Effect of androgens on the response to antithymocyte globulin in patients with aplastic anaemia.

30 patients with aplastic anaemia (18/30 with severe aplastic anaemia) were prospectively randomized to be treated with 100 mg/kg ATG with or without the oral androgen Methenolone (3 mg/kg). 15 of 30 patients responded. Among the 15 patients receiving ATG plus androgen, 11 patients (73%) responded, including 8 complete and 3 partial responses. 4 of the 15 patients (31%) receiving ATG only responded, including 2 complete and 2 partial responses. The difference in response rate was statistically significant (p = 0.01). The survival rate in the total population of 30 patients was 64%. The survival rate in the group receiving ATG plus androgen was 87%; in the group receiving ATG only it was 43%. The difference in survival rates between both groups did not reach statistical significance (p = 0.15). Toxicity of ATG and androgens was considerable but manageable. These data support the result of the recent European reevaluation of a large pool of patients by the EBMT (39), that androgens in addition to ATG increase survival in patients with aplastic anaemia. They are, however, in contradiction to a controlled American study showing no benefit of a combined treatment with androgens as compared to ATG only. Further controlled studies on a larger number of patients are indicated to determine the therapeutic efficacy of androgens in addition to immunosuppression in aplastic anaemia.