Conditioning Regimen of 5-Day Decitabine Administration for Allogeneic Stem Cell Transplantation in Patients with Myelodysplastic Syndrome and Myeloproliferative Neoplasms

Mega-dose decitabine conditioning and prophylactic donor lymphocyte infusion for patients with relapsed/refractory AML with active disease at the time of allogeneic haematopoietic cell transplantation: A multicenter prospective phase II study

Patients with relapsed/refractory acute myeloid leukaemia (R/R AML), especially those who failed in novel target agents are related to dismal survival. We developed a multi-institutional, single-arm, prospective phase II trial, to investigate intensified conditioning with 'Mega-Dose' decitabine (MegaDAC) following allogeneic haematopoietic cell transplantation (allo-HCT) for R/R AML. From 2019 to 2023, 70 heavily treated R/R AML patients in active disease were consecutively enrolled. Significantly, every patient (n = 18) harbouring specific mutations exhibited no response to their best available target agents (BATs). Moreover, 74.3% of the enrolled patients did not reach remission following venetoclax-based regimens. All patients underwent intravenous decitabine (400 mg/m2) along with busulfan and cyclophosphamide. Median follow-up was 26 months (8-65) after HCT. All engrafted patients achieved MRD negativity post-HCT, with a median 3.3-log reduction in recurrent genetic abnormalities. The regimen was well tolerated, without irreversible grades III-IV toxicity peri-engraftment. The estimated 2-year CIR was 29.6% (18.4%-41.7%) and the est-2-year NRM was 15.5% (7.8%-25.5%). The est-2-year LFS, OS, and GRFS were 55.0% (43.5%-69.4%), 58.6% (47.0%-73.0%), and 42.9% (31.9%-57.6%), respectively. Multivariate analysis showed that pre-HCT drug exposures had no significant impact on primary outcomes. MegaDAC is highlighted as an effective and safe option for R/R AML in the new era of targeted therapies.

Impact of platelet transfusion refractoriness in the first 30 days post-hematopoietic stem cell transplantation on outcomes of patients with myelodysplastic syndrome

Introduction

Currently, no study has determined whether platelet transfusion refractoriness (PTR) post-hematopoietic stem cell transplantation (HSCT) before engraftment in patients with myelodysplastic syndrome (MDS) would impacts clinical outcomes.

Methods

We performed a MDS-specific retrospective analysis to determine whether PTR in one-month post-HSCT in patients with MDS could influence outcomes.

Results and discussion

Among the 315 patients enrolled, 110 (34.9 %) had PTR from stem cell infusion to one-month post-HSCT. Baseline characteristics of the PTR and non-PTR groups were similar. We found that patients with PTR had a slower and lower rate of platelet engraftment by day 28, as well as a slower recovery of neutrophils. The median days of neutrophil and platelet engraftment were 14 days (9-23) and 17 days (8-28) in the PTR groups versus 13 days (9-23) and 15 days (7-28) in the non-PTR group (P<0.001). By day 28, 84 of 110 patients (76.4%) with PTR achieved platelet engraftment compared with 181 of 205 patients (88.3%) without PTR achieving platelet engraftment (P=0.007). In addition, patients in the PTR group received significantly more red blood cell (median, 17 units vs. 10 units, P<0.001) and platelet transfusions (median, 13 units vs. 7 units, P<0.001). However, the overall survival was similar between the two groups. PTR in one-month post-HSCT, haploidentical donor, and ferritin level>1041ng/ml (median level) were independent adverse factors of platelet engraftment.

Current challenges in conditioning regimens for MDS transplantation

Myelodysplastic syndrome (MDS) is a very heterogeneous clonal disorder. Patients with "higher-risk" MDS, defined by specific recurrent genetic abnormalities, have a poor prognosis because of a high risk of progression to secondary acute myeloid leukemia with low chemosensitivity. Allogeneic hematopoietic stem cell transplantation remains the only treatment that offers durable disease control because the donor immune system allows graft-versus-MDS effects. In terms of preparation steps before transplantation, targeting the malignant clone by increasing the conditioning regimen intensity is still a matter of intense debate. MDS is mainly diagnosed in older patients, and high toxicity related to common myeloablative conditioning regimens has been reported. Efforts to include new drugs in the conditioning regimen to achieve the best malignant clone control without increasing toxicity have been made over the past 20 years. We summarized these retrospective and prospective studies and evaluated the limitations of the available evidence to delineate the ideal conditioning regimen.

WT1 gene mutations impact post-transplant relapse in myelodysplastic syndrome with excess blasts 2 patients

Wilms tumor 1 (WT1) gene mutations are infrequent in myelodysplastic syndrome (MDS), but MDS with WT1 mutations (WT1mut) is considered high risk for acute myeloid leukemia (AML) transformation. The influence of WT1 mutations in patients with MDS after allogeneic hematopoietic stem cell transplantation (allo-HSCT) is unclear. We performed a retrospective analysis of 136 MDS with excess blasts 2 (MDS-EB2) patients with available WT1 status who underwent their first allo-HSCT between 2017 and 2022 in our center. There were 20 (20/136, 15%) cases in the WT1mut group and 116 (116/136, 85%) cases in the WT1 wild-type (WT1wt) group. WT1mut patients had a higher 2-year cumulative incidence of relapse (CIR) than WT1wt cases (26.2% vs. 9.4%, p = 0.037) after allo-HSCT. Multivariate analysis of relapse showed that WT1 mutations (HR, 6.0; p = 0.002), TP53 mutations (HR, 4.2; p = 0.021), and ≥ 5% blasts in bone marrow (BM) at transplantation (HR, 6.6; p = 0.004) were independent risk factors for relapse. Patients were stratified into three groups according to the risk factors. Two-year CIR differed significantly in high-, intermediate-, and low-risk groups (31.8%, 11.6%, and 0%, respectively). Hence, WT1 mutations may be related to post-transplant relapse in patients with MDS-EB2, which warrants further study.

Decitabine-containing conditioning improved outcomes for children with higher-risk myelodysplastic syndrome undergoing allogeneic hematopoietic stem cell transplantation

Myelodysplastic syndrome (MDS) is a rare clonal hematopoietic disorder in children. The risk stratification system and treatment strategy for adults are unfit for children. The role of hypomethylating agents (HMAs) in higher-risk childhood MDS has not been identified. This study aimed to investigate the outcomes of hematopoietic stem cell transplantation (HSCT) in children with higher-risk MDS at one single center. A retrospective study was conducted in children with higher-risk MDS undergoing HSCT between September 2019 and March 2023 at Blood Diseases Hospital CAMS. The clinical characteristics and transplantation information were reviewed and analyzed. A total of 27 patients were analyzed, including 11 with MDS with excess blasts (MDS-EB), 14 with MDS-EB in transformation (MDS-EBt) or acute myeloid leukemia with myelodysplasia-related changes (AML-MRC), and 2 with therapy-related MDS/AML (t-MDS/AML). Eight patients harbored monosomy 7. Before transplantation, induction therapy was administered to 25 patients, and 19 of them achieved bone marrow blasts <5% before HSCT. The stem cell source was unmanipulated-related bone marrow or peripheral blood stem cells for nineteen patients and unrelated cord blood for eight. All patients received decitabine-containing and Bu/Cy-based myeloablative conditioning; 26 patients achieved initial engraftment. The cumulative incidences of grade II-IV and grade III-IV acute graft-versus-host disease (GvHD) at 100 days were 65.4% and 42.3%, respectively. The incidence of cGvHD was 38.5%. The median follow-up was 26 (range 4-49) months after transplantation. By the end of follow-up, two patients died of complications and two died of disease progression. The probability of 3-year overall survival (OS) was 84.8% (95%CI, 71.1 to 98.5%). In summary, decitabine-containing myeloablative conditioning resulted in excellent outcomes for children with higher-risk MDS undergoing allogeneic HSCT.

Innovations in conditioning and post-transplant maintenance in AML: genomically informed revelations on the graft-versus-leukemia effect

Acute Myeloid Leukemia (AML) is the prototype of cancer genomics as it was the first published cancer genome. Large-scale next generation/massively parallel sequencing efforts have identified recurrent alterations that inform prognosis and have guided the development of targeted therapies. Despite changes in the frontline and relapsed standard of care stemming from the success of small molecules targeting FLT3, IDH1/2, and apoptotic pathways, allogeneic stem cell transplantation (alloHSCT) and the resulting graft-versus-leukemia (GVL) effect remains the only curative path for most patients. Advances in conditioning regimens, graft-vs-host disease prophylaxis, anti-infective agents, and supportive care have made this modality feasible, reducing transplant related mortality even among patients with advanced age or medical comorbidities. As such, relapse has emerged now as the most common cause of transplant failure. Relapse may occur after alloHSCT because residual disease clones persist after transplant, and develop immune escape from GVL, or such clones may proliferate rapidly early after alloHSCT, and outpace donor immune reconstitution, leading to relapse before any GVL effect could set in. To address this issue, genomically informed therapies are increasingly being incorporated into pre-transplant conditioning, or as post-transplant maintenance or pre-emptive therapy in the setting of mixed/falling donor chimerism or persistent detectable measurable residual disease (MRD). There is an urgent need to better understand how these emerging therapies modulate the two sides of the GVHD vs. GVL coin: 1) how molecularly or immunologically targeted therapies affect engraftment, GVHD potential, and function of the donor graft and 2) how these therapies affect the immunogenicity and sensitivity of leukemic clones to the GVL effect. By maximizing the synergistic action of molecularly targeted agents, immunomodulating agents, conventional chemotherapy, and the GVL effect, there is hope for improving outcomes for patients with this often-devastating disease.

Outcomes of CMML patients undergoing allo-HCT are significantly worse compared to MDS-a study of the CMWP of the EBMT

Although CMML since long has been separated from MDS, many studies continue to evaluate the outcomes of both diseases after hematopoietic cell transplantation (allo-HCT) together. Data evaluating outcomes of a large CMML cohort after allo-HCT compared to MDS are limited. We aim to compare outcomes of CMML to MDS patients who underwent allo-HCT between 2010 and 2018. Patients ≥18 years with CMML and MDS undergoing allo-HCT reported to the EBMT registry were analyzed. Progression to AML before allo-HCT was an exclusion criterion. Overall survival (OS), progression/relapse-free survival (PFS), relapse incidence (including progression) (REL), and non-relapse mortality (NRM) were evaluated in univariable and multivariable (MVA) Cox proportional hazard models including interaction terms between disease and confounders. In total, 10832 patients who underwent allo-HCT were included in the study, there were a total of 1466 CMML, and 9366 MDS. The median age at time of allo-HCT in CMML (median 60.5, IQR 54.3-65.2 years) was significantly higher than in the MDS cohort (median 58.8, IQR 50.2-64.5 years; p < .001). A significantly higher percentage of CMML patients were male (69.4%) compared to MDS (61.2%; p < .001). There were no clinically meaningful differences in the distribution of Karnofsky score, Sorror HCT-CI score at allo-HCT, and donor type, between the CMML and MDS patients. RIC platforms were utilized in 63.9% of CMML allo-HCT, and in 61.4% of MDS patients (p = .08). In univariable analyses, we found that OS, PFS, and REL were significantly worse in CMML when compared with MDS (all p < .0001), whereas no significant difference was observed in NRM (p = .77). In multivariable analyses, the HR comparing MDS versus CMML for OS was 0.81 (95% CI, 0.74-0.88, p < .001), PFS 0.76 (95% CI 0.70-0.82, p < .001), relapse 0.66 (95% CI 0.59-0.74, p < .001), and NRM 0.87 (95% CI 0.78-0.98, p = .02), respectively. The association between baseline variables and outcome was found to be similar in MDS and CMML (all interaction p > .05) except for a decreasing trend over time of the risk of relapse in CMML (HR allo-HCT per year later 0.94, 95% CI 0.90-0.98), whereas no such trend was observed in MDS (HR 1.00, 95% CI 0.98-1.02). The poor outcome observed for CMML could be related to variables not measured in this study or to factors inherent to the disease itself. This study demonstrates that outcomes of CMML patients after allo-HCT are significantly worse compared to MDS. The results of this study may contribute to future recommendations for allo-HCT in CMML patients.

Hematopoietic Stem Cell Transplantation in the Management of Myelodysplastic Syndrome: A Retrospective, Current, and Future Perspective

Myelodysplastic syndrome (MDS) is a clonal disorder that affects hematopoietic stem cells (HSCs), primarily occurring in the elderly population. Lower-risk MDS is characterized by a decrease in blood cells, whereas higher-risk MDS is associated with an increased risk of transformation to acute myeloid leukemia (AML). Currently, the treatment of MDS is still unsatisfactory, although demethylating agents, azacitidine (AZA), and decitabine (Dec) have been successfully used to treat MDS and improve survival rates. However, hematopoietic stem cell transplantation (HSCT) remains the only curative treatment for MDS patients, effectively increasing patient survival and quality of life. Nevertheless, treatment-related toxicity, graft-versus-host disease, infectious complications, and relapse are still major post-transplant issues. In this review, through a retrospective analysis of past and present HSCT for the treatment of MDS, we provide insights for the future.

Efficacy of venetoclax combined with decitabine conditioning regimen for allogeneic hematopoietic stem cell transplantation in high-risk and elderly patients with myeloid neoplasms

This prospective clinical investigation focused on the addition of venetoclax and decitabine to myeloablative conditioning regimens, targeting high-risk and elderly individuals undergoing allogeneic hematopoietic stem cell transplantation. In total, 19 patients were enrolled in the trial between December 2021 and February 2023, and their progress was monitored for a median follow-up period of 258 days, ranging from 35 to 544 days. In the initial regimen (n=11), venetoclax was administered at a dosage of 400 mg per day from day -14 to day -1, while in the modified regimen (n=8), it was administered from day -14 to day -5. Decitabine was orally administered at a dosage of 20mg/m2/day from day -7 to day -3. Grade 3/4 adverse events observed included hematological events, hypertension, infections, allergy, and increased amylase. In the entire cohort, the overall survival (OS) and relapse-free survival (RFS) rates at 6 months were 63% (95% CI, 45-89) and 63% (95% CI, 45-89), respectively. The non-relapse mortality (NRM) rate at 6 months was 37% (95% CI, 16-58), while the cumulative incidence of relapse (CIR) was 0. However, the incidence of grade II-IV acute graft-versus-host disease (aGVHD) and grade III-IV aGVHD within 100 days was found to be 31% (95% CI, 12-53) and 26% (95% CI, 9-47), respectively. These rates indicate a relatively high occurrence, making it less suitable to administer the regimen to elderly patients. Therefore, further high-quality studies are required to enhance the conditioning regimen specifically for high-risk and elderly patients diagnosed with myeloid neoplasms. Clinical trial registration: ChiCTR2100050272.

Low-dose decitabine-intensified modified conditioning regimen alleviates aGVHD in AML/MDS patients treated with allogeneic hematopoietic stem cell transplantation

Background

The widespread adoption of Allogeneic Hematopoietic Stem Cell Transplantation (Allo-HSCT) has significantly improved the survival rates of patients with hematological malignancies. However, Graft-Versus-Host Disease (GVHD) remains a formidable complication, threatening patient prognosis. Recent research has indicated that decitabine (DAC), known for its hypomethylating properties may also exhibit immune-regulatory capabilities and a potential for reducing GVHD incidence and enhancing survival.

Methods

We retrospectively reviewed data from AML/MDS patients who underwent Allo-HSCT at our center from January 2010 to January 2023. From a total of 251 patients with complete data, we employed propensity score matching (PSM) to create 100 matched pairs (200 patients) for comprehensive trial analysis. Patients receiving low-dose DAC-containing regimen were matched with those who did not receive DAC.

Results

Patients in the DAC group exhibited a significantly lower incidence of grade II-IV acute GVHD (aGVHD) compared to non-DAC group (21% vs. 38%, P=0.013). Univariable and multivariable logistic regression analysis demonstrated DAC intervention as a protective factor against grade II-IV aGVHD (P=0.017, OR=0.47, 95% CI 0.23-0.81; P=0.018, OR=0.46, 95% CI 0.24-0.87). Multivariate competing risk regression further supported administration of decitabine as a protective factor against grade II-IV aGVHD (P=0.038, SHR=0.53, 95%CI 0.29-0.97). There was no significant difference between both groups concerning chronic GVHD, infection, disease relapse, overall survival, disease-free survival and GVHD free, relapse free survival. In MRD negative or intermediate risk subgroup, the grade II-IV aGVHD ameliorating effect of DAC was confirmed as well.

Conclusion

Low-dose DAC-intensified modified conditioning regimen could improve prognosis in AML/MDS Patients treated with allogeneic hematopoietic stem cell transplantation.

The outcome of acute leukemia patients with SET-NUP214 fusion after allogeneic stem cell transplantation

SET-NUP214 fusion gene, also known as TAF-1-CAN and SET-CAN, is observed in acute myeloid leukemia (AML) and T-cell lymphoblastic leukemia (T-ALL). SET-NUP214 fusion in T-cell lymphoblastic leukemia is associated with chemotherapy resistance, but the prognosis of patients with AML with SET-NUP214 has rarely been reported. In the present study, we retrospectively analyzed all patients with acute leukemia including AML and T-ALL patients with SET-NUP214 fusion who underwent allogeneic stem cell transplantation (alloHSCT) in our center from July 2017 to November 2022. Of the total 11 patients, 5 patients were diagnosed with AML and 6 patients were diagnosed with T-ALL de novo. All patients received myeloablative regimens in CR1, and there were three (60%) AML patients who relapsed post-alloHSCT and three T-ALL (50%) patients who relapsed post-alloHSCT. Only one patient with AML who relapsed post-alloHSCT responded to subsequent chemotherapy plus donor lymphocyte infusion and survived the last follow-up. The estimated 1-year overall survival and 3-year overall survival for all these 11 patients were 69.3% and 38.5%, respectively. The estimated 1-year leukemia-free survival and 3-year leukemia-free survival for all patients were 69.3% and 38.5%, respectively. The research shows a high incidence of relapse for patients with acute leukemia with the SET-NUP214 fusion gene, even after alloHSCT. More clinical trials or research with larger samples are urgently needed for this group of patients.

Cladribine- and decitabine-containing conditioning regimen has a low post-transplant relapse rate in patients with relapsed or refractory acute myeloid leukemia and high-risk myelodysplastic syndrome

To reduce the risk of relapse after allogeneic hematopoietic stem cell transplantation (allo-HSCT), there have been continuing efforts to optimize the conditioning regimens. Our study aimed to analyze the risk factors associated with the relapse of relapsed/refractory (R/R), high-risk acute myeloid leukemia (AML) and high-risk myelodysplastic syndrome (MDS) post-transplant and the efficacy of a new conditioning regimen involving decitabine and cladribine. Clinical data of 125 patients with R/R AML, high-risk AML and high-risk MDS who underwent allo-HSCT were collected. In addition, 35 patients with R/R AML, high-risk AML and high-risk MDS received treatment with a new conditioning regimen including decitabine and cladribine. Cox regression analysis was used to identify risk factors associated with OS, RFS and relapse. Among 125 patients who underwent allo-HSCT, CR before allo-HSCT and matched sibling donors were independent protective factors for OS. DNMT3A abnormality was an independent risk factor for both relapse and RFS. Among 35 patients who received a new conditioning regimen containing decitabine and cladribine, only six patients relapsed and 1-year cumulative incidence of relapse was 11.7%. Moreover, this new regimen showed efficient MRD clearance early after allo-HSCT. The combined decitabine- and cladribine-based conditioning regimen showed a low relapse rate and a high survival without an increased incidence of GVHD or adverse effects and thus has potential for use in allo-HSCT for R/R AML, high-risk AML and high-risk MDS.

A 7-Day Decitabine-Included Conditioning Regimen Accelerated Donor Hematopoietic Engraftment while Reduced the Occurrence of Mucositis without Interfering with Prognosis

INTRODUCTION

Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is the standard and curative treatment strategy for patients with hematologic malignancies. Recently, decitabine-included regimens have been investigated by several studies including ours, which may prevent relapse of primary malignant diseases.

METHODS

This study was to retrospectively evaluate a 7-day decitabine-included regimen with reduced dose of idarubicin for patients with hematologic malignancies who underwent allo-HSCT.

RESULTS

A total of 84 patients were enrolled, including 24 cases in 7-day and 60 cases in 5-day decitabine groups, respectively. Patients conditioned with 7-day decitabine regimen showed accelerated neutrophil (12.05 ± 1.97 vs. 13.86 ± 3.15; u = 9.309, p < 0.001) and platelet (16.32 ± 6.27 vs. 21.37 ± 8.57; u = 8.887, p < 0.001) engraftment compared with those treated with 5-day decitabine regimen. Patients in the 7-day decitabine group showed a significantly lower incidence rate of total (50.00% [12/24] versus 78.33% [47/60]; χ2 = 6.583, p = 0.010) and grade III or above (4.17% [1/24] vs. 31.67% [19/60]; χ2 = 7.147, p = 0.008) oral mucositis compared to those in the 5-day decitabine group. However, the occurrence of other major complications post-allo-HSCT and outcomes of patients in these two groups were comparable.

CONCLUSION

These results demonstrate that this 7-day decitabine-contained new conditioning regimen seems to be feasible and safe for patients with myeloid neoplasms who receive allo-HSCT, and a large-scale prospective study is needed to confirm the findings of this study.

The effect of granulocyte-colony stimulating factor, decitabine, and busulfan-cyclophosphamide versus busulfan-cyclophosphamide conditioning on relapse in patients with myelodysplastic syndrome or secondary acute myeloid leukaemia evolving from myelodysplastic syndrome undergoing allogeneic haematopoietic stem-cell transplantation: an open-label, multicentre, randomised, phase 3 trial

BACKGROUND

Relapse remains high in patients with myelodysplastic syndrome-refractory anaemia with excess blasts (RAEB) or secondary acute myeloid leukaemia evolving from myelodysplastic syndrome undergoing allogeneic haematopoietic stem-cell transplantation (HSCT). We aimed to investigate whether granulocyte-colony stimulating factor (G-CSF) and decitabine plus busulfan-cyclophosphamide conditioning reduced relapse compared with busulfan-cyclophosphamide in this population.

METHODS

We did an open-label, randomised, phase 3 trial at six hospitals in China. Eligible patients (aged 14-65 years) had myelodysplastic syndrome-RAEB or secondary acute myeloid leukaemia evolving from myelodysplastic syndrome, and an Eastern Cooperative Oncology Group performance status of 0-2 and HSCT comorbidity index of 0-2. Patients were randomly assigned (1:1) to receive G-CSF, decitabine, and busulfan-cyclophosphamide conditioning or busulfan-cyclophosphamide conditioning. Randomisation was done with permuted blocks (block size four) with no stratification and was implemented through an interactive web-based response system, which was independent of study site staff and investigators. G-CSF, decitabine, and busulfan-cyclophosphamide conditioning comprised G-CSF 5 μg/kg daily subcutaneously (days -17 to -10), decitabine 20 mg/m² daily intravenously (days -14 to -10), busulfan 3·2 mg/kg daily intravenously (days -7 to -4), and cyclophosphamide 60 mg/kg daily intravenously (days -3 and -2). Busulfan-cyclophosphamide conditioning comprised the same dose and duration of busulfan and cyclophosphamide. The primary endpoint was 2 year cumulative incidence of relapse. All efficacy and safety endpoints were assessed in the intention-to-treat population. This trial is registered with ClinicalTrials.gov, NCT02744742; the trial is complete.

FINDINGS

Between April 18, 2016, and Sept 30, 2019, 297 patients were screened for eligibility, 202 of whom were randomly assigned to G-CSF, decitabine, and busulfan-cyclophosphamide (n=101) or busulfan-cyclophosphamide (n=101) conditioning. 123 (61%) participants were male and 79 (31%) were female. Median follow-up was 32·4 months (IQR 10·0-43·0). The 2-year cumulative incidence of relapse was 10·9% (95% CI 5·8-17·9) in the G-CSF, decitabine, and busulfan-cyclophosphamide group and 24·8% (16·8-33·5) in the busulfan-cyclophosphamide group (hazard ratio 0·39 [95% CI 0·19-0·79]; p=0·011). Within 100 days after transplantation, the most common grade 3-4 adverse events in the G-CSF, decitabine, and busulfan-cyclophosphamide group and the busulfan-cyclophosphamide group were infections (34 [34%] and 32 [32%]), acute graft-versus-host disease (30 [30%] and 30 [30%]), and gastrointestinal toxicity (28 [28%] and 29 [29%]). 11 (11%) patients in the G-CSF, decitabine, and busulfan-cyclophosphamide group and 13 (13%) in the busulfan-cyclophosphamide group died of adverse events. There were no treatment related deaths.

INTERPRETATION

Our results suggest that G-CSF, decitabine, and busulfan-cyclophosphamide conditioning is a better choice than busulfan-cyclophosphamide conditioning for patients with myelodysplastic syndrome-RAEB or secondary acute myeloid leukaemia evolving from myelodysplastic syndrome undergoing allogeneic HSCT. This conditioning could be a suitable therapuetic option for this patient population.

FUNDING

None.

TRANSLATION

For the Chinese translation of the abstract see Supplementary Materials section.

Long-term survivors demonstrate superior quality of life after haploidentical stem cell transplantation to matched sibling donor transplantation

BACKGROUND

It has been well-documented that haplo-identical hematopoietic stem cell transplantation (HID-HSCT) can provide outcomes comparable to conventional matched sibling donor (MSD) HSCT, however, little is known about the effects on quality of life (QoL) in long-term survivors. This study is to investigate the differences in longitudinal performance of QoL between HID and MSD HSCT using a comprehensive assessment system.

METHODS

This prospective study enrolled consecutive patients who had received allogenic-HSCT (allo-HSCT) between January 2018 and December 2019 in our center. All patients were informed to complete QoL questionnaires including the Mos 36-Item Short-Form Health Survey (SF-36) and the Functional Assessment of Cancer Therapy Bone Marrow Transplant (FACT-BMT, version 4), using an online applet, before transplantation and at scheduled time points after transplantation. The linear mixed-effects model was used to analyze the variation trend of different dimensions of both SF-36 and FACT-BMT with different follow-up times.

RESULTS

Of the 425 participants, recipients of HID and MSD who survived more than 1 year (n = 230) were included in the final analysis of QoL (median age [range]: 36, [15, 66]). The 3 year overall survival (OS) of HID and MSD was 82.42% and 86.46%, respectively. QoL was assessed using both SF-36 and FACT-BMT and there was longitudinal recovery with clinical significance in the cohort. Compared to MSD-HSCT patients, HID-HSCT recipients demonstrated superior QoL performance in some subscales describing physical and mental wellness. Specifically, the difference in physical performance is more remarkable using FACT-BMT whereas that in mental wellness is more significant using SF36. In the subsequent stratified analysis, patients with a history of aGVHD or CMV reactivation demonstrated inferior QoL.

CONCLUSIONS

Long-term survivors of HID HSCT achieved better QoL in some sub-scales compared to MSD HSCT. In addition, SF-36 and FACT-BMT demonstrated different performance thus combination of both improved capacity of the evaluation system.

Efficacy of decitabine combined with allogeneic hematopoietic stem cell transplantation in the treatment of recurrent and refractory acute myeloid leukemia (AML): A systematic review and meta-analysis

BACKGROUND

This analysis aimed to assess the effect of decitabine combined with allogeneic hematopoietic stem cell transplantation (allo-HSCT) in treating recurrent and refractory acute myeloid leukemia.

METHOD

The present analysis was carried out according to the principles of Preferred Reporting Items for Systematic Reviews and Meta-Analyses guideline statement. Web of Science, Embase, PubMed, The Cochrane Library, CNKI, VIP, and WanFang Data databases were searched for trials published from their corresponding inception to September 13, 2021. Retrospective research or published randomized controlled trials in Chinese or English were ruled out. The methodological quality of the included studies was assessed using the Physiotherapy Evidence Database scale. Mean differences with 95% confidence intervals were used to analyze continuous data. The I2 test was used to determine heterogeneity, and the meta-analysis was conducted using Revman 5.4.

RESULTS

Eight studies including 795 participants in total were identified. Decitabine and allo-HSCT showed significant reductions in recurrence after transplantation (odds ratio [OR] = 0.29, 95% confidence interval [CI] (0.17, 0.50), P < .00001), leukemia-free survival (OR = 2.17, 95% CI (1.47, 3.21), P < .0001), graft related death (OR = 0.50, 95% CI (0.25, 0.98), P = .04), and significant improvements in complete remission (OR = 0.39, 95% CI = 0.23-0.68, P = .0007) and partial remission (OR = 0.46, 95%CI = 0.27-0.78, P = .004). The median follow-up time, acute graft-versus-host disease, and no remission had no significant difference between treatment and control groups (the median follow-up time: OR = -1.76, 95% CI (-6.28, 2.76), P = .45; acute graft-versus-host disease: OR = 0.72, 95% CI (0.50, 1.03), P = .08; no remission: OR = 3.19, 95%CI = 2.06-4.94, P = .05). Overall, the magnitude of the effect was found to be in the small to moderate range.

CONCLUSION

Decitabine combined with allo-HSCT can obtain lower recurrence risk and longer disease-free survival time, and improve the prognosis of patients. The safety is relatively stable. Due to the varying quality level of the included studies, the validation of multiple high-quality studies still needs improvement.

Allogeneic haematopoietic stem cell transplantation with decitabine-containing preconditioning regimen in TP53-mutant myelodysplastic syndromes: A case study

Myelodysplastic syndrome (MDS) with TP53 mutations has a poor prognosis after transplantation, and novel therapeutic means are urgently needed. Decitabine (Dec) monotherapy has demonstrated improved overall response rates in MDS and acute myeloid leukaemia, although these responses were not durable. This study aimed to preliminary evaluate the efficacy of a Dec-containing allogeneic haematopoietic stem cell transplantation (allo-HSCT) preconditioning regimen in TP53-mutant MDS. Nine patients with TP53-mutant myelodysplastic syndromes received the decitabine-containing preconditioning regimen and subsequent myeloablative allo-HCT between April 2013 and September 2021 in different centres. At a median follow-up of 42 months (range, 5 to 61 months), the overall survival (OS) was 89% (8/9), progression-free survival (PFS) was 89% (8/9), and relapse incidence was 11.1%. The incidence of severe acute (grade III-IV) graft-versus-host disease (GVHD) was 22.2% (2/9) and that of chronic moderate-to-severe GVHD was 11.1% (1/9). The 1-year GVHD-free/relapse-free survival (GRFS) was 56% (5/9). In conclusion, we found real-world clinical data that supports the use of a Dec-containing preconditioning regimen before allo-HSCT for possible improved outcomes in TP53-mutant MDS patients; there is therefore an urgent call for an in-depth exploration of the involved mechanism to confirm these preliminary findings.

Low-Dose 5-Aza and DZnep Alleviate Acute Graft-Versus-Host Disease With Less Side Effects Through Altering T-Cell Differentiation

Objective

Previous studies showed that hypomethylating agents (HMAs) could alleviate acute graft-versus-host disease (aGvHD), but affect engraftment after allogeneic hematopoietic stem cell transplantation (allo-HSCT). The combination of two different HMAs in lower doses might overcome this problem. This study aimed to evaluate the treatment effect of the combination of two HMAs—azacitidine (5-Aza) and histone H3K27 methyltransferase inhibitor 3-deazaneplanocin (DZNep)—for the prophylaxis of aGvHD after allo-HSCT and to explore the possible mechanisms.

Methods

We first optimized the concentrations of individual and combinational 5-Aza and DZNep treatments to ensure no obvious toxicities on activated T cells by evaluating T-cell proliferation, viability, and differentiation. A mouse model of aGvHD was then established to assess the prophylactic efficacy of 5-Aza, DZNep, and their combination on aGvHD. The immunomodulatory effect on T cells and the hematopoietic reconstruction were assessed. Additionally, RNA sequencing (RNA-seq) was performed to identify the underlying molecular mechanisms.

Results

Compared with single treatments, the in vitro application of 5-Aza with DZNep could more powerfully reduce the production of T helper type 1 (Th1)/T cytotoxic type 1 (Tc1) cells and increase the production of regulatory T cells (Tregs). In an allo-HSCT mouse model, in vivo administration of 5-Aza with DZNep could enhance the prophylactic effect for aGvHD compared with single agents. The mechanism study demonstrated that the combination of 5-Aza and DZNep in vivo had an enhanced effect to inhibit the production of Th1/Tc1, increase the proportions of Th2/Tc2, and induce the differentiation of Tregs as in vitro. RNA-seq analysis revealed the cytokine and chemokine pathways as one mechanism for the alleviation of aGvHD with the combination of 5-Aza and DZNep.

Conclusion

The combination of 5-Aza and DZNep could enhance the prophylactic effect for aGvHD by influencing donor T-cell differentiation through affecting cytokine and chemokine pathways. This study shed light on the effectively prophylactic measure for aGvHD using different epigenetic agent combinations.

Comparative analysis of Decitabine intensified BUCY2 and BUCY2 conditioning regimen for high-risk MDS patients undergoing allogeneic hematopoietic stem cell transplantation

The optimal conditioning regimen for high-risk myelodysplastic syndrome (MDS) patients undergoing allogeneic hematopoietic stem cell transplantation (allo-HSCT) remains elusive. This study aimed to explore the anti-leukemic efficacy and toxicity of Decitabine (Dec, 20 mg/m²/day, day -11 to -7) intensified BUCY2 vs. traditional regimen in high-risk MDS population. We retrospectively evaluated 93 consecutive high-risk MDS patients undergoing allo-HSCT in our institution, comparing discrepancies in clinical characteristics and outcomes between cases using Dec-intensified BUCY2 (n = 52) and traditional BUCY2 regimen (n = 41). Three-year cumulative incidence of relapse after Dec-intensified BUCY2 conditioning was remarkably lower than that of patients using BUCY2 regimen (20.2% vs. 39.0%, p = 0.034). Overall survival and disease-free survival at 3 years for Dec-intensified BUCY2 group were 70.2% and 64.9%, respectively, which were significantly improved when compared with BUCY2 group (51.1% and 43.9%, p = 0.031 and p = 0.027). Furthermore, overall survival and disease-free survival for MDS cases receiving cytoreduction therapy were dramatically better than patients in non-cytoreduction group (p = 0.041, p = 0.047). In summary, the Dec-intensified conditioning regimen could be effective and feasible, providing prominent recurrence control with moderate toxicity for high-risk MDS patients. These patients might also benefit from pre-transplant cytoreductive therapeutic schedules. Larger randomized controlled trials are still needed to further confirm these conclusions.

Decitabine-Intensified Modified Busulfan/Cyclophosphamide Conditioning Regimen Improves Survival in Acute Myeloid Leukemia Patients Undergoing Related Donor Hematopoietic Stem Cell Transplantation: A Propensity Score Matched Analysis

To identify the benefit of decitabine (Dec)-intensified myeloablative conditioning on the outcomes of patients with acute myeloid leukemia (AML) after related donor hematopoietic stem cell transplantation (HSCT), we performed a retrospective matched-pair study from a pool of 156 patients to evaluate Dec [20 mg/m²/day intravenously (i.v.) on days -11 to -7]-intensified modified busulfan/cyclophosphamide (mBuCy) conditioning regimen vs. mBuCy regimen in 92 AML patients, with 46 patients in each cohort. The cumulative incidence of grade II-IV acute graft-versus-host disease (aGVHD) was lower in the Dec group (15.2% ± 0.3% vs. 32.6% ± 0.5%, P = 0.033). Compared with mBuCy group (15.5% ± 0.3%), a significantly higher proportion of limited chronic GVHD (cGVHD) in Dec group (35% ± 0.6%) was observed (P = 0.025). Dec-intensified mBuCy conditioning was associated with better 2-year overall survival (OS) and GVHD-free relapse-free survival (GRFS) (81% ± 6.2% vs. 59.4% ± 7.5%, P = 0.03; 58.7% ± 8.1% vs. 40.9% ± 7.3%, P = 0.042; respectively). Our results also elucidated that the Dec group had better 2-year OS and lower 2-year cumulative incidence of relapse (CIR) in patients acquiring haploidentical HSCT than that of the mBuCy group (84.8% ± 7.1% vs. 58.2% ± 10.3%, P = 0.047; 17.9% ± 0.8% vs. 40.0% ± 1.0%, P = 0.036; respectively), which did not increase the treatment-related mortality and regimen-associated toxicities. Dec-intensified myeloablative regimen and high-risk stratification were the variables associated with OS, leukemia-free survival (LFS), and GRFS in multivariate analysis. In high-risk patients, no differences were found in CIR, OS, LFS, and GRFS between the two groups. These data indicated that Dec-intensified mBuCy conditioning regimen was associated with better survival than mBuCy regimen in AML patients, especially in patients undergoing haploidentical HSCT.

Efficacy of Recombinant Human Thrombopoietin for the Treatment of Secondary Failure of Platelet Recovery After Allogeneic HSCT

Secondary failure of platelet recovery (SFPR) is a life-threatening complication that may affect up to 20% of patients after allogeneic hematopoietic stem cell transplantation (HSCT). In this study, to evaluate the efficacy of recombinant human thrombopoietin (rhTPO), we retrospectively analyzed 29 patients who received continuous rhTPO for the treatment of SFPR. Overall response and complete response were observed in 24 (82.8%) patients and 10 (34.5%) patients, at a median time of 21.5 days (range, 3-41 days) and 39.5 days (range, 7-53 days) after initiation of rhTPO treatment, respectively. Among the responders, the probability of keeping overall response and complete response at 1 year after response was 77.3% and 80.0%, respectively. In multivariate analysis, higher CD34⁺ cells (≥3 × 10⁶/kg) infused during HSCT (HR: 7.22, 95% CI: 1.53-34.04, P = 0.01) and decreased ferritin after rhTPO treatment (HR: 6.16, 95% CI: 1.18-32.15, P = 0.03) were indicated to associate with complete response to rhTPO. Importantly, rhTPO was well tolerated in all patients without side effects urging withdrawal and clinical intervention. The results of this study suggest that rhTPO may be a safe and effective treatment for SFPR.

The consensus from The Chinese Society of Hematology on indications, conditioning regimens and donor selection for allogeneic hematopoietic stem cell transplantation: 2021 update

The consensus recommendations in 2018 from The Chinese Society of Hematology (CSH) on indications, conditioning regimens and donor selection for allogeneic hematopoietic stem cell transplantation (allo-HSCT) facilitated the standardization of clinical practices of allo-HSCT in China and progressive integration with the world. There have been new developments since the initial publication. To integrate recent developments and further improve the consensus, a panel of experts from the CSH recently updated the consensus recommendations, which are summarized as follows: (1) there is a new algorithm for selecting appropriate donors for allo-HSCT candidates. Haploidentical donors (HIDs) are the preferred donor choice over matched sibling donors (MSDs) for patients with high-risk leukemia or elderly patients with young offspring donors in experienced centers. This replaces the previous algorithm for donor selection, which favored MSDs over HIDs. (2) Patients with refractory/relapsed lymphoblastic malignancies are now encouraged to undergo salvage treatment with novel immunotherapies prior to HSCT. (3) The consensus has been updated to reflect additional evidence for the application of allo-HSCT in specific groups of patients with hematological malignancies (intermediate-risk acute myeloid leukemia (AML), favorable-risk AML with positive minimal residual disease, and standard-risk acute lymphoblastic leukemia). (4) The consensus has been updated to reflect additional evidence for the application of HSCT in patients with nonmalignant diseases, such as severe aplastic anemia and inherited diseases. (5) The consensus has been updated to reflect additional evidence for the administration of anti-thymocyte globulin, granulocyte colony-stimulating factors and post-transplantation cyclophosphamide in HID-HSCT.

A Retrospective Observation of Treatment Outcomes Using Decitabine-Combined Standard Conditioning Regimens Before Transplantation in Patients With Relapsed or Refractory Acute Myeloid Leukemia

Hypomethylating agents, decitabine (DAC) and azacitidine, can act as prophylactic and pre-emptive approaches after allogeneic hematopoietic stem cell transplantation (allo-HSCT) and a non-intensive bridging approach before allo-HSCT. However, they are rarely used as a part of conditioning regimens in patients with relapsed or refractory acute myeloid leukemia (AML). This retrospectively study included a total of 65 patients (median, 37; range, 13–63) with relapsed or refractory AML who were treated by allo-HSCT after myeloablative conditioning regimens without or with DAC (high-dose DAC schedule, 75 mg/m² on day −9 and 50 mg/m² on day −8; low-dose DAC schedule, 25 mg/m²/day on day −10 to −8). DAC exerted no impact on hematopoietic reconstitution. However, patients who were treated with the high-dose DAC schedule had significantly higher incidence of overall survival (OS, 50.0%) and leukemia-free survival (LFS, 35.0%), and lower incidence of relapse (41.1%) and grade II–IV acute graft versus host disease (aGVHD, 10.0%) at 3 years, when compared with those treated with standard conditioning regimens or with the low-dose DAC schedule. In conclusion, high-dose DAC combined with standard conditioning regimens before allo-HSCT is feasible and efficient and might improve outcomes of patients with relapsed or refractory AML, which provides a potential approach to treat these patients.

Pre-conditioning intervention in patients with relapsed or refractory acute lymphoblastic leukemia who underwent allogeneic hematopoietic cell transplantation: a KSGCT multicenter retrospective analysis

The efficacy and clinical significance of pre-conditioning intervention (PCI) before allogeneic hematopoietic cell transplantation (HCT) in patients with acute lymphoblastic leukemia (ALL) not in remission remain inconclusive. The purpose of this multicenter retrospective study was to clarify the clinical significance of PCI before HCT in patients with non-remission ALL. Patients with non-remission ALL who received HCT between 2005 and 2015 at 16 institutions were included. PCI was objectively defined and classified to three groups according to the intensity of PCI (no, intensive, or moderate). The study cohort consisted of 104 patients with a median age of 38 (range 17-68). A significant decrease of blast percentage in the peripheral blood (PB) was confirmed in both PCI groups, suggesting that PCIs were effective to stabilize the disease activity. The group with moderate PCI had higher nucleated cell count in the BM compared to the group with intensive PCI or the group without PCI. The overall survival (OS) rates of groups with intensive and no PCI showed comparable and significantly better compared to the group with moderate PCI (P = 0.009). Multivariate analysis demonstrated that the OS of moderate PCI group was significantly worse compared to that of intensive PCI group (HR = 2.43, 95% CI: 1.32-4.14, P = 0.004), while the OS of intensive PCI group was comparable to that of the group without PCI. These results suggest that the intensity of PCI rather than the response to PCI may contribute to improve the transplant outcome in patients with ALL not in remission.

Haematologic malignancies with unfavourable gene mutations benefit from donor lymphocyte infusion with/without decitabine for prophylaxis of relapse after allogeneic HSCT: A pilot study

Relapse is the main cause of treatment failure for leukaemia patients with unfavourable gene mutations who receive allogeneic haematopoietic stem cell transplantation (allo‐HSCT). There is no consensus on the indication of donor lymphocyte infusion (DLI) for prophylaxis of relapse after allo‐HSCT. To evaluate the tolerance and efficacy of prophylactic DLI in patients with unfavourable gene mutations such as FLT3‐ITD, TP53, ASXL1, DNMT3A or TET2, we performed a prospective, single‐arm study. Prophylactic use of decitabine followed by DLI was planned in patients with TP53 or epigenetic modifier gene mutations. The prophylaxis was planned in 46 recipients: it was administered in 28 patients and it was not administered in 18 patients due to contraindications. No DLI‐associated pancytopenia was observed. The cumulative incidences of grade II–IV and III–IV acute graft‐versus‐host disease (GVHD) at 100 days post‐DLI were 25.8% and 11.0%, respectively. The rates of chronic GVHD, non‐relapse mortality and relapse at 3 years post‐DLI were 21.6%, 25.0% and 26.1%, respectively. The 3‐year relapse‐free survival and overall survival (OS) rates were 48.9% and 48.2%, respectively. Acute GVHD (HR: 2.30, p = 0.016) and relapse (HR: 2.46, p = 0.003) after DLI were independently associated with inferior OS. Data in the current study showed the feasibility of prophylactic DLI with/without decitabine in the early stage after allo‐HSCT in patients with unfavourable gene mutations.

Decitabine induction with myeloablative conditioning and allogeneic hematopoietic stem cell transplantation in high-risk patients with myeloid malignancies is associated with a high rate of infectious complications

Patients with high-risk myelodysplastic syndrome or acute myeloid leukemia have an increased risk of death following allogeneic hematopoietic stem cell transplantation (allo-HSCT). Decitabine has minimal non-hematologic toxicity and proven efficacy in myeloid diseases, and post-transplant cyclophosphamide (PTCy) has reduced rates of graft-versus-host-disease (GVHD). We hypothesized that decitabine induction with allo-HSCT and PTCy would improve outcomes in a high-risk myeloid disease population. We performed a phase-II trial of decitabine at 20 mg/m² for 10 days followed by allo-HSCT using a myeloablative regimen of fludarabine, IV busulfan and 4 Gy total body irradiation with PTCy for GVHD prophylaxis. Twenty patients underwent decitabine induction and 17 patients proceeded to transplant per protocol. Median overall survival from decitabine induction was 210 days (95 % CI 122-not reached). All patients developed grade 4 neutropenia after decitabine, eleven patients (55 %) developed grade 3-4 infections, and 5 cases were fatal. There were 5/20 (25 %) long-term survivors with a median follow-up of 3.6 years. Decitabine induction followed by myeloablative allo-HSCT in a high-risk population was associated with a high risk of infection and mortality related to enhanced immunosuppression. Further exploration of decitabine conditioning on reduced intensity platforms and improved infectious prophylaxis and screening may better mitigate toxicity (ClinicalTrials.gov (NCT01707004)).