Omapro™ Featured During ASH Oral Session

Findings Suggest Omapro Represents a New Potential Therapy for CML Patients who are Resistant to Two or More TKIs

MELBOURNE, Australia, and MENLO PARK, California U.S.A.

December 09, 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 are resistant or intolerant to two or more tyrosine kinase inhibitors (TKI). New data were presented at the 51st Annual American Society of Hematology Meeting in New Orleans, Louisiana.
At the Oral Session titled “Chronic Myeloid Leukemia - Therapy: New Trends in Management,” Dr. Jorge Cortes, MD, Professor of Medicine and Deputy Chair in the Department of Leukemia at The University of Texas, MD Anderson Cancer Center, and a lead investigator in the study, presented data on behalf of ChemGenex and a team of investigators from leading U.S. and European clinical research centers. Completing his presentation, Dr. Cortes concluded that Omapro represents a new potential therapy for patients with multi-TKI resistant CML.
Data were presented from 89 CML patients: 44 in chronic phase, 25 in accelerated phase and 20 in blast phase. Highlights of the data were:

* Complete hematologic responses (CHR) in 82% of chronic phase patients, median response duration 4.8 months
* Cytogenetic response rate of 27% in chronic phase patients, with major cytogenetic response (MCyR) rate of 23%
* Overall hematologic responses in 80% of accelerated phase patients, with 52% achieving a CHR (median duration 3.1 months).
* Overall hematologic responses in 50% of blast phase patients with 35% achieving a CHR (median duration 2.5 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

“Omapro continues to show that it may provide clinical benefit for CML patients who have developed resistance to currently approved therapies independent of the T315I point mutation” 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 complete this trial.”
About the Study
The study was designed to evaluate the safety and efficacy of subcutaneously (SC) administered omacetaxine in patients who are resistant or intolerant to two or more TKIs. Eligible patients were adult CML patients in chronic, accelerated, or blast disease phase (CP, AP, BP). Patients were given 1.25 mg/m2 SC omacetaxine twice daily for 14 days every 28 days until hematologic response for induction therapy. For maintenance therapy, patients were dosed 1.25 mg/m2 SC omacetaxine twice daily for 7 days every 28 days. Eighty nine patients were described in this presentation (44 CP, 25 AP and 20 BP). The median age was 59 years (20-78) with a median CML disease duration of 72, 92 and 60 months in CP, AP and BP patients, respectively.

About ChemGenex Pharmaceuticals Limited

ChemGenex is an oncology focused biopharmaceutical company developing small molecules with new mechanisms of action to treat malignancies with significant unmet medical needs. A New Drug Application has been accepted by the U.S. Food and Drug Administration and a Marketing Authorisation Application has been validated by the European Medicines Agency for CML patients who have failed imatinib therapy and have the Bcr-Abl T315I mutation. ChemGenex has established a corporate alliance with Hospira to develop and commercialize omacetaxine in Europe, the Middle East and parts of Africa, and is seeking to establish commercial partnerships in the rest of the world. ChemGenex plans to commercialize omacetaxine itself in North America. ChemGenex trades on the Australian Stock Exchange under the symbol "CXS".

Omapro is a trademark of ChemGenex Pharmaceuticals Limited

Contacts

ChemGenex Information
Dr. Greg Collier (CEO and Managing Director)		 Cell Australia +61 419 897501
Cell (USA): +1 650 200 8145
Investor Relations - Australia
Kyahn Williamson
Buchan Consulting		 Tel: +61 (0)3 9866 4722
Cell +61 (0)401 018 828
Investor Relations - USA
Remy Bernarda
Blueprint Life Science Group		 Tel: +1.415.375.3340 x 2022
Cell: +1 415 203 6386

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