Adagene : Anti-CTLA-4 Candidates Overview

Disclaimer and Cautionary Note on Forward-Looking Statements

The following presentation has been prepared by Adagene Inc. ("Adagene" or the "Company") solely for informational purposes and should not be construed to be, directly or indirectly, in whole or in part, an offer to buy or sell and/or an invitation and/or a recommendation and/or a solicitation of an offer to buy or sell any security or instrument or to participate in any investment or trading strategy, nor shall any part of it form the basis of, or be relied on in connection with, any contract or investment decision in relation to any securities or otherwise. This presentation does not contain all relevant information relating to the Company or its securities, particularly with respect to the risks and special considerations involved with an investment in the securities of the Company. Nothing contained in this document shall be relied upon as a promise or representation as to the past or future performance of the Company. Past performance does not guarantee or predict future performance. You acknowledge that any assessment of the Company that may be made by you will be independent of this document and that you will be solely responsible for your own assessment of the market and the market position of the Company and that you will conduct your own analysis and be solely responsible for forming your own view of the potential future performance of the business of the Company.

This document contains certain statements that constitute forward-looking statements within the meaning of Section 27A of the Securities Act of 1953, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended, with respect to the Company's future financial or business performance, anticipated clinical activities and development, strategies or expectations. These statements typically contain words such as "believe," "may," "will," "could," "expects" and "anticipates" and words of similar import. Any statement in this document that is not a statement of historical fact is a forward-looking statement and involves known and unknown risks, uncertainties and other factors which may cause the Company's actual results, performance or achievements to be materially different from any future results, performances or achievements expressed or implied by such forward-looking statements. Such forward-looking statements including statements regarding the potential implications of clinical data for patients, and Adagene's advancement of, and anticipated clinical activities, clinical development, regulatory milestones, and commercialization of its product candidates. Actual results may differ materially from those indicated in the forward-looking statements as a result of various important factors, including but not limited to Adagene's ability to demonstrate the safety and efficacy of its drug candidates; the clinical results for its drug candidates, which may not support further development or regulatory approval; the content and timing of decisions made by the relevant regulatory authorities regarding regulatory approval of Adagene's drug candidates; Adagene's ability to achieve commercial success for its drug candidates, if approved; Adagene's ability to obtain and maintain protection of intellectual property for its technology and drugs; Adagene's reliance on third parties to conduct drug development, manufacturing and other services; Adagene's limited operating history and Adagene's ability to obtain additional funding for operations and to complete the development and commercialization of its drug candidates; Adagene's ability to enter into additional collaboration agreements beyond its existing strategic partnerships or collaborations, and the impact of the COVID-19 pandemic on Adagene's clinical development, commercial and other operations, as well as those risks more fully discussed in the "Risk Factors" section in Adagene's filings with the U.S. Securities and Exchange Commission. There can be no assurance that the results and events contemplated by the forward-looking statements contained herein will in fact occur. None of the future projections, expectations, estimates or prospects in this document should be taken as forecasts or promises nor should they be taken as implying any indication, assurance or guarantee that the assumptions on which such future projections, expectations, estimates or prospects have been prepared are correct or exhaustive or, in the case of assumptions, fully stated in the document. The Company also cautions that forward-looking statements are subject to numerous assumptions, risks and uncertainties, which change over time and which may be beyond the Company's control.

This presentation concerns product candidates that are or have been under clinical investigation and which have not yet been approved for marketing by the U.S. Food and Drug Administration, European Medicines Agency, The China National Medical Products Administration, or other foreign regulatory authorities. These product candidates are currently limited by U.S. Federal law to investigational use, and no representations are made as to their safety or effectiveness for the purposes for which they are being investigated.

The information that can be accessed through the hyperlinks included in this presentation is not incorporated by reference into this presentation, and you should not consider such information to be part of this presentation.

This document speaks as of July 7, 2023. Neither the delivery of this document nor any further discussions of the Company with any of the recipients shall, under any circumstances, create any implication that there has been no change in the affairs of the Company since that date. Adagene undertakes no obligation to publicly update or revise any forward-looking statements, whether as a result of new information, future events or otherwise, except as may be required by law.

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Adagene Product Candidates are Focused on Unleashing the Potential of Anti-CTLA-4 Therapy by Enhancing the Therapeutic Index (TI)

• Two unique anti-CTLA-4 candidates in phase 1b/2 studies:
• • ADG116 NEObody™ targets a unique binding site
  • ADG126 SAFEbody® is masked version of ADG116
  • Dose escalation completed for both as monotherapy and in combination with anti-PD-1
  • Dose expansion ongoing with anti-PD-1 therapies in targeted tumors, including MSS CRC
  • Roche sponsoring & conducting randomized clinical trial in 1L HCC of ADG126 + atezolizumab + bevacizumab
• Both ADG116 and ADG126 in combination with anti-PD-1 agents demonstrated fast and robust clinical responses while maintaining superior safety profiles
• • Efficacy shown in both PD-1 naïve and PD-1 resistant patients, as well as cold tumors (MSS CRC)
• Collaborations validate SAFEbody masking technology
• • Sanofi and Exelixis technology licensing agreements
  • Adagene eligible to receive ≥$2.5B in potential milestones

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