Azacitidine for the Treatment of Lower Risk Myelodysplastic Syndromes

BACKGROUND: Azacitidine induces responses and prolongs overall survival compared with conventional care regimens in patients who have high-risk myelodysplastic syndromes (MDS). However, limited data are available concerning the efficacy and safety of azacitidine in patients who have lower risk MDS. METHODS: The authors retrospectively evaluated 74 patients with International Prognostic Scoring System low-risk or intermediate I-risk MDS, who received azacitidine on a national named patient program. At baseline, 84% of patients were transfusion-dependent, 57% had received erythropoietin, and 51% were aged >70 years. Azacitidine was administered subcutaneously for 5 days (n = 29 patients), 7 days (n = 43 patients), or 10 days (n = 2 patients) every month at a dose of 75 mg/m(2) daily (n = 45 patients) or at a fixed dose of 100 mg daily (n = 29 patients) and for a median of 7 cycles (range, 1-30 cycles). RESULTS: According to the 2006 International Working Group criteria, overall response rate (ORR) was 45.9%, including complete responses (10.8%), partial responses (9.5%), hematologic improvements (20.3%), and bone marrow complete responses (5.4%). The ORR was 51.6% in 64 patients who completed >= 4 cycles of treatment. The median duration of response was 6 months (range, 1-30 months). After a median follow-up of IS months, 71% of patients remained alive. A survival benefit was observed in responders versus nonresponders (94% vs 54% of patients projected to be alive at 2.5 years, respectively; P < .0014). The most common grade 3 or 4 adverse events were myelosuppression (21.6%) and infection (6.8%). CONCLUSIONS: The current results indicated that azacitidine may be a feasible and effective treatment for patients with lower risk MDS. Cancer 2010;116:1485-94. (C) 2070 American Cancer Society.