Exhibit 15.4

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CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

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We hereby consent to the incorporation by reference in the Registration Statement on Form S-8 (File No. 333-255250) of Adagene Inc. of our report dated April 26, 2022 relating to the financial statements, which appears in this Form 20-F.

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/s/PricewaterhouseCoopers Zhong Tian LLP

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Shanghai, the People’s Republic of China

April 26, 2022