Array BioPharma announced updated clinical safety and efficacy data on ARRY‑614 in patients with myelodysplastic syndromes at the 2013 Annual Meeting of the American Society of Hematology. ARRY-614 is a potent inhibitor of p38/Tie2 with a mechanism of action distinct from drugs currently available to treat MDS. It is being studied in an ongoing dose-escalation trial in IPSS low/intermediate-1 risk MDS patients, representing a population of more than 100,000 patients in developed countries. The dose-escalation portion of the trial established the maximum tolerated dose, and subsequent expansion cohorts have been fully enrolled. Of patients currently evaluable for efficacy, 21% achieved a Hematologic Improvement. Of particular interest, 44% of platelet-transfusion dependent patients achieved Transfusion Reduction, and 31% achieved Transfusion Independence. Lower risk MDS patients with severe low platelet counts have a particularly poor prognosis. The most common treatment-related adverse events across all doses were rash, nausea, and atrial fibrillation. The majority of these events were mild or moderate in severity. "ARRY-614 was generally well tolerated in these lower-risk MDS patients and I am particularly encouraged with the platelet effects observed in patients with thrombocytopenia, including platelet transfusion independence," said Guillermo Garcia-Manero, M.D., Professor, Department of Leukemia, Division of Cancer Medicine, The University of Texas MD Anderson Cancer Center.