Dive Brief:

• PureTech's Gelesis affiliate has received De Novo clearance from FDA to market a prescription weight management aid. The edible hydrogel capsule, called Plenity, is meant to create a feeling of fullness in the stomach to treat overweight and obese patients.
• The product's pivotal study showed effectiveness, meeting its primary endpoint with 59% of patients who received the treatment losing at least 5% of their weight, compared to 42% in the placebo group. The treatment also had a favorable safety and tolerability profile.
• Gelesis said it plans to initiate a targeted U.S. launch of the weight loss aid in the second half of 2019 and expects the treatment will be widely available by prescription in the United States in 2020.

Dive Insight:

The Plenity capsule releases thousands of particles that rapidly absorb water and swell in the stomach to create gel pieces with the firmness of plant-based foods but with no caloric value or absorption into the bloodstream. Made by cross-linking cellulose and citric acid, the hydrogel capsules are taken with water before lunch and dinner. The product is considered a medical device because it achieves its purpose through mechanical modes of action.

The product is indicated as an aid in weight management, when combined with diet and exercise, in adults who are overweight or obese and have a body mass index (BMI) of 25 to 40 kg/m2. Obesity typically is defined as having a BMI of 30 kg/m2.

Eligible patients may have comorbidities including hypertension, Type 2 diabetes or dyslipidemia. There is no restriction on how long the treatment can be used.

Analysts at Jefferies said the BMI range is the widest of any FDA-cleared therapy, suggesting up to 150 million U.S. adults may be eligible for the first-in-class treatment. "We assume Gelesis considers a partnership(s) for launch given the large addressable patient population and wide prescriber base, particularly for the fragmented EU market," the analysts said in a research note.

In the company's pivotal clinical study of 436 adults, about six out of 10 patients who received the treatment responded positively, losing an average of 10 percent of their weight (22 pounds) and almost 4 inches from their waists within six months.

Side effects in patients treated with Plenity were similar to those seen in the placebo group, with the most common being fullness, bloating, flatulence and abdominal pain. The most common treatment related adverse events were gastrointestinal disorders in 38% of patients who took the Plenity capsules, compared to 28% in those who received the placebo.

"The most compelling aspects of this approach are its effectiveness, novel mechanism of action and impressive safety data," Ken Fujioka, endocrinology researcher at Scripps Clinic and scientific adviser to Gelesis, said in a press release. "This approach creates another arm in the treatment algorithm of weight management."

Gelesis, co-founded by biopharma company PureTech, is developing a second weight-loss treatment, Gelesis200, a hydrogel for glycemic control in patients with type 2 diabetes and prediabetes. Gelesis said its pipeline also includes potential therapies for non-alcoholic fatty liver disease, non-alcoholic steatohepatitis and inflammatory bowel disease.