July 6, 2004

Chiron Acquires Sagres Discovery

For Immediate Release

- Acquisition Deepens Quality of Chiron's R&D Pipeline -

EMERYVILLE, Calif., Jul 6, 2004 /PRNewswire-FirstCall via COMTEX/ -- Chiron Corporation (Nasdaq: CHIR) and Sagres Discovery announced today Chiron has acquired Sagres. Sagres, a privately held company headquartered in Davis, Calif., focuses on the discovery and validation of targets with potential application to the development of cancer therapeutics. Financial terms of the acquisition were not disclosed.

"This is a unique opportunity to advance our goal of building a competitive, balanced pipeline for Chiron," said Kenneth Bair, senior vice president and head of research, Chiron BioPharmaceuticals. "Sagres has a wealth of in vivo validated targets, including kinases and antibodies, that will increase both the quantity and quality of targets available to us for development. With the wealth of targets from Sagres, we expect to be able to maximize the value of our collaboration with Xoma Ltd. and our small molecule drug discovery program for the development and commercialization of new drugs for the treatment of cancer."

"We are delighted to have the technology and drug targets our team has developed over the last several years joined with the resources and talents of Chiron," said Dr. Ali Fattaey, chief scientific officer, Sagres Discovery. "The incredible amount of novel discoveries generated from the Oncogenome(TM) has been changing the way we view gene function and cooperation in cancer development, and is refining how we select targets for cancer drug discovery and development. With Chiron, these discoveries now have a fantastic opportunity to be translated into novel drug candidates, and in time, actual drugs that will benefit cancer patients."

Sagres Discovery technology has created the Oncogenome(TM), a comprehensive assembly of genes that cause cancer. The technology combines gene isolation and in vivo biological validation into one high-throughput process. Through molecular profiling of human disease tissues, clinical relevance is established concurrently with gene discovery and validation. This technology is able to discriminate between those few genetic factors that cause disease (oncogenes and tumor suppressors) and the confounding factors that respond to disease processes. Only genes that cause the cancer phenotype are recovered and downstream effects are specifically excluded.

As a result, the Sagres Discovery approach eliminates significant time- and resource-intensive secondary screening required by most other approaches. This allows Sagres Discovery to advance targets into discovery sooner and with more confidence.

About Chiron
Through its global Blood Testing, Vaccines and BioPharmaceuticals businesses, Chiron Corporation addresses human suffering with more than 50 diverse products to detect, prevent and treat disease worldwide. The company's consistent success has come from its pioneering science, skill in delivering innovations in biotechnology and disciplined business approach. Chiron believes that science has the power to improve people's lives and harnesses that power to transform public health.

This year, Chiron Vaccines celebrates 100 years of advancing medicine with the anniversary of two founding companies. In 1904, Emil von Behring and Achille Sclavo independently started companies in Germany and Italy, respectively, dedicated to the research, development and manufacture of vaccines to protect humanity from infectious disease. As the fifth-largest vaccine manufacturer in the world, Chiron remains dedicated to the legacies of von Behring and Sclavo to prevent disease and develop new vaccines to improve human health globally.


Sagres Discovery
Sagres is a discovery stage company dedicated to understanding the molecular basis of cancer. Sagres Discovery’s technology platform combines the biology of cancer formation in mouse models with the robustness of high-throughput genomic technologies to enable discovery and clinical validation of human cancer genes at unprecedented speed. The Company is assembling the Oncogenome™, one of the most comprehensive sets of oncology targets in the world. Of equal importance, the technology allows for the discrimination between genes that cause disease and those that affect or respond to disease processes. In addition to its own internal drug discovery program, the Company is building its initial product pipeline by selectively using strategic partnerships and collaborations. Sagres is located in Davis, California.


This press release is made as a matter of record, and is not intended, nor should be interpreted, as a recommendation or solicitation to invest in any company or in any Axiom entity.