Response Rates Using International Working Group (Iwg) Criteria In Patients With Myelodysplastic Syndromes (Mds) Treated With Azacitidine.

The CALGB conducted a series of clinical trials with azacitidine (Vidaza®) administered subcutaneously or intravenously in patients with MDS using the FAB classification (JCO 2002; 20:2429). Since the publication of these CALGB studies (8421, 8921, 9221), new response criteria for evaluating new treatments for MDS have been published by the IWG (Blood 2000; 96:3671). Two general differences between the CALGB and IWG response criteria are the required duration of improvement (CALGB: ≥4 weeks; IWG: ≥8 weeks) and peripheral blood values (CALGB: different criteria for hemoglobin targets for males and females; IWG: same criteria for males and females). The results reported here are based on re-collected data from patients described in the published report. After applying the IWG response criteria, the overall response rate (CR+PR+HI) in the azacitidine groups were similar across studies 8421, 8921, and 9221: 44% (21/48), 40% (28/70), and 48% (47/99), respectively.