A Multicenter, Randomized, Open-Label Study of Haplo-Cord HSCT for the Treatment of Aplastic Anemia

Summary

Aplastic anemia (AA) is a bone marrow failure disorder characterized by pancytopenia and hypoplastic bone marrow caused by the decrease of hematopoietic stem cells. The pathogenesis of AA is complex and involves an abnormal hematopoietic microenvironment, hematopoietic stem cell/progenitor cell deficiencies and immunity disorders.

Currently, the standard treatment for AA includes immunosuppressive therapy (IST) based on anti-thymocyte/lymphocyte globulin (ATG/ALG) and cyclosporine A (CsA) or hematopoietic stem cell transplantation (HSCT). Although HLA-identical sibling allogeneic hematopoietic stem cell transplantation is considered the preferred transplant option for patients with severe aplastic anemia (SAA), only less than 30% of patients have an available HLA-matched sibling donor. In recent years, haploidentical hematopoietic cell transplantation (Haplo-HCT) has developed rapidly and has become an important alternative. However, graft failure and graft-versus-host disease (GVHD) remain significant factors limiting its efficacy.

Umbilical cord blood (UCB) contains a diverse population of hematopoietic stem cells. Compared with other sources, cord blood-derived hematopoietic stem cells are more primitive, more viable, and possess higher proliferative capacity. Therefore, cord blood transplantation, with its notable clinical therapeutic effects, has become an effective and reliable alternative to peripheral blood or bone marrow transplantation.

Currently, some transplant centers worldwide have adopted the coinfusion of UCB units with haplo-HCT (haplo-cord HCT) achieving preliminary efficacy in promoting engraftment and reducing the incidence of GVHD. A retrospective comparative study of haplo-cord HCT versus IST in patients with SAA identified haplo-cord HCT as the sole independent predictor for superior health-related quality of life (HRQoL) (P \< 0.0001).

Based on existing research and clinical experience, this study plans to investigate and further evaluate the safety and efficacy of haplo-cord HCT in the treatment of aplastic anemia. Primary endpoints will include overall survival, engraftment rate, disease-free survival, incidence of GVHD, CMV/EBV reactivation rate, donor chimerism dynamics, and immune reconstitution.

Conditions

• Aplastic Anaemia

Interventions

PROCEDURE

Haploidentical hematopoietic cell transplantation combined with unrelated cord blood stem cells

1\. Donor Stem Cells Infusion (Haploidentical hematopoietic cell transplantation combined with unrelated cord blood stem cells) Day 0: Intravenous infuse a single unit of unrelated cord blood stem cells( TNC≤2×10⁷/kg, CD34+ cells≤0.8×10⁵/kg, HLA match≥5/10 loci, and either matched ABO type or a cord blood unit of type O). This is followed, 6 hours after the cord blood infusion, by the infusion of donor haploidentical stem cells (TNC≥8×10⁸/kg, CD34+ cells≥4.0×10⁶/kg, and HLA match≥6/12 loci). 2. Conditioning Regimen: Day -7 to Day -6: Busulfan (Bu) 3.2mg/kg/day; Day -5 to Day -2: Cyclophosphamide (CTX) 160-200mg/kg. 3. Graft-versus-Host Disease Prophylaxis Regimen: Starting on the day before transplantation (Day -1): Cyclosporin A (CsA) 3mg/kg/day; Day +1 to Day +28: Mycophenolate Mofetil (MMF) 600mg/㎡/12h. 4. Infection Prophylaxis Regimen: Day -7 to Day -3: Ganciclovir (GCV): 5mg/kg/12h; Starting two days before transplantation (Day -2):Aciclovir (ACV): 250mg/㎡/8h.

PROCEDURE

Haploidentical hematopoietic cell transplantation

1\. Donor Stem Cell Infusion (Haploidentical hematopoietic cell transplantation) Day 0: Intravenous infuse of donor haploidentical stem cells (TNC≥8×10⁸/kg, CD34+ cells≥4.0×10⁶/kg, and HLA match≥6/12 loci). 2. Conditioning Regimen: Day -7 to Day -6: Busulfan (Bu) 3.2mg/kg/day; Day -5 to Day -2: Cyclophosphamide (CTX) 160-200mg/kg. 3. Graft-versus-Host Disease Prophylaxis Regimen: Starting on the day before transplantation (Day -1): Cyclosporin A (CsA) 3mg/kg/day; Day +1 to Day +28: Mycophenolate Mofetil (MMF) 600mg/㎡/12h. 4. Infection Prophylaxis Regimen: Day -7 to Day -3: Ganciclovir (GCV): 5mg/kg/12h; Continuous medication starting from two days before transplantation (Day -2): Aciclovir (ACV): 250mg/㎡/8h.

Sponsors & Collaborators

• The First Affiliated Hospital of Soochow University

  lead OTHER

Principal Investigators

• Depei Wu · The First Affiliated Hospital of Soochow University

• Xiaojin Wu · The First Affiliated Hospital of Soochow University

Study Design

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

NONE

Model

PARALLEL

Eligibility

Min Age

14 Years

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2025-10-01

Primary Completion

2028-09-01

Completion

2028-09-30

Countries

• China

Study Locations