Thalidomide produces transfusion independence in long-standing refractory anemias of patients with myelodysplastic syndromes

Thalidomide was administered to 83 patients with myelodysplastic syndrome ( FADS), starting at 100 mg by mouth daily and increasing to 400 mg as tolera ted. Thirty-two patients stopped therapy before 12 weeks (minimum period fo r response evaluation), and 51 completed 12 weeks of therapy. International Working Group response criteria for MDS were used to evaluate responses. I ntent-to-treat (ITT) analysis classified all off-study patients as nonrespo nders. Off-study patients belonged to a higher risk category (P = .002) and had a higher percentage of blasts in their pretherapy bone marrow than pat ients who completed 12 weeks of therapy (P = .003). No cytogenetic br compl ete responses were seen, but 16 patients showed hematologic improvement, wi th 10 previously transfusion-dependent patients becoming transfusion indepe ndent. Responders had lower pretherapy blasts (P = .016), a lower duration of pretherapy platelet transfusions (P = .013), and higher pretherapy plate lets (P = .003). Among responders, 9 had refractory anemia (RA); 5 had RA w ith ringed sideroblasts; and 2 had RA with excess blasts. By ITT analysis, 19% of patients (16 of 83) responded, and when only evaluable patients were analyzed, 31% (16 of 51) responded. It was concluded that thalidomide, as a single agent, is effective in improving cytopenias of some MDS patients, especially those who present without excess blasts. (C) 2001 by The America n Society of Hematology.