Dexamethasone, Intravenous Injection of Human Immunoglobulin, and Increased Infusion of Mononuclear Cells to Reduce Donor Specific Antibodies in Haploidentical Hematopoietic Stem Cell Transplantation

NCT07698080 | Not Yet Recruiting Phase 2

• 1 other identifier: KM-10
• Study Type: interventional
• Target: 60
• Locations: 0 countries
• Sites: N/A

Brief Summary

This study tests whether a combination of three treatments - dexamethasone (a steroid), intravenous immunoglobulin (IVIG, a protein that helps the immune system), and an extra dose of donor mononuclear cells - can safely lower harmful antibodies called donor-specific antibodies (DSA) in patients who need a stem cell transplant from a half-matched (haploidentical) family donor. In these transplants, DSA are antibodies made by the patient's own body that attack the donor's stem cells. If DSA levels are high, the transplant is more likely to fail - the donor cells may not "take" (engraft). Currently, there is no single, simple, and reliable way to reduce DSA, and many existing methods have drawbacks. Based on the investigators' earlier experience in 11 patients, this three-part approach seemed to work well. All patients successfully engrafted, and DSA levels dropped quickly. Now the study team want to confirm these results in a larger, prospective, multicenter study. The investigators plan to enroll 60 patients aged 18-65 with blood cancers or other blood disorders who need a haploidentical transplant, have DSA levels above 500 MFI (a measure of antibody strength), and have no other suitable donor available. Participants will receive:

• Dexamethasone (25 mg/m²) for 4 days before transplant,
• IVIG (1 g/kg) one day before transplant,
• Extra mononuclear cells on transplant day - the extra amount depends on how high their DSA level is (low, medium, or high). The main goal is to see how many patients have primary graft failure (when the donor cells never engraft). The study team will also measure how long it takes for blood counts to recover, rates of graft-versus-host disease, survival, and side effects. All participants will be followed for 1 year. This study will help the investigators find out whether this combination is a safe, simple, and effective way to improve transplant success for patients with DSA who have no other donor options.

Conditions

Leukemia; Lymphoma; Thalassemia; Aplastic Anemia; Myelodysplastic Syndromes

Outcome Measures

Primary Outcomes (1)

• Primary Graft Failure (PGF)

  Day +28 post-transplant

Secondary Outcomes (5)

• Neutrophil and Platelet Engraftment Time

  Up to 28 days post-transplant

• Dynamic Changes in Donor-Specific Antibody (DSA) MFI Levels

  Pre-transplant (day -14 to -1) through day +22 post-transplant

• Incidence of Acute and Chronic Graft-Versus-Host Disease

  Up to 1 year post-transplant

• Overall Survival and Disease-Free Survival

  Up to 1 year post-transplant

• Incidence of Adverse Events

  Up to 1 year post-transplant

Study Arms (1)

Triple Therapy to Reduce DSA in Haploidentical HSCT: A Prospective Multicenter Study

EXPERIMENTAL

Participants receive dexamethasone (25 mg/m² × 4 days) and intravenous immunoglobulin (1 g/kg) prior to haploidentical hematopoietic stem cell transplantation, plus an additional dose of donor mononuclear cells on transplant day. The additional dose is stratified by baseline DSA MFI level: ≤5000: +2±2×10⁸/kg; 5000-10000: +4±2×10⁸/kg; \>10000: +6±2×10⁸/kg.

Biological: Intravenous Immunoglobulin; Drug: Dexamethasone; Biological: Mononuclear Cells

Interventions

Intravenous Immunoglobulin BIOLOGICAL

1 g/kg intravenously on day -1 prior to transplant.

Triple Therapy to Reduce DSA in Haploidentical HSCT: A Prospective Multicenter Study

Dexamethasone DRUG

25 mg/m² intravenously for 4 days prior to transplant (days -4 to -1).

Triple Therapy to Reduce DSA in Haploidentical HSCT: A Prospective Multicenter Study

Mononuclear Cells BIOLOGICAL

Additional donor MNCs infused on day 0. Dose stratified by baseline DSA MFI level: ≤5000: +2±2×10⁸/kg; 5000-10000: +4±2×10⁸/kg; \>10000: +6±2×10⁸/kg.

Triple Therapy to Reduce DSA in Haploidentical HSCT: A Prospective Multicenter Study

Eligibility Criteria

• Age: 18 Years - 65 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Diagnosis of benign or malignant hematological diseases (including leukemia, lymphoma, thalassemia, aplastic anemia, myelodysplastic syndromes, etc.) confirmed by NCCN guidelines, and determined by the investigator to require allogeneic hematopoietic stem cell transplantation.
• Eastern Cooperative Oncology Group (ECOG) performance status ≤ 3.
• Donor-specific antibody (DSA) mean fluorescence intensity (MFI) \> 500.
• Age between 18 and 65 years (age limits are also captured separately in the eligibility module).
• Body weight between 40 kg and 100 kg.
• No other suitable donor available (i.e., no DSA-negative related donor or unrelated donor).

You may not qualify if:

• Patients unsuitable for transplantation or without willingness to undergo transplantation, or diagnosed with non-hematological diseases.
• Estimated life expectancy \< 1 month.
• Known allergy to any drug or intervention used in the study regimen.
• Pregnancy, lactation, active severe infection, or severe major organ dysfunction.
• Severe psychiatric or neurological disorders that may affect the ability to provide informed consent and/or to report adverse events or comply with observation.
• Refusal or inability to sign the informed consent form.

Sponsors & Collaborators

• Hematology department of the 920th hospital: lead

MeSH Terms

Conditions

Leukemia; Lymphoma; Thalassemia; Anemia, Aplastic; Myelodysplastic Syndromes

Interventions

Immunoglobulins, Intravenous; Dexamethasone

Condition Hierarchy (Ancestors)

Neoplasms by Histologic Type; Neoplasms; Hematologic Diseases; Hemic and Lymphatic Diseases; Lymphoproliferative Disorders; Lymphatic Diseases; Immunoproliferative Disorders; Immune System Diseases; Anemia, Hemolytic, Congenital; Anemia, Hemolytic; Anemia; Hemoglobinopathies; Genetic Diseases, Inborn; Congenital, Hereditary, and Neonatal Diseases and Abnormalities; Bone Marrow Failure Disorders; Bone Marrow Diseases

Intervention Hierarchy (Ancestors)

Immunoglobulin G; Immunoglobulin Isotypes; Antibodies; Immunoglobulins; Immunoproteins; Blood Proteins; Proteins; Amino Acids, Peptides, and Proteins; Serum Globulins; Globulins; Pregnadienetriols; Pregnadienes; Pregnanes; Steroids; Fused-Ring Compounds; Polycyclic Compounds; Steroids, Fluorinated

Central Study Contacts

Sanbin Wang

CONTACT

+8613187424131; sanbin1011@163.com

Xi Xiong

CONTACT

+8615987422538; 15987422538@163.com

Study Design

• Study Type: interventional
• Phase: phase 2
• Allocation: NA
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: July 7, 2026
• First Posted: July 13, 2026
• Study Start: July 3, 2026
• Primary Completion (Estimated): July 3, 2028
• Study Completion (Estimated): July 3, 2028
• Last Updated: July 14, 2026

Record last verified: 2026-07

Data Sharing

• IPD Sharing: Will not share