Contacts:

Mohan Iyer diaDexus, Inc. Vice President, Business Development diaDexus, Inc. 650-246-6431 miyer@diaDexus.com

DIADEXUS AND THE UNIVERSITY OF MICHIGAN ENTER PROTEOMICS COLLABORATION TO IDENTIFY CANCER DRUG TARGETS AND BIOMARKERS

South San Francisco, CA - September 4, 2002 - diaDexus, Inc. today announced that they have entered into a research agreement with the University of Michigan focused on the use of novel proteomic technologies for the comprehensive analysis of cell surface membrane proteins to identify new drug targets and biomarkers useful for the treatment and diagnosis of cancer.

Under the terms of the multi-year agreement, diaDexus will provide research funding for the program in exchange for the exclusive option to license intellectual property rights for potential therapeutic and diagnostic products. The agreement also provides for milestone and royalty payments from diaDexus to the University of Michigan on products resulting from the research. Financial terms were not disclosed.

The research will be directed by Dr. Samir Hanash, M.D., Ph.D., a professor of pediatrics and communicable diseases in the University of Michigan Medical School. Dr. Hanash's laboratory has developed novel technologies in proteomics and has identified promising protein markers and antigens for the early diagnosis of cancer.

"To date, we have not had effective strategies to deal with the limited quantity of surface membrane proteins and to resolve and identify such proteins," said Dr. Hanash. "Our approach will be to focus on cell surface proteins, a potentially rich source of novel targets and biomarkers. The strategy that we have developed and implemented both enhances the sensitivity of the quantitative analysis of surface proteins and assists subsequent identification of such proteins. We are pleased to work with diaDexus because they are clearly committed to the development of both therapeutic and diagnostic products that will ultimately benefit cancer patients."

The agreement calls for Dr. Hanash's team to comprehensively analyze normal and cancerous primary samples and cell lines using technologies developed to possess the requisite sensitivity to overcome the limitations of current approaches to expression proteomics. Dr. Hanash's team will also provide certain genomic analyses related to new targets and biomarkers.

"We are very excited to work with Dr. Hanash who is among the world's leading experts in the application of proteomic discovery tools to medicine, especially cancer," said Ronald M. Lindsay, Ph.D., Vice President, Research and Development and Chief Scientific Officer of diaDexus. "We believe that his team's novel strategies for analyzing cell membranes will yield new therapeutic targets that may also serve as disease markers. This program will complement both our internal genomics discovery program as well as two external collaborations we have recently established: with Compugen to mine the transcriptome for alternative splice variants and with Beyond Genomics to profile serum and tissue for differentially expressed proteins."

diaDexus, based in South San Francisco, California, is focused on the discovery, development and commercialization of novel, patent protected diagnostic and therapeutic products with high clinical value. diaDexus has utilized genomics and bioinformatics to identify thousands of disease-associated molecular targets. For more information, please visit www.diaDexus.com.

The statements in this press release which are not historical facts or information may be forward-looking statements. These forward-looking statements involve risks and uncertainties that could cause the outcome to be materially different from the outcome described in these forward-looking statements.