Gelesis : Third Quarter 2022 Investor Presentation

Makers of

Third Quarter 2022 Results

November 14, 2022

Forward Looking Statements

Certain statements, estimates, targets and projections in this press release may constitute "forward-looking statements" within the meaning of the federal securities laws. The words "anticipate," "believe," continue," "could," "estimate," "expect," "intend," "may," "might," "plan," "possible," "potential," "predict," "project," "should," "strive," "would" and similar expressions may identify forward-looking statements, but the absence of these words does not mean that statement is not forward looking. Forward-looking statements are predictions, projections and other statements about future events that are based on current expectations and assumptions and, as a result, are subject to risks and uncertainties. Forward-looking statements include, but are not limited to, statements regarding Gelesis' or its management team's expectations, hopes, beliefs, intentions or strategies regarding the future, including those relating to Gelesis' expected operating and financial performance and market

opportunities. In addition, any statements that refer to guidance, projections, forecasts, or other characterizations of future events or circumstances, including any underlying assumptions, are forward- looking statements. Forward-looking statements speak only as of the date they are made. Readers are cautioned not to put undue reliance on forward-looking statements, and Gelesis assumes no obligation and does not intend to update or revise these forward-looking statements, whether as a result of new information, future events, or otherwise. Gelesis gives no assurance that any expectations set forth in this press release will be achieved. Various risks and uncertainties (some of which are beyond Gelesis' control) or other factors could cause actual future results, performance or events to differ materially from those described herein. Some of the factors that may impact future results and performance may include, without limitation: (i) the ability of Gelesis to raise financing, if and when needed and/or to issue or sell common stock pursuant to our committed equity financing agreement; (ii) the ability of Gelesis to continue as a going concern; (iii) Gelesis' ability to achieve and maintain widespread market acceptance of Plenity; (iv) the impact of current and future applicable laws and regulations and Gelesis' ability to comply with such laws and regulations; (v) Gelesis' ability to produce adequate supply of Plenity, including Gelesis' ability to continue to invest in manufacturing capacity and to build additional manufacturing sites; (vi) the development of the telehealth market and regulations related to remote healthcare; (vii) global economic, political and social conditions and uncertainties in the markets that Gelesis serves, including risks and uncertainties caused by the COVID-19 pandemic or other natural or man-made disasters; (viii) Gelesis' ability to enter into strategic collaborations, to acquire businesses or products or form strategic alliances and to realize the benefits of such collaborations, acquisitions and alliances; (ix) the level of demand, and willingness of potential members to pay out-of-pocket for, Plenity; (x) the ability of Gelesis to enforce its intellectual property rights and proprietary technology ; (xi) the risk that a third-party's activities, including with respect to third parties that Gelesis has granted out licenses to or granted limited exclusive or non-exclusive commercial rights, may overlap or interfere with the commercialization of Plenity; (xii) Gelesis' ability to successfully develop and expand its operations and manufacturing and to effectively manage such growth; (xiii) Gelesis' business partners' ability to successfully launch and commercialize Plenity in certain key markets; (xiv) risk relating to the loss of Gelesis' suppliers or distributors, or their inability to provide adequate supply of materials or distribution; (xv) the risk that Gelesis' business partners may experience significant disruptions in their operations; (xvi) Gelesis' ability to retain its senior executive officers and to attract and keep senior management and key scientific and commercial personnel; (xvii) Gelesis' ability to identify and discover additional product candidates and to obtain and maintain regulatory approval for such candidates, including GS200; (xviii) risks related to potential product liability exposure for Plenity, GS200, or other future product candidates; (xix) risks related to adverse publicity in the weight management industry, changes in the perception of Gelesis' brands, and the impact of negative information or inaccurate information about Gelesis on social media; (xx) Gelesis' ability to enhance its brand recognition, increase distribution of Plenity and generate product sales and reduce operating losses going forward; (xxi) the impact of risks associated with economic, financial, political, environmental and social matters and conditions on Gelesis' supply chain, its manufacturing operations and other aspects of its business;

1. Gelesis' ability to accurately forecast revenue and appropriately monitor its associated expenses in the future; (xxiii) Gelesis' ability to compete against other weight management and wellness industry participants or other more effective or more favorably perceived weight management methods, including pharmaceuticals, devices and surgical procedures; (xxiv) foreign currency fluctuations and inflation; (xxv) the risk that Gelesis fails to maintain adequate operational and financial resources or to raise additional capital or generate sufficient cash flows; (xxvi) Gelesis' ability to successfully protect against security breaches and other disruptions to its information technology structure; (xxvii) the ability of Gelesis to maintain its listing on the New York Stock Exchange; (xxviii) failure to realize the anticipated benefits of the business combination; (xxix) our ability to successfully pursue OTC classification for Plenity and the timing for market clearance of such classification; and (xxx) other important factors discussed in the "Risk Factors" section of Gelesis' most recent Annual Report on Form 10-K and in other filings that Gelesis makes with the Securities and Exchange Commission. These filings address other important risks and uncertainties that could cause actual results and events to differ materially from those contained in the forward-looking statements.

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Millions of people

struggle with

excess weight. We aim to transform the

weight

management journey for them.

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Investment Highlights

Clinically Proven

FDA cleared, with a robust efficacy / safety profile.

First of its kind regulated non-systemic approach which is inspired by nature

Largest Addressable Market¹

~150 million adults2 in US alone with excess weight fall within the Plenity label

Affordable and Accessible

Unique Go to Market Strategy delivering affordable solution with easy access, speed & transparency

Proprietary and Protected

Protected by a large portfolio of patents in major geographies

Advanced Pipeline

Clinical Stage Pipeline based on same platform technology can address range of GI-related conditions

Plenity is FDA cleared, regulated as a device, and promoted like a consumer brand.

Currently prescribed as a drug.

Seeking "OTC" classification.

1. Based upon Plenity being indicated to aid in weight management in overweight and obese adults with a Body Mass Index (BMI) of 25-40 kg/m² when used in conjunction with diet and exercise. 4 2. Based on 2013-2014 cycle of NHANES data.

Plenity: FDA Application to Over-the-Counter

Gelesis is preparing an application to the FDA to change the classification of

• Plenity from prescription-only to be available over-the-counter ("OTC")

We believe that Plenity's broad consumer appeal, alongside its strong

• safety and efficacy profile, demonstrated in over 185,000 patients, make now the right time to pursue an OTC pathway with the FDA

The change to OTC could significantly expand access to consumers

• while allowing us to reduce costs associated with member acquisition and the prescription granting process

• On the current trajectory, Plenity could receive clearance from the FDA to market as an OTC product by the middle of 2023

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