ChemGenex Pharmaceuticals presents clinical results of Omapro drug at ASH meeting

Dec 7 2009

ChemGenex Pharmaceuticals Limited (ASX:CXS) announced today updated clinical data showing that Omapro™ (omacetaxine mepesuccinate) produced durable hematologic and cytogenetic responses in chronic myeloid leukemia (CML) patients who have failed treatment with imatinib and who have developed the Bcr-Abl T315I mutation. New data was presented at a pre-conference press showcase at the 51^st Annual American Society of Hematology Annual Meeting in New Orleans, Louisiana.

At the press conference titled "Advances in Diagnosing and Treating Leukemia and Myeloproliferative Disorders" Dr. Jorge Cortes, MD, Professor of Medicine and Deputy Chair in the Department of Leukemia at The University of Texas, MD Anderson Cancer Center, a lead investigator in the study, presented data on behalf of a team including investigators from ChemGenex and leading U.S. and European clinical research centers. Completing his presentation, Dr Cortes concluded that Omapro represents a new potential therapy for patients with T315I+ CML.

Data were presented from 81 CML patients: 49 in chronic phase, 17 in accelerated phase and 15 in blast phase. Highlights of the data were:

• Complete hematologic responses (CHR) in 86% of chronic phase patients, median response duration 9 months
• Total cytogenetic response rate of 41% in chronic phase patients, with major cytogenetic response (MCyR) rate of 27%
• Overall hematologic responses in 35% of accelerated phase patients (median duration 7 months)
• Overall hematologic responses in 47% of blast phase patients (median duration 2 months)
• Investigators reported that omacetaxine is safe for self-administration, is well tolerated, and that reversible and manageable myelosuppression is the most common side effect

“We are delighted with the positive data presented today that continues to show that Omapro can provide clinical benefit to patients in this very difficult to treat sub-set of CML where there are no other approved treatment options,” said Greg Collier, Ph.D., Managing Director and Chief Executive Officer of ChemGenex. “We would like to thank Dr. Cortes and all of our investigators for their efforts to produce this data. These results support our regulatory filings, and we look forward to working with the agencies in the U.S. and Europe over the next several months as we seek approval for Omapro in 2010.”

Applications for marketing approval for Omapro are currently under review by the U.S. Food & Drug Administration (priority review), and the European Medicines Evaluation Agency.