P-295 Azacytidine 75 mg/m2 ×5 day in high-risk myelodisplastic syndromes and acute myeloid leukemia refractory/relapsed patients

Background: In higher-risk patients with myelodysplastic syndromes (MDS), the DNA methyltransferase inhibitors produce responses in 20% to 30% of patients and azacitidine (AZA) has demonstrated a survival advantage when comparedwith conventional therapies. Introduction: AZA is increasingly used in low-risk patients failing to respond to recombinant human erythropoietin (r-EPO) and in acute myeloid leukaemia patients (AML) with low marrow blast count or considered not fit for intensive chemotherapy. Purpose:We report a retrospective review on AZA treatment of MDS and AML patients in the common clinical practice of an Italian region (Liguria). Materials and Methods: Of 67 patients who started therapy only 46 patients received at least 4 courses of therapy, and were therefore considered evaluable for response and included in the study. Median age was 74 years (56-84), male/female ratio was 25/21. Nine patients (19%) had untreated AMLwithmarrow blasts ranging from 25 to 41%. MDS patients had RA or RARS (n.7, 19%), AREB-1 (n. 13, 35%), AREB 2 (n. 15, 40%), other forms (n. 2, 5%). In MDS patients the IPSS score was low/int-1 in 18 pts, int-2/high in 13 pts, not assessed in 7 pts. Twenty-six patients had a transfusion-dependent anaemia and the median number of packed erythrocyte units transfused weekly was 1 (range 1-2). All low and int-1 risk MDS patients had transfusion dependent anaemia and were unresponsive to r-EPO. Results: After a median of 8 courses (range 4-44) 26 patients (63%) achieved a haematological response (CR in 26%, PR in 24%, HI in 6,5%) whereas 20 (43,5%) were unresponsive. According to diagnosis and IPSS score responders were 6 (66,6%) among AML patients (CR 1, PR 4, HI 1), 10 (55,5%) in low/int-1 risk MDS patients and 7 (54%) among int-2/high risk MDS patients (CR 4, PR 3). Response was achieved after a median of 5 (range 3-6), 3 (range 2-12) and 5 (range 1-12) AZA courses in AML, low/int-1 risk and int-2/high risk MDS patients, respectively. Grade 1-2 myelotoxicity was commonly observed but no life threatening infections were reported. Eight-teen patients concomitantly received r-EPO therapy. Response lasted a median of 16 months (range 4-40) and median survival was 6 months in AML patients (4-9) and 23 months (6-48) in MDS patients. Conclusions: These preliminary data confirm efficacy and feasibility of AZA therapy in the common clinical practice, for both AML and all risk MDS patients.