hematopoietic stem cell transplantation: Pretransplant minimal residual disease-negative complete remission following chimeric antigen receptor T-cell therapy versus chemotherapy
Yang, T. T., Meng, Y., Kong, D. L., Wei, G. Q., Zhang, M. M., Wu, W. J., Shi, J. M., Luo, Y., Zhao, Y. M., Yu, J., et al
Frontiers in immunology. 2022;13:934442
Abstract
INTRODUCTION Chimeric antigen receptor (CAR) T-cell (CAR-T) therapy followed by haploidentical hematopoietic stem cell transplantation (haplo-HSCT) markedly improves the long-term survival of patients with refractory/relapsed (R/R) B-cell acute lymphoblastic leukemia (B-ALL). METHODS We performed a parallel comparison of transplant outcomes in 168 B-ALL patients undergoing haplo-HSCT after achieving minimal residual disease (MRD)-negative complete remission (CR) from CAR-T therapy (n = 28) or chemotherapy (n = 140) between January 2016 and August 2021. We further divided the chemotherapy group into the first CR group (chemo+CR1, n = 118) and a second or more CR group (chemo+≥CR2, n = 22). RESULTS With a median follow-up period of 31.0 months, the 2-year overall survival (OS), leukemia-free survival (LFS), non-relapse mortality (NRM), and relapse rates in the CAR-T and chemotherapy groups did not differ significantly (OS, 87.9% vs. 71.5 %; LFS, 72.0% vs. 66.8%; NRM, 3.9% vs. 13.7%; relapse, 24.1% vs. 19.4%). Multivariate analysis confirmed that ≥CR2 at transplantation following chemotherapy was an independent risk factor associated with poor OS (hazard ratio (HR) 4.22 [95% CI, 1.34-13.293], p = 0.014) and LFS (HR 2.57 [95% CI, 1.041-6.343], p = 0.041). The probabilities of OS and LFS at 2 years in the CAR-T group were comparable to those in the chemo+CR1 group but significantly higher than those in the chemo+≥CR2 group (OS, 87.9% vs. 37.8%, p = 0.007; LFS, 72.0% vs. 41.7%, p = 0.043). No significant differences in the incidences of NRM were noted among the three groups. CONCLUSIONS Our results demonstrated that patients with R/R B-ALL receiving haplo-HSCT after CAR-T therapy achieved comparable outcomes to patients transplanted post-chemotherapy-based MRD-negative CR1, without increased risk of transplant-related mortality and toxicity.