According to a new study, conditioning chemotherapy that contains alemtuzumab may improve outcomes related to graft-versus-host disease (GVHD) and relapse in children and young adults with hematologic malignancies. Study findings were presented at the 2021 American Society of Pediatric Hematology/Oncology (ASPHO) meeting.
Alemtuzumab is a CD52-directed monoclonal antibody used to treat GVHD, the use of which can result in susceptibility to infections due to immunosuppressant effects.
The study was a retrospective analysis of patients seen at Texas Children’s Hospital in Houston, Texas, who received unrelated donor (UD) allogeneic hematopoietic stem cell transplantation (HSCT) and were given weight-based dosages of intravenous alemtuzumab. Multiple outcomes were assessed, such as overall survival (OS), GVHD/relapse-free survival (GRFS), and others.
A total of 84 patients were evaluated in this study, and the median patient age was 12 years (range, 1-22). The donor type in 59.5% of patients was a matched UD, and in 40.5% it was a mismatched UD. Most patients (75%) received myeloablative conditioning.
The most common malignant diagnosis was acute lymphoblastic leukemia in 52.4% of patients, followed by acute myeloid leukemia/myelodysplastic syndrome in 28.6%, with 1.2% of patients having other leukemias. Hodgkin lymphoma was found in 8.3% of patients, and non-Hodgkin lymphoma was present in 9.5%.
The 1-year OS rate was 72.4% and the 3-year OS was 61.4%. The 1-year GRFS rate was 61.9% and the 3-year GRFS was 51.7%.
Treatment-related mortality occurred with a rate of 16.1% at 1 year. Acute GVHD of grades 2 to 4 occurred at an incidence of 22.6%, with 9.5% of patients experiencing grade 3 or 4 acute GVHD. Chronic GVHD occurred with an incidence of 11.9%, with 3.6% of patients having extensive chronic GVHD. The 1-year rate of relapse was 21.3%, and the 3-year rate was 31.7%. Infections were common following HSCT and were involved in 35% of patient deaths.
The study investigators concluded that conditioning chemotherapy containing alemtuzumab mitigated severe GVHD in patients of this study who had received UD HSCT. Rates of relapse, GRFS, and TRM were also favorable. They recommended that further research be directed at improving infection-prevention strategies for patients receiving alemtuzumab.
Patel S, Lulla P, Jang A, et al. Outcomes of conditioning with alemtuzumab in unrelated donor transplant for hematologic malignancies in children and young adults. Paper presented at: 2021 American Society of Pediatric Hematology/Oncology meeting; April 21-23, 2021; virtual.