News

GI Dynamics, Inc. Reports on Progress of the ENDO Trial

LEXINGTON, Massachusetts & SYDNEY, Australia – 25 April 2013 – GI Dynamics, Inc. (ASX: GID) today announced an update on the status of the ENDO Trial, its U.S. multi-center, pivotal clinical trial of EndoBarrier® for the treatment of patients who have uncontrolled type 2 diabetes and are obese.

“We are very pleased with the quality of the clinical sites and the enthusiasm of the physicians and clinical teams assembled for the ENDO trial,” stated Stuart A. Randle, president and chief executive officer, GI Dynamics, Inc. “We are still in the early stages of rollout and look forward to additional sites coming onboard this year and initiating screening and enrollment in the trial.”

To date, seven sites are actively enrolling subjects:

• Beth Israel Medical Center (New York City)

• Billings Clinic (Billings, Mont.)

• MedStar Health Research Institute (Hyattsville, Md.)

• Tulane University Health Science Center (New Orleans, La.)

• University of Alabama at Birmingham (Birmingham, Ala.)

• University of Colorado – Denver (Denver, Colo.)

• University of Texas Southwestern Medical Center (Dallas, Texas)

The ENDO Trial will enroll approximately 500 patients at up to 25 sites across the United States. Eligible patients should be between the ages of 21 and 65, have a body mass index between 30 and 50, have uncontrolled type 2 diabetes and currently use metformin, a sulfonylurea, or a combination of both, but unable to achieve adequate glycemic control. More information about the ENDO Trial can be found by calling 1-888-9STUDY9 (1-888-978-8399) or by visiting www.endobarriertrial.com.

About EndoBarrier

EndoBarrier is a thin, flexible, tube-shaped liner that forms a physical barrier between food and a portion of the wall of the intestine. In 12 clinical studies conducted outside the United States and one conducted in the United States, with more than 500 patients, EndoBarrier has been tested in similar patient populations. EndoBarrier received CE Mark approval in 2010, and approval by the Therapeutic Goods Administration in Australia in 2011 for the treatment of type 2 diabetes and/or obesity for up to 12 months. EndoBarrier is now pursuing commercial status in the United States. The first step in this process is a successful completion of the ENDO Trial. The device was developed by GI Dynamics, Inc., based in Lexington, Mass. More information about the company may be found at www.gidynamics.com.

About the ENDO Trial

The ENDO Trial is a randomized, double-blind, sham controlled, multi-center trial that is expected to enroll approximately 500 people living with uncontrolled diabetes and obesity who meet specific enrollment criteria at up to 25 sites in the United States. The trial is designed to assess improvements in diabetes over a treatment period of up to 12 months. The primary endpoint of the trial is improvement in HbA1c (a key blood sugar measure for diabetes); secondary measures include weight loss and improvement in select cardiovascular risk factors, such as cholesterol.

About GI Dynamics

GI Dynamics, Inc. (ASX: GID) is the developer and marketer of EndoBarrier®, a breakthrough device that represents an entirely new class of non-surgical, non-pharmaceutical therapy for the treatment of type 2 diabetes and/or obesity. EndoBarrier is approved and commercially available in multiple countries outside the U.S.; and GI Dynamics is conducting a pivotal clinical trial of EndoBarrier in the U.S. for the treatment of patients who have uncontrolled type 2 diabetes and are obese. Founded in 2003, GI Dynamics is headquartered in Lexington, Massachusetts. For more information, please visit www.gidynamics.com.

Forward-Looking Statements

This announcement contains or may contain forward-looking statements that are based on management’s beliefs, assumptions and expectations and on information currently available to management. All statements that address operating performance, events or developments that we expect or anticipate will occur in the future are forward-looking statements, including without limitation our expectations with respect to our ability to commercialize our EndoBarrier® including our estimates of potential revenues, costs, profitability and financial performance; our ability to develop and commercialize new products including our ability to obtain reimbursement for our products; our expectations with respect to our clinical trials, including enrollment in or completion of our clinical trials and our associated regulatory submissions and approvals; our expectations with respect to the integrity or capabilities of our intellectual property position. Management believes that these forward-looking statements are reasonable as and when made. You should not place undue reliance on forward-looking statements because they speak only as of the date when made. GI Dynamics does not assume any obligation to publicly update or revise any forward-looking statements, whether as a result of new information, future events or otherwise. GI Dynamics may not actually achieve the plans, projections or expectations disclosed in forward-looking statements, and actual results, developments or events could differ materially from those disclosed in the forward-looking statements. Forward-looking statements are subject to a number of risks and uncertainties, described in “Risk Factors” in our Prospectus lodged with the Australian Securities & Investments Commission on 3 August 2011.

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