Preemptive Therapy of Graft-vs-Host Disease Using Rabbit Antithymocyte Globulin

PreemptiveATG

Graft-vs-host disease (GVHD) causes substantial mortality, morbidity and poor quality of life after blood or marrow transplantation (BMT). In Alberta, we use antithymocyte globulin (ATG, given on days -2, -1 and 0) in addition to methotrexate and cyclosporine for GVHD prophylaxis. In spite of that, \~40% patients develop significant GVHD (grade 2-4 acute GVHD or chronic GVHD needing systemic immunosuppressive therapy). ATG at the dose we typically use (4.5 mg/kg) is relatively non-toxic. At higher doses, ATG could increase the likelihood of posttransplant infections or relapse. Thus an extra dose of ATG (on top of the routine 4.5 mg/kg) might be justified only for patients at high risk of developing significant GVHD. In our experience, low serum level of interleukin-15 (IL15) and high serum level of interleukin-2 receptor alpha (IL2Ra) on day 7 predict development of significant GVHD. Here we will test whether, compared to historical/concurrent controls, an extra dose of ATG (3 mg/kg on day 8) given to patients with low IL15 or high IL2Ra on day 7 reduces the incidence of significant GVHD, and improves survival free of relapse and GVHD, and quality of life.

2014-01-01

2017-06-30

2021-09-27

Terminated

Early phase I

70

Inclusion Criteria: 1. First allogeneic hematopoietic cell transplantation (second transplants are rare, typically performed for relapse of leukemia, in which case the likelihood of relapse is high, and there is the theoretical risk of increasing the likelihood further with ATG). 2. Conditioning including ATG 4.5 mg/kg (the predictive value of IL15 and IL2Ra levels was determined in patients whose conditioning included 4.5 mg/kg or ATG). 3. Age \>17 (the predictive value of IL15 and IL2Ra levels has not been studied in children). Exclusion Criteria: 1. Nonmyeloablative conditioning (possible risk of ATG increasing relapse). 2. Active viral infection (risk of worsening of the viral infection with ATG). 3. Neutropenic fever with hypotension. In such case, the ATG can be given on day 9 (instead of day 8) if patient no longer has hypotension. 4. Hypoxemia. In such case, the ATG can be given on day 9 (instead of day 8) if patient no longer has hypoxemia. 5. History of anaphylactic reaction to Thymoglobulin or another rabbit blood protein.

{'studyType': 'INTERVENTIONAL', 'phases': ['PHASE2'], 'designInfo': {'allocation': 'NA', 'interventionModel': 'SINGLE_GROUP', 'primaryPurpose': 'PREVENTION', 'maskingInfo': {'masking': 'NONE'}}, 'enrollmentInfo': {'count': 70, 'type': 'ACTUAL'}}

2023-11-30