Immunosuppressive therapy

Antithymocyte globulin (ATG) has shown activity in MDS patients in several small series. The National Heart, Lung, and Blood Institute conducted a phase II trial including 25 MDS patients with less than 20% blasts. Of all the patients studied, 11 (or 44%) responded and became transfusion-independent after ATG (three complete responses, six partial responses, and two minimal responses).[18] Multivariate analysis identified HLA-DR-15 (phenotype) expression, briefer period of red cell transfusion dependence, and younger age as predictors of response to ATG.[19] One study used alemtuzumab to treat a heavily preselected population of lower-risk MDS patients, in whom the response rate was 80%.[20]