Blinatumomab Intensification for MRD-Negative Acute B-Cell Lymphoblastic Leukemia Before Allogeneic Hematopoietic Stem Cell Transplantation

First Affiliated Hospital of Zhejiang University114 enrolled

Overview

This is a prospective, multicenter, randomized controlled trial designed to evaluate whether short-term blinatumomab intensification before allogeneic hematopoietic stem cell transplantation (allo-HSCT) can improve survival outcomes in adults with high-risk BCR::ABL1-negative B-cell acute lymphoblastic leukemia (B-ALL) who have achieved measurable residual disease (MRD) negativity. Blinatumomab, a CD19/CD3 bispecific T-cell engager, has shown promising efficacy in eradicating MRD and prolonging survival in B-ALL patients. In this study, eligible participants will be randomly assigned to receive either short-term blinatumomab consolidation prior to allo-HSCT or proceed directly to allo-HSCT. The primary endpoint is relapse-free survival (RFS). This study aims to optimize treatment strategies and improve long-term outcomes for patients with high-risk BCR::ABL1-negative B-ALL.

Study Type

INTERVENTIONAL

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

NONE

Enrollment

114

Conditions

Acute Lymphoblastic Leukemia, B-precursor

Interventions

Blinatumomab is administered starting approximately one month before allogeneic hematopoietic stem cell transplantation (allo-HSCT). For participants weighing ≥45 kg: 9 μg/day is administered on Days 1-3, followed by 28 μg/day on Days 4-14. For participants weighing \<45 kg: 5 μg/m²/day (based on body surface area) is administered on Days 1-3, followed by 15 μg/m²/day on Days 4-14. The total dose must not exceed the dosage used for participants ≥45 kg.

Eligibility

Sex: ALLMin age: 18 YearsMax age: 65 Years

Medical Language ↔ Plain English

Inclusion Criteria: 1\. Diagnosed with B-cell acute lymphoblastic leukemia (B-ALL) according to the 2022 WHO classification. 2\. Age between 18 and 65 years. 3. Meets the National Comprehensive Cancer Network (NCCN) criteria for high-risk B-ALL, based on clinical or cytogenetic/molecular features: 1. Clinical high-risk features (any of the following): 1. Age \> 35 years 2. Peripheral WBC count \> 30 × 10⁹/L 3. Cytogenetic/molecular high-risk features (any of the following): 2. Cytogenetic and molecular high-risk features (at least one of the following): 1. Hypodiploidy (\<44 chromosomes) 2. TP53 mutation 3. KMT2A rearrangement 4. MLL rearrangement 5. HLF rearrangement 6. ZNF384 rearrangement 7. MEF2D rearrangement 8. MYC rearrangement 9. BCR-ABL1-like (Ph-like) ALL, including: 10. JAK pathway rearrangements (CRLF2r, EPORr, JAK1/2/3r, TYK2r, SH2B3 mutation, IL7R mutation, JAK1/2/3 mutations) 11. ABL-class rearrangements (ABL1, ABL2, PDGFRA, PDGFRB, FGFR1) 12. Other kinase fusions (e.g., NTRK3r, FLT3r, LYNr, PTK2Br) 13. PAX5alt 14. t(9;22)(q34.1;q11.2); BCR-ABL1 with IKZF1 mutation and/or prior chronic myeloid leukemia (CML) 15. Intrachromosomal amplification of chromosome 21 (iAMP21) 16. IKZF1 alteration 17. Complex karyotype (≥5 chromosomal abnormalities) 4. CD19-positive by immunophenotyping. 5. BCR::ABL1-negative. 6. Achieved complete remission (CR) after induction therapy. 7. Measurable residual disease (MRD)-negative by flow cytometry (FCM). 8. Availability of a matched sibling donor, haploidentical related donor, or matched/unmatched unrelated donor. 9\. ECOG performance status score of 0-2. 10. Creatinine clearance ≥ 60 mL/min (by Cockcroft-Gault formula). 11. AST and ALT ≤ 3 × upper limit of normal (ULN); total bilirubin ≤ 2 × ULN. 12. Left ventricular ejection fraction (LVEF) ≥ 50% by echocardiography. 13. Expected survival \> 8 weeks. 14. Signed written informed consent, with ability to understand and comply with the study protocol. Exclusion Criteria: 1. Prior exposure to blinatumomab, chimeric antigen receptor (CAR) T-cell therapy, or anti-CD22 immunotoxins. 2. Clinically significant cardiovascular disease, including uncontrolled arrhythmia, uncontrolled hypertension, congestive heart failure, NYHA class III or IV heart disease, or myocardial infarction within 3 months prior to screening. 3. Other severe comorbidities that may limit participation in the trial (e.g., severe infection, renal failure). 4. Known HIV infection or uncontrolled severe viral hepatitis. 5. Pregnant or breastfeeding women.

Outcomes

Primary Outcomes

2-year Relapse-Free Survival (RFS)

Relapse-free survival is defined as the time from transplantation to either disease relapse or death from any cause, whichever occurs first. Patients who are alive and relapse-free at 2 years will be considered as having achieved 2-year RFS.

Time frame: 2 years after transplantation

Secondary Outcomes

Cumulative Incidence of Relapse (CIR)

Defined as the cumulative incidence of hematologic relapse, accounting for competing risks such as non-relapse mortality.

Time frame: Up to 2 years after transplantation

Non-Relapse Mortality (NRM)

Death from any cause without prior hematologic relapse.

Time frame: Up to 2 years after transplantation

Incidence of Hematologic and Non-Hematologic Adverse Events

Safety evaluation based on CTCAE v5.0 criteria, including treatment-related cytopenias, infections, neurotoxicity, and other adverse events.

Time frame: From first dose of study drug to 100 days post-transplant

Measurable Residual Disease (MRD) Status

MRD status assessed using multi-parameter flow cytometry or PCR prior to HSCT. Evaluated as MRD-negative or MRD-positive.

Time frame: From enrollment to up to 2 years after transplantation

2-year Overall Survival (OS)

Overall survival is defined as the time from HSCT to death from any cause. Patients alive at 2 years are considered to have achieved 2-year OS.