Paul M. Stein, PhD, Onciomed, Irvine, California, USA, presented results showing substantial loss of weight in pigs after implantation of a novel restrictive bariatric medical device called the Onciomed Gastric Vest System (OGVS). In this animal study the minimally invasive implant device was safe, durable, and highly effective at enabling long-term weight loss with no apparent adverse effects.

In 2013, the American Medical Association declared obesity a disease [http://www.ama-assn.org/ama/pub/news/news/2013/2013-06-18-new-ama-policies-annual-meeting.page]. The incidence of obesity is increasing across the world. By 2020, obesity is expected to affect 672 million individuals, including 149 million in the United States. Obesity currently affects 1 in every 2 adults as well as 1 in 6 children younger than 13 years, and it is the number one cause of type 2 diabetes.

Dietary modifications, exercise, pharmaceuticals, medical devices, and gastric surgery are the most often used approaches to control weight. Patients are frequently not compliant with diet and exercise, and current pharmacological treatments have been associated with some adverse events that decrease adherence. Current devices for the treatment of obesity include balloons and balls that temporarily fill the stomach for 3 to 9 months, and liners or barriers that prevent nutrient absorption for ∼ 9 months. The gastric band, which is delivered laparoscopically, is intended to be long-term treatment but has been found to occasionally slip off. Gastric surgery, although highly effective, is seen as the method of last resort. All gastric surgeries create either a banana shape or a small pouch out of the stomach that produces restrictions leading to less food intake and thus weight loss. Concerns with surgery include the long-term ramifications of losing large portions of the gastrointestinal tract (especially in the young), serious adverse events associated with bleeding and leaks from staple insertions, re-expansion of the stomach throughout time, and the potential for permanent malnutrition.

The OGVS was developed as a long-term medical implant that modifies the stomach into a banana shape, like in gastric surgery, but without removing portions of the stomach or allowing the stomach to re-expand throughout time. The device is designed to work by decreasing caloric intake, increasing satiety via neuro-hormonal responses, and improving gastric emptying. The device is implanted laparoscopically using a procedure that is easy to perform, quick (∼ 40 to 60 minutes), and fully reversible.

Dr. Stein discussed results from a small study in pigs in which 3 received sham procedures and 7 received OGVS implants. The animals were followed for 9 months. Interest in food quickly waned within a week in the implanted animals. After 3 months, body weight in the sham animals increased by 36%, whereas body weight in the implant animals decreased by 21%. There were no postsurgical complications, and all animals remained healthy throughout the study.

At the end of the study, animals receiving implants appeared lean. At necropsy, the internal and external appearance of the abdominal organs appeared normal in both sham and implanted animals. The OGVS was completely encapsulated in a thin sheath of white connective tissue. No tears were present, and no extension of the suture holes was noted. This device needs further study but may be a future option for the treatment of patients with obesity.