Background We aim to investigate whether the myelodysplastic syndrome stem cell (MDS-SC)-based assay could be used to predict relapse and survival after treatment in patients with MDS with excess blasts (MDS-EB). Methods A total of 143 cases receiving allografting were prospectively enrolled. A single-cell proteogenomic technique was used to evaluate the characteristics of CD34 + MDS subsets. These cells were detected using multiparameter flow cytometry (MFC) at diagnosis and post-treatment. Results The MDS-SCs could be detected based on CD34 + CD38 − cocktail + immunophenotype by MFC, which exhibit greater stemness and quiescence than CD34 + CD38 − CD33 + MDS cells, CD34 + CD38 − CD45RA + MDS cells, and CD34 + CD38 − CD123 + MDS cells. A high-level of CD34 + CD38 − cocktail + MDS-SCs (≥ 0.1064%) before allograft independently predicted 3-year cumulative incidence of relapse (CIR, P < 0.001). No association of MDS cells evaluated by the traditional MFC method before transplantation with relapse was observed. Patients with positive CD34 + CD38 − cocktail + MDS-SCs (≥ 0.0081%) after allografting experienced a higher 3-year CIR (40.4% vs. 6.5%, P < 0.001) and lower disease-free survival (DFS, 57.4% vs . 85.1%, P < 0.001) than those with negative CD34 + CD38 − cocktail + MDS-SCs (< 0.0081%). Multivariate analysis revealed that positive CD34 + CD38 cocktail + MDS-SCs after transplantation independently predicted the CIR ( P < 0.001) and DFS ( P < 0.001). Patients with traditional MFC MRD positivity after allografting also had a higher CIR (60.0% vs. 12.8%, P < 0.001) and lower DFS (40.0% vs. 80.2%, P < 0.001) than those with negative results. Compared with the traditional MFC method, the MDS-SC-based assay has higher sensitivity and C-index for disease burden determination and MRD detection. Conclusions Our data suggest the superiority of the MDS-SC-based assay over the traditional MFC method for outcome prediction in MDS-EB patients.

Background:Donor selection strategies for allogeneic hematopoietic cell transplantation (HCT) have evolved with the increasing use of haploidentical transplantation. However, contemporary patterns of donor and stem cell source selection according to disease category in the Asia-Pacific (AP) region remain insufficiently characterized. Methods:Aggregated data from the APBMT Activity Survey 2022-2023 were analyzed to evaluate donor type and stem cell source distributions for allogeneic HCT. Donors were categorized as HLA-identical sibling, haploidentical (including other related donors), or unrelated donor. Stem cell sources were classified as bone marrow (BM), peripheral blood (PB), cord blood (CB), or mixed graft sources. Malignant and non-malignant diseases were compared, and disease-specific analyses were performed for acute myeloid leukemia, myelodysplastic syndrome/myeloproliferative neoplasms, severe aplastic anemia, and hemoglobinopathy. Sensitivity analyses excluding data from China were conducted. Results:Donor selection differed between malignant and non-malignant diseases, with haploidentical donors accounting for approximately 45%-60% of allogeneic HCTs, followed by unrelated donors (20%-30%) and HLA-identical sibling donors (15%-25%). Regarding stem cell source, PB was the predominant source across disease categories, accounting for approximately 60%-70% of allogeneic HCTs. BM accounted for approximately 5%-17% of transplants, with somewhat higher use in non-malignant diseases. CB accounted for approximately 10%-12% of transplants in malignant diseases and 3%-4% in non-malignant diseases. These patterns were consistent in disease-specific analyses; however, exclusion of China resulted in a relative decrease in haploidentical transplantation and an increase in unrelated donor use, particularly in malignant diseases, as well as a marked reduction in mixed graft sources with a corresponding increase in bone marrow use. Despite these shifts, the overall predominance of peripheral blood as the stem cell source and the disease-specific trends were maintained. Conclusions:Across AP region, donor and stem cell source selection for allogeneic HCT demonstrates modest but consistent disease-specific differences, reflecting adaptation of transplantation strategies to disease context in contemporary clinical practice.

Acute myocardial infarction (MI) is a relatively rare but life-threatening complication of allogeneic hematopoietic stem cell transplantation (allo-HSCT). Information regarding the clinical characteristics, outcomes, and prognostication of post-transplant MI is lacking. We conducted a nationally representative cohort study at 34 centers in China. Patients with MI were retrospectively identified among those who underwent allo-HSCT. The diagnosis and classification of MI were reviewed according to established guidelines. One hundred thirteen patients were analyzed, including 23 patients with T1MI, 87 patients with T2MI, and three patients with T3MI. Patients with T2MI had a significantly higher mortality rate. Thrombotic microangiopathy (TMA) frequently coexisted with T2MI and adversely affected the overall survival. Disease relapse or progression, a platelet count <20 × 109/L, active TMA at MI onset, and Killip class 3-4 were identified as independent risk factors for 2-month mortality. We divided these patients into a low-risk group (without risk factors), an intermediate-risk group (1-2 risk factors), and a high-risk group (3-4 risk factors). Significantly different 2-month mortality rates were observed across these groups (11.1 %, 59.3 %, and 100.0 %, respectively). Available angiographic imaging data and antiplatelet therapy after MI onset may be associated with improved outcome, but the survival benefits and optimized medication use in patients with post-transplant MI require further validation. These findings may facilitate refined monitoring and management strategies of MI in the post-transplant population.

Limited data are available on bronchiolitis obliterans syndrome (BOS) in children undergoing haploidentical hematopoietic cell transplantation (haplo-HCT). To describe the clinical characteristics, treatment response, and factors influencing first-line treatment response in BOS patients undergoing haplo-HCT using a granulocyte colony-stimulating factor/antithymocyte globulin-based protocol. We conducted a single-center retrospective study including 60 pediatric patients with BOS at Peking University People's Hospital between January 2016 and December 2022. BOS was diagnosed at a median of 12.85 (interquartile range: 10.52 to 16.82) mo after haplo-HCT, and patients were followed for a median of 28.4 (95% confidence interval [CI]: 22.9 to 37.8) mo from BOS diagnosis. Among the 52 evaluable patients with long-term follow-up, the overall response rate (ORR) for first-line treatment was 33%. For 15 evaluable patients receiving second-line treatment, the ORR was 13%, resulting in a total ORR of 46% across first-line and second-line therapy. Three significant independent predictors of first-line treatment response were identified: NIH lung score 3 at baseline (odds ratio [OR], 0.112; 95% CI, 0.014 to 0.866; P = .036), disease status of greater than or equal to second complete remission at haplo-HCT (OR, 0.034; 95% CI, 0.002 to 0.488; P = .013), and a duration of ≥12.85 mo from haplo-HCT to BOS diagnosis (OR, 9.890; 95% CI, 1.725 to 56.692; P = .010). Pulmonary function trajectories showed that patients with baseline NIH lung scores of 2 or 3 experienced a more pronounced decline in percent of predicted FEV1 after BOS diagnosis compared to those with a score of 1. These findings highlight the importance of early diagnosis of BOS and initiating treatment for patients with early stages of the disease.

Therapy-related acute myeloid leukemia (t-AML), which develops after cytotoxic therapy, has a poorer prognosis. Although allogeneic hematopoietic stem cell transplantation (allo-HSCT) is a potential cure, its efficacy varies among patients. In this retrospective study, we analyzed 154 patients with t-AML who underwent hematopoietic stem cell transplantation (HSCT) at our institution to determine their clinical characteristics and develop a prognostic nomogram. The median ages at t-AML diagnosis prior disease diagnosis was 42 and 39 years, respectively. Multivariate analysis identified key prognostic indicators: leukocyte count at AML diagnosis >= 7 x 10<^>9/L, genetic abnormalities before HSCT, platelet engraftment >= 28 days, age at prior disease >= 45 years, and relapse of prior disease. We developed a prognostic nomogram for LGPAR by categorizing patients into low, medium, and high-risk groups. The 3-year and 5-year overall survival (OS) rates for these groups were 92.6 %, 84.4 %, 14 %, and 92.6 %, 76.6 %, and 7 %, respectively. The 3-year and 5-year relapse-free survival (RFS) rates were 80 %, 75.9 %, 10.7 % and 80 %, 72.6 %, and 10.7 % for the respective risk groups. The 3-year and 5-year non-relapse mortality (NRM) rates were 0 %, 5.6 %, 63.3 % and 0 %, 9.3 %, and 63.3 % for these groups, respectively. This novel prognostic nomogram culminates in the development of a clinical decision-support tool for patients with t-AML undergoing allo-HSCT.

Immune thrombocytopenia (ITP) is characterized by impaired platelet production and increased platelet destruction. Zanubrutinib is a highly selective next-generation Bruton tyrosine kinase (BTK) inhibitor that may reduce autoantibody production and reduce macrophage Fcγ receptor-mediated platelet destruction. In this single-arm, phase II study, we aimed to assess the efficacy and safety of zanubrutinib in corticosteroid-resistant or relapsed ITP. All patients received 80 mg zanubrutinib once daily for 6 weeks followed by a 20-week safety follow-up period. The primary endpoint was overall response (OR), defined as at least two consecutive platelet counts of at least 30 × 109/L, at least a 2-fold increase in the baseline count, the absence of bleeding, and no need for rescue therapy at 4 weeks. The trial was registered with ClinicalTrials.gov, number NCT05279872. Between January 1, 2022 and October 30, 2022, 20 patients were enrolled. The median platelet count was 19 (10-25) × 109/L at the time of enrollment. Participants had received a median of 4 (3-6) different therapies for ITP. Eleven (55%, 95% CI: 31.5%-76.9%) patients achieved an OR to the intervention. Two (10%) patients achieved a complete response. At the 6-month follow-up, a sustained response was achieved in seven (35.0%, 95% CI: 15.4%-59.2%) patients. There were no grade 4 or worse adverse events or treatment-related deaths. The most common adverse events were upper respiratory tract infection (in 25% of the patients). Zanubrutinib showed an encouraging response rate and tolerability, supporting its therapeutic potential for the treatment of ITP. Trial Registration: ClinicalTrials.gov identifier: NCT05279872.

Allogeneic hematopoietic stem cell transplantation (HSCT) is the only curative strategy for patients with chronic myelomonocytic leukemia (CMML). However, few reports have investigated the outcomes of patients receiving haploidentical HSCT. To this end, we included 117 patients with haploidentical donors (HID) and 75 patients with matched related donors (MRD) from 28 centers across China to explore the prognostic impact of different transplantation modalities. We found no significant difference between these two groups in terms of event-free survival (EFS, p = .211), overall survival (OS, p = .503), cumulative incidence of relapse (CIR, p = .076) or non-relapse mortality (NRM, p = .794). The predominance of peripheral blood (PB) graft source over bone marrow and PB since 2020 may have contributed to the worse outcomes in the MRD group. Moreover, CMML-specific prognostic scoring system (CPSS) lower-risk patients benefited more from the HID modality with superior EFS (p = .006). Multivariate analysis indicated that advanced age (p = .013), anemia at diagnosis (p = .010), and donor relationship (parent-to-child, p = .013) were independently associated with worse EFS in the HID group. Our data suggested that HID was comparable to MRD in CMML. However, under certain conditions, such as CPSS lower-risk ones, HID was preferred.

This study evaluated the kinetics of KMT2A-r during chemotherapy and its impact on allogeneic haematopoietic stem cell transplantation (allo-HSCT) outcomes. KMT2A-r was assessed post-induction (MRD1), after the first (MRD2) and second (MRD3) consolidations and pre-transplant (MRD4) in 52 patients with acute myeloid leukaemia (AML). KMT2A-r significantly decreased from diagnosis to MRD2 (p < 0.001 for diagnosis vs. MRD1; p = 0.019 for MRD1 vs. MRD2). The incidence of KMT2A-r negativity (57.5%) peaked at MRD2. KMT2A-r status at each time point significantly affected post-transplant outcomes. Cluster analysis identified four KMT2A-r kinetic profiles: persistently negative (-/-), turned negative at transplant (+/-), turned positive at transplant (-/+) and persistently positive (+/+). The (-/-) group had the best outcomes, with a cumulative incidence of relapse (CIR) of 13.0%, overall survival (OS) of 82.0% and leukaemia-free survival (LFS) of 81.7%. The (+/+) group had the worst prognosis, with a CIR of 58.8%, OS of 29.4% and LFS of 23.5%. KMT2A dynamics were an independent risk factor for CIR (Hazard ratio [HR] = 11.070, 95%CI 2.395-51.165, p = 0.002), LFS (HR = 9.316, 95%CI 2.656-32.668, p < 0.001) and OS (HR = 7.172, 95%CI 1.999-25.730, p = 0.003). In conclusion, KMT2A-r status after chemotherapy and its kinetics are significant HSCT prognostic indicators.

Bloodstream infection (BSI) is a frequent but lethal complication in hematologic patients with febrile neutropenia (FN). However, blood culture (BC) only detects an organism in 20%–30% of patients with FN. We aimed to evaluate the diagnostic performance of metagenomic next-generation sequencing (mNGS) as a first-line diagnostic method in BSI. This study was prospectively performed in 4 Chinese hematologic centers. In patients aged ≥15 years with hematologic diseases, peripheral blood specimens were collected per patient for simultaneous BC and mNGS at the onset of FN. The clinical physician and mNGS analysis team were double-blinded, and the adjudication of the clinical diagnosis was evaluated by another expert panel of 4 specialists. The primary endpoint of this study was the diagnostic performance of mNGS. This study was registered on ClinicalTrials.gov. Three hundred FN events were enrolled, including 62 definite BSI, 61 probable BSI, 116 infectious FN other than BSI, 55 noninfectious FN events, and 6 FN of indeterminate cause. Among 62 definite BSI cases, mNGS identified causative pathogens in 59 (95.2%). Concurrent BC initially detected pathogens in 59 cases, and 3 additional pathogens consistent with mNGS were later identified in repeated BC testing. The sensitivity, specificity, positive predictive value, and negative predictive value of mNGS were 95.2%, 94.6%, 95.2%, and 94.6%, respectively. The diagnostic time of mNGS was significantly shorter than that of BC (39.7 ± 15.0 vs 119.8 ± 31.9 hours, P < .0001). The findings suggest that the mNGS approach has excellent diagnostic performance for the first-line diagnosis of BSI in patients with FN. The study will promote early diagnosis and better management of the patients.

Background: The level of measurable residual disease (MRD) before and after transplantation is related to inferior transplant outcomes, and post-hematopoietic stem cell transplantation measurable residual disease (post-HSCT MRD) has higher prognostic value in determining risk than pre-hematopoietic stem cell transplantation measurable residual disease (pre-HSCT MRD). However, only a few work has been devoted to the risk factors for positive post-HSCT MRD in patients with acute lymphoblastic leukemia (ALL). This study evaluated the risk factors for post-HSCT MRD positivity in patients with ALL who underwent allogeneic hematopoietic stem cell transplantation (allo-HSCT).Methods: A total of 1683 ALL patients from Peking University People’s Hospital between January 2009 and December 2019 were enrolled to evaluate the cumulative incidence of post-HSCT MRD. Cox proportional hazard regression models were built for time-to-event outcomes. Multivariable analysis was performed to determine independent influencing factors from the univariable analysis.Results: Both in total patients and in T-cell ALL or B-cell ALL, pediatric or adult, human leukocyte antigen-matched sibling donor transplantation or haploidentical SCT subgroups, positive pre-HSCT MRD was a risk factor for post-HSCT MRD positivity (P <0.001 for all). Disease status (complete remission 1 [CR1]vs. ≥CR2) was also a risk factor for post-HSCT MRD positivity in all patients and in the B cell-ALL, pediatric, or haploidentical SCT subgroups (P = 0.027;P = 0.003;P = 0.035;P = 0.003, respectively). A risk score for post-HSCT MRD positivity was developed using the variables pre-HSCT MRD and disease status. The cumulative incidence of post-HSCT MRD positivity was 12.3%, 25.1%, and 38.8% for subjects with scores of 0, 1, and 2–3, respectively (P <0.001). Multivariable analysis confirmed the association of the risk score with the cumulative incidence of post-HSCT MRD positivity and relapse as well as leukemia-free survival and overall survival.Conclusion: Our results indicated that positive pre-MRD and disease status were two independent risk factors for post-HSCT MRD positivity in patients with ALL who underwent allo-HSCT.

Objective: Allogeneic hematopoietic stem cell transplantation(allo-HSCT) is the only potentially curative method for treating myelodysplastic syndrome(MDS). Post-HSCT measurable residual disease(post-HSCT MRD) is associated with inferior transplant outcomes. In this prospective study, we aimed to investigate the prognostic value of post-HSCT MRD in relapse prediction in MDS.Methods: A total of 166 patients diagnosed with MDS were prospectively enrolled in this study. The KaplanMeier method was used to calculate the survival probabilities. Potential risk factors for outcomes after transplantation were evaluated through univariate and multivariate Cox regression models.Results: For patients with negative and positive post-HSCT MRD, the cumulative incidence of relapse(CIR)and disease-free survival(DFS) at 3 years were 5.9% and 69.6%(P<0.001) and 82.7% and 26.1%(P<0.001),respectively. In the multivariate analysis, post-HSCT MRD(HR=22.801, P<0.001) and Revised International Prognostic Scoring System(IPSS-R) risk stratification(HR=4.346, P=0.003) were independently correlated with relapse. A scoring system for relapse prediction was built based on post-HSCT MRD and IPSS-R stratification.The cumulative incidence of relapse at 3 years was 1.1%, 15.8%, and 91.7% for patients with scores of 0, 1, and 2,respectively(P<0.001).Conclusions: Our results demonstrated both post-HSCT MRD and IPSS-R scores were independent prognostic factors for OS, DFS, and relapse for MDS patients after allo-HSCT. The risk score system could better predict transplant outcomes and refine the risk stratification than alone in patients with MDS.

In this study, we explored the ability of leukemia stem cell (LSC)-based method and traditional multiparameter flow cytometry (MFC) assay to predict leukemia relapse after long-term follow-up. 360 AML patients who received allografts between July 2018 and November 2019 were prospectively enrolled. Patients with positive measurable residual disease (MRD) based on CD34(+)CD38(-)cocktail(+) LSCs (>= 0.004%) exhibited a greater 5-year cumulative incidence of relapse (CIR) (49.7% vs. 8.5%, P < 0.001), inferior leukemia-free survival (LFS) (48.2% vs. 84.4%, P < 0.001) and inferior overall survival (OS) (59.7% vs. 82.8%, P < 0.001), than did patients without CD34(+)CD38(-)cocktail(+) LSCs (<0.004%). Patients with detectable traditional MFC-MRD exhibited a greater CIR than patients without MRD (45.8% vs. 10.9%, P < 0.001), thereby leading to decreased LFS (54.2% vs. 81.9%, P < 0.001) and decreased OS (56.0% vs. 85.9%, P = 0.001). Compared with traditional MFC-MRD, LSCs-based MRD assay demonstrated high sensitivity (52.4% vs. 33.3%), high C-index (0.72 vs. 0.65) and high Youden index (0.44 vs. 0.27). The median time from LSCs positivity to relapse was longer than the median time from traditional MRD positivity to relapse (144 days vs. 65 days, P = 0.012). Our data confirmed the superiority of the LSC-based MRD assay compared to traditional MFC MRD methods in AML patients who received allografts after long-term follow-up.

A second transplantation is almost the only salvage for patients encountering graft failure (GF) following first allogeneic stem cell transplantation. However, there were no standard protocols for second transplantations, and the role of changing donors remained controversial. We retrospectively studied 272 consecutive patients from 18 Chinese centers undergoing second transplantations due to GF, aiming to assess the impact of changing donors and the factors affecting second transplantation outcomes. The primary endpoint was neutrophil engraftment. Other endpoints included platelet engraftment, graft-versushost disease (GvHD), transplant-related mortality (TRM), relapse, and survival. Of the 272 patients, 193 (71.0%) patients experienced primary GF, and 70.6% (192) used a different second donor. Neutrophil engraftment was achieved in 218 (86.3%) patients by day (d)28, and platelet engraftment was achieved in 164 (70.0%) patients by d100. The 3-year cumulative incidence of acute GvHD, chronic GvHD, relapse, and TRM were 43.5%, 27.8%, 15.6%, and 44.6%, respectively. The 1-year and 3-year overall survival (OS) were 56.1% and 49.5%, respectively. Compared to using the same donor, changing donors significantly improved neutrophil engraftment (92.4% vs. 71.4%, P<0.001) and platelet engraftment (76.9% vs. 51.8%, P<0.001), 1-year TRM (34.8% vs. 56.3%, P<0.001), and OS (61.9% vs. 42.7%, P<0.001). Subgroup analysis confirmed engraftment benefit of changing donor in primary GF (P<0.001), but not in secondary GF (P=0.346). This is the largest multicenter study of second transplantations for GF, suggesting that changing donors might be critical for engraftment and survival after second transplantation.

BackgroundMelphalan formulated with modified cyclodextrin (β-cyclodextrin sulfobutyl ether sodium [BSES]) is widely used before autologous stem cell transplantation (ASCT) in patients with multiple myeloma (MM) because of its favorable solubility and stability versus conventional melphalan, but the efficacy and safety data on Chinese patients with MM who subsequently underwent ASCT are still limited.MethodsIn this prospective, open-label, non-randomized, interventional study, a total of 67 MM patients who were eligible for ASCT were enrolled and assigned to receive 200 mg/m2 of Melphalan in two divided doses of 100 mg/m2 on Days -3 and -2 before ASCT on Day 0. We evaluated the efficacy, safety and pharmacokinetics (PK) of a prolonged infusion of high-dose BSES-melphalan as the conditioning treatment in the patients.ResultsOverall, 67 patients received melphalan with the median infusion time of 136 min. All patients achieved myeloablation with a median time of 5 days. Median time to neutrophil and platelet engraftments was 11 and 12 days after ASCT, respectively. Within the 65 evaluable patients, 18 patients (27.7%) achieved stringent complete response, 21 (32.3%) achieved complete response, 18 (27.7%) achieved very good partial response, and 3 (4.6%) achieved partial response. No treatment-related mortality (TRM) or adverse events leading to study withdrawal were identified. Prolonged infusion resulted in a lower Cmax but comparable AUCs.ConclusionsHigh-dose BSES-melphalan as a conditioning medicine is effective and safe in Chinese patients with MM before ASCT. Prolonging infusion duration may improve the safety without compromising efficacy.

Background: Patients with lysine methyltransferase 2a (KMT2A)-rearranged (KMT2A-r) acute myeloid leukemia (AML) are assigned to intermediate-risk and adverse-risk categories at diagnosis. However, the value of molecular measurable residual disease (MRD) status in patients who have KMT2A-r AML before allogeneic hematopoietic stem cell transplantation (allo-HSCT) in adult cohorts has rarely been evaluated. Methods: Patients with KMT2A-r AML who achieved complete remission and subsequently underwent allo-HSCT between January 2015 and January 2023 were included in this analysis. Real-time quantitative polymerase chain reaction was used to detect molecular MRD in bone marrow samples. The end points were overall survival (OS), leukemia-free survival (LFS), the cumulative incidence of relapse (CIR), and nonrelapse mortality (NRM). Results: Pretransplantation molecular MRD was identified in 52 of 125 patients (42%) with KMT2A-r AML. The presence of KMT2A-r MRD was associated with inferior 3-year OS (51% vs. 82%; p < .001), LFS (42% vs. 81%; p < .001), CIR (33% vs. 12%; p < .001), and NRM (11% vs. 5%; p = .12). In multivariate models, molecular MRD status before transplantation independently predicted OS, LFS, and CIR. The survival of adult patients with KMT2A-r AML was heterogeneous, depending on the KMT2A translocation partners, and was more favorable in patients who had t(9;11) and t(10;11) than in those who had t(11;19) and t(6;11). In addition, flow cytometry-based MRD analysis conferred no additional prognostic value to the results of molecular MRD status. Conclusions: Residual KMT2A-r before allo-HSCT independently predicts the risk of survival and relapse, and donor lymphocyte infusion or posttransplantation maintenance therapies should be considered for patients who have AML with detectable molecular MRD.

Background and Objectives:Haploidentical stem cell transplantation (haplo-HSCT) has demonstrated promising results in patients without severe comorbidities. There is also an increasing need for haplo-HSCT in patients with severe comorbidities. However, the high risk of treatment-related mortality (TRM) hindered its extensive application. We aimed to investigate a novel conditioning regimen (Bu/Flu/Cy/ATG) followed by haplo-HSCT in patients with severe comorbidities. Methods:This prospective, single-arm clinical trial was performed at Peking University Institute of Hematology, China. Patients were enrolled if they were (1) diagnosed with acute leukemia, myelodysplastic syndrome (MDS), or chronic myelomonocytic leukemia (CMML); (2) patients with no HLA-matched sibling donor or matched unrelated donor available but with a haplo-HSCT donor; (3) patients with hematopoietic cell transplantation comorbidity index (HCT-CI) scores ≥3. The primary endpoint was 2-year TRM. Results:From June 2018 to November 2022, a total of 72 patients were enrolled. All patients achieved neutrophil engraftment. The cumulative incidence of grade II-IV acute graft-versus-host disease (aGVHD) at day 100 was 20.8%. The cumulative incidences of cytomegalovirus (CMV) viremia and Epstein‒Barr (EB) viremia at day 100 were 72.2% and 31.9%, respectively. The cumulative incidence of 2-year TRM was 25.1%. The cumulative incidence of 2-year relapse was 8.6%. The probabilities of 2-year overall survival and leukemia-free survival were 71.9% and 65.6%, respectively. Conclusion:This study suggested that a novel conditioning regimen followed by haploidentical HSCT might be a promising option for patients with severe comorbidities. The study was registered as a clinical trial (NCT03412409).

[This corrects the article DOI: 10.31547/bct-2024-020.].