Exhibit 99.1

                                        CHEMGENEX
                                    PHARMACEUTICALS

FOR IMMEDIATE RELEASE
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CHEMGENEX APPOINTS TWO                                    EXPERIENCED DIRECTORS
     TO BOARD

MELBOURNE, AUSTRALIA, AND MENLO PARK, CALIFORNIA U.S.A. (July 28, 2005):
ChemGenex Pharmaceuticals Limited (ASX: CXS; NASDAQ: CXSP), based in Melbourne,
Australia and Menlo Park, CA, USA, is pleased to announce the appointment of Mr
Patrick Burns and Mr Peter Bradfield to its Board of Directors effective
immediately.

Mr Burns is a U.S.-based biotechnology executive and director with a strong
background in venture capital. Mr Burns is currently a Director of the
Australian biotechnology company Progen Industries Limited, which specializes in
the discovery and development of small molecule-based cancer therapeutics, a
Director of firmView, a New York City-based software company, a Director of
Euclid Systems Corp, an eye care company and StablEyes, Inc a biotechnology
company in the eye care field and a Senior Advisor to Pharmalab, an Australian
pharmaceutical manufacturing company. Mr Burns has previously been a Director of
Synbiotics Corp, which specializes in animal health care. Prior to his
twenty-five year career in venture capital Mr Burns practiced law in New York
with Milbank, Tweed, Hadley & McCloy.

Mr Burns received his Bachelors degree from Dartmouth College and attained a LLB
from Harvard Law School.

"ChemGenex is a very promising biotech company with a strong portfolio of
drugs," said Mr Burns. "I look forward to working with the Company and its Board
of Directors."

Mr Bradfield has an outstanding record as an executive and director of
Australian and international companies. He is a former CEO of Energy Resources
of Australia Limited and former CEO and Managing Director of the Elders Mining
Group of companies. Mr Bradfield is the Managing Director of a boutique
consultancy that offers strategic marketing and development advice to a range of
Australian and international clients. In addition to an outstanding corporate
career, Mr Bradfield has substantial experience in the management of high
technology programs. He is a former Director of Australia's leading research
organization, the CSIRO and has served on the Boards of a number of Cooperative
Research Centres.

Mr Bradfield received his law degree from the University of Melbourne and is a
Fellow of the Australian Institute of Company Directors.

"ChemGenex is clearly one of the leading Australian biotechnology companies,
with a demonstrated ability to implement deals and alliances. I am excited by
the potential for growth in the company and look forward to contributing as a
Director" said Mr Bradfield.






ChemGenex Appoints Two Experienced Directors To Board

PAGE 2 OF 2
"We are delighted that both Patrick and Peter will bring their substantial
experience to ChemGenex," said Dr Greg Collier, Chief Executive Officer and
Managing Director. "Patrick and Peter possess unique insight into the biotech
and high-tech industries and have a wealth of experience in public companies in
the U.S. and Australia.

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 2 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" and the NASDAQ exchange under the symbol "CXSP".



Contacts

                                                                 
Dr. Greg Collier (CEO and Managing Director)         Australia         +61 3 5227 2752
                                                     USA               (650) 474-9800 ext 103
Dr. Dennis Brown (President and Director)            USA               (650) 474-9800 ext 108
                                                     Australia         +61 3 5227 2703
Mr Hershel Berry (Investor Relations)                USA               (415) 392-3310



SAFE HARBOR STATEMENT

Certain statements made herein that use the words "estimate," `project,"
"intend," "expect," "believe," and similar expressions are intended to identify
forward-looking statements within the meaning of the US Private Securities
Litigation Reform Act of 1995. These forward-looking statements involve known
and unknown risks and uncertainties which could cause the actual results,
performance or achievements of the company to be materially different from those
which may be expressed or implied by such statements, including, among others,
risks or uncertainties associated with the development of the company's
technology, the ability to successfully market products in the clinical
pipeline, the ability to advance promising therapeutics through clinical trials,
the ability to establish our fully integrated technologies, the ability to enter
into additional collaborations and strategic alliances and expand current
collaborations and obtain milestone payments, the suitability of internally
discovered genes for drug development , the ability of the company to meet its
financial requirements, the ability of the company to protect its proprietary
technology, potential limitations on the company's technology, the market for
the company's products, government regulation in Australia and the United
States, changes in tax and other laws, changes in competition and the loss of
key personnel. These statements are based on our management's current
expectations and are subject to a number of uncertainties that could change the
results described in the forward-looking statements. Investors should be aware
that there are no assurances that results will not differ from those projected.

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PO Box 1069, Grovedale Victoria 3216, Australia    +61 3 5227 2752          +61 3 5227 1322
                               chemgenex@chemgenex.com     79 000 248 304