Astria Therapeutics : Corporate Presentation

Corporate Presentation

January 2022

Forward Looking Statements

This presentation and various remarks we make during this presentation contain forward-looking statements of Astria Therapeutics, Inc. ("Astria," the "Company," "we", "our" or "us") within the meaning of applicable securities laws and regulations, including statements with respect to: our future expectations, the potential benefits of the merger between the Company and Quellis Biosciences, Inc. (the "Merger"); our cash runway; the potential timing for the filing of an IND for STAR-0215; the status and anticipated plans and timelines for the early stage clinical trials of STAR-0215, including the anticipated timing of the initial results from the Phase 1 clinical trial and that such results may establish clinical proof of concept for STAR-0215; the potential for STAR-0215 being the best-in-class and most patient friendly preventative treatment option for HAE, and its potential attributes and differentiated profile as a potential treatment option for HAE; the potential commercial opportunity for STAR- 0215; advancing a second program; and the Company's broader goal to meet the unmet needs of patients with rare and niche allergic and immunological diseases. We use words such as "aims," "anticipate," "believe," "estimate," "expect," "goals," "hope," "intend," "may," "opportunity," "plan," "predict," "project," "target," "potential," "would," "vision," "can," "could," "should," "continue," and other words and terms of similar meaning to help identify forward-looking statements, although not all forward-looking statements contain these identifying words. Actual results may differ materially from those indicated by such forward-looking statements as a result of various important factors, including risks and uncertainties related to our ability to recognize the anticipated benefits of the Merger; changes in applicable laws or regulations; the possibility that we may be adversely affected by other economic, business, and/or competitive factors, including the COVID-19 pandemic; risks inherent in pharmaceutical research and development, such as: adverse results in our drug discovery, preclinical and clinical development activities, the risk that the results of pre-clinical studies may not be replicated in clinical studies, the risk that we may not be able to enroll sufficient patients in our clinical trials on a timely basis, and the risk that any of our clinical trials may not commence, continue or be completed on time, or at all; decisions made by, and feedback received from, the U.S. FDA and other regulatory authorities, investigational review boards at clinical trial sites and other review bodies with respect to STAR-0215 and any other future development candidates; our ability to manufacture sufficient quantities of drug substance and drug product for STAR-0215 and any other future product candidates on a cost-effective and timely basis; our ability to obtain, maintain and enforce intellectual property rights for STAR-0215 and any other future product candidates; our potential dependence on collaboration partners; competition with respect to STAR-0215 or any of our other future product candidates; the risk that survey results and market research may not be accurate predictors of the commercial landscape for HAE and the anticipated position of STAR-0215 in HAE based on its pre-clinical profile; our ability to manage our cash usage and the possibility of unexpected cash expenditures; our ability to obtain necessary financing to conduct our planned activities and to manage unplanned cash requirements; the risks and uncertainties related to our ability to recognize the benefits of any additional acquisitions, licenses or similar transactions; and general economic and market conditions; as well as the risks and uncertainties discussed in the "Risk Factors" section of our Annual Report on Form 10-K for the period ended December 31, 2020, subsequent Quarterly Reports on Form 10-Q, and in other filings that we may make with the Securities and Exchange Commission. These forward-looking statements should not be relied upon as representing our view as of any date subsequent to the date of this presentation, and we expressly disclaim any obligation to update any forward-looking statements, whether as a result of new information, future events or otherwise, except as required by law.

This presentation contains estimates and other statistical data made by independent parties and by us relating to market size and other data about our industry. This data involves a number of assumptions and limitations, and you are cautioned not to give undue weight to such data and estimates. In addition, projections, assumptions and estimates of our future performance and the future performance of the markets in which we operate are necessarily subject to a high degree of uncertainty and risk.

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Our mission is to bring hope with life-changing therapies to patients and families affected by rare and niche allergic and immunological diseases.

Our name comes from the Greek word for star, and at Astria, patients are the stars that guide us. Their stories inspire us, their successes energize us, and their challenges

give us purpose.

Our stars illuminate our

work, creating an

environment of

transparency and openness that allows us to build trust with our partners and collaborators.

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Investment Highlights

Astria is developing differentiated therapeutics for patients with rare and niche allergic and immunological diseases

Our lead program, STAR-0215, is a monoclonal antibody inhibitor of plasma kallikrein for the preventative treatment of Hereditary Angioedema (HAE)

• Clinically validated mechanism with potential to be the most patient-friendly preventative therapy for HAE
• On track for STAR-0215 IND filing in mid-2022and key initial proof of concept clinical data by year end 2022

Evaluating opportunities to expand our pipeline in allergic and immunological diseases

Experienced management team and Board backed by leading life science investors including top shareholders Perceptive, RA Capital, Fairmount, Cormorant and Venrock

Cash and cash equivalents of $131.8M1 with expected cash runway through 2023 based on current operating plan

18.3M1 total common shares outstanding (common shares and Series X Preferred) on an as-converted basis

1. As of 9/30/2021

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STAR-0215: Our Lead Asset

OUR

LEAD ASSET

STAR-0215

potential to be most

patient-friendly

preventative treatment

option for HAE

OUR

APPROACH

Developing STAR-0215 to

be a long-acting

monoclonal antibody

inhibitor of plasma

kallikrein dosed once every

3 months or longer

OUR NEAR-TERM

VALUE DRIVERS

Opportunity for clinical

proof of concept for differentiated product in Phase 1 with initial results anticipated by year end 2022

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