- Gelesis, a subsidiary of the Boston-based PureTech Health, said it would discuss with regulators submitting its weight loss drug for approval, despite results from a pivotal study showing the treatment missed on one of its two co-primary endpoints.
- Nearly 60% of patients who took Gelesis' oral drug lost 5% or more of body weight, compared to 42% of those treated with placebo, meeting the study's other main objective and giving Gelesis confidence in the treatment's profile.
- The Food and Drug Administration approved several weight loss drugs in recent years, such as Orexigen Therapeutics, Inc.'s Contrave (naltrexone/bupropion), but sales have been slow and a broad market has failed to materialize.
Gelesis designed its drug, called Gelesis100, as a hydrogel capsule taken orally before meals. Particles within the capsule absorb water and swell, boosting the sensation of "fullness."
In the so-called GLOW study, Gelesis tested the drug in 436 adults, randomized to either placebo or a 2.25 g dose of Gelesis100. While results showed treatment with Gelesis100 led to a greater number of patients meeting weight loss targets, the study did not show the desired 3% mean difference in weight loss between Gelesis100 and placebo.
There were no serious adverse events, however, and fewer patients on treatment dropped out compared to placebo. That safety profile could be a major check in Gelesis' favor.
"Based on these results, Gelesis100 could potentially be the treatment we’ve been missing for the patients who need it most," said Frank Greenway, a principal investigator for Gelesis' study. "Current interventional approaches to weight loss are often invasive and/or have serious side effects."
Orexigen's Contrave, for example, comes with a black box warning for suicidal thoughts and behaviors.
Amy Walker, an analyst at Peel Hunt, suggested Geleisis should focus on the drug's risk/benefit profile despite the "disappointment" of missing the second co-primary endpoint, which she blamed on an unexpectedly high placebo response.
"We see strong reasons to believe Gelesis100 could nevertheless obtain FDA approval and good market uptake," she said.
Jefferies analyst Peter Welford was also upbeat, predicting a filing for launch by 2019, based on the product's "clear signs of clinically meaningful efficacy and a clean safety profile."
While Gelesis may be able to get past regulators with the mixed results, carving out a market may be an even harder task should Gelesis100 reach markets.
Gelesis has another drug, dubbed GS200, currently in clinical trials for glyemic control and weight loss in adults, as well as constipation.