Treatment of Patients with Low-Risk Myelodysplastic Syndromes Receiving Azacitidine Who Are Enrolled in AVIDA, a Longitudinal Patient Registry.

With the development of new agents such as azacitidine, a hypomethylating agent approved for the treatment of all 5 MDS subtypes, chemotherapy for MDS patients has become more common. Nonetheless, the use of hypomethylating agents in patients with low-risk MDS in the community-based setting has not been well characterized. AVIDA is a longitudinal, multicenter patient registry designed to prospectively collect data from community-based hematology clinics on the natural history and management of patients with MDS and other hematologic disorders, including acute myeloid leukemia, who are treated with azacitidine. The characteristics and transfusion status of patients enrolled in AVIDA who had an International Prognostic Scoring System (IPSS) risk classification score of low/intermediate-1 at baseline are presented. As of August 1, 2008, 130 (91 males, 39 females) patients with an IPSS score of low/intermediate-1 have been enrolled in AVIDA; 45 (35%) with low and 85 (65%) with intermediate-1. Median age is 74.7 years (range, 41.4–91.4), and the majority (80%) had a baseline ECOG performance status of 0 or 1. Median time from first MDS diagnosis until azacitidine treatment was 7.5 months (range, 0 to 108), suggesting a delay in treatment of these patients compared with high risk patients (n = 55) in the registry (1 month). At baseline, 103/130 (79%) patients had <5% bone marrow blasts and 109/130 (84%) had a ‘good’ karyotype. Cytopenias were reported in 0 or 1 lineage for 69/130 (53%) patients and in 2 or 3 lineages for 60/130 (46%) patients; number of cytopenias at baseline is unknown for 1 (1%) patient. A total of 483 cycles of azacitidine have been administered either by subcutaneous (43%) or intravenous (57%) infusion. A total of 126 patients with an IPSS score of low/intermediate-1 have received a median of 3 cycles (range, 1 to 15); 94/126 (75%) patients have received at least 2 cycles. Transfusion independence was defined as no transfusions for at least 56 days. The first day of the 56-day period with no transfusions was noted as the time at which patients first achieved transfusion independence. Transfusion data are available for 52 patients who were receiving RBC transfusions at baseline and have received at least 2 cycles. Of these patients, 24/52 (46%) have achieved RBC transfusion independence while receiving azacitidine; 16/24 (67%) achieved RBC transfusion independence during the first 2 cycles. Thirteen patients were receiving platelet transfusions at baseline and have received at least 2 cycles of therapy. Of those patients 8/13 (62%) have achieved platelet transfusion independence; 7/8 (88%) achieved platelet transfusion independence during the first 2 cycles. In these low-risk patients, azacitidine was generally well tolerated; the most common adverse events were anemia (20%), thrombocytopenia (13%), nausea (11%), constipation (10%), fatigue (10%), and neutropenia (10%). These data demonstrate that patients with an IPSS score of low/intermediate-1 are being treated in the community-based setting and can achieve transfusion independence while receiving azacitidine. AVIDA provides a unique opportunity to characterize the MDS patient population that is receiving chemotherapy in the community-based setting. The effect of azacitidine on the outcome and overall quality of life in this patient subpopulation will become clearer as more patients with low-risk MDS are treated.