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Individualized Dose Study of ATG in Haploidentical Hematopoietic Stem Cell Transplantation

Phase 2
Active, not recruiting
Conditions
Haploidentical Hematopoietic Stem Cell Transplantation
Interventions
Drug: Antithymocyte Globulin
Registration Number
NCT04778618
Lead Sponsor
Chinese PLA General Hospital
Brief Summary

The purpose of this study is to determine the response and toxicity rate of two different dosages (Individualized dosage VS. fixed dosage) of ATG as a prophylaxis for acute GVHD in haploidentical peripheral blood stem cell transplantation (haplo-PBSCT).

Detailed Description

Acute graft-versus-host disease (aGvHD) is an important complication of haplo-HSCT. The Seattle group initially introduced the use of ATG as a treatment for acute graft-versus-host disease (aGVHD) in allogeneic hematopoietic stem cell transplantation (haplo-PBSCT) recipients. Presently, in both myeloablative and reduced-intensity conditioning (RIC) haplo-PBSCT, ATG is part of postengraftment immunosuppressive regimens.

The regimens for prophylaxis of GVHD based on 10mg/kg rabbit anti-human thymocyte immunoglobin (ATG, Thymoglobulin®, Genzyme Polyclonals S.A.S) effectively reduced the occurrence of grade II-IV aGvHD. However, the incidence of cytomegalovirus (CMV) and EB virus (EBV) reactivation were higher due to a slower immune reconstitution. The 100-day cumulative incidence of CMV and EBV viremia were both over 70% in our unmanipulated haplo-PBSCT program. The optimal dose of ATG balancing the efficacy of GVHD prophylaxis and the risk of virus reactivation in haplo-PBSCT remains unknown.

Reports on the pharmacokinetics of Thymoglobulin in allo-HSCT revealed a high variability. Recent pharmacokinetic studies have shown that the half-life of total ATG after transplant is longer than the active ATG (which is available to bind to human lymphocytes and causes the desired immunological effects). And active ATG appears more associated with pharmacodynamics effects. The investigators found that virus reactivation and acute GVHD were highly affected by ATG exposure (area under the curve, AUC) in previous cohort study. The investigators have found an optimal range of active ATG exposure balancing the efficacy of GVHD prophylaxis and the risk of virus reactivation. The incidence of CMV reactivation and III-IV aGVHD reduced to 60%, 6% respectively.

The results suggested that Individualized dosing of ATG has a potential advantage in balancing the efficacy of GVHD prophylaxis and the risk of virus reactivation in haplo-PBSCT. This may improve the survival and quality of life of patients undergoing haplo-PBSCT. A prospective randomized trial is required to compare the efficacy of Individualized dosage of ATG as a prophylaxis for acute GVHD in haplo-PBSCT.

Recruitment & Eligibility

Status
ACTIVE_NOT_RECRUITING
Sex
All
Target Recruitment
63
Inclusion Criteria
  1. Confirmed diagnosis of hematological malignancies refer to the 2016 WHO classification.
  2. Aged 14 to 60 years.
  3. Karnofsky or Lansky performance status [27] ≥ 70%. Please refer to Appendix A.
  4. First transplantation.
  5. Adequate organ function
  6. Patient and/or legal guardian must sign informed consent for HSCT.
Exclusion Criteria
  1. Ex-vivo T-cell depleted grafts.
  2. Pregnancy or breast-feeding or unwilling to use proper contraception.
  3. Unable to assess whether the malignancy is in complete remission.
  4. History of hypersensitivity to any biological product.
  5. Sensibility to rabbit proteins or previous treatment with Thymoglobuline®.
  6. Subjects with uncontrollable systemic infection (viral, bacterial or fungal).
  7. Participation in other trial in which the dose of Thymoglobuline® is fixed other than individualized dose.
  8. Unable to sign the informed consent form.

Study & Design

Study Type
INTERVENTIONAL
Study Design
SINGLE_GROUP
Arm && Interventions
GroupInterventionDescription
Individual dose of ThymoglobulinAntithymocyte GlobulinIndividual dose of Thymoglobulin (r-ATG) : Individual dose of ATG was Intravenous infused every day from day -5 to day -2 (total ATG dose was calculated based on pharmacokinetic index, within a range of 6 mg/kg to 10mg/kg)
Primary Outcome Measures
NameTimeMethod
The cumulative incidences of CMV reactivation180 days after transplantation

The cumulative incidences of CMV reactivation in participants after transplantation, tested by realtime PCR

The cumulative incidences of EBV reactivation180 days after transplantation

The cumulative incidences of EBV reactivation in participants after transplantation, tested by realtime PCR

Secondary Outcome Measures
NameTimeMethod
Engraftment28 days after transplantation

Neutrophil engraftment was defined as the first day with a neutrophil count \> 0.5 × 10\^9/L on three consecutive days postnadir; platelet engraftment was defined as the first day with a platelet count \> 20 × 10\^9/L without transfusion for five consecutive days postnadir.

Relapse1 years after transplantation

Defined as reappearance of leukemic blasts in peripheral blood or ≥5% blasts in BM or reappearance or new appearance of extramedullary leukemia.

Overall survival (OS)1 year after transplantation

Defined as the time from transplantation to last follow-up or death due to any cause

The cumulative incidences of aGVHD (refer to MAGIC criteria)100 days after transplantation

Defined as the proportion of participants who developed acute GVHD

The cumulative incidences of cGVHD (refer to NIH criteria)2 years after transplantation

cGvHD was diagnosed and graded according to the 2014 National Institutes of Health (NIH) consensus criteria: mild, moderate or severe respectively.

Nonrelapse mortality (NRM)1 years after transplantation

Defined as death due to causes other than malignancy relapse

Disease-free survival (DFS)1 years after transplantation

Defined as survival with no evidence of relapse or progression.

Trial Locations

Locations (1)

Chinese PLA General Hospital

🇨🇳

Beijing, Beijing, China

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