October 28, 2008

ARYx to Present at the Oppenheimer & Co. 19th Annual Health Care Conference

ARYx Therapeutics, Inc. (NASDAQ:ARYX) today announced that it will present at the Oppenheimer & Co. 19th Annual Health Care Conference in New York, NY. A live webcast of the presentation scheduled for Tuesday, November 4 at 2:40 p.m. Eastern Time may be accessed at the ARYx website http://www.aryx.com. The presentation will be archived for 90 days.

About ARYx Therapeutics, Inc.

ARYx Therapeutics is a biopharmaceutical company focused on developing a portfolio of internally discovered products designed to eliminate known safety issues associated with well-established, commercially successful drugs. ARYx uses its RetroMetabolic Drug Design technology to design structurally unique molecules that retain the efficacy of these original drugs but are metabolized through a potentially safer pathway to avoid specific adverse side effects associated with these compounds. ARYx currently has four products in clinical trials: an oral anticoagulant agent for patients at risk for the formation of dangerous blood clots, ATI-5923; an oral anti-arrhythmic agent for the treatment of atrial fibrillation, ATI-2042; a prokinetic agent for the treatment of various gastrointestinal disorders, ATI-7505; and, an agent for the treatment of schizophrenia and other psychiatric disorders, ATI-9242. Please visit our web site at www.aryx.com for additional information.