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Cost-Effectiveness of Reduced-Intensity Allogeneic Hematopoietic Cell Transplantation for Older Patients With High-Risk Myelodysplastic Syndrome: Analysis of BMT CTN 1102
Saber, W., Bansal, A., Li, L., Scott, B. L., Sangaralingham, L. R., Thao, V., Roth, J. A., Wright, W., Steuten, L. M. G., Pidala, J. A., et al
JCO oncology practice. 2024;:Op2300413
Abstract
PURPOSE BMT CTN 1102 was a phase III trial comparing reduced-intensity allogeneic hematopoietic cell transplantation (RIC alloHCT) to standard of care for persons with intermediate- or high-risk myelodysplastic syndrome (MDS). We report results of a cost-effectiveness analysis conducted alongside the clinical trial. METHODS Three hundred eighty-four patients received HCT (n = 260) or standard of care (n = 124) according to availability of a human leukocyte antigen-matched donor. Cost-effectiveness was calculated from US commercial and Medicare perspectives over a 20-year time horizon. Health care utilization and costs were estimated using propensity score-matched cohorts of HCT recipients in the OptumLabs Data Warehouse (age 50-64 years) and Medicare (age 65 years and older). EuroQol 5 Dimension (EQ-5D) surveys of trial participants were used to derive health state utilities. RESULTS Extrapolated 20-year overall survival for those age 50-64 years was 29% for HCT (n = 105) versus 13% for usual care (n = 44) and 31% for HCT (n = 155) versus 12% for non-HCT (n = 80) for those age 65 years and older. HCT was more effective (+2.36 quality-adjusted life-years [QALYs] for age 50-64 years and +2.92 QALYs for age 65 years and older) and more costly (+$452,242 in US dollars (USD) for age 50-64 years and +$233,214 USD for age 65 years and older) than usual care, with incremental cost-effectiveness ratios of $191,487 (USD)/QALY and $79,834 (USD)/QALY, respectively. For persons age 50-64 years, there was a 29% chance that HCT was cost-effective using a willingness-to-pay (WTP) threshold of $150K (USD)/QALY and 51% at a $200K (USD)/QALY. For persons age 65 years and older, the probability was 100% at a WTP >$150K (USD)/QALY. CONCLUSION Among patients age 65 years and older with high-risk MDS, RIC HCT is a high-value strategy. For those age 50-64 years, HCT is a lower-value strategy but has similar cost-effectiveness to other therapies commonly used in oncology.
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Finding a balance in reduced toxicity hematopoietic stem cell transplantation for thalassemia: role of infused CD3+ cell count and immunosuppression
Meissner, B., Lang, P., Bader, P., Hoenig, M., Müller, I., Meisel, R., Greil, J., Sauer, M. G., Metzler, M., Corbacioglu, S., et al
Bone marrow transplantation. 2024
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Editor's Choice
Abstract
We performed a retrospective analysis on 124 patients with transfusion-dependent thalassemia who were registered in the German pediatric registry for stem cell transplantation. All patients underwent first allogeneic hematopoietic stem cell transplantation (HSCT) between 2011 and 2020 and belonged mainly to Pesaro risk class 1-2. Four-year overall (OS) and thalassemia-free survival (TFS) were 94.5% ± 2.9% and 88.0% ± 3.4% after treosulfan-fludarabine-thiotepa- and 96.9% ± 3.1% (P = 0.763) and 96.9% ± 3.1% (P = 0.155) after busulfan-fludarabine-based conditioning. Mixed chimerism below 75% occurred predominantly in treosulfan-based regimens (27.5% versus 6.2%). OS and TFS did not differ significantly between matched sibling, other matched family and matched unrelated donor (UD) HSCTs (OS: 100.0%, 100.0%, 96.3% ± 3.6%; TFS: 96.5% ± 2.4%, 90.0% ± 9.5%, 88.9% ± 6.0%). However, mismatched UD-HSCTs performed less favorable (OS: 84.7% ± 7.3% (P = 0.029); TFS: 79.9% ± 7.4% (P = 0.082)). We generated a scoring system reflecting the risk to develop mixed chimerism in our cohort. The main risk-reducing factors were a high CD3+ cell count (≥6 × 10(7)/kg) in the graft, busulfan-conditioning, pre-conditioning therapy and low-targeted ciclosporin A trough levels. Acute GvHD grade III-IV in treosulfan-based concepts predominantly occurred in patients with UD and reduced GvHD prophylaxis but not in the context of high CD3+ cell doses. Taken together, this information might be used to develop more risk-adapted HSCT regimens for thalassemia patients.
PICO Summary
Population
Children and young adults with transfusion-dependent thalassemia who underwent first allogeneic transplant between 2011 and 2020 and were registered in the German pediatric registry for stem cell transplantation. (n=124)
Intervention
Treosulfan-fludarabine-thiotepa based conditioning (n=92)
Comparison
Busulfan-fludarabine-based conditioning (n=32)
Outcome
Four-year overall (OS) and thalassemia-free survival (TFS) were 94.5% ± 2.9% and 88.0% ± 3.4% after treosulfan-fludarabine-thiotepa- and 96.9% ± 3.1% and 96.9% ± 3.1% after busulfan-fludarabine-based conditioning. Mixed chimerism below 75% occurred predominantly in treosulfan-based regimens (27.5% versus 6.2%). OS and TFS did not differ significantly between matched sibling, other matched family and matched unrelated donor (UD) HSCTs (OS: 100.0%, 100.0%, 96.3% ± 3.6%; TFS: 96.5% ± 2.4%, 90.0% ± 9.5%, 88.9% ± 6.0%). However, mismatched UD-HSCTs performed less favorable (OS: 84.7% ± 7.3%; TFS: 79.9% ± 7.4%). We generated a scoring system reflecting the risk to develop mixed chimerism in our cohort. The main risk-reducing factors were a high CD3+ cell count (≥6 × 10(7)/kg) in the graft, busulfan-conditioning, pre-conditioning therapy and low-targeted ciclosporin A trough levels. Acute GvHD grade III-IV in treosulfan-based concepts predominantly occurred in patients with UD and reduced GvHD prophylaxis but not in the context of high CD3+ cell doses.
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Alemtuzumab and CXCL9 levels predict likelihood of sustained engraftment after reduced-intensity conditioning HCT
Geerlinks, A. V., Scull, B., Krupski, C., Fleischmann, R., Pulsipher, M. A., Eapen, M., Connelly, J. A., Bollard, C. M., Pai, S. Y., Duncan, C. N., et al
Blood advances. 2023;7(14):3725-3734
Abstract
Overall survival after reduced-intensity conditioning (RIC) allogeneic hematopoietic cell transplantation (HCT) using alemtuzumab, fludarabine, and melphalan is associated with high rates of mixed chimerism (MC) and secondary graft failure (GF). We hypothesized that peritransplantation alemtuzumab levels or specific patterns of inflammation would predict these risks. We assessed samples from the Bone Marrow Transplant Clinical Trials Network 1204 (NCT01998633) to study the impact of alemtuzumab levels and cytokine patterns on MC and impending or established secondary GF (defined as donor chimerism <5% after initial engraftment and/or requirement of cellular intervention). Thirty-three patients with hemophagocytic lymphohistiocytosis (n = 25) and other IEIs (n = 8) who underwent HCTs with T-cell-replete grafts were included. Patients with day 0 alemtuzumab levels ≤0.32 μg/mL had a markedly lower incidence of MC, 14.3%, vs 90.9% in patients with levels >0.32 μg/mL (P = .008). Impending or established secondary GF was only observed in patients with day 0 alemtuzumab levels >0.32 μg/mL (P = .08). Unexpectedly, patients with impending or established secondary GF had lower CXCL9 levels. The cumulative incidence of impending or established secondary GF in patients with a day 14+ CXCL9 level ≤2394 pg/mL (day 14+ median) was 73.6% vs 0% in patients with a level >2394 pg/mL (P = .002). CXCL9 levels inversely correlated with alemtuzumab levels. These data suggest a model in which higher levels of alemtuzumab at day 0 deplete donor T cells, inhibit the graft-versus-marrow reaction (thereby suppressing CXCL9 levels), and adversely affect sustained engraftment in the nonmyeloablative HCT setting. This trial was registered at www.clinicaltrials.gov as #NCT01998633.
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[Stem Cell Transplantations for Patients with Fanconi Anemia: An Israeli Tertiary Center Experience]
Even-Or, E., Zaidman, I., Najajreh, M., Avni, B., Grisariu, S., Stepensky, P.
Harefuah. 2023;162(1):9-14
Abstract
INTRODUCTION Fanconi anemia (FA) is a rare genetic syndrome characterized by increased chromosomal breakage, congenital anomalies, bone marrow failure and an increased tendency to develop malignancies. Allogeneic hematopoietic stem cell transplantation (HSCT) is the only curative treatment for bone marrow failure and the hematologic malignancies these patients develop. Given the sensitivity of FA patients to chemotherapy and radiation, as to the clinical symptoms of graft versus host disease (GvHD), HSCT in these patients is challenging. Since the mid-nineties, HSCT for FA patients is performed in our center by using the fludarabine based reduced-intensity protocol. AIMS To summarize the results of HSCT for patients with FA using a fludarabine based reduced-intensity conditioning regimen at the Hadassah Medical Center. METHODS This retrospective research is based on the collection and analysis of clinical and laboratory data from the medical records of patients. RESULTS Since June 1996 up till February 2020, 39 patients with FA underwent 43 HSCTs with a fludarabine based protocol at the Hadassah Medical Center. Four patients required a second transplant due to primary engraftment failure. Nine patients (23%) suffered from acute GvHD, four of them severe. Eight patients (20%) developed chronic GvHD, two with an extensive and debilitating disease. Thirty-three (85%) of the patients survived and six died, five shortly after the transplant, and one twenty years later from malignancy. CONCLUSIONS Our results show high survival rates with low rates of engraftment failure and reasonable rates of GvHD. DISCUSSION As of today, there is an effective and safe treatment for patients with FA who require HSCT by using a fludarabine-based reduced-intensity conditioning regimen, with high survival rates and few complications.
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Treosulfan Exposure Predicts Thalassemia-free Survival In Patients With Beta Thalassemia Major (TM) Undergoing Allogeneic Hematopoietic Cell Transplantation
Pai, A. A., Mohanan, E., Panetta, J. C., Kulkarni, U. P., Stallon Illangeswaran, R. S., Balakrishnan, B., Jayaraman, A., Edison, E. S., Kavitha, M. L., Devasia, A. J., et al
Clinical pharmacology and therapeutics. 2023
Abstract
A toxicity-reduced conditioning regimen with Treosulfan, Fludarabine, and Thiotepa in patients with high-risk β- thalassemia major has significantly improved HCT outcomes. However, complications resulting from regimen-related toxicities (RRTs), mixed chimerism, and graft rejection remain a challenge. We evaluated the dose-exposure-response relationship of Treosulfan and its active metabolite S, S-EBDM, in a uniform cohort of patients with β-thalassemia major to identify whether therapeutic drug monitoring (TDM) and dose adjustment of Treosulfan is feasible. Plasma Treosulfan/S, S-EBDM levels were measured in seventy-seven patients using a validated LC-MS/MS method, and the PK parameters were estimated using nlmixr2. The influence of Treosulfan & S, S-EBDM exposure, and GSTA1/NQO1 polymorphisms on graft rejection, RRTs, chimerism status, and 1-year Overall Survival (OS), and Thalassemia Free Survival (TFS) were assessed. We observed that Treosulfan exposure was lower in patients with graft rejection than those without (1655 vs. 2037 mg*h/L, p=0.07). Pharmacodynamic modeling analysis to identify therapeutic cut-off revealed that Treosulfan exposure ≥1660 mg*hr/L was significantly associated with better 1-year TFS (97% vs. 81%, p=0.02) and a trend to better 1-year OS (90% vs. 69%, p=0.07). Further, multivariate analysis adjusting for known PreHCT risk factors also revealed Treosulfan exposure <1660mg*h/L (HR=3.23; 95% CI=1.12-9.34; p=0.03) and GSTA1*B variant genotype (HR=3.75; 95% CI=1.04-13.47; p=0.04) to be independent predictors for inferior 1-year TFS. We conclude that lower Treosulfan exposure increases the risk of graft rejection and early transplant-related mortality affecting TFS. As no RRTs were observed with increasing Treosulfan exposure, TDM-based dose adjustment could be feasible and beneficial.
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Excellent outcome of stem cell transplantation for sickle cell disease
Vallée, T., Schmid, I., Gloning, L., Bacova, M., Ahrens, J., Feuchtinger, T., Klein, C., Gaertner, V. D., Albert, M. H.
Annals of hematology. 2023
Abstract
Many sickle cell disease (SCD) patients lack matched family donors (MFD) or matched unrelated donors (MUD), implying haploidentical donors (MMFD) as a logical donor choice. We used a reduced toxicity protocol for all donor types. We included 31 patients (2-22 years) with MFD (n = 15), MMFD (10), or MUD (6) HSCT and conditioning with alemtuzumab/ATG, thiotepa, fludarabine and treosulfan, and post-transplant cyclophosphamide for MMFD. After the initial six patients, treosulfan was replaced by targeted busulfan (AUC 65-75 ng*h/ml). After a median follow-up of 26 months (6-123), all patients are alive and off immunosuppression. Two MMFD patients experienced secondary graft failure with recurrence of SCD, both after treosulfan conditioning. Neither acute GVHD ≥ °III nor moderate/severe chronic GVHD was observed. The disease-free, severe GVHD-free survival was 100%, 100%, and 80% in the MFD, MUD, and MMFD groups, respectively (p = 0.106). There was a higher rate of virus reactivation in MMFD (100%) and MUD (83%) compared to MFD (40%; p = 0.005), but not of viral disease (20% vs 33% vs 13%; p = 0.576). Six patients had treosulfan-based conditioning, two of whom experienced graft failure (33%), compared to 0/25 (0%) after busulfan-based conditioning (p = 0.032). Donor chimerism was ≥ 80% in 28/31 patients (90%) at last follow-up. Reduced toxicity myeloablative conditioning resulted in excellent overall survival, negligible GVHD, and low toxicity among all donor groups in pediatric and young adult patients with SCD.
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Fludarabine-Based Low-Intensity Conditioning for Fanconi Anemia is Associated with Good Outcomes in Aplastic Anemia but not in MDS - a Single-Center Experience
Chattopadhyay, S., Lionel, S., Selvarajan, S., Devasia, A. J., Korula, A., Kulkarni, U., Na, F., Sindhuvi, E., Lakshmi, K. M., Srivastava, A., et al
Mediterranean journal of hematology and infectious diseases. 2023;15(1):e2023039
Abstract
BACKGROUND Hematopoietic stem cell transplantation (HSCT) is the only curative option for patients with Fanconi Anemia (FA) with hematological abnormalities. MATERIALS AND METHODS This is a retrospective analysis of patients with FA who underwent a matched-related donor HSCT. RESULTS Sixty patients underwent 65 transplants between 1999-2021 using a fludarabine-based low-intensity conditioning regimen. The median age at transplant was 11 years (range: 3-37). Aplastic anemia (AA) was the underlying diagnosis in 55 (84.6%), while 8 (12.4%) had myelodysplastic syndrome (MDS) and 2 (3%) had acute myeloid leukemia (AML). The conditioning regimen used was Fludarabine with low-dose Cyclophosphamide for aplastic anemia and Fludarabine with low-dose Busulfan for MDS/AML. Graft versus host disease (GVHD) prophylaxis consisted of Cyclosporine and methotrexate. Peripheral blood was the predominant stem cell graft source (86.2%). Engraftment occurred in all but one patient. The median time to neutrophil and platelet engraftment was 13 days (range: 9-29) & 13 days (range: 5-31), respectively. Day 28 chimerism analysis showed complete chimerism in 75.4 % and mixed chimerism in 18.5%. Secondary graft failure was encountered in 7.7%. Grade II-IV acute GVHD occurred in 29.2%, while Grade III-IV acute GVHD occurred in 9.2%. Chronic GVHD was seen in 58.5% and was limited in most patients. The median follow-up is 55 months (range: 2-144) & the 5-year estimated overall survival (OS) is 80.2 ± 5.1%. Secondary malignancies were noted in 4 patients. The 5-year OS was significantly higher in patients undergoing HSCT for AA (86.6 + 4.7%) as compared to MDS/AML (45.7+16.6%) (p= 0.001). CONCLUSION SCT using a fully matched donor provides good outcomes with low-intensity conditioning regimens in patients with FA who have aplastic marrow.
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Association between the choice of the conditioning regimen and outcomes of allogeneic hematopoietic cell transplantation for myelofibrosis
Murthy, G. S. G., Kim, S., Estrada-Merly, N., Abid, M. B., Aljurf, M., Assal, A., Badar, T., Badawy, S. M., Ballen, K., Beitinjaneh, A., et al
Haematologica. 2023
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Editor's Choice
Abstract
Allogeneic hematopoietic cell transplantation (allo-HCT) remains the only curative treatment for myelofibrosis. However, the optimal conditioning regimen either with reduced intensity conditioning (RIC) or myeloablative conditioning (MAC) is not well known. Using the Center for International Blood and Marrow Transplant Research database, we identified adults aged ≥18 years with myelofibrosis undergoing allo-HCT between 2008-2019 and analyzed the outcomes separately in the RIC and MAC cohorts based on the conditioning regimens used. Among 872 eligible patients, 493 underwent allo-HCT using RIC (Fludarabine/busulfan=166, Fludarabine/melphalan=327) and 379 using MAC (Fludarabine/busulfan=247, Busulfan/cyclophosphamide=132). In multivariable analysis with RIC, Fludarabine/melphalan was associated with inferior overall survival (HR 1.80, 95% CI 1.15-2.81, p=0.009), higher early non-relapse mortality (HR 1.81, 95% CI 1.12-2.91, p=0.01) and higher acute graft versus host disease (GVHD) (grade II-IV- HR 1.45, 95% CI 1.03-2.03, p=0.03; grade III-IV HR 2.21, 95%CI 1.28-3.83, p=0.004) compared to Fludarabine/busulfan. In the MAC setting, Busulfan/cyclophosphamide was associated with a higher acute GVHD (grade II-IV HR 2.33, 95% CI 1.67-3.25, p<0.001; grade III-IV HR 2.31, 95% CI 1.52-3.52, p<0.001) and inferior GVHD-free relapse-free survival (GRFS) (HR 1.94, 95% CI 1.49-2.53, p<0.001) as compared to Fludarabine/busulfan. Hence, our study suggests that Fludarabine/busulfan is associated with better outcomes in RIC (better overall survival, lower early non-relapse mortality, lower acute GVHD) and MAC (lower acute GVHD and better GRFS) in myelofibrosis.
PICO Summary
Population
Adults with myelofibrosis undergoing allogeneic HSCT between 2008-2019 and reported to the CIBMTR database (n=872)
Intervention
Reduced intensity conditioning (RIC) regimens (n=493): fludarabine/busulfan (n=166) or fludarabine/melphalan (n=327)
Comparison
Myeloablative conditioning (MAC) regimens (n=379): fludarabine/busulfan (n=247) or busulfan/cyclophosphamide (n=132).
Outcome
In multivariable analysis with RIC, fludarabine/melphalan was associated with inferior overall survival (HR 1.80, 95% CI 1.15-2.81), higher early non-relapse mortality (HR 1.81, 95% CI 1.12-2.91,) and higher acute graft versus host disease (GVHD) (grade II-IV- HR 1.45, 95% CI 1.03-2.03; grade III-IV HR 2.21, 95%CI 1.28-3.83) compared to fludarabine/busulfan. In the MAC setting, busulfan/cyclophosphamide was associated with a higher acute GVHD (grade II-IV HR 2.33, 95% CI 1.67-3.25; grade III-IV HR 2.31, 95% CI 1.52-3.52) and inferior GVHD-free relapse-free survival (GRFS) (HR 1.94, 95% CI 1.49-2.53) as compared to fludarabine/busulfan.
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Reduced intensity hematopoietic stem cell transplantation for myelofibrosis in accelerated-phase
Gagelmann, N., Wolschke, C., Salit, R. B., Schroeder, T., Ditschkowski, M., Panagiota, V., Cassinat, B., Thol, F., Badbaran, A., Robin, M., et al
Blood advances. 2022
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Editor's Choice
Abstract
Accelerated-phase (AP) myelofibrosis, currently defined by circulating blasts 10-19%, usually confers very high risk for progression and poor outcome. The outcome of hematopoietic stem cell transplantation for AP myelofibrosis has not been evaluated yet. We analyzed the outcome of 349 clinically and genetically annotated patients with primary or secondary myelofibrosis undergoing reduced intensity transplantation, of whom 35 had AP myelofibrosis. In comparison with chronic-phase (CP, <10% blasts), median leukocyte counts were higher, more patients had constitutional symptoms, and RAS mutations were detected more frequently in the AP group. After a median follow-up of 5.9 years, estimated 5-year overall survival was 65% (95% confidence interval, 49-81%) versus 64% (95% confidence interval, 59-69%) for the CP group (P=0.91), and median overall survival was not reached. In terms of relapse-free survival, estimated 5-year outcome for the AP group was 49% (95% confidence interval, 32-67%) versus 55% (95% confidence interval, 50-61%) for the CP group (P=0.65). Estimated 5-year non-relapse mortality was 20% (95% CI, 8-33%) for the AP group versus 30% (95% confidence interval, 24-35%; P=0.25) for the CP group. In terms of relapse, 5-year incidence was 30% (95% confidence interval, 14-46%) for the AP group versus 15% (95% confidence interval, 11-19%) for the CP group (P=0.02). Results were confirmed in multivariable analysis and propensity score matching. Increase in circulating blasts was associated with increased risk for relapse, showing strongest increase in risk for ≥10% blasts. In conclusion, reduced intensity transplantation showed excellent survival but higher relapse for AP myelofibrosis.
PICO Summary
Population
People with primary or secondary myelofibrosis in four centres in France, Germany and USA (n=349)
Intervention
Reduced intensity conditioning and allogeneic transplantation in accelerated phase (AP, n=35)
Comparison
Reduced intensity conditioning and allogeneic transplantation in chronic phase (CP, n=314)
Outcome
After a median follow-up of 5.9 years, estimated 5-year overall survival was 65% in the AP group (95% confidence interval, 49-81%) versus 64% (95% CI, 59-69%) for the CP group, and median overall survival was not reached. In terms of relapse-free survival, estimated 5-year outcome for the AP group was 49% (95% CI, 32-67%) versus 55% (95% CI, 50-61%) for the CP group. Estimated 5-year non-relapse mortality was 20% (95% CI, 8-33%) for the AP group versus 30% (95% CI, 24-35%) for the CP group. In terms of relapse, 5-year incidence was 30% (95% CI, 14-46%) for the AP group versus 15% (95% CI, 11-19%) for the CP group. Results were confirmed in multivariable analysis and propensity score matching. Increase in circulating blasts was associated with increased risk for relapse, showing strongest increase in risk for ≥10% blasts.
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Reduced-intensity conditioning versus myeloablative conditioning allogeneic stem cell transplantation for patients with myelofibrosis
Kim, D. H., Seo, J., Shin, D. Y., Koh, Y., Hong, J., Kim, I., Yoon, S. S., Byun, J. M.
Blood research. 2022
Abstract
BACKGROUND Allogeneic hematopoietic stem cell transplantation (alloSCT) is the sole curative option for myelofibrosis (MF). However, it is unknown as to which of the two, myeloablative conditioning (MAC) or reduced-intensity conditioning (RIC), is a better preconditioning regimen. METHODS Twenty-five patients with MF were treated with alloSCT, 12 of whom underwent RIC. Baseline characteristics, response to alloSCT, adverse events, including graft-versus-host disease (GVHD), and survival outcomes were reviewed. RESULTS There was no difference in the neutrophil engraftment rate and time to engraftment between MAC vs. RIC. The time to platelet engraftment was significantly longer in the MAC group (median, 112.8 vs. 28.8 days for MAC vs. RIC, respectively, P=0.049). RIC was more advantageous in terms of achieving complete chimerism (38.5% vs. 83.3%, P=0.041). The incidence of acute GVHD was 84.6% (11 of 13) and 58.3% (7 of 12) in the MAC and RIC groups, respectively. The cumulative incidence of grade III-IV acute GVHD was significantly higher in the MAC group than in the RIC group (P=0.03). No significant differences were observed in progression-free and overall survival. The 17-month probability of progression-free survival was 38.4% [95% confidence interval (CI), 19.3-76.5] vs. 47.6% (95% CI, 25.7-88.2) (P=0.21), and that of overall survival was 53.8% (95% CI, 32.5-89.1) vs. 48.6% (95% CI, 26.8-88.3) (P=0.85) for MAC vs. RIC, respectively. CONCLUSION RIC offers a significant advantage over MAC, even in younger patients with MF undergoing alloSCT, in terms of cell engraftment, rate of complete chimerism achievement, and incidence of acute GVHD.