Contacts:

Patrick Plewman diaDexus, Inc. (650) 246-6400

Carolyn Bumgardner Wang WeissComm Partners (415) 362-5018 x123 carolyn@weisscommpartners.com

DIADEXUS TO PRESENT AT RODMAN & RENSHAW TECHVEST 6th ANNUAL HEALTHCARE CONFERENCE

South San Francisco, CA - October 25, 2004 - diaDexus, Inc., today announced that Patrick Plewman, President and Chief Executive Officer of diaDexus, will present a corporate overview at the Rodman & Renshaw Techvest 6th Annual Healthcare Conference on Wednesday, October 27, 2004 at 9:00 a.m. This event is being held at the Waldorf-Astoria in New York.

About diaDexus
diaDexus, Inc., a privately held biotechnology company, 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. The PLACT test, developed by diaDexus, Inc., is a blood test cleared by the U.S. Food and Drug Administration to aid in the prediction of an individual's risk for a coronary event, in conjunction with clinical evaluation and patient risk assessment. The PLAC test is currently available through laboratories nationwide. For more information about the PLAC test visit www.plactest.com. More information about the company may be found at www.diaDexus.com.