A novel vibrating capsule that signals a postprandial feeling of fullness reduced both food and energy intake and lowered weight gain in animal studies, said researchers who are developing it as a more affordable treatment for obesity.
The capsule, called the Vibrating Ingestible BioElectronic Stimulator (VIBES), is the size of a large adult multivitamin pill and is meant to be swallowed before a meal. The VIBES capsule works by stimulating gastric stretch receptors that signal the brain through the vagal nerve and stimulate a sense of satiety.
“Application of mechanoreceptor biology could transform our capacity to help patients suffering from nutritional disorders,” wrote Shriya S. Srinivasan, PhD, at Harvard University, Boston, and her coauthors. Srinivasan, founder and director of the Biohybrid Organs and Neuroprosthetics (BIONIC) Lab, led the team that designed and prototyped the VIBES capsule.
In a pig model, the VIBES activated mechanoreceptors and triggered gastric mucosal receptors, the researchers reported. Across 108 meals, swine treated with VIBES had nearly 40% reduced food intake compared to controls given a sham pill, with no apparent neural adaptation observed.
The research was published online in Science Advances.
Satiety Signaling in Obesity Treatment
Caroline M. Apovian, MD, codirector, Center for Weight Management and Wellness, Brigham and Women’s Hospital, Boston, who was not involved in the study, said the concept of creating the illusion of satiety is not a new one.
She was part of team that showed medically meaningful weight loss at 2 years with a surgically implanted device that intermittently blocked the vagus nerves near the junction of the stomach and esophagus. “So we’ve been aware of the potential of things like this to produce a sense of satiety and weight loss,” she said.
However, Dr. Apovian believed that a capsule such as VIBES faces a number of hurdles before it is widely used in the clinic, even if it is successfully tested on humans.
She pointed to a superabsorbent hydrogel device, Plenity (Gelesis), delivered as three oral capsules that expand with water in the stomach to create a feeling of satiety. While approved by the US Food and Drug Administration (FDA), it is not widely used, she said, as there are “hurdles” for patients to overcome, particularly in obtaining it from the pharmacy.
The VIBES capsule would in theory be acceptable to patients, Apovian said, but they are “overwhelmed by the media attention” on medications such as glucagon-like peptide 1 (GLP-1) receptor agonists, which promise dramatic weight loss, far higher than the sorts of figures VIBES could achieve.
Nevertheless, the capsule could form a part of the obesity treatment armamentarium, with the idea that it could be combined with “an agent that would act more centrally to change the body weight setpoint,” she said.
Allan Geliebter, PhD, professor, department of psychiatry, Icahn School of Medicine at Mount Sinai, New York City, said that the thinking behind the capsule is a “clever, original approach,” but he is personally skeptical that people will take them.
“It’s the largest possible capsule that’s on the market today that is approved by the FDA for swallowing,” he said, and people “have to assume it’s going to come out the other end.”
“I think it will,” Dr. Geliebter added, “but if you’re taking at least two of these a day, what’s the guarantee one won’t get stuck along the ride?”
And when it does come out, “maybe it will be visible, maybe not,” but either way, “I can see people being anxious.”
He agreed with Dr. Apovian that the arrival of GLP-1 agonists has made obesity “a tough market to compete in right now,” although he noted that the drugs “do have side effects, and not everybody tolerates them.”