• First study of EndoBarrier in adolescents completed at University Children’s Hospital (UCH) in Ljubljana, Slovenia
  • Preliminary data show BMI reduced by 10 percent
  • Acceptable safety profile and improvement in metabolic parameters

BOSTON and SYDNEY — 16 February 2017 — GI Dynamics, Inc. (ASX:GID), a medical device company that has commercialized EndoBarrier in Europe for patients with type 2 diabetes and obesity, today announced that enrollment is complete in the first clinical trial evaluating EndoBarrier in adolescents.  The study was conducted at the University Children’s Hospital (UCH) in Ljubljana, Slovenia.

This investigator-initiated prospective single-arm study was led by Tadej Battelino, MD, PhD, Professor of Pediatrics at UCH, and was designed to determine the efficacy and safety of the EndoBarrier treatment for up to one year in morbidly obese adolescents. Preliminary data show that patients who received the treatment saw an average of 10 percent decrease in body mass index (BMI), metabolic improvements and no serious adverse effects.

“The preliminary data show that treatment with EndoBarrier has the potential to treat prediabetic, severely obese adolescents, especially those with metabolic complications,” said Dr. Battelino. “In this study, relevant weight loss was achieved in most of the subjects, with clinically relevant improvements in metabolic stabilization in prediabetic patients. Our cohort also saw an acceptable safety profile with no serious adverse events.”

Preliminary relevant metrics are reported here:

Reduction at 12 months       /       n = 20
Baseline 12 months Reduction: Mean Reduction: %
BMI (kg/m2) 42.5 38.2 4.3 10%
Waist circumference (cm) 127 116 11 9%
HbA1c 5.3% 5.0% 0.3% 6%
HOMA-IR 5.5 2.8 2.7 49%
Triglycerides (mmol/l) 2.1 1.2 0.9 43%
Systolic Pressure (mmHG) 124 117 7 6%

EndoBarrier demonstrated therapeutic benefit in treating prediabetes, as blood sugar levels (HbA1c) were reduced by 6 percent and BMI was reduced by an average of 10 percent in study subjects. Most notable was the 49% improvement in HOMA-IR (Homeostatic Model Assessment), a critical measure of insulin resistance and beta-cell function. In addition, the study noted clinically significant reductions in triglycerides (43 percent) and systolic blood pressure (6 percent).

EndoBarrier demonstrated an acceptable safety profile, with all study subjects completing treatment to the intended twelve-month implant duration. No devices were removed due to adverse events; there were no serious device-related adverse effects. Some patients reported abdominal discomfort, mild pain, nausea and gastrointestinal issues.

This new data confirms and adds to the preliminary analysis of study subjects at six and twelve months that was previously presented at the European Society for Pediatric Endocrinology (ESPE) conference in Paris.

Obesity and its complications have a significant effect on morbidity and mortality for adolescents. Standard treatment-based diets and cognitive therapy have limited effects. Surgical bariatric procedures are nonreversible and permanently alter certain metabolic functions. The long-term consequences of those alterations in the corporaldevelopment of adolescents are not well known but are a source of great concern.

“Obesity in adolescents has risen to epidemic levels globally with serious individual and public health consequences, and long-term implications that we only have just begun to understand,” said Scott Schorer, GI Dynamics president and CEO.

“This study, in conjunction with many additional investigator-initiated studies around the world, is completing a picture of clinical evidence that further reinforces the broader safety and efficacy profile of EndoBarrier.”

About GI Dynamics

GI Dynamics, Inc. (ASX:GID), is the developer of EndoBarrier, the first endoscopically-delivered device therapy approved for the treatment of type 2 diabetes and obesity. EndoBarrier is approved and commercially available in multiple countries outside the United States. EndoBarrier is not approved for sale in the United States and is limited by federal law to investigational use only in the United States. Founded in 2003, GI Dynamics is headquartered in Boston, Massachusetts. For more information, please visit www.gidynamics.com.

Forward-Looking Statements

This announcement contains forward-looking statements concerning our development and commercialization plans, potential revenues and revenue growth, costs, excess inventory, profitability and financial performance, ability to obtain reimbursement for our products, clinical trials and associated regulatory submissions and approvals, the number and location of commercial centers offering the EndoBarrier, and our intellectual property position. These forward-looking statements are based on GI Dynamics’ management’s current estimates and expectations of future events as of the date of this announcement. Furthermore, the estimates are subject to several risks

and uncertainties that could cause actual results to differ materially and adversely from those indicated in or implied by such forward-looking statements. These risks and uncertainties include but are not limited to, risks associated with the consequences of terminating the ENDO trial and the possibility that future clinical trials will not be successful or confirm earlier results. Further risks are associated with obtaining funding from third parties; the timing and costs of clinical trials; the timing of regulatory submissions; and the timing, receipt and maintenance of regulatory approvals. The timing and amount of other expenses and the timing and extent of third-party reimbursement risks associated with commercial product sales, including product performance, competition, risks related to market acceptance of products, intellectual-property risk; risks related to excess inventory; and risks related to assumptions regarding the size of the available market, the benefits of our products, product pricing, timing of product launches, future financial results and other factors, including those described in our filings with the U.S. Securities and Exchange Commission. Given these uncertainties, one should not place undue reliance on these forward-looking statements. We do not assume any obligation to publicly update or revise any forward-looking statements, whether as a result of new information or future events or otherwise, unless we are required to do so by law.