Unrelated Donor Transplant Versus Immune Therapy in Pediatric Severe Aplastic Anemia

The purpose of this study is to determine the feasibility of comparing outcomes of patients treated de novo with immunosuppressive therapy (IST) versus matched unrelated donor (MUD) hematopoietic stem cell transplant (HSCT) for pediatric acquired severe aplastic anemia.

Conducting Institutions:

Children's Hospital Boston, Dana-Farber Cancer Institute

Overall PI:

Site-responsible Investigators:

Contacts:

Eligibility Criteria

Inclusion Criteria:

  1. Confirmed diagnosis of idiopathic SAA, defined as:

       -  Bone marrow cellularity <25%, or <30% hematopoietic cells and central pathology
  review consistent with SAA (see laboratory manual of procedures).

       -  Two out of three of the following (in peripheral blood): neutrophils <0.5
  x109/L, platelets <20 x109/L, reticulocyte count <60 x109/L with hemoglobin
  <8g/dL.

  2. Age ≤25 years old.

  3. No suitable fully matched related donor available (minimum 6/6 match for Human
     Leukocyte antigen (HLA) -A and B at intermediate or high resolution and DRB1 at high
     resolution using DNA based typing).

  4. Unrelated donor or donors noted on National Marrow Donor Program (NMDP) search who
     are well matched (9/10 or 10/10 for HLA-A, B, C, DRB1, and DQB1 using high
     resolution). See section 2.5.1 for details on central confirmation of the
     availability of donors required.

  5. Signed informed consent for the randomized trial by patient and/or legal guardian.

  6. Adequate organ function defined as in the judgment of the investigator, there is not
     irreversible organ damage that would preclude the patient from meeting the organ
     function inclusion criteria for HSCT listed in section 2.3.4 by the intended time of
     HSCT (6-8 weeks after randomization) or preclude patients from receiving horse ATG.

Exclusion Criteria:

  1. Inherited bone marrow failure syndromes (IBMFS). The diagnosis of Fanconi anemia must
     be excluded by diepoxybutane (DEB) or equivalent testing on peripheral blood or
     marrow. Dyskeratosis congenita must be excluded by testing of telomere
     length,Shwachman Diamond syndrome must be excluded by testing serum trypsinogen in
     patients age <3 or or isoamylase for children ≥3 (see section 4.2.3.1 for details of
     the required evaluations to exclude IBMFS).

  2. Clonal cytogenetic abnormalities or fluorescence In Situ Hybridization (FISH) pattern
     consistent with pre-myelodysplastic syndrome (pre-MDS) or MDS on marrow examination
     (see section 4.2.3.1 for details of the required MDS FISH panel).

  3. Known severe allergy to horse ATG.

  4. Prior allogeneic stem cell transplant.

  5. Prior solid organ transplant.

  6. Seropositive for the human immunodeficiency virus (HIV).

  7. Active Hepatitis B or C determined by serology and/or NAT.

  8. Female patients who are pregnant or breast-feeding.

  9. Prior malignancies except resected basal cell carcinoma or treated cervical carcinoma
     in situ.