Contacts:

Sharon Tetlow diaDexus, Inc. (650) 246-6400

DIADEXUS PRESENTS AT RODMAN & RENSHAW TECHVEST GLOBAL HEALTHCARE CONFERENCE

South San Francisco, CA - May 10, 2004 - diaDexus, Inc., today announced its Chief Executive Officer, Patrick Plewman, will present on May 14, 2004 at 10:20 a.m. at the Rodman & Renshaw Techvest Global Healthcare Conference, to be held at Claridge's Hotel in London.

Mr. Plewman will provide an update on the company's FDA approved PLAC® test. The PLAC test measures levels of lipoprotein associated phospholipase A2 (Lp-PLA2) and high levels of Lp-PLA2 have been shown to be associated with elevated risk of heart attack. In addition, Mr. Plewman will review data presented at the 5th Annual Conference on Arteriosclerosis, Thrombosis and Vascular Biology showing that elevated levels of Lp-PLA2 are significantly associated with increased risk of stroke.

Mr. Plewman will also discuss the Company's advanced cancer diagnostic pipeline. diaDexus has focused its discovery entirely upon markers for early detection of cancer and has several development candidates in clinical trials. "One area of focus for us is the detection of ovarian, colon and breast cancers," said Plewman. "These cancers still have enormous unmet clinical need in terms of detection and treatment. Ovarian cancer, for example, is typically diagnosed after it has spread, when the cure rate is quite low. If we can detect ovarian cancer early in the course of the disease we could have a significant impact on treatment and survival."

About diaDexus
diaDexus, Inc., a privately held biotechnology company, based in South San Francisco, Calif., is focused on the discovery, development and commercialization of novel, patent-protected diagnostic and therapeutic products with high clinical value. More information about the company may be found at www.diaDexus.com. For information on the PLAC test, please see www.plactest.com.