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Gelesis announces merger with Capstar Special

Gelesis, a biotherapeutics company advancing biomimetic superabsorbent hydrogels to treat excess weight and metabolic disorders, and Capstar Special Purpose Acquisition Corporation have entered into a definitive business combination agreement. Transaction is expected to provide Gelesis with up to US$376 million of gross proceeds to fund the full commercial launch of Plenity later in 2021 and to expand manufacturing to meet demand.

Gelesis’ proprietary biomimetic superabsorbent hydrogel technology, Plenity, is FDA approved to aid in weight management in adults with excess weight or obesity, when used in conjunction with diet and exercise. Plenity has the broadest BMI range of any prescription weight-management aid to date - over 150 million American adults could be eligible for treatment with Plenity - many of whom did not have a prescription alternative before. Plenity’s unique scientific approach and efficacy, safety and tolerability profile allow Gelesis to bring it to market in a completely new way.


Plenity capsules contain a non-systemic biomimetic hydrogel that is not absorbed but instead acts locally in the gastrointestinal (GI) tract. The capsules are taken with water before meals and are designed to help people feel satisfied with smaller meals. Plenity combines the simplicity and convenience of a consumer product with clinical and scientific validation as well as FDA regulatory clearance as a de novo Class II medical device. In clinical studies, approximately six out of ten adults had clinically meaningful weight loss and those people lost on average, within six months, ten percent of their body weight (about 22lbs). There was no difference in overall side effects compared to placebo. The most common side effects were diarrhoea, distended abdomen, infrequent bowel movements and flatulence.


Plenity is a prescription product with a direct-to-patient approach, giving the consumer the option of going through leading telehealth platform Ro, or through an in-person healthcare provider visit. This makes it easier for consumers to seek free physician evaluation on their own time and their own terms. If prescribed, the product is delivered to the consumer’s home within two days at a transparent cost of IS$98/month or US$1.75 per meal.


Plenity is now available in limited release, and over 48,000 members have begun their weight management journey. During Plenity’s beta launch in October 2020, with limited promotion and without brand awareness marketing, Plenity surpassed all branded prescription weight management products in new monthly members during the month of testing, with high satisfaction ratings, the company stated. Its anticipates the full commercial launch of Plenity later in 2021 and is currently constructing a larger manufacturing facility to meet anticipated demand.


Gelesis’ novel platform technology is inspired by the structural and mechanical properties of raw vegetables. When consumed, the hydrogel forms small solid gel pieces in the stomach consisting of water held by a 3D cellulose structures, similar to raw vegetables. The structures, which have no calories, are homogeneously mixed with the ingested foods, increasing the volume and firmness of that meal while reducing its caloric density. The hydrogel pieces are not absorbed and partially degrade in the large intestine, releasing the water before leaving the body naturally. In clinical trials, this therapeutic approach demonstrated a strong efficacy and safety profile.

“We are delighted to have found such a stellar group of partners and investors as we expand the launch of the first and only FDA-cleared and clinically validated prescription aid for weight management that is available for the broadest range of the population with excess weight, including even those who are overweight without co-morbidities,” said Yishai Zohar, Founder and CEO of Gelesis. “Capstar’s leadership team has a track record of successfully building known brands and tackling fundamental consumer problems across a variety of industries. We look forward to building on the exciting momentum of our beta launch with this partnership and funding, and we are committed to making a meaningful difference in the lives of millions of Americans seeking scientifically proven and convenient options to manage their weight.”

The transaction values the combined company at an implied enterprise value of approximately US$1.0 billion and equity value of approximately US$1.3 billion. The transaction has been unanimously approved by the Boards of Directors of both Gelesis and Capstar. It is expected to close in the fourth quarter of 2021, subject to the satisfaction of certain closing conditions, including a registration statement being declared effective by the US Securities and Exchange Commission and the approval of Capstar shareholders.

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