High-dose cyclophosphamide for severe aplastic anemia: long-term follow-up

Abstract

Severe aplastic anemia (SAA) is a life-threatening bone marrow failure disorder that can be treated with bone marrow transplantation, immunosuppressive therapy, and high-dose cyclophosphamide. Here, we report long-term follow-up on 67 SAA patients (44 treatment-naive and 23 refractory) treated with high-dose cyclophosphamide. At 10 years, the overall actuarial survival was 88%, the response rate was 71% with the majority being complete, and the actuarial event-free survival was 58% in 44 treatment-naive SAA patients. Patients with refractory SAA fared less well after high-dose cyclophosphamide therapy; at 10 years, overall actuarial survival, response, and actuarial event-free survival rates were 62%, 48%, and 27%, respectively. High-dose cyclophosphamide is highly effective therapy for severe aplastic anemia. Large randomized controlled trials will be necessary to establish how results of high-dose cyclophosphamide compare with either bone marrow transplantation or standard immunosuppressive regimens, such as antithymocyte globulin and cyclosporine.

Figure 1

Overall survival after high-dose cyclophosphamide therapy. Overall survival for 44 treatment-naive patients (top line) and 23 patients refractory to prior immunosuppressive therapy (bottom line). P = .03 (log-rank test).

Figure 2

Failure-free survival after high-dose cyclophosphamide therapy. Failure-free survival for 44 treatment-naive patients (top line) and 23 patients refractory to prior immunosuppressive therapy (bottom line). P = .07 (log-rank test).