A conditioning regimen of clofarabine plus total body irradiation prior to allogeneic hematopoietic stem cell transplantation (HSCT) led to a two-year overall survival (OS) rate of 43% in patients with high-risk acute leukemia, according to research presented at the 10th Annual Meeting of the Society of Hematologic Oncology.
Ali Atoui, MD, of the American University of Beirut in Lebanon, and colleagues, conducted the observational retrospective study at the American University of Beirut Medical Center and Saint-Antoine Hospital in Paris, France.
Dr. Atoui and colleagues conducted the research to investigate the use of conditioning regimens with clofarabine, an immunosuppressive purine analog, plus higher doses of total body irradiation ranging from four to eight gray (Gy).
The study included 23 patients, most of whom were male (61%), with a median patient age of 43 years (range, 21-78). Half of the patients had acute myeloid leukemia, while half had acute lymphoblastic leukemia. Most patients (61%) were in complete remission when they received a transplant, while 35% had refractory disease. All patients received clofarabine and most received four Gy total body irradiation (87%), while 13% received eight Gy. Most patients received anti-thymocyte globulin (65%), and the majority of patients were matched to a related donor for transplant (see TABLE 1).
The two-year progression-free survival rate was 48% and the two-year overall survival rate was 43% at a median follow-up of 22.4 months. The transplant-related mortality rate was 4% at 100 days after transplant and was 13% at one year after transplant. The graft-versus-host disease one-year relapse-free survival rate was 22%.
TABLE 1. Transplant Donor Types vs Percent of Patients
|Transplant donor source type||Patient percentage|
|Matched related donor||39%|
|Matched unrelated donor||17%|
|Haploidentical related donor||35%|
|Unrelated cord blood donor||9%|
“The use of clofarabine in combination with [total body irradiation] as a conditioning regimen for allogeneic stem cell transplant in high-risk acute leukemia confers disease control with low transplant-related mortality,” Dr. Atoui and colleagues concluded.
Atoui A, Dulery R, Terro K, et al. Clofarabine and Total Body Irradiation as a Conditioning Regimen for Allogeneic Stem Cell Transplantation in High-Risk Acute Leukemia. Abstract #CT-028. Presented at the 10th Annual Meeting of the Society of Hematologic Oncology, September 28-October 1, 2022.