ChemGenex Pharmaceuticals Receives European Patent Allowance for Cancer Drug, Quinamed.

MELBOURNE, Australia & MENLO PARK, Calif. -- Covers Use of Quinamed(R) (amonafide dihydrochloride) to Boost the Effect of Common Cancer Therapies

ChemGenex today announced that it received a Notice of Allowance from the European Patent Office (EPO) for its patent application entitled "Compositions Containing Naphthalimide and an Antiproliferative Agent." This patent will cover compositions and methods of use of the company's investigational agent, amonafide (Quinamed(R)), to improve or "chemopotentiate" the anti-cancer effects of common chemotherapeutics, including cisplatin, paclitaxel, vinblastine and camptothecin.

Quinamed(R) is currently undergoing Phase II human clinical testing as a potential treatment for hormone refractory prostate cancer. Although currently approved antiproliferative agents offer therapeutic activity against many forms of cancers, improvements in tumor response rates, duration of response and ultimately patient survival are still sought for these agents. ChemGenex researchers have determined that naphthalimides and analogs of the class of compounds, including Quinamed(R), can potentiate the antitumor effects of chemotherapeutic drugs, in particular, agents affecting the integrity of nucleic acids such as DNA.

"ChemGenex has filed numerous patents covering amonafide compositions, formulations, synthesis and uses," said Greg Collier, Ph.D., chief executive officer of ChemGenex. "This initial patent will provide protection for the longer term use of Quinamed(R) in conjunction with other agents. Other patent applications cover the composition of matter for amonafide dihydrochloride, and for a variety of other amonafide salts created with organic acids."

About ChemGenex Pharmaceuticals Limited (www.chemgenex.com)

ChemGenex Pharmaceuticals is a gene-based pharmaceutical company dedicated to improving the lives of patients by developing therapeutics in the areas of oncology, diabetes, obesity, and depression. ChemGenex currently has two compounds in Phase II clinical trials, Ceflatonin(R) for leukemia and Quinamed(R) for solid tumors, and has a significant portfolio of anti-cancer, diabetes, obesity and depression programs. The company's diabetes and obesity program is partnered with Merck KGaA and the depression program is partnered with Vernalis PLC. ChemGenex currently trades on the Australian Stock Exchange under the symbol "CXS".

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