Contacts:

Sharon Tetlow diaDexus 408-330-5003 stetlow@diadexus.com

DIADEXUS ANNOUNCES PATENT FOR UTERINE CANCER TEST

Santa Clara, CA - May 23, 2001 - diaDexus today announced that the United States Patent and Trademark Office issued the company a patent covering a method for the diagnosis of uterine and endometrial cancer.

The patent covers a method for detecting uterine and endometrial cancers by detecting either the Human Endometrial Specific Steroid Binding Factor I (hESF I) gene or its gene product. hESF I, also known as Endometrial Cancer Marker I (ECM I), is highly expressed in uterine and endometrial cancers. 

"diaDexus is currently conducting preclinical studies to determine the feasibility of a noninvasive serum test utilizing this patented method," said Robert Wolfert, vice president of diagnostics at diaDexus. "We are hopeful that detecting elevated levels of this protein will prove to be an effective tool in the early diagnosis of uterine and endometrial cancer."

The American Cancer Society¹ estimates that 36,100 new cases of uterine cancer will be diagnosed in 2001, and that 6,500 women will die of the disease this year. Early detection is the most critical aspect in significantly increasing the survival and well-being of cancer patients. If caught in its early stages, researchers estimate that approximately 95% of uterine cancer patients can be cured with surgery. There are currently no adequate diagnostic tests to effectively detect this disease in its early stages. 

"This is the first of our cancer patents to issue," said Wolfert. "To date we have filed patent applications covering nearly three thousand other potential cancer markers." 

diaDexus is focused on translating genomic sequence data into novel diagnostic and therapeutic products. diaDexus has utilized genomics and bioinformatics to identify thousands of disease-associated molecular targets. Currently diaDexus has two diagnostic product candidates in late-stage preclinical development.

diaDexus is located in Santa Clara, California. For more information, please visit the diaDexus Web site at www.diadexus.com.

1. American Cancer Society Facts and Figures 2000