(IFSO) 13th World Congress

LEXINGTON, Mass., September 19, 2008 – GI Dynamics, a medical device company pioneering the development of new approaches to treating metabolic disorders, today announced that new data regarding EndoBarrier™, its novel, noninvasive device currently in clinical trials to treat obesity and type 2 diabetes, will be presented at the International Federation for Surgery of Obesity and Metabolic Disorders (IFSO) 13th World Congress in Buenos Aires, Argentina.

The oral presentation, entitled “A Multi-Center Efficacy Study of the EndoBarrier™ for Pre-Surgical Weight Loss,” will be presented by Ruben Schouten, M.D., Department of General Surgery, Medical University Centre Maastricht, the Netherlands, on Friday, September 26, 2008 at 8:00 a.m. (ART)/7:00 a.m. (EDT).

“We look forward to participating in the IFSO 13th World Congress,” stated Stuart A. Randle, chief executive officer of GI Dynamics. “Obesity has reached global epidemic proportions, and while approved surgical treatment options are benefitting many patients, there exists a significant unmet need for a safe and effective, non-surgical treatment option for the 99% of qualified, clinically obese patients that do not pursue bariatric surgery. We look forward to discussing this promising data with the EndoBarrier Gastrointestinal Liner at the conference.”

About GI Dynamics

GI Dynamics, a clinical-stage medical device company, is pioneering the development of new, noninvasive approaches to treat obesity, type 2 diabetes and related metabolic diseases. The Company’s patented EndoBarrier™ technology is designed to deliver immediate metabolic control by modifying metabolic pathways. GI Dynamics has developed the EndoBarrier™ Gastrointestinal Liner, an orally delivered, removable device that lines a portion of the small intestine, resulting in weight loss and improved glycemic control. Based in Lexington, Massachusetts and founded in 2003, GI Dynamics is backed by top-tier investors including Advanced Technology Ventures, Catalyst Health Ventures, Cutlass Capital, Domain Associates, Johnson & Johnson Development Corporation and Polaris Venture Partners. For more information, visit GI Dynamics online at www.gidynamics.com.