The Gelesis team includes proven entrepreneurs and leaders in obesity & metabolism, healthcare and commercialization


Yishai Zohar - Chief Executive Officer & Founder

A seasoned entrepreneur, Mr. Zohar has over 25 years’ experience in the development of industry innovating companies. Mr. Zohar is the Founder, Chief Executive Officer and a Board of Directors member of Gelesis Inc., a Boston-based biotechnology company developing a proprietary hydrogel platform designed to leverage mechanobiology along the GI tract to potentially alter the course of chronic diseases including obesity, NAFLD/NASH and inflammatory bowel disease

Zohar led the company from formation and initial discovery as a co-inventor and shepherded the company and product through clinical studies and a landmark FDA clearance of lead product PLENITY™ as an aid for weight management. PLENITY is the first and only FDA-regulated treatment cleared for use by all adults with excess weight (BMI between 25-40 kg/m2) with or without the presence of comorbidities. Prior to founding Gelesis, Mr. Zohar was a Co-Founder of PureTech Health (PRTC.L), a biopharma company developing groundbreaking therapeutics that target the Brain-Immune-Gut axis. In his role at PureTech he led the obesity/GI initiative which engaged leading experts to look at a broad landscape of technologies and approaches. This initiative led to the formation of Gelesis. Zohar has a degree in Business Administration from the College of Management Academic Studies (COMAS) in Tel Aviv and was an air force pilot ranked Captain in the Israeli Defense Forces.

David Pass, Pharm.D. – Chief Operating Officer and Head of Commercial

Dr. Pass joins Gelesis with more than 20 years of commercial expertise across multiple therapeutic areas with a focus on diabetes and metabolics.

Dr. Pass gained a broad range of commercial experience from his time with Johnson & Johnson, and Bristol-Myers Squibb Most recently, Dr. Pass served as Vice President of Marketing at Boehringer Ingelheim (BI) for Diabetes, where he built a billion-dollar franchise. In this role, Dr. Pass also led the BI alliance with Eli Lilly & Company to develop and commercialize a portfolio of diabetes compounds in mid- and late-stage development. David received both his B.S. Pharmacy and Doctor of Pharmacy degrees from Philadelphia College of Pharmacy and Science. He enjoys many interests outside work including cycling, snowboarding, golf and woodworking.

Alessandro Sannino, Ph.D. - Co-inventor & Lead Project Scientist

Dr. Alessandro Sannino is a co-inventor of the GS100 technology, is Professor of Polymer Science and Technology and the director of the Bioslabs at the University of Salento.
Dr. Sannino is responsible for the Life Science division of the Puglia District of Technology and adjunct faculty at the Massachusetts Institute of Technology (MIT). He is also an advisor to the National Institute of Health, of the Italian Ministry of Health (Italian equivalent to the FDA). Dr. Sannino’s research activity is focused on macromolecular hydrogels, polymer microstructure modifications, tissue engineering constructs and cell-material interactions, has published over 100 scientific papers on these topics. He received his PhD at University of Naples and University of Washington on polymer technology, and did a post-doctoral fellowship at MIT.

Joy Bauer, MS, RDN, CDN – Chief Nutrition Officer of Plenity

Joy Bauer, MS, RDN, CDN, is one of the nation’s leading health authorities. She is a well-known TV and media personality and a #1 New York Times bestselling author with 14 bestsellers to her credit. Joy is also the creator of and the official nutritionist for the New York City Ballet.

In the earlier part of her career, Joy was the Director of Nutrition and Fitness for the Department of Pediatric Cardiology at Mount Sinai Medical Center in New York City, as well as the clinical dietitian for their neurosurgical team. One of Joy’s most rewarding experiences was creating and implementing “Heart Smart Kids,” a health program for underserved children living in Harlem. Prior to making the jump to media, she taught Anatomy & Physiology and Sports Nutrition at NYU’s School of Continuing Education, as she worked to build what would soon become the largest private nutrition center in the country.

Passionate about delivering scientifically sound, realistic information to millions of Americans, Joy has received countless awards including the National Media Excellence Award from two of the most esteemed organizations, the Academy of Nutrition and Dietetics and the American Society of Nutrition Science.

When she’s not dishing out health info or sharing tasty recipes on TV, you’ll find Joy making a mess in her kitchen or spending quality time with her husband, three kids, and fur-baby, Gatsby.

See our scientific advisors