Retreatment with immunosuppression for 23 patients with refractory or relapsed severe aplastic anemia

Objective: This study aims to evaluate the efficacy and safety of secondary immunosuppressive therapy (IST) in refractory or relapsed severe aplastic anemia. Methods: The hematologic response and safety of 23 patients with refractory or relapsed SAA treated with secondary IST (including ATG/ALG + cyclosporine or HD-CTX) in our hospital were retrospectively analyzed. Results: A total of 23 patients were involved, including 11 males and 12 females, with a median age of 21 (11-62) years. In the refractory group, the interval of IST was 7 (6-12) months. In the relapsed group, on the other hand, the interval between two courses of IST was 39 (14-51) months. At 6 months after IST, the overall response rate was 69.5% (16/23) ; 60% (6/10) of the refractory group vs 77% (10/13) of the relapsed group; 64% (7/11) of the ATG/ALG group vs 75% (9/12) of the HD-CTX group. Among the patients who got the hematologic response, two patients relapsed again, all of them from the relapse group. After the third IST, they got the response again. Conclusion: The second IST is safe and effective for refractory and relapsed SAA patients; the early serologic reaction should be paid attention to when using the same ATG/ALG, and the risk can be reduced by changing the type of ATG/ALG or other IST programs. The third IST can still obtain the treatment response for the second relapse patients.