Age-Stratified Conditioning Regimen Efficacy for MDS Haplo-HSCT

Prospective Cohort Study of Age-Stratified Busulfan-Based Conditioning Regimens in Adult Patients With Myelodysplastic Syndrome Receiving Haploidentical Hematopoietic Stem Cell Transplantation

This study plan aims to enroll adult patients diagnosed with myelodysplastic syndrome (MDS) who are scheduled to receive T-cell-replete haploidentical hematopoietic stem cell transplantation. After obtaining written informed consent, participants will receive either reduced-toxicity Bu/Flu/Cy/ATG conditioning regimen (for patients aged ≥55 years) or standard myeloablative modified Bu/Cy+ATG conditioning regimen (for patients aged <55 years) followed by unified post-transplant immunosuppression and supportive care. The objective is to prospectively characterize the 1-year transplant-related mortality and comprehensively evaluate hematopoietic engraftment, graft-versus-host disease, infection, relapse, survival outcomes and conditioning-related organ toxicity among all enrolled patients undergoing haploidentical transplantation.

Study Overview

• Status: Not yet recruiting
• Conditions: Myelodysplastic Syndromes
• Intervention / Treatment: Drug: RTC conditioning regimen and Modified Bu/Cy conditioning regimen

• Study Type: Interventional
• Enrollment (Estimated): 120
• Phase: Phase 2

Contacts and Locations

• Study Contact: Name: Yu Wang; Phone Number: 8610-8832-6005; Email: ywyw3172@sina.com

Study Locations

• China
  • Beijing, China
    • Peking University People's Hospital, Beijing Lu Daopei Hematology Hospital, Hebei Yanda Lu Daopei Hospital, Nanfang Hospital, Southern Medical University
    • Contact: Xiaojun Huang; Phone Number: 8610-8832-6005; Email: huangxiaojun@bjmu.edu.cn

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Patients who had low- and intermediate-risk MDS without ISD nor URD receiving haploidentical hematopoietic stem cell transplantation

Exclusion Criteria:

• Patients having ISD or URD; patients having high-risk MDS; patients with active infection; patients with poor compliance; patients with organ failure

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm

Intervention / Treatment

Other: Age-Stratified Conditioning Regimen; MDS patients without identical sibling donor or unrelated donor would receive haplo-HSCT. Participants will receive either reduced-toxicity Bu/Flu/Cy/ATG conditioning regimen (for patients aged ≥55 years) or standard myeloablative modified Bu/Cy+ATG conditioning regimen (for patients aged <55 years) followed by unified post-transplant immunosuppression and supportive care.

Drug: RTC conditioning regimen and Modified Bu/Cy conditioning regimen; RTC preconditioning regimen consisted of cytarabine (2g/m2/day, days -10 to -9), busulfan (3.2 mg/kg/day on days -8 to -6), cyclophosphamide (1.0 g/m2/day, days -5 to -4), fludarabine (30 mg/m2/day, days -6 to -2), semustine (250 mg/m2, day-3), and rabbit antithymocyte globulin (thymoglobulin, 2.5 mg/kg/d, days -5 to -2; Sanofi, France). Bu/Cy preconditioning regimen consisted of tandard institutional myeloablative busulfan + cyclophosphamide + rabbit ATG regimen per department routine dosing guidelines.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
transplant-related mortality (TRM)	Death without disease progression or relapse	Participants will be followed for an expected average of 1 years

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Hematopoietic engraftment	Neutrophil engraftment is defined as the first day of sustained absolute neutrophil count (ANC) ≥0.5×10⁹/L for 3 consecutive days; platelet engraftment is defined as the first day of sustained platelet count (PLT) ≥20×10⁹/L without transfusion support for 7 consecutive days. Cumulative incidence of neutrophil engraftment at Day 30 and platelet engraftment at Day 90 will be calculated.	Day 30 and Day 90 post-transplantation
Cumulative incidence of graft-versus-host disease (GVHD)	Cumulative incidence of Grade II-IV and Grade III-IV acute GVHD at Day 100, as well as chronic GVHD and moderate-severe chronic GVHD within 3 years after transplantation, graded per Seattle criteria.	Day 100 and 3 years after transplantation
Cumulative incidence of CMV and EBV reactivation	Defined as any detectable CMV or EBV viral load elevation requiring clinical intervention within 1 year after transplantation.	1 year after transplantation
Cumulative incidence of hematologic relapse	Defined as bone marrow blast recurrence or extramedullary disease relapse within 1 year after transplantation.	1 year after transplantation
Disease-free survival (DFS)	Defined as the time from transplantation until hematologic relapse or death from any cause.	1 year after transplantation
Overall survival（OS）	Defined as the time from treatment until death from any cause or the last follow-up.	1 year after transplantation
Conditioning-related organ toxicities	Incidence of grade 1-4 cardiac, renal, hepatic, gastrointestinal and oral mucosal toxicities from conditioning initiation to Day +30 post-transplantation, with separate analysis of Grade 3-4 severe organ injury, hepatic veno-occlusive disease (VOD), and conditioning-related death, graded per WHO organ toxicity scale.	From conditioning start to Day 30 post-transplantation

Collaborators and Investigators

• Sponsor: Peking University People's Hospital
• Investigators: Principal Investigator: Xiao-Jun Huang, Peking University Institute of Hematology

Study record dates

Study Major Dates

• Study Start (Estimated): July 15, 2026
• Primary Completion (Estimated): December 31, 2027
• Study Completion (Estimated): June 30, 2028

Study Registration Dates

• First Submitted: June 24, 2026
• First Submitted That Met QC Criteria: June 24, 2026
• First Posted (Actual): June 30, 2026

Study Record Updates

• Last Update Posted (Actual): June 30, 2026
• Last Update Submitted That Met QC Criteria: June 24, 2026
• Last Verified: June 1, 2026

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Hematologic Diseases; Bone Marrow Diseases; Hemic and Lymphatic Diseases; Myelodysplastic Syndromes
• Other Study ID Numbers: RTC Haplo-MDS

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No