Sorafenib as salvage therapy in refractory relapsed acute myeloid leukemia with positive FLT3 mutation

Objective: To analyze the effect of sorafenib as salvage therapy used before and/or after allogeneic hematopoietic stem cell transplantation (allo-HSCT) in refractory relapsed FLT3-positive acute myeloid leukemia (AML).

Methods: A total of 16 patients with refractory relapsed FLT3-positive AML, including 10 refractory relapsed pre-transplantation and 6 relapsed after allo-HSCT, were enrolled in this retrospective study. Sorafenib treatment protocols included sorafenib in combination with chemotherapy inducing remission, and sorafenib monotherapy as mauntenance treatment after complete remission (CR).

Results: Thirteen of the 16 patients achieved CR after one or two courses of induction therapy, including 7 refractory relapsed pre-transplantation and 6 relapsed after allo-HSCT. With a median follow up of 472 (range, 59-1569) days post-transplantation, 12 patients survived and 4 died. Causes of death included leukemia relapse (n=3) and acute graft-versus-host disease (n=1). The 2-year overall and disease-free survival post-transplantation of the 16 patients were (75.0±10.8) % and (50.5±13.7) % respectively. The main side effect of sorafenib was the skin rash. The incidence of rash was lower in the patients used sorafenib pre-transplantation than those post-transplantation (30.0% vs 75.0%, P=0.043).

Conclusions: Sorafenib used as salvage therapy befor and/or after transplantation for refractory relapsed FLT3-positive AML could reduce the relapse rate and improve the survival.