Perspective from Caroline Apovian, MD
April 17, 2019
3 min read

FDA approves hydrogel pill for overweight, obesity

Perspective from Caroline Apovian, MD
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The FDA on Tuesday approved an oral hydrogel therapy that induces feelings of fullness without adding calories for adults with overweight and obesity, according to a press release from Gelesis.

The oral capsule, (Plenity, Gelesis100), a first-in-class hydrogel matrix containing cellulose and citric acid, is the first treatment FDA approved for adults with a BMI of at least 25 kg/m², with or without comorbidities. There is no restriction on how long Gelesis100 can be used to assist in weight management, according to the release.

“This FDA clearance is a major milestone for the Gelesis team and our technology, and we are thrilled to be able to bring this new prescription product to the millions of people looking for a safe, validated and convenient treatment option to manage their weight without surgery or stimulants,” Yishai Zohar, founder and chief executive officer of Gelesis, said in the release. “With Plenity, Gelesis is introducing a completely new approach with a unique mechanism of action to aid in weight management, with efficacy and safety supported by positive data from large clinical studies.”

Gelesis100 is made by cross-linking cellulose and citric acid to create a three-dimensional hydrogel matrix, according to the company. Capsules are taken with water before lunch and dinner.

“The capsules release thousands of non-aggregating particles that rapidly absorb water in the stomach, creating small individual gel pieces with the elasticity of plant-based foods without caloric value,” the release states. “The gel pieces increase the volume and elasticity of the stomach and small intestine contents, contributing to a feeling of fullness and inducing weight loss. This novel, non-stimulant and non-systemic treatment has been shown in clinical studies to be effective, safe and well-tolerated.”

In a study published in January in Obesity, researchers found that consistent administration of Gelesis100 can double the odds for meaningful weight loss in adults with overweight or obesity compared with lifestyle modifications alone. As Endocrine Today previously reported, in a 24-week, randomized, double-blind, placebo-controlled trial, more than half of the Gelesis100 cohort lost at least 5% of baseline body weight (59%) compared with 42% of those in the placebo group. In addition, weight loss of 10% or more was achieved by 27% of the Gelesis100 group compared with 15% of the placebo group. Participants in the Gelesis100 cohort group were twice as likely to reach weight loss of 5% (OR = 2; P = .0008), 7.5% (OR = 2.1; P = .0017) and 10% (OR = 2.1; P = .0107) compared with placebo. Weight loss was maintained in a 48-week extension trial, according to researchers.


Among participants with prediabetes (fasting plasma glucose 100 mg/dL) or drug-naive type 2 diabetes (FPG 126 mg/dL) who took Gelesis100, 53% lost at least 7.5% of baseline body weight and 44% surpassed 10%. One-quarter of similar participants in the placebo group achieved 7.5% weight loss and 14% reached 10% weight loss. Ultimately, participants with prediabetes or drug-naive type 2 diabetes were 6.1 times more likely to reach 10% weight loss than their placebo group counterparts.

Gelesis100 is contraindicated in patients who are pregnant or are allergic to cellulose, citric acid, sodium stearyl fumarate, gelatin or titanium oxide, and it may alter the absorption of medications, according to the company. The most commonly reported adverse events across trials were gastrointestinal.

Gelesis plans to initiate a targeted U.S. launch of the drug in the second half of 2019 and anticipates treatment will be broadly available by prescription in the U.S. in 2020, according to the release. – by Regina Schaffer

Disclosures: Zohar is founder and chief executive officer of Gelesis.