News & Events

ChemGenex Pharmaceuticals Limited (ASX:CXS) announced today the completion of its New Drug Application (NDA) submission to the U.S. Food & Drug Administration (FDA) for OMAPRO^TM (omacetaxine mepesuccinate). OMAPRO^TM is being developed for the treatment of patients with chronic myeloid leukemia (CML) who have failed treatment with imatinib and who have developed the Bcr-Abl T315I mutation. Imatinib, a tyrosine kinase inhibitor (TKI), is the first-line standard of care for patients with CML. OMAPRO^TM is a first-in-class cetaxine which works differently from imatinib, and the second-line TKIs nilotinib and dasatinib.

OMAPRO^TM has received Orphan Drug designation in the U.S. and in the European Union, and has received fast track status from the FDA. OMAPRO^TM demonstrated clinical benefit in the pivotal Study 202, in CML patients who had failed imatinib and have the T315I mutation. Interim data were recently presented at the American Society of Clinical Oncology Annual Meeting.

"If approved, OMAPRO^TM would be the first treatment specifically indicated for CML T315I patients, many of whom have no therapeutic options," said Adam R. Craig MD, PhD, Senior Vice President and Chief Medical Officer. "We thank the investigators, their research staff and patients for participating in the pivotal study."

If the FDA grants priority review for OMAPRO^TM the examination period is expected to be approximately six months. If approved for marketing by the FDA following priority review, the launch of OMAPRO^TM would be scheduled for mid-2010.

Greg Collier PhD, ChemGenex's Chief Executive Officer and Managing Director, said, "The submission of the NDA for OMAPRO^TM is a major milestone in the development of this novel product and we are now one step closer to delivering a new treatment for patients in an area of unmet medical need. This submission is a significant achievement in our strategic goal to commercialize OMAPRO^TM independently in the U.S. oncology market."

About Chronic Myeloid Leukemia (CML) and the Bcr-Abl T315I Mutation
Chronic myeloid leukemia (CML) is a cancer of the bone marrow with a worldwide revalence of approximately 200,000 patients. The bone marrow is responsible for the production of specialized cells that constitute blood; these cells include red blood cells (to carry oxygen around the body), thrombocytes (to help stop bleeding) and certain white cells (part of the body's defense system against infection). In patients with CML the cell production system is diseased and defective. Cells multiply uncontrollably and do not fully develop (differentiate) into functional blood cells.

The majority of newly diagnosed CML patients initially respond well to treatments with drugs called tyrosine kinase inhibitors (TKIs). However, a significant proportion of patients fail or become intolerant to one or more TKIs. In many of these situations the cause of failure can be traced to the emergence of Bcr-Abl mutations. A common mutation called T315I renders CML resistant to all currently approved TKIs, and has created a significant unmet medical need in the management of CML.

About OMAPRO^TM (omacetaxine mepesuccinate) Omacetaxine is administered subcutaneously and acts differently from TKIs. It may have a therapeutic advantage for patients who have failed TKIs. Omacetaxine is currently in global phase 2/3 clinical trials for CML and has been granted Orphan Drug designations by the U.S. Food and Drug Administration (FDA) and European Medicines Agency (EMEA) as well as Fast Track status by the FDA. Omacetaxine mepesuccinate is a first-in-class cetaxine with demonstrated clinical activity as a single agent in a range of hematological malignancies.

Omacetaxine has a novel mechanism of action, specifically binding to the ribosomal A-site cleft and inhibiting protein translation of short-lived oncoproteins that are upregulated in leukemic cells (particularly Cyclin-D1, Mcl-1 and c-Myc). In addition, pre-clinical research presented at the 14th Congress of the European Hematology Association (EHA) in Berlin, Germany this summer, demonstrated that omacetaxine kills human CML stem cells that are known to be insensitive to TKIs.