Decitabine Combined with FB3 As Conditional Regimen for Elderly Acute Myeloid Leukemia Patient with Allogeneic Hematopoietic Stem Cell Transplantation

Background

Acute myeloid leukemia (AML) is a malignant hematologic disease with high incidence in the elderly peoples. Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is an important method for the treatment of AML. However, elderly patients with AML are unable to receive myeloablative conditioning, and transplant related mortality (TAM) is significantly higher than that of young AML patients. How to reduce TAM in elderly AML patients, improve the efficacy of allo-HSCT, and further expand the applicable population of allo-HSCT is the focus of clinical research.

Patients and methods

According to the clinical trial (ChiCTR-IIR-16008182), elderly patients with AML used Decitabine (Dec) combined with FB3 as conditional regimen (20mg/m² decitabine on day -11∽-7, 30mg/m² Fludarabine on day -6∽-2, 130mg/m² busulfan on day -4∽-2). The primary outcome of the trial was relapse after transplantation, and the secondary outcomes were chronic graft versus host disease (cGVHD) and the safety of treatment.

Results

From Mar 2016 to Jun 2018, 19 elderly patients with AML in our center include in the study. The median age was 62 (60-66) years. According to cytogenetics and molecular mutation, 8 patients were intermediate risk and 11 patients were unfavorable risk. HLA matched HSCT was performed in 7 patients, and HLA haploidentical HSCT in 12 patients. All of the patients achieved complete donor chimerism by day 28 after HSCT. Patients achieved ANC engraftment at 15 (10-19) days and PLT engraftment at 19 (12-26) days. Five patients relapsed after transplantation, and 4 of them died; one patient died of severe acute graft versus host disease (aGVHD) and pulmonary infection. The main adverse reactions during the conditioning treatment were dizziness, nausea, vomiting, diarrhea and oral ulcers. ALL symptoms were relieved after the symptomatic treatment. Three patients had a mild elevated transaminase and improved after liver-protecting treatment. Till now, the leukemia-free survival and overall survival were 73.68%.

Conclusion

Dec combined with FB3 as conditional regimen was well tolerated and can achieve ideal survival. The multicenter, randomized controlled clinical study will conduct to further verify its effectiveness and safety.

Key Words: Decitabine, FB3, Elderly, Acute myeloid leukemia patient, Allogeneic hematopoietic stem cell transplantation