Adagene (ADAG) 20-F 29 Mar 24 2023 FY Annual report (foreign) Financial data

Document and Entity Information

Document and Entity Information	12 Months Ended
	Dec. 31, 2023 shares
Document and Entity Information
Document Type	20-F
Document Registration Statement	false
Document Annual Report	true
Document Period End Date	Dec. 31, 2023
Document Transition Report	false
Document Shell Company Report	false
Entity File Number	001-39997
Entity Registrant Name	Adagene Inc.
Entity Incorporation, State or Country Code	E9
Entity Address, Address Line One	4F, Building C14, No. 218
Entity Address, Address Line Two	Xinghu Street, Suzhou Industrial Park
Entity Address, City or Town	Suzhou
Entity Address, Postal Zip Code	215123
Entity Address, Country	CN
Entity Common Stock, Shares Outstanding	55,145,839
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
ICFR Auditor Attestation Flag	false
Document Financial Statement Error Correction [Flag]	false
Document Accounting Standard	U.S. GAAP
Entity Shell Company	false
Entity Central Index Key	0001818838
Current Fiscal Year End Date	--12-31
Document Fiscal Period Focus	FY
Document Fiscal Year Focus	2023
Amendment Flag	false
Auditor Name	PricewaterhouseCoopers Zhong Tian LLP
Auditor Firm ID	1424
Auditor Location	Shanghai, the People’s Republic of China
Business Contact
Document and Entity Information
Entity Address, Address Line One	10179 Huennekens Street Suite 103
Entity Address, City or Town	San Diego
Entity Address State Or Province	CA
Contact Personnel Name	Peter Luo
Country Region	86
City Area Code	512
Local Phone Number	87773616
Contact Personnel Email Address	peter_luo@adagene.com
American depositary shares
Document and Entity Information
Trading Symbol	ADAG
Security Exchange Name	NASDAQ
Title of 12(b) Security	American depositary shares
Common Stock [Member]
Document and Entity Information
Security Exchange Name	NASDAQ
No Trading Symbol Flag	true
Title of 12(b) Security	Ordinary shares, par value US$0.0001 per share

CONSOLIDATED BALANCE SHEETS

CONSOLIDATED BALANCE SHEETS - USD ($)	Dec. 31, 2023	Dec. 31, 2022
Current assets:
Cash and cash equivalents	$ 109,934,257	$ 143,758,678
Amounts due from related parties	$ 222,027	$ 619,432
Other Receivable, after Allowance for Credit Loss, Current, Related Party, Type [Extensible Enumeration]	us-gaap:RelatedPartyMember	us-gaap:RelatedPartyMember
Prepayments and other current assets	$ 3,287,445	$ 4,937,323
Total current assets	113,443,729	149,315,433
Property, equipment and software, net	1,835,121	2,782,963
Operating lease right-of-use assets	365,103	191,877
Other non-current assets	84,885	109,572
TOTAL ASSETS	115,728,838	152,399,845
Current liabilities:
Accounts payable	3,093,752	3,666,124
Contract liabilities		15,107,276
Amounts due to related parties	$ 16,714,326	$ 19,323,337
Other Liability, Current, Related Party, Type [Extensible Enumeration]	us-gaap:RelatedPartyMember	us-gaap:RelatedPartyMember
Accruals and other current liabilities	$ 3,001,508	$ 3,212,809
Income tax payable	52,884
Short-term borrowings	4,235,673	10,768,745
Current portion of long-term borrowings	4,161,549	2,850,128
Current portion of operating lease liabilities	195,955	151,983
Total current liabilities	31,455,647	55,080,402
Long-term borrowings	13,540,034	14,146,541
Operating lease liabilities	173,660	53,834
Other non-current liabilities		28,718
TOTAL LIABILITIES	45,169,341	69,309,495
Commitments and contingencies
Shareholders' equity:
Ordinary shares (par value of US$0.0001 per share; 640,000,000 shares authorized, and 54,065,709 shares issued and outstanding as of December 31, 2022; and 640,000,000 shares authorized, and 55,145,839 shares issued and outstanding as of December 31, 2023)	5,547	5,497
Treasury shares, at cost (1 share as of December 31, 2022 and December 31, 2023)	(4)	(4)
Additional paid-in capital	350,105,518	342,739,268
Accumulated other comprehensive loss	(1,800,088)	(849,305)
Accumulated deficit	(277,751,476)	(258,805,106)
Total shareholders' equity	70,559,497	83,090,350
TOTAL LIABILITIES AND SHAREHOLDERS' EQUITY	$ 115,728,838	$ 152,399,845

CONSOLIDATED BALANCE SHEETS (Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares	Dec. 31, 2023	Dec. 31, 2022
CONSOLIDATED BALANCE SHEETS
Ordinary shares, par value	$ 0.0001	$ 0.0001
Ordinary shares, shares authorized	640,000,000	640,000,000
Ordinary shares, shares issued	55,145,839	54,065,709
Ordinary shares, shares outstanding	55,145,839	54,065,709
Treasury shares	1	1

CONSOLIDATED STATEMENTS OF COMP

CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Revenue
Licensing and collaboration revenue	$ 18,111,491	$ 9,292,724	$ 10,175,258
Operating expenses and income
Research and development expenses	(36,639,146)	(81,339,540)	(68,099,385)
Third parties	(33,978,642)	(46,212,077)	(55,020,367)
Related parties	(2,660,504)	(35,127,463)	(13,079,018)
Administrative expenses	(8,672,843)	(11,873,867)	(14,439,962)
Other operating income, net	3,480,632
Loss from operations	(23,719,866)	(83,920,683)	(72,364,089)
Interest income	4,283,085	377,501	76,166
Interest expense	(1,107,820)	(693,323)	(363,762)
Other income, net	1,843,437	2,168,388	1,778,822
Foreign exchange gain (loss), net	1,446,202	2,555,325	(603,459)
Loss before income tax	(17,254,962)	(79,512,792)	(71,476,322)
Income tax expense	(1,691,408)	(459,055)	(1,701,613)
Net loss attributable to Adagene Inc.'s shareholders	(18,946,370)	(79,971,847)	(73,177,935)
Other comprehensive income (loss)
Foreign currency translation adjustments, net of nil tax	(950,783)	(755,324)	257,000
Total comprehensive loss attributable to Adagene Inc.'s shareholders	(19,897,153)	(80,727,171)	(72,920,935)
Net loss attributable to Adagene Inc.'s shareholders	(18,946,370)	(79,971,847)	(73,177,935)
Accretion of convertible redeemable preferred shares to redemption value			(28,553)
Net loss attributable to ordinary shareholders	$ (18,946,370)	$ (79,971,847)	$ (73,206,488)
Weighted average number of ordinary shares used in per share calculation:
-Basic	54,737,530	54,135,084	50,032,009
-Diluted	54,737,530	54,135,084	50,032,009
Net loss per ordinary share
-Basic	$ (0.35)	$ (1.48)	$ (1.46)
-Diluted	$ (0.35)	$ (1.48)	$ (1.46)

CONSOLIDATED STATEMENTS OF CO_2

CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS (Parenthetical) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS
Foreign currency translation adjustments, tax	$ 0	$ 0	$ 0

CONSOLIDATED STATEMENTS OF CHAN

CONSOLIDATED STATEMENTS OF CHANGES IN SHAREHOLDERS' EQUITY (DEFICIT) - USD ($)	Ordinary shares	Treasury shares	Subscriptions receivable from shareholders	Additional paid-in capital	Accumulated other comprehensive loss	Accumulated deficit	Total
Balance at the beginning at Dec. 31, 2020	$ 1,889		$ (7,172,192)	$ 23,786,652	$ (350,981)	$ (105,655,324)	$ (89,389,956)
Balance at the beginning (in shares) at Dec. 31, 2020	18,888,070
CONSOLIDATED STATEMENTS OF CHANGES IN SHAREHOLDERS' EQUITY (DEFICIT)
Net loss						(73,177,935)	(73,177,935)
Other comprehensive income					257,000		257,000
Exercise of share options (Note 8)	$ 23			226,758			$ 226,781
Exercise of share options (Note 8) (in shares)	233,957						233,958
Issuance of ordinary shares under performance incentive plan (Note 8)	$ 2			416,749			$ 416,751
Issuance of ordinary shares under performance incentive plan (Note 8) (in shares)	23,734
Subscription from shareholders			381,282				381,282
Sharebased compensation, adjustments to additional paid-in capital				18,679,658			18,679,658
Accretion of convertible redeemable preferred shares to redemption value				(28,553)			(28,553)
Conversion of convertible redeemable preferred shares to ordinary shares upon the completion of initial public offering ("IPO")	$ 2,725			154,475,235			154,477,960
Conversion of preferred shares to ordinary shares upon the completion of initial public offering ("IPO") (in shares)	27,249,824
Issuance of ordinary shares upon IPO, net of issuance cost	$ 1,057			147,094,280			147,095,337
Issuance of ordinary shares upon IPO, net of issuance cost (in shares)	10,571,375
Purchase of treasury shares under share repurchase program (Note 16)		$ (2,361,576)					(2,361,576)
Purchase of treasury shares under share repurchase program (Note 16) (in shares)		(295,174)
Retirement of treasury shares (Note 16)	$ (20)	$ 1,741,971		(1,750,041)			(8,090)
Retirement of treasury shares (Note 16) (in shares)	(201,100)	201,100
Surrender of ordinary shares for repayment of promissory notes (Note 8)	$ (49)		$ 6,790,910	(6,800,807)			(9,946)
Surrender of ordinary shares for repayment of promissory notes (Note 8) (in shares)	(491,119)
Balance at the end at Dec. 31, 2021	$ 5,627	$ (619,605)		336,099,931	(93,981)	(178,833,259)	156,558,713
Balance at the end (in shares) at Dec. 31, 2021	56,274,741
Balance at the end, Treasury shares (in shares) at Dec. 31, 2021		(94,074)
CONSOLIDATED STATEMENTS OF CHANGES IN SHAREHOLDERS' EQUITY (DEFICIT)
Net loss						(79,971,847)	(79,971,847)
Other comprehensive income					(755,324)		(755,324)
Exercise of share options (Note 8)	$ 20			323,192			$ 323,212
Exercise of share options (Note 8) (in shares)	197,975						197,975
Issuance of ordinary shares under performance incentive plan (Note 8)	$ 10			391,985			$ 391,995
Issuance of ordinary shares under performance incentive plan (Note 8) (in shares)	99,999
Sharebased compensation, adjustments to additional paid-in capital				10,520,282			10,520,282
Purchase of treasury shares under share repurchase program (Note 16)		$ (3,976,681)					(3,976,681)
Purchase of treasury shares under share repurchase program (Note 16) (in shares)		(1,512,932)
Retirement of treasury shares (Note 16)	$ (160)	$ 4,596,282		(4,596,122)
Retirement of treasury shares (Note 16) (in shares)	(1,607,005)	(1,607,005)
Balance at the end at Dec. 31, 2022	$ 5,497	$ (4)		342,739,268	(849,305)	(258,805,106)	$ 83,090,350
Balance at the end (in shares) at Dec. 31, 2022	54,965,710
Balance at the end, Treasury shares (in shares) at Dec. 31, 2022		(1)					(1)
CONSOLIDATED STATEMENTS OF CHANGES IN SHAREHOLDERS' EQUITY (DEFICIT)
Net loss						(18,946,370)	$ (18,946,370)
Other comprehensive income					(950,783)		(950,783)
Exercise of share options (Note 8)	$ 1			5,499			$ 5,500
Exercise of share options (Note 8) (in shares)	10,000						10,000
Issuance of ordinary shares under performance incentive plan (Note 8)	$ 7			89,093			$ 89,100
Issuance of ordinary shares under performance incentive plan (Note 8) (in shares)	69,225
Share-based compensation	$ 42			7,271,658			7,271,700
Share-based compensation (in shares)	425,905
Balance at the end at Dec. 31, 2023	$ 5,547	$ (4)		$ 350,105,518	$ (1,800,088)	$ (277,751,476)	$ 70,559,497
Balance at the end (in shares) at Dec. 31, 2023	55,470,840
Balance at the end, Treasury shares (in shares) at Dec. 31, 2023		(1)					(1)

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Cash flows from operating activities:
Net loss	$ (18,946,370)	$ (79,971,847)	$ (73,177,935)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	980,053	1,145,995	1,125,032
Net loss on disposal of property, equipment, software and operating lease right-of-use asset	9,365	6,811	18,973
Share-based compensation	7,271,700	10,520,282	18,679,658
Interest income on promissory notes			(9,946)
Amortization of right-of use assets and interest of lease liabilities	228,405	303,535
Foreign exchange loss (gain), net	(1,446,202)	(2,555,325)	603,459
Changes in operating assets and liabilities:
Accounts receivable, net		3,000,000	(3,000,000)
Prepayments and other current assets	1,649,878	(881,402)	(231,287)
Amount due from related parties	397,405	3,887,238	(4,374,274)
Other non-current assets	24,687	(40,297)	(24,210)
Accounts payable	(572,372)	344,509	1,511,640
Contract liabilities	(15,107,276)	9,607,276	4,774,464
Amount due to related parties	(2,609,011)	8,857,276	7,930,703
Accruals and other current liabilities	(122,201)	(823,928)	1,057,491
Lease liabilities	(237,401)	(280,465)
Income tax payable	52,884	(1,657,450)	1,657,450
Deferred tax liabilities		(44,163)	44,163
Other non-current liabilities	(28,383)	(29,732)
Net cash used in operating activities	(28,454,839)	(48,611,687)	(43,414,619)
Cash flows from investing activities:
Placement of short-term investments	(47,000,000)
Withdrawal of short-term investments	47,000,000
Proceeds from disposal of property, equipment and software	7,656	4,892
Purchase of property, equipment and software	(85,012)	(690,938)	(2,509,926)
Net cash used in investing activities	(77,356)	(686,046)	(2,509,926)
Cash flows from financing activities:
Proceeds from borrowings	8,133,775	25,830,030	4,386,860
Proceeds from share subscriptions			381,282
Proceeds from exercise of share options	5,500	323,212	231,521
Proceeds from initial public offering, net of underwriting commissions			149,411,950
Repayment of borrowings	(13,506,221)	(4,353,588)	(5,089,717)
Payment of initial public offering costs			(1,595,088)
Purchase of treasury shares under stock repurchase program		(3,976,681)	(2,361,576)
Costs for retirement of treasury shares			(8,090)
Net cash generated from (used in) financing activities	(5,366,946)	17,822,973	145,357,142
Effect of exchange rate on cash and cash equivalents	74,720	842,195	(192,352)
Net increase (decrease) in cash and cash equivalents	(33,824,421)	(30,632,565)	99,240,245
Cash and cash equivalents at the beginning of year	143,758,678	174,391,243	75,150,998
Cash and cash equivalents at the end of year	109,934,257	143,758,678	174,391,243
Supplemental cash flow disclosures:
Interest paid	1,047,717	603,680	359,569
Income tax paid	1,376,856	2,433,241
Cash paid for fixed operating lease costs included in the measurement of lease obligations in operating activities	225,542	313,929
Right-of-use assets obtained in exchange for operating lease obligations	$ 179,919	217,227
Non-cash activities:
Accretion of convertible redeemable preferred shares to redemption value			28,553
Conversion of preferred shares			154,477,960
Retirement of treasury shares		$ 4,596,282	1,741,971
Surrender of ordinary shares for repayment of promissory notes			$ 6,800,856

ORGANIZATION AND BASIS OF PRESE

ORGANIZATION AND BASIS OF PRESENTATION	12 Months Ended
	Dec. 31, 2023
ORGANIZATION AND BASIS OF PRESENTATION
ORGANIZATION AND BASIS OF PRESENTATION	1. ORGANIZATION AND BASIS OF PRESENTATION Adagene Inc. (the “Company”) is a limited liability company incorporated in the Cayman Islands on February 25, 2011. The Company, together with its subsidiaries (collectively, the “Group”), are principally engaged in research, development and production of monoclonal antibody drugs for cancers. On February 8, 2021, the Company’s registration statement relating to its initial public offering (“IPO”) of its American Depositary Shares (“ADSs”) was declared effective by the Securities and Exchange Commission (“SEC”) and the shares of its ADSs began trading on the NASDAQ Global Market on February 9, 2021. The public offering price of the ADSs sold in the IPO was $19.00 per ADS. The IPO closed on February 11, 2021, pursuant to which the Company issued 8,457,100 ADSs, including the exercise in full of the underwriters’ option to purchase 1,103,100 additional ADSs from the Company. The Company received net proceeds of approximately $145.9 million, after underwriting discounts, commissions and estimated offering expenses. Each ADS represents one and one quarter (1.25) ordinary shares of the Company. Upon the completion of the IPO, all outstanding shares of the convertible redeemable preferred shares were converted into ordinary shares. As of December 31, 2023, the Company’s principal subsidiaries are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Percentage of legal ​ ​ ​ ​ Date of ​ Place of ​ ownership ​ ​ Entity incorporation incorporation by the Company Principal activities Adagene (Hong Kong) Limited ​ December 12, 2011 Hong Kong 100 % Investment holding, and research and development of innovative medicines Adagene Incorporated ​ September 20, 2017 The United States of America 100 % Research and development of innovative medicines Adagene (Suzhou) Limited ​ February 28, 2012 The People’s Republic of China (“PRC” or “China”) 100 % Research and development of innovative medicines Adagene Australia PTY Ltd. ​ May 30, 2018 ​ Australia ​ 100 % Research and development of innovative medicines Adagene PTE. Ltd. ​ March 27, 2020 ​ Singapore ​ 100 % Research and development of innovative medicines Adagene AG ​ August 31, 2020 Switzerland 100 % Research and development of innovative medicines Adagene Project C1 PTE. Ltd. ​ March 25, 2022 Singapore 100 % Research and development of innovative medicines ​

SUMMARY OF SIGNIFICANT ACCOUNTI

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	12 Months Ended
	Dec. 31, 2023
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	2. SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Basis of presentation The accompanying consolidated financial statements have been prepared in accordance with U.S. generally accepted accounting principles (“U.S. GAAP”). References to specific GAAP principles throughout these notes to the accompanying financial statements are to the Accounting Standards Codification (“ASC”), as published by the U.S. Financial Accounting Standards Board (“FASB”). Principles of Consolidation The consolidated financial statements of the Group include the financial statements of the Company and its subsidiaries. All significant intercompany balances and transactions have been eliminated upon consolidation. Use of estimates The preparation of consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, disclosures of contingent assets and liabilities at the balance sheet dates and the reported amounts of expenses during the reporting periods. Significant estimates and assumptions reflected in the Group’s consolidated financial statements include, but are not limited to, licensing and collaboration revenue recognition, research and development expense allocation, the useful lives and impairment of long-lived assets, tax valuation allowance, share-based compensation expenses, and measurement of right-of-use assets and lease liabilities. Management bases the estimates on historical experience and various other assumptions that are believed to be reasonable, the results of which form the basis for making judgments about the carrying values of assets and liabilities. Actual results could materially differ from those estimates. Foreign currency translation The functional currency of the Company, Adagene (Hong Kong) Limited, Adagene Incorporated, Adagene PTE. Ltd. and Adagene Project C1 PTE. Ltd. is the United States dollar (“US$”). The functional currency of the Company’s PRC subsidiary is Renminbi (“RMB”). The functional currency of the Company’s Australian subsidiary is Australian dollar (“AU$”). The functional currency of the Company’s Swiss subsidiary is Swiss Franc (“CHF”). The determination of the respective functional currency is based on the criteria stated in ASC 830, Foreign Currency Matters Transactions denominated in foreign currencies are remeasured into the functional currency at the exchange rates quoted by the People’s Bank of China (the “PBOC”) prevailing on the transaction dates. Monetary assets and liabilities denominated in foreign currencies are re-measured at the exchange rates prevailing at the balance sheet date. Non-monetary items that are measured in terms of historical costs in foreign currency are re-measured using the exchange rates at the dates of the initial transactions. Exchange gains and losses are included in the consolidated statements of comprehensive loss. Assets and liabilities are translated at the exchange rates at the balance sheet date, equity accounts are translated at historical exchange rates and revenues, expenses, gains and losses are translated using the average rate for the year. Translation adjustments are reported as accumulated comprehensive loss and are shown as a separate component of other comprehensive loss in the consolidated statements of comprehensive loss. Cash and cash equivalents Cash and cash equivalents primarily consist of cash and demand deposits which are highly liquid. The Group considers highly liquid investments that are readily convertible to known amounts of cash and with original maturities from the date of purchase of three months or less to be cash equivalents. All cash and cash equivalents are unrestricted as to withdrawal and use. Accounts receivable and allowance for doubtful accounts Account receivable is recorded when the Group has an unconditional right to consideration. A right to consideration is unconditional if only the passage of time is required before payment of that consideration is due. Accounts receivable is carried at net realizable value. The allowance for credit losses reflects the best estimate of future losses over the contractual life of outstanding accounts receivable and is determined on the basis of historical experience, specific allowances for known troubled accounts, other currently available information including customer financial condition, and both current and forecasted economic conditions. Fair value measurements The Group applies ASC 820, Fair Value Measurements and Disclosures Level 1—Observable inputs that reflect quoted prices (unadjusted) for identical assets or liabilities in active markets. Level 2—Other inputs that are directly or indirectly observable in the marketplace. Level 3—Unobservable inputs which are supported by little or no market activity. ASC 820 describes three main approaches to measuring the fair value of assets and liabilities: (1) market approach; (2) income approach; and (3) cost approach. The market approach uses prices and other relevant information generated from market transactions involving identical or comparable assets or liabilities. The income approach uses valuation techniques to convert future amounts to a single present value amount. The measurement is based on the value indicated by current market expectations about those future amounts. The cost approach is based on the amount that would currently be required to replace an asset. The carrying amounts of cash and cash equivalent, accounts receivable, amounts due to related parties and other current assets, accounts payable, amounts due to related parties, accrued liabilities and other current liabilities and short-term borrowings approximate their fair values because of their generally short maturities. The carrying amount of long-term borrowings approximate their fair values since they bear interest rates which approximate market interest rates. The Group did not transfer any assets or liabilities in or out of Level 3 during the years ended December 31, 2022 or 2023 The Group had no financial assets and liabilities measured and recorded at fair value on a nonrecurring basis as of December 31, 2022 and 2023. Property, equipment and software Property and equipment and software are stated at cost less accumulated depreciation and amortization. Depreciation and amortization are computed using the straight-line method over the estimated useful lives of the assets as follows: ​ ​ ​ ​ Category Estimated Useful Life Machinery and laboratory equipment ​ 5 years Vehicles ​ 4 years Furniture and tools ​ 3 - 5 years Electronic equipment ​ 3 years Computer software ​ 3 - 5 years Leasehold improvements ​ Lesser of lease terms or estimated useful lives of the assets ​ Repair and maintenance costs are charged to expense as incurred, whereas the cost of renewals and betterments that extend the useful lives of property, equipment and software are capitalized as additions to the related assets. Retirements, sales and disposals of assets are recorded by removing the cost and accumulated depreciation and amortization from the asset and accumulated depreciation and amortization accounts with any resulting gain or loss reflected in the consolidated statements of comprehensive loss. Impairment of long-lived assets The Group evaluates the recoverability of its long-lived assets, including fixed assets and intangible assets with finite lives, for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be fully recoverable. When these events occur, the Group measures impairment by comparing the carrying amount of the assets to the estimated undiscounted future cash flows expected to result from the use of the assets and their eventual disposition. If the sum of the expected undiscounted cash flows is less than the carrying amount of the assets, the Group recognizes an impairment loss based on the excess of the carrying amount of the assets over their fair value. Fair value is generally determined by discounting the cash flows expected to be generated by the assets, when the market prices are not readily available. The adjusted carrying amount of the assets is the new cost basis and is depreciated over the assets’ remaining useful lives. Long-lived assets are grouped with other assets and liabilities at the lowest level for which identifiable cash flows are largely independent of the cash flows of other assets and liabilities. No impairment loss was recorded for the years ended December 31, 2021, 2022 and 2023. Segment reporting In accordance with ASC 280, Segment Reporting , the Group’s chief operating decision maker (“CODM”) has been identified as the Chief Executive Officer. The Group’s CODM reviews the consolidated results of operations when making decisions about allocating resources and assessing performance of the Group. The Group operates and manages it business as a single segment. No geographical segments are presented as a substantial portion of the Group’s long-lived assets are located in the PRC with the exception of certain laboratory and electronic equipment which are located in the U.S. Revenue recognition At contract inception of collaboration and out-licensing arrangements, the Group analyzes its arrangements to assess whether they are within the scope of ASC 808, Collaborative Arrangements Revenue from Contracts with Customers The Group adopted ASC 606 for all periods presented. To determine revenue recognition for arrangements that an entity determines are within the scope of ASC 606, the entity performs the following five steps: (i) identify the contract(s) with a customer; (ii) identify the performance obligations in the contract; (iii) determine the transaction price, including variable consideration, if any; (iv) allocate the transaction price to the performance obligations in the contract; and (v) recognize revenue when (or as) the entity satisfies a performance obligation. The Group only applies the five-step model to contracts when it is probable that the entity will collect substantially all the consideration to which it is entitled in exchange for the goods or services it transfers to the customer. The Group reviews the contract to determine which performance obligations are distinct and represent a promise to provide distinct goods or services or a series of distinct goods or services as defined by the standard. The Group recognizes as revenue the amount of the transaction price that is allocated to each performance obligation as and when that performance obligation is satisfied. Licenses of Intellectual Property: Research and Development Services : The portion of a transaction price allocated to research and development services performance obligations is deferred and recognized as collaboration revenue over time as delivery or performance of such services occurs. Milestone Payments: At the inception of each arrangement that includes development, commercialization, and regulatory milestone payments, the Group evaluates whether the milestones are considered probable of being reached and to the extent that a significant reversal of cumulative revenue would not occur in future periods, estimates the amount to be included in the transaction price using the most likely amount method. The transaction price is then allocated to each performance obligation on a relative stand-alone selling price basis, for which the Group recognizes revenue as or when the performance obligations under the contract are satisfied. At the end of each subsequent reporting period, the Group re-evaluates the probability of achieving such development milestones and any related constraint, and if necessary, adjust the estimate of the overall transaction price. Any such adjustments are recorded on a cumulative catch-up basis, which would affect revenues and earnings in the period of adjustment. Royalties: Contract assets and contract liabilities When a customer pays consideration before the Group transfers products or services, the Group records its obligation as a contract liability; When the Group satisfies its performance obligations by providing products or services to a customer before the customer pays consideration and before payment is due, the Group recognizes its rights to consideration as a contract asset. Other operating income, net Other operating income, net included a one-time compensation payment from a contract manufacturer in relation to company losses for a preclinical-related outsourcing arrangement. Research and development expenses Elements of research and development expenses primarily include (1) payroll and other related costs of personnel engaged in research and development activities, (2) costs related to pre-clinical testing of the Group’s technologies under development and clinical trials such as payments to contract research organizations (“CRO”) and contract manufacturing organizations (“CMO”), investigators and clinical trial sites that conduct the clinical studies; (3) costs to develop the product candidates, including raw materials and supplies, product testing, depreciation and amortization, and facility related expenses, and (4) other research and development expenses. Research and development costs are expensed as incurred when the related research and development services are provided to the Group and the resulting assets, if any, have no alternative future uses. As of December 31, 2022 and 2023, the Group had several ongoing clinical studies in various clinical trial stages. The contracts with CRO and CMO are generally cancellable, with notice, at the Group’s option. The Group did not record any accrued expenses related to cancellation of CRO or CMO contracts as of December 31, 2022 or 2023 as the Group did not have any plan to cancel the existing CRO or CMO contracts. Government subsidies Government subsidies primarily consist of financial subsidies received from provincial and local governments for operating a business in their jurisdictions and compliance with specific policies promoted by the governments. The Group’s PRC based subsidiary received government subsidies from certain local government. The Group’s government subsidies consist of specific subsidies and other subsidies. Specific subsidies are subsidies that the local government has set certain conditions for the subsidies. Other subsidies are the subsidies that the local government has not set any conditions and are not tied to future trends or performance of the Group, receipt of such subsidy income is not contingent upon any further actions or performance of the Group and the amounts do not have to be refunded under any circumstances. These specific subsidies are recorded as other non-current liabilities upon receipt and are recognized as other income when the conditions are met. Other subsidies are recognized as other income upon receipt as further performance by the Group is not required. In addition, the Group’s Australian subsidiary received research and development tax incentive from the Australian Taxation Office in 2021, 2022 and 2023. The tax incentive was recognized as other income upon receipt as the incentive was not dependent upon having a tax liability and further performance by the Group was not required. Government subsidies of US $1.4 million, US $2.1 million and US $1.5 million were received and recognized as other income during the years ended December 31, 2021, 2022 and 2023, respectively. Leases In accordance with ASC 842 adopted on January 1, 2022, the Group determines if an arrangement is or contains a lease at inception. Operating leases are included in operating lease right-of-use (“ROU”) assets and lease liabilities on the consolidated balance sheet. Lease liabilities that become due within one year of the balance sheet date are classified as current liabilities. The Group does not have any finance leases since the adoption date. ROU assets represent the right to use an underlying asset for the lease term and lease liabilities represent the obligation to make lease payments arising from the lease. ROU assets and lease liabilities are calculated as the present value of the lease payments not yet paid. As the rate implicit in the Group’s leases is not typically readily available, the Group uses an incremental borrowing rate based on the information available at the lease commencement date in determining the present value of lease payments. This incremental borrowing rate reflects the fixed rate at which the Group could borrow the amount of the lease payments in the same currency, for a similar term, in a similar economic environment. ROU assets include any lease prepayments and are reduced by lease incentives. Operating lease expense for lease payments is recognized on a straight-line basis over the lease term. Lease terms are based on the non-cancelable term of the lease and may contain options to extend the lease when it is reasonably certain that the Group will exercise that option. The Group has elected to adopt the following lease policies in conjunction with the adoption of ASU 2016-02: (i) elect for each lease not to separate non-lease components from lease components and instead to account for each separate lease component and the non-lease components associated with that lease component as a single lease component; (ii) for leases that have lease terms of 12 months or less and does not include a purchase option that is reasonably certain to exercise, the Group elected not to apply ASC 842 recognition requirements; and (iii) the Group elected to apply the package of practical expedients for existing arrangements entered into prior to January 1, 2022 to not reassess (a) whether an arrangement is or contains a lease, (b) the lease classification. Comprehensive income (loss) Comprehensive income (loss) is defined as the changes in equity of the Group during a period from transactions and other events and circumstances excluding transactions resulting from investments by shareholders and distributions to shareholders. Accumulated other comprehensive income (loss) of the Group includes foreign currency translation adjustments related to the Group and its subsidiaries whose functional currency is not US$. Income taxes The Group follows the liability method of accounting for income taxes in accordance with ASC 740, Income Taxes The Group evaluates its uncertain tax positions using the provisions of ASC 740, which prescribes a recognition threshold that a tax position is required to meet before being recognized in the consolidated financial statements. The Group recognizes in the consolidated financial statements the benefit of a tax position which is “more likely than not” to be sustained under examination based solely on the technical merits of the position assuming a review by tax authorities having all relevant information. Tax positions that meet the recognition threshold are measured using a cumulative probability approach, at the largest amount of tax benefit that has a greater than fifty percent likelihood of being realized upon settlement. It is the Group’s policy to recognize interest and penalties related to unrecognized tax benefits, if any, as a component of income tax expense. Borrowings Borrowings are recognized initially at fair value, net of transaction costs incurred. Borrowings are subsequently stated at amortized cost; any difference between the proceeds (net of transaction costs) and the redemption value is recognized in the consolidated statements of comprehensive loss over the period of the borrowings using the effective interest method. Share-based compensation The Company grants restricted shares and stock options to eligible employees and nonemployees and accounts for share-based compensation in accordance with ASC 718, Compensation—Stock Compensation Share-based compensation awards are measured at the grant date fair value of the awards and recognized as expenses (a) immediately at the grant date if no vesting conditions are required; (b) for share-based awards granted with only service conditions, using the straight-line method over the vesting period; or (c) for share-based awards granted with service conditions and performance conditions, using the graded vesting method over the vesting period if and when the Company concludes that it is probable that the performance conditions will be achieved. A change in any of the terms or conditions of share-based awards is accounted for as a modification of the awards. The Group calculates incremental compensation expense of a modification as the excess of the fair value of the modified awards over the fair value of the original awards immediately before its terms are modified at the modification date. For vested awards, the Group recognizes incremental compensation cost in the period when the modification occurs. For awards not being fully vested, the Group recognizes the sum of the incremental compensation expense and the remaining unrecognized compensation expense for the original awards over the remaining requisite service period after modification. Net loss per share In accordance with ASC 260, Earnings Per Share , basic net loss per share is computed by dividing net loss attributable to ordinary shareholders by the weighted average number of unrestricted ordinary shares outstanding during the year using the two-class method. Under the two-class method, net loss is allocated between ordinary shares and other participating securities based on dividends declared (or accumulated) and participating rights in undistributed earnings as if all the earnings for the reporting period had been distributed. Diluted net loss per share is calculated by dividing net loss attributable to ordinary shareholders, as adjusted for the effect of dilutive ordinary equivalent shares, if any, by the weighted average number of ordinary and dilutive ordinary equivalent shares outstanding during the period. Ordinary equivalent shares include ordinary shares issuable upon the exercise of share options, using the treasury stock method. Ordinary share equivalents are excluded from the computation of diluted earnings per share if their effects are anti-dilutive. For the periods presented herein, the computation of basic net loss per share using the two-class method is not applicable as the Group does not have participating securities that have contractual rights and obligations to share in the losses of the Group. Employee defined contribution plan As stipulated by the regulations of the PRC, full-time employees of the Group are entitled to staff welfare benefits including medical care, welfare subsidies, unemployment insurance and pension benefits through a PRC government-mandated multi-employer defined contribution plan. The Group is required to accrue for these benefits based on certain percentages of the qualified employees’ salaries. The Group is required to make contributions to the plans out of the amounts accrued. The PRC government is responsible for the medical benefits and the pension liability to be paid to these employees and the Group’s obligations are limited to the amounts contributed. The Group has no further payment obligations once the contributions have been paid. The Group recorded employee benefit expenses of US$2,223,493, US$2,984,251 and US$2,584,392 for the years ended December 31, 2021, 2022 and 2023, respectively. Concentration of risks Concentration of credit risk As of December 31, 2022 and 2023, the amount of cash and cash equivalents of US$8,617,157 and US$6,538,253 respectively, were held at major financial institutions located in Mainland China, and US$135,141,521 and US$103,396,004,respectively, were deposited with major financial institutions located outside of Mainland China. Management believes that these financial institutions are of high credit quality and continually monitors the credit worthiness of these financial institutions. Accounts receivable, if any, is typically unsecured and denominated in US$ and/or RMB and is derived from revenues earned from customers. The Group manages credit risk of accounts receivable through ongoing monitoring of the outstanding balances. Concentration of suppliers For the year ended December 31, 2021 and 2022, a significant portion of the Group’s research and development services were purchased from one supplier group, who collectively accounted for 18.5%, and 34.1% of the Group’s total research and development services purchases, respectively. For the year ended December 31, 2023, there were no suppliers who collectively accounted for more than 10% of the Group’s total research and development services. Business and economic risk The Group believes that changes in any of the following areas could have a material adverse effect on the Group’s future consolidated financial position, results of operations or cash flows: changes in the overall demand for services; competitive pressures due to new entrants; advances and new trends in new technologies and industry standards; changes in certain strategic relationships; regulatory considerations and risks associated with the Group’s ability to attract employees necessary to support its growth. The Group’s operations could also be adversely affected by significant political, regulatory, economic and social uncertainties in the PRC. Foreign currency exchange rate risk A significant portion of the Group’s businesses are transacted in RMB, which is not a freely convertible currency. On January 1, 1994, the PRC government abolished the dual rate system and introduced a single rate of exchange as quoted daily by the PBOC. However, the unification of the exchange rates does not imply that the RMB may be readily convertible into US$ or other foreign currencies. All foreign exchange transactions continue to take place either through the PBOC or other banks authorized to buy and sell foreign currencies at the exchange rates quoted by the PBOC. Approval of foreign currency payments by the PBOC or other institutions requires submitting a payment application form together with suppliers’ invoices, shipping documents and signed contracts. From July 21, 2005, the RMB is permitted to fluctuate within a narrow and managed band against a basket of certain foreign currencies. For U.S. dollar against RMB, there was appreciation of approximately 9.24% in the year ended December 31, 2022 and appreciation of approximately 1.70% in the year ended December 31, 2023, respectively. It is difficult to predict how market forces or PRC or U.S. government policy may impact the exchange rate between the RMB and the U.S. dollar in the future. The functional currency and the reporting currency of the Company are the US$. However, the Group incurs portions of our expenses, and derives revenues, in currencies other than US$, in particular, the RMB. Any significant fluctuation of the valuation of RMB may materially affect the Group’s cash flows, expenses, losses and financial position, and the value of any dividends payable on the American Depositary Shares in US$. Recently issued accounting pronouncements The Group is an emerging growth company (“EGC”) as defined by the Jumpstart Our Business Startups Act (“JOBS Act”). The JOBS Act provides that an EGC can take advantage of extended transition periods for complying with new or revised accounting standards. This allows an EGC to delay adoption of certain accounting standards until those standards would otherwise apply to private companies. The Group elected to take advantage of the extended transition periods. However, this election will not apply should the Group cease to be classified as an EGC. New and amended standards adopted by the Group In June 2016, the FASB issued ASU No. 2016-13, Financial Instruments—Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments New and amended standards not yet adopted by the Group In August 2020, FASB issued ASU 2020-06, Debt—Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging—Contracts in Entity’s Own Equity (Subtopic 815-40): Accounting for Convertible Instruments and Contracts in an Entity’s Own Equity Debt—Debt with Conversion and Other Options In November 2023, FASB issued ASU 2023-07, Segment Reporting (Topic 280), Improvements to Reportable Segment Disclosures, which improves the disclosures about a public entity’s reportable segments and address requests from investors for additional, more detailed information about a reportable segment’s expenses. The standard shall be applied retrospectively to all prior periods presented in the financial statements. The standard is effective for fiscal years beginning after December 15, 2023. The Group has evaluated the impact of this accounting standard update on its consolidated financial statements and assessed the impact of the adoption to be immaterial. In December 2023, FASB issued ASU 2023-09, Income Taxes (Topic 740), Improvements to Income Tax Disclosures, which enhances the transparency and decision usefulness of income tax disclosures. The standard is effective for public entities for annual periods beginning after December 15, 2024. For entities other than public business entities, the amendments are effective for annual periods beginning after December 15, 2025. The standard allows the amendments to be applied the standard on a prospective basis or a retrospective basis. The Group has evaluated the impact of this accounting standard update on its consolidated financial statements and assessed the impact of the adoption to be immaterial.

PREPAYMENTS AND OTHER CURRENT A

PREPAYMENTS AND OTHER CURRENT ASSETS	12 Months Ended
	Dec. 31, 2023
PREPAYMENTS AND OTHER CURRENT ASSETS
PREPAYMENTS AND OTHER CURRENT ASSETS	3. PREPAYMENTS AND OTHER CURRENT ASSETS Prepayments and other current assets consisted of the following: ​ ​ ​ ​ ​ ​ ​ ​ As of December 31, ​ 2022 2023 ​ ​ US$ ​ US$ Prepayments 1,161,910 591,383 Deposits (a) 2,970,421 1,790,637 Others 804,992 905,425 ​ 4,937,323 3,287,445 Note (a): The deposits represented the amounts that the Group paid to its CRO vendors for various outsourced research and development programs according to the terms of respective CRO agreements. The Group expects to recover the deposits if the programs fail or the agreements are cancelled.

PROPERTY, EQUIPMENT AND SOFTWAR

PROPERTY, EQUIPMENT AND SOFTWARE, NET	12 Months Ended
	Dec. 31, 2023
PROPERTY, EQUIPMENT AND SOFTWARE, NET
PROPERTY, EQUIPMENT AND SOFTWARE, NET	4. PROPERTY, EQUIPMENT AND SOFTWARE, NET Property, equipment and software consisted of the following: ​ ​ ​ ​ ​ ​ ​ ​ As of December 31, ​ 2022 2023 ​ ​ US$ ​ US$ Machinery and laboratory equipment ​ 5,293,386 5,201,479 Leasehold improvements ​ 1,055,271 1,037,675 Electronic equipment ​ 1,863,963 1,818,352 Furniture and tools ​ 29,684 42,821 Vehicles ​ 80,266 78,928 Software ​ 369,698 363,943 Total property, equipment and software ​ 8,692,268 8,543,198 Less: accumulated depreciation and amortization ​ (5,909,305) (6,708,077) Net book value ​ 2,782,963 1,835,121 ​ Depreciation and amortization expenses recognized for the years ended December 31, 2021, 2022 and 2023

ACCRUALS AND OTHER CURRENT LIAB

ACCRUALS AND OTHER CURRENT LIABILITIES	12 Months Ended
	Dec. 31, 2023
ACCRUALS AND OTHER CURRENT LIABILITIES
ACCRUALS AND OTHER CURRENT LIABILITIES	5. ACCRUALS AND OTHER CURRENT LIABILITIES Accrued liabilities and other current liabilities consisted of the following: ​ ​ ​ ​ ​ ​ ​ ​ As of December 31, ​ 2022 2023 ​ ​ US$ ​ US$ Professional service fees ​ 1,647,490 1,194,199 Payroll and related liabilities ​ 1,104,365 ​ 1,177,301 Other taxes and surcharge ​ 349,039 510,259 Others ​ 111,915 119,749 ​ 3,212,809 3,001,508 ​

BORROWINGS

BORROWINGS	12 Months Ended
	Dec. 31, 2023
BORROWINGS
BORROWINGS	6. BORROWINGS ​ ​ ​ ​ ​ ​ ​ ​ As of December 31, ​ 2022 2023 ​ ​ US$ ​ US$ Current ​ ​ ​ Short-term borrowings: ​ ​ ​ Bank loans ​ 10,768,745 4,235,673 Current portion of long-term borrowings ​ 2,850,128 4,161,549 Total current borrowings ​ 13,618,873 8,397,222 Non-Current ​ ​ ​ Long-term borrowings: ​ ​ ​ Bank loans ​ 14,146,541 13,540,034 Total non-current borrowings ​ 14,146,541 13,540,034 Total borrowings ​ 27,765,414 21,937,256 ​ Short-term borrowings In June 2020, the Group borrowed a loan with the amount of RMB10,000,000 (equivalent to approximately US$1,532,591) from Agricultural Bank of China Limited for a term of one year at the interest rate of 4.2% per annum. The borrowing was repaid in June 2021. In September 2020, the Group borrowed a loan with the amount of RMB5,000,000 (equivalent to approximately US$766,295) from Bank of Ningbo Co., Ltd. for a term of one year at the interest rate of 4.2% per annum. The borrowing was repaid in September 2021. In November 2020, the Group borrowed a loan with the amount of RMB5,000,000 (equivalent to approximately US$770,962) from China Merchants Bank Co., Ltd. for a term of one year at the interest rate of 4.1% per annum. The borrowing was repaid in November 2021. In November 2020, the Group borrowed another loan with the amount of RMB5,000,000 (equivalent to approximately US$770,962) from China Merchants Bank Co., Ltd. for a term of one year at the interest rate of 4.1% per annum. The borrowing was also repaid in November 2021. In June 2021, the Group borrowed a loan with the amount of RMB9,900,000 (equivalent to approximately US$1,552,771) from Agricultural Bank of China Limited for a term of one year at the interest rate of 4.05% per annum. The borrowing was repaid in May 2022. In August 2021, the Group borrowed another loan with the amount of RMB10,000,000 (equivalent to approximately US$1,568,455) from Agricultural Bank of China Limited for a term of one year at the interest rate of 4.05% per annum. The borrowing was repaid in August 2022. In March 2022, the Group borrowed a loan with the amount of RMB9,900,000 (equivalent to approximately US$1,421,474) from China Merchants Bank Co., Ltd. for a term of one year at the interest rate of 3.90% per annum. The borrowing was repaid in March 2023. In April 2022, the Group borrowed another loan with the amount of RMB20,100,000 (equivalent to approximately US$2,886,024) from China Merchants Bank Co., Ltd. for a term of one year at the interest rate of 3.70% per annum. The borrowing was repaid in April 2023. In July 2022, the Group borrowed a loan with the amount of RMB20,000,000 (equivalent to approximately US$2,871,665) from Bank of Jiangsu Co., Ltd. for a term of one year at the interest rate of 3.70% per annum. The borrowing was repaid in July 2023. In December 2022, the Group borrowed a loan with the amount of RMB25,000,000 (equivalent to approximately US$3,589,582) from China Construction Bank Corporation for a term of one year at the interest rate of 3.65% per annum. The borrowing was repaid in December 2023. In January 2023, the Group borrowed a loan with the amount of RMB10,000,000 (equivalent to approximately US$1,411,891) from Bank of Ningbo Co., Ltd for a term of one year at the interest rate of 3.9% per annum. The borrowing was repaid in January 2024. In March 2023, the Group borrowed another loan with the amount of RMB10,000,000 (equivalent to approximately US$1,411,891) from China Everbright Bank Co., Ltd for a term of one year at the interest rate of 3.8% per annum. In July 2023, the Group borrowed a loan with the amount of RMB10,000,000 (equivalent to approximately US$1,411,891) from Bank of Ningbo Co., Ltd for a term of one year at the interest rate of 3.85% per annum. Long-term borrowings In February 2019, the Group borrowed a loan with the amount of RMB7,500,000 (equivalent to approximately US$1,076,874) from Shanghai Pudong Development Bank Co., Ltd. for a term of three years at the interest rate of 5.46% per annum. The Group repaid RMB375,000 (equivalent to approximately US$53,844) in 2019, RMB1,250,000 (equivalent to approximately US$179,479) in 2020, RMB3,375,000 (equivalent to approximately US$484,594) in 2021 and RMB2,500,000 (equivalent to approximately US$358,958) in 2022. As of December 31, 2021, RMB2,500,000 (equivalent to approximately US$358,958) repayable within twelve months for this agreement was classified as “Current portion of long-term borrowing” on the consolidated balance sheets. The loan was fully repaid in February 2022. In June 2019, the Group borrowed a loan with the amount of RMB6,000,000 (equivalent to approximately US$861,500) from Shanghai Pudong Development Bank Co., Ltd. for a term of three years at the interest rate of 5.23% per annum. The Group repaid RMB300,000 (equivalent to approximately US$43,075) in 2019, RMB1,000,000 (equivalent to approximately US$143,583) in 2020, RMB2,700,000 (equivalent to approximately US$387,675) in 2021, and RMB2,000,000 (equivalent to approximately US$287,167) in 2022. As of December 31, 2021, RMB2,000,000 (equivalent to approximately US$287,167) repayable within twelve months for this agreement was classified as “Current portion of long-term borrowing” on the consolidated balance sheets. The loan was fully repaid in June 2022. In September 2020, the Group borrowed a loan with the amount of RMB16,500,000 (equivalent to approximately US$2,329,620) from Shanghai Pudong Development Bank Co., Ltd. for a term of three years at the interest rate of 4.27% per annum. The Group repaid RMB1,650,000 (equivalent to approximately US$232,962) in 2021,RMB3,850,000 (equivalent to approximately US$543,578) in 2022 and RMB11,000,000 (equivalent to approximately US$1,553,080) in 2023. As of December 31, 2022, RMB11,000,000 (equivalent to approximately US$1,553,080) repayable within twelve months for this agreement was classified as “Current portion of long-term borrowing” on the consolidated balance sheets. The loan was fully repaid in September 2023. In September 2021, the Group borrowed a loan with the amount of RMB8,500,000 (equivalent to approximately US$1,200,107) from Shanghai Pudong Development Bank Co., Ltd. for a term of three years at the interest rate of 4.05% per annum. The Group repaid RMB425,000 (equivalent to approximately US$60,005) in 2022 and RMB850,000 (equivalent to approximately US$120,011) in 2023. As of December 31, 2022 and 2023, RMB850,000 (equivalent to approximately US$120,011) and RMB7,225,000 (equivalent to approximately US$1,020,092) repayable within twelve months for this agreement were classified as “Current portion of long-term borrowing” on the consolidated balance sheets, respectively. In May 2022, the Group borrowed a loan with the amount of RMB30,000,000 (equivalent to approximately US$4,235,673) from Agricultural Bank of China Limited for a term of three years at the interest rate of 4.00% per annum. The Group repaid RMB3,000,000 (equivalent to approximately US$423,567) in 2023. As of December 31, 2022 and 2023, RMB3,000,000 (equivalent to approximately US$423,567) and RMB5,000,000 (equivalent to approximately US$705,945) repayable within twelve months for this agreement was classified as “Current portion of long-term borrowing” on the consolidated balance sheets, respectively. Also in May 2022, the Group borrowed a loan with the amount of RMB20,000,000 (equivalent to approximately US$2,823,782) from Shanghai Pudong Development Bank Co., Ltd. for a term of three years at the interest rate of 4.00% per annum. The Group repaid RMB500,000 (equivalent to approximately US$70,595) in 2022 and RMB1,500,000 (equivalent to approximately US$211,784) in 2023. As of December 31, 2022 and 2023, RMB1,500,000 (equivalent to approximately US$211,784) and RMB9,500,000 (equivalent to approximately US$1,341,297) repayable within twelve months for this agreement was classified as “Current portion of long-term borrowing” on the consolidated balance sheets, respectively. In August 2022, the Group borrowed a loan with the amount of RMB9,900,000 (equivalent to approximately US$1,397,772) from Agricultural Bank of China Limited for a term of three years at the interest rate of 4.00% per annum. The Group repaid RMB1,000,000 (equivalent to approximately US$141,189) in 2023. As of December 31, 2022 and 2023, RMB1,000,000 (equivalent to approximately US$141,189) and RMB2,000,000 (equivalent to approximately US$282,378) repayable within twelve months for this agreement was classified as “Current portion of long-term borrowing” on the consolidated balance sheets, respectively. Also in August 2022, the Group borrowed a loan with the amount of RMB20,000,000 (equivalent to approximately US$2,823,782) from Shanghai Pudong Development Bank Co., Ltd. for a term of three years at the interest rate of 4.00% per annum. The Group repaid RMB1,000,000 (equivalent to approximately US$141,189) in 2023. As of December 31, 2022 and 2023, RMB1,000,000 (equivalent to approximately US$141,189) and RMB2,000,000 (equivalent to approximately US$282,378) repayable within twelve months for this agreement was classified as “Current portion of long-term borrowing” on the consolidated balance sheets, respectively. In November 2022, the Group borrowed a loan with the amount of RMB9,900,000 (equivalent to approximately US$1,397,772) from Agricultural Bank of China Limited for a term of three years at the interest rate of 4.00% per annum. The Group repaid RMB1,000,000 (equivalent to approximately US$141,189) in 2023. As of December 31, 2022 and 2023, RMB1,000,000 (equivalent to approximately US$141,189) and RMB2,000,000 (equivalent to approximately US$282,378) repayable within twelve months for this agreement was classified as “Current portion of long-term borrowing” on the consolidated balance sheets, respectively. Also in November 2022, the Group borrowed a loan with the amount of RMB10,000,000 (equivalent to approximately US$1,411,891) from Shanghai Pudong Development Bank Co., Ltd. for a term of three years at the interest rate of 4.00% per annum. The Group repaid RMB500,000 (equivalent to approximately US$70,595) during in 2023. As of December 31, 2022 and 2023, RMB500,000 (equivalent to approximately US$70,595) and RMB1,000,000 (equivalent to approximately US$141,189) repayable within twelve months for this agreement was classified as “Current portion of long-term borrowing” on the consolidated balance sheets. In April 2023, the Group borrowed a loan with the amount of RMB7,000,000 (equivalent to approximately US$988,324) from Shanghai Pudong Development Bank Co., Ltd. for a term of three years at the interest rate of 3.90% per annum. The Group repaid RMB150,000 (equivalent to approximately US$21,178) in 2023. As of December 31, 2023, RMB550,000 (equivalent to approximately US$77,654) repayable within twelve months for this agreement was classified as “Current portion of long-term borrowing” on the consolidated balance sheets. In August 2023, the Group borrowed a loan with the amount of RMB10,000,000 (equivalent to approximately US$1,411,891) from Bank of Jiangsu Co., Ltd. for a term of eighteen months at the interest rate of 3.80% per annum. As of December 31, 2023, RMB100,000 (equivalent to approximately US$14,119) repayable within twelve months for this agreement was classified as “Current portion of long-term borrowing” on the consolidated balance sheets. In September 2023, the Group borrowed another loan with the amount of RMB10,000,000 (equivalent to approximately US$1,411,891) from Bank of Jiangsu Co., Ltd. for a term of eighteen months at the interest rate of 3.80% per annum. As of December 31, 2023, RMB100,000 (equivalent to approximately US$14,119) repayable within twelve months for this agreement was classified as “Current portion of long-term borrowing” on the consolidated balance sheets. The proceeds from the loans were primarily used to pay for the Group’s research and development activities in China, including CMC costs of clinical and preclinical programs. As of December 31, 2022 and 2023, none of the Group’s borrowings were collateralized in the respective loan agreements. Future maturities of short-term borrowings and long-term borrowings Future principal maturities of short-term borrowings and long-term borrowings as of December 31, 2023 were as follows: ​ ​ ​ ​ ​ ​ As of December 31, ​ ​ 2023 ​ US$ 2024 ​ 8,397,222 2025 ​ 13,116,467 2026 ​ 423,567 ​ ​ 21,937,256 ​

CONVERTIBLE REDEEMABLE PREFERRE

CONVERTIBLE REDEEMABLE PREFERRED SHARES	12 Months Ended
	Dec. 31, 2023
CONVERTIBLE REDEEMABLE PREFERRED SHARES
CONVERTIBLE REDEEMABLE PREFERRED SHARES	7. CONVERTIBLE REDEEMABLE PREFERRED SHARES From November 2011 to December 2019, the Company issued various series of convertible redeemable preferred shares (collectively the “Preferred Shares”) to certain investors. Upon completion of the IPO on February 11, 2021, each of the then outstanding Preferred Shares was automatically converted into one ordinary share. As of December 31, 2022 and 2023, there were no Preferred Shares issued or outstanding. Prior to the IPO, the Company concluded that the Preferred Shares were not redeemable, but were probable to become redeemable. The Company accreted changes in the redemption value over the period from the date of issuance to the IPO date for the year ended December 31, 2021, using the interest method. The Company had no Preferred Share activities for the years ended December 31, 2022 and 2023. The Company’s Preferred Share activities for the year ended December 31, 2021 were summarized below: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Preferred Shares Series A-1 Series A-2 Series B Series C-1 Series C-2 Series C-3 Total ​ ​ US$ ​ US$ ​ US$ ​ US$ ​ US$ ​ US$ ​ US$ Balance as of December 31, 2020 ​ 5,473,957 3,000,000 27,999,995 48,975,456 18,999,999 50,000,000 154,449,407 Accretion of Series C-1 Preferred Shares to redemption value ​ — ​ — ​ — ​ 28,553 ​ — ​ — ​ 28,553 Conversion of Preferred Shares to Ordinary Shares ​ (5,473,957) (3,000,000) (27,999,995) (49,004,009) (18,999,999) (50,000,000) (154,477,960) Balance as of December 31, 2021 ​ — — — — — — — ​

SHARE-BASED COMPENSATION

SHARE-BASED COMPENSATION	12 Months Ended
	Dec. 31, 2023
SHARE-BASED COMPENSATION
SHARE-BASED COMPENSATION	8. SHARE-BASED COMPENSATION On November 7, 2015, the Company adopted a share incentive plan (the “2015 Plan”). Under the 2015 Plan, the Company’s Board of Directors has approved that a maximum aggregate number of shares that may be issued pursuant to all awards granted shall be 4,336,126. In September 2017, the Company replaced the 2015 Plan with the amended and restated share incentive plan (the “2017 Plan”) and increased the maximum number of shares issuable to 6,336,126. In December 2019, the Company replaced the 2017 Plan with the second amended and restated share incentive plan (the “2019 Plan”) and further increased the maximum number of shares issuable to 11,391,131. The terms of the 2015 Plan, 2017 Plan and 2019 Plan are substantially the same other than the maximum aggregate number of shares the Company may issue under the respective plan. Share options containing only service conditions granted to each grantee under the share incentive plan will generally be exercisable upon the grantee renders service to the Company in accordance with a stipulated vesting schedule. Grantees are generally subject to a vesting schedule of no longer than five years Share options containing both service conditions and performance conditions granted to each grantee under the share incentive plan shall become eligible for vesting upon the occurrence of their applicable performance conditions (including but not limited to the occurrence of an IPO, the completion of business and operational goals, etc.). On November 9, 2020, the Company passed a board resolution to waive the vesting schedules and conditions of 2,375,000 share options granted to certain management members. Pursuant to this board resolution, these management members exercised all related share options at the original exercise price per share ranging from US$1.83 to US$2.26. As a result, 2,375,000 ordinary shares were issued to these management members. These management members paid the exercise price by issuing recourse promissory notes in the total amount of US$5,197,650. The Company had the repurchase right to buy back such shares at the original exercise price if the grantees did not meet the original vesting conditions. The Company assessed and considered that given such arrangement allows the shares received on exercise be returned to the Company if the original vesting conditions are not satisfied, there has been no substantial change to the vesting conditions and the Company shall continue to account for the share awards in accordance with their original terms. As of December 31, 2023, there were 325,000 shares unvested according to the original vesting conditions. On January 16, 2021, the Company passed a board resolution whereby certain management members surrendered a total of 491,119 ordinary shares as repayment for their respective promissory notes issued in connection with the exercising of options granted to them. In the meantime, the Company further granted these management members the right to repurchase the surrendered shares by way of new option grants with an exercise price of US$13.85 per share. The fair values of these share options were US$7.85 per option, determined by using the binomial option valuation model. The share-based compensation expense related to these share options were recognized immediately upon grants. Pursuant to the same board resolution, the 2021 Performance Incentive Plan (the “2021 Plan”) was also adopted, under which an aggregate of 2,994,000 ordinary shares shall be reserved for issuance, and the share limit will automatically increase on the first trading day in January of each year (commencing with 2022) by an amount equal to (1) 5% of the total number of the Company’s outstanding ordinary shares on December 31 of the prior year, or (2) such lesser number as determined by the board of directors. From March 12, 2021 to December 22, 2021, pursuant to the 2021 Plan, a total of 1,303,000 share options were granted to certain employees by 15 batches, with exercise price ranging from US$5.92 to US$17.56, respectively. In addition, 23,734 ordinary shares were issued to certain management personnel on March 16, 2021 pursuant to the 2021 Plan. On January 7, 2022, the Company passed a board resolution, pursuant to which the vesting schedules and conditions of 2,060,308 share options granted to certain employees were modified. Share options as to which the applicable performance milestones have been met are no longer subject to the time-based vesting requirement. The share options vested (or to be vested) for each year (commencing from 2021) shall be equal to the lesser of (i) 25% of the total number of share options of each grantee (“Annual Cap”) and (ii) the number of shares as determined by the Compensation Committee based on the extent to which any performance milestones were achieved during that year (“Credited Shares”), plus any Credited Share of earlier years that have not previously vested due to the Annual Cap. In addition, the performance milestones applicable to the share options that remain outstanding were also modified. As a result of the modification, the Company recognized an incremental fair value of US$2,337,697. From February 7, 2022 to December 27, 2022, pursuant to the 2021 Plan, a total of 2,640,598 share options were granted to certain employees, with exercise price ranging from US$0.80 to US$5.60, respectively. In addition, 99,999 ordinary shares were issued to certain management personnel on March 8, 2022 pursuant to the 2021 Plan. From April 12, 2023 to December 27, 2023, pursuant to the 2021 Plan, a total of 3,442,500 share options were granted to certain employees, with exercise price ranging from US$0.94 to US$1.33, respectively. In addition, 425,905 ordinary shares were issued to certain management personnel in January 2023 pursuant to the 2021 Plan. 69,225 ordinary shares were issued to certain employees as stock bonus in April 2023. As of December 31, 2022 and 2023, among all the share options granted to date, 4,776,906 and 4,826,906 share options contained both service conditions and performance conditions, respectively. All other share options granted contain only service conditions. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted ‑ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Average ​ Weighted ​ ​ ​ ​ ​ ​ Weighted ‑ ​ Grant ​ Average ​ ​ ​ ​ ​ ​ Average ​ Date ​ Remaining ​ Aggregate ​ ​ Number of ​ Exercise ​ Fair ​ Contractual ​ Intrinsic ​ Options Price Value Term Value ​ ​ ​ ​ US$ per ​ US$ per ​ ​ ​ ​ ​ ​ ​ ​ option ​ option ​ Years ​ US$ Outstanding at December 31, 2020 ​ 3,294,467 1.75 6.65 8.78 33,410,968 Granted ​ 1,894,119 12.31 8.39 — — Exercised ​ (233,958) 0.99 5.13 — — Forfeited ​ (145,550) ​ 3.02 ​ 7.71 ​ — ​ — Outstanding at December 31, 2021 ​ 4,809,078 ​ 5.91 ​ 7.38 ​ 8.68 ​ 2,619,574 Granted ​ 2,640,598 ​ 3.28 ​ 2.13 ​ — ​ — Exercised ​ (197,975) ​ 2.08 ​ 6.95 ​ — ​ — Forfeited ​ (964,789) 6.75 7.57 — — Outstanding at December 31, 2022 ​ 6,286,912 4.80 5.16 8.44 94,990 Granted ​ 3,442,500 ​ 1.14 ​ 0.72 ​ — ​ — Exercised ​ (10,000) ​ 0.55 ​ 5.72 ​ — ​ — Forfeited ​ (952,530) ​ 4.59 ​ 3.45 ​ — ​ — Outstanding at December 31, 2023 ​ 8,766,882 ​ 3.39 ​ 3.60 ​ 8.24 ​ 2,011,843 Vested and expected to vest at December 31, 2023 ​ 8,766,882 ​ 3.39 ​ 3.60 ​ 8.24 ​ 2,011,843 Exercisable at December 31, 2022 ​ 2,070,533 ​ 6.35 ​ 6.87 ​ 7.62 ​ 55,880 Exercisable at December 31, 2023 ​ 2,448,076 ​ 5.79 ​ 6.64 ​ 6.75 ​ 207,499 ​ The aggregate intrinsic value in the table above represents the difference between the exercise price of the awards and the fair value of the underlying ordinary shares at each reporting date, for those awards that had exercise price below the estimated fair value of the relevant ordinary shares. The aggregate fair value of the equity awards vested during the years ended December 31, 2021, 2022, and 2023 was US$13,833,856, US$11,929,903 and US$6,742,535, respectively. As of December 31, 2023, the total unrecognized employee share based compensation expense was US$16,658,848, all of which may be adjusted for actual forfeitures occurring in the future. Total unrecognized compensation cost will be recognized over a weighted average period of 1.64 years as of December 31, 2023. Fair value of share options The fair value of share options was determined using the binomial option valuation model, with the assistance from an independent third-party appraiser. The binomial model requires the input of highly subjective assumptions, including the expected volatility, the exercise multiple, the risk-free rate and the dividend yield. For expected volatility, the Group has made reference to historical volatility of several comparable companies in the same industry. The exercise multiple was estimated as the average ratio of the stock price to the exercise price of when employees would decide to voluntarily exercise their vested share options. The risk-free rate for periods within the contractual life of the share options is based on the market yield of U.S. Treasury Bonds in effect at the time of grant. The dividend yield is based on the expected dividend policy over the contractual life of the share options. The assumptions used to estimate the fair value of the share options granted were as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ For the years ended ​ ​ December 31, ​ 2021 2022 2023 Risk‑free interest rate 1.11% - 1.67% ​ 1.92% - 4.25% ​ 3.38% - 4.86% Dividend yield 0% ​ 0% ​ 0% Expected volatility range 73.1% - 75.5% ​ 74.2% - 74.9% ​ 72.6% - 73.1% Exercise multiple 2.2 - 2.8 ​ 2.2 - 2.8 ​ 2.2 - 2.8 Contractual life 10 years ​ 10 years ​ 10 years ​ Total share-based compensation expenses recognized for the years ended December 31, 2021, 2022 and 2023 were as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ For the years ended December 31, ​ 2021 2022 2023 ​ ​ US$ ​ US$ ​ US$ Research and development expenses 13,582,746 7,227,298 4,860,548 Administrative expenses 5,096,912 3,292,984 2,411,152 Total share‑based compensation expenses 18,679,658 10,520,282 7,271,700 ​

COLLABORATION ARRANGEMENTS

COLLABORATION ARRANGEMENTS	12 Months Ended
	Dec. 31, 2023
COLLABORATION ARRANGEMENTS
COLLABORATION ARRANGEMENTS	9. COLLABORATION ARRANGEMENTS Guilin Sanjin Pharmaceutical Co., Ltd. License Agreement In December 2018, the Group entered into (i) a collaboration agreement (the “Sanjin Greater China Agreement”) that covers Greater China with Guilin Sanjin Pharmaceutical Co., Ltd. (“Sanjin”) and certain of its subsidiaries (collectively, “Sanjin Parties”) and (ii) a collaboration agreement (the “Sanjin ROW Agreement”, together with the Sanjin Greater China Agreement, the “2018 Sanjin Agreements”) that covers the regions other than Greater China with Sanjin. Pursuant to the Sanjin Greater China Agreement, the Group licensed the Chinese intellectual property directly related to a monospecific antibody molecule that binds to the PD-L1 target (the “PD-L1 Project”), including patent rights, patent application rights and technologies based on the core sequence of the molecule, to Sanjin Parties. Sanjin Parties will own all the Chinese intellectual property developed in the exercise of Sanjin Parties’ rights under the agreement, including but not limited to improvements (including combination products), clinical trials, regulatory filings, and commercialization rights relating thereto. The Group also granted Sanjin Parties a royalty-free license to use our other existing intellectual property and improvements thereto which are related to the PD-L1 Project for the purposes of exploiting its rights and performing its obligations under the agreement. Sanjin Parties will enjoy all the economic benefits deriving from the PD-L1 Project in Greater China, including but not limited to patent transfer fee, licensing fee, sales revenue and sales commission, etc. Sanjin Parties will pay the Group (i) single-digit percentage of net sales of the products that use the licensed antibody after such products enter the market and (ii) a low to mid-low double-digit percentage of the profits resulting from any transfer of the license to any third parties depending on the timing of the transfer relative to the development stage of the product. The Group also received RMB10,000,000 (equivalent to approximately US$1,511,168) upfront fee upon the effectiveness of the agreement from Sanjin Parties, which was recognized as revenue in 2018. No revenues related to this agreement has been recognized in any of the years presented in the accompanying financial statements. Pursuant to the Sanjin ROW Agreement, the Group granted Sanjin a royalty-free license to use all intellectual property relating to (i) the collaboration under the agreement that the Group controlled before the Group entered into the agreement or acquired independently of the agreement and (ii) improvements thereto for the purposes of exploiting its rights and performing its obligations under the agreement. Any intellectual property generated independently by a party under the agreement will be solely owned by that party who generated such intellectual property, and any intellectual property generated from cooperation between the Group and Sanjin’s affiliates in connection with the collaboration will be jointly owned. The Group retain the ownership of patent rights of key intellectual property pertaining to PD-L1 outside of the Greater China. In addition, all the results obtained by Sanjin relating to the research and development of any new antibody developed under the agreement will be owned by Sanjin. The Group retain a majority of the economic benefits derived from the Sanjin ROW Agreement, including but not limited to any patent transfer fee, licensing fee and gains realized under such transfer. In case the Group intend to transfer to a third party our share of economic interests in any country outside of Greater China, the Group must notify Sanjin and Sanjin will receive a right of first refusal if it pays the Group a deposit equal to a low double-digit percentage of the consideration that the Group expect to receive from such third party. If Sanjin waives the right of first refusal, the Group can proceed with the transfer, provided that the final transaction price with the third party is not lower than the amount of the offering price that was included in the Group’s notice to Sanjin. The Group agreed not to (i) independently develop any monospecific antibodies that bind to the PD-L1 target or (ii) grant any rights associated with such antibodies to any third parties during the three-year In the event that the failure of the development of the product candidate solely arises from the Group’s research and development basis specified under this agreement, Sanjin has the right to claim back all the payment made to the Group. The Group considers the possibility of occurrence of such event is remote. Dragon Boat Biopharmaceutical (Shanghai) Limited License Agreement In May 2019, the Group entered into (i) a collaboration agreement that covers Greater China (the “Dragon Boat Greater China Agreement”) and (ii) a collaboration agreement that covers the regions other than Greater China (the “Dragon Boat ROW Agreement,” together with the Dragon Boat Greater China Agreement, the “2019 Dragon Boat Agreements”), with Dragon Boat Biopharmaceutical (Shanghai) Limited (“Dragon Boat”), a subsidiary of Sanjin. Pursuant to the Dragon Boat Greater China Agreement, the Group will license the Chinese intellectual property directly related to a certain monospecific antibody molecule that binds to a specified target (the “Specified Project”), including the patent rights, patent application rights and technologies based on the core sequence of the molecule, to Dragon Boat. Dragon Boat will own all the Chinese intellectual property developed in the exercise of Dragon Boat’s rights under the agreement, including but not limited to improvements (including combination products), clinical trials, regulatory filings, and commercialization rights relating thereto. The Group also granted Dragon Boat a royalty-free license to use our other existing intellectual property and improvements thereto which are related to the Specified Project for the purposes of exploiting its rights and performing its obligations under the agreement. Dragon Boat will enjoy all the economic benefits deriving from the Specified Project in Greater China, including but not limited to patent transfer fee, licensing fee, sales revenue and sales commission, etc. and will pay the Group (i) certain high-six figure dollar milestone payments upon the achievement of certain milestones (including milestones of launch of pre-clinical safety evaluation animal test, obtaining Investigational New Drug (“IND”) approval in PRC and completion of clinical phase I test in PRC) and (ii) a single-digit percentage of net sales of the products that use the licensed antibody after such products enter the market. Pursuant to the Dragon Boat ROW Agreement, the Group granted Dragon Boat a royalty-free license to use all intellectual property relating to (i) the collaboration under the agreement that the Group controlled before the Group entered into the agreement or acquired independently of the agreement and (ii) improvements thereto for the purposes of exploiting its rights and performing its obligations under the agreement. Any intellectual property generated independently by a party under the agreement will be solely owned by that party who generated such intellectual property, and any intellectual property generated from cooperation between the Group and Dragon Boat in connection with the collaboration will be jointly owned. The Group retain the ownership of patent rights of key intellectual property pertaining to the specified target outside of the Greater China. In addition, all the results obtained by Dragon Boat relating to the research and development of any new antibody developed under the agreement will be owned by Dragon Boat. The Group retains a majority of the economic benefits derived from the Dragon Boat ROW Agreement, including but not limited to any patent transfer fee, licensing fee and gains realized under such transfer. In case the Group intend to transfer to a third party our share of economic interests in any country outside of Greater China, the Group must notify Dragon Boat and Dragon Boat will receive a right of first refusal if it pays the Group a deposit equal to a low double-digit percentage of the consideration that the Group expects to receive from such third party. If Dragon Boat waives the right of first refusal, the Group can proceed with the transfer, provided that the final transaction price with the third party is not lower than the amount of the offering price that was included in our notice to Dragon Boat. Under the 2019 Dragon Boat Agreements, the Group agreed not to (i) independently develop any monospecific antibodies that bind to the specified target or (ii) grant any rights associated with such antibodies to any third parties during the three-year period from the effective date of the agreements. The exclusivity obligation does not prevent the Group from (i) developing or granting any licenses to third parties for intellectual property that covers bispecific antibodies, ADCs, diagnostic antibodies, nano-particles and masked antibody against the specific target and (ii) continuing to provide antibody screening service that were commenced before the execution of the Dragon Boat Greater China Agreement and either party has the independent right to conduct combination therapy studies outside of the Greater China. Either nonbreaching party may terminate the 2019 Dragon Boat Agreements if the other party’s ability to comply with its obligations under the agreements is negatively affected by contingencies such as failure to maintain operation or changes in core project management and the other party fails to take effective remedial measures. Each agreement automatically terminates upon the termination of the other agreement. Upon the rescission or termination, Dragon Boat will return to the Group all the intellectual property, documents and data provided by the Group under the 2019 Dragon Boat Agreements. In the event that the failure of the development of the product candidate solely arises from the Group’s research and development basis specified under this agreement, Dragon Boat has the right to claim back all the payment made to the Group. The risk of failure is considered remote upon recognition of revenue. Upfront fee of RMB4,000,000 (equivalent to approximately US$620,011) received in 2019, and milestone fee of RMB4,000,000 (equivalent to approximately US$620,011) received in 2021 were recognized as licensing revenue in 2021 as the performance obligation was satisfied by the Group and certain milestone events were achieved. No additional revenue was recognized for the years ended December 31, 2022 and 2023. ADC Therapeutics SA License and Collaboration Agreements In April 2019, the Group entered into a material transfer and collaboration agreement (the “ADCT Collaboration Agreement”) and a license agreement (the “ADCT License Agreement”) with ADC Therapeutics SA (“ADC Therapeutics”). These two agreements are combined as a single contract as the agreements were negotiated as a package with a single commercial objective. Under the ADCT Collaboration Agreement, the Group is eligible to receive up to a low-seven-figure dollar amount in consideration for the Group’s exclusivity obligations, upon achievement of certain development milestones (including milestones of delivery of certain amino acid sequences and successful outcome of the first in-vivo study) and upon ADC Therapeutics’ election to proceed with development for the two elected targets. Apart from performance obligation to deliver the amino acid sequences of the corresponding masking peptides, the Group is not required to perform any additional research and development services. The Group also granted ADC Therapeutics an exclusive target reservation right for one year Subject to the exercise of the options contained in the ADCT Collaboration Agreement, the Group has granted ADC Therapeutics, with respect to each elected target, an exclusive, worldwide, perpetual and irrevocable (subject only to the termination provisions) license (with the right to grant sublicenses) to develop, make, use, commercialize and import the antibody drug conjugates that comprise masked antibodies generated by the Group under these programs. The ADCT Collaboration Agreement has expired in 2023, and ADC Therapeutics elected not to exercise its options for the ADCT License Agreement. Prior to December 31, 2021, the Group recognized US$225,000 of licensing revenue upon delivery of the research results, and US$100,000 as other income due to the expiration of exclusive target reservation right, which is not related to the Group’s major operation activity. For the year ended December 31, 2021, the Group recognized US$225,000 of licensing revenue upon delivery of additional research results. For the years ended December 31, 2022 and 2023, the Group did not recognize additional revenue associated with the agreements. ADCT Material Transfer and Option Agreement In August 2022, the Group entered into a material transfer and option agreement (the “ADCT Material Transfer and Option Agreement”) with ADCT. Under the agreement, Adagene agreed to provide antibodies or antibody sequences to ADCT to conduct further development for a non-refundable fee of US$300,000. ADCT has an exclusive option to negotiate a separate license agreement with the Group, however, there is no requirement for either party to enter into such a license agreement. For the year ended December 31, 2022, the Group recognized revenue of US$300,000 upon delivery of the sequences. ADCT has not exercised the option to negotiate a separate license agreement. No additional revenue was recognized for the year ended December 31, 2023. Exelixis, Inc. Agreements In February 2021, the Group entered into a collaboration and license agreement (the “Exelixis Agreement”) with Exelixis, Inc. (“Exelixis”), pursuant to which the Group agreed to generate masked antibodies with its SAFEbody technology against an initial target selected and a second target to be selected by Exelixis. The Group will generate masked antibodies in the form of alternative compounds in accordance with the program plan for each target at its own cost and deliver the related data packages to Exelixis. Exelixis will select lead compounds (the “Lead Compounds”) to further develop, obtain regulatory approval and commercialize product(s) for each target (the “Products under the Exelixis Agreement”). Under the Exelixis Agreement, the Group will also grant Exelixis an exclusive, worldwide, sublicensable license (the “Adagene License”) upon delivery of the data package to research, develop, make, have made, sell, offer for sale, import and commercialize products containing the masked antibodies to be generated by the Group with respect to both targets. Exelixis will own the inventions relating to the Lead Compounds arising in connection with the Exelixis Agreement. The Exelixis Agreement will remain effective until the expiration of the defined royalty terms of the Products under the Exelixis Agreement, unless terminated by either party. Exelixis may terminate the Exelixis Agreement for any or no reason, in its entirety or on a target-by-target basis. Any payment received by the Group before the termination shall be non-refundable. Under the Exelixis Agreement, Exelixis agreed to pay the Group an upfront non-refundable fee of US$11,000,000. For each target, the Group will be eligible to receive up to US$127,500,000 of milestone payments conditioned upon achieving certain development and regulatory approval milestones, and up to $262,500,000 of sales-based milestone payments. In addition, the Group is also entitled to royalties of mid-single-digit percentage in respect of the aggregate annual net sales of the products developed under the Exelixis Agreement worldwide, subject to certain reductions. In April 2022, the Group entered in a letter agreement (the “Exelixis Letter Agreement”) in reference to the Exelixis Agreement with Exelixis for expanded collaboration in SAFEbody discovery. Under the Exelixis Letter Agreement, the Group will generate additional masked antibodies against the target selected by Exelixis per the Exelixis Agreement. Exelixis agreed to pay the Group an additional upfront non-refundable fee of US$1,100,000. The Group determined that generating masked antibodies with its SAFEbody technology is reflective of a vendor-customer relationship and therefore within the scope of ASC 606. Under the Exelixis Agreement, the delivery of data packages for each target, along with the Adagene License used to develop the related compounds, represents one performance obligation, as they are not distinct from each other. Transaction price is allocated to each one of the two performance obligations using the relative standalone selling price method. The Group records revenue at a point in time, when the data packages for each target were delivered to Exelixis. Considering that the development, regulatory and sales-based milestone payments and the royalties are constrained, the transaction price shall initially only include upfront payment and the milestone payments that are considered probable. Subsequently, once the uncertainty associated with the milestone payments is resolved, the milestone payments shall be included in the total transaction price when it is no longer probable that a significant reversal of cumulative revenue would occur in future periods. The sales-based royalty and sales-based milestones promised in exchange for the Adagene License granted are recognized when (or as) the later of (1) the subsequent sale or usage occurs, or (2) the performance obligation to which some or all of the sales-based royalty or sales-based milestones being allocated has been satisfied (or partially satisfied). For the year ended December 31, 2021, the Group received US$11,000,000 upfront payment and recorded accounts receivable of US$3,000,000 milestone payment, which corresponds to the successful nomination of lead SAFEbody candidates for the initial target under the Exelixis Agreement. The milestone payment was subsequently received in January 2022. For the year ended December 31, 2021, US$8,500,000 was recognized as revenue upon delivery of data packages for the initial target and achievement of the milestone event. For the year ended December 31, 2022, the Group received US$1,100,000 upfront payment under the Exelixis Letter Agreement. No additional revenue was recognized as no relevant performance obligation had been satisfied under either the Exelixis Agreement or the Exelixis Letter Agreement as of December 31, 2022. For the year ended December 31, 2023, the Group received US$3,000,000 milestone payment, which corresponds to the successful nomination of lead SAFEbody candidates for the second target under the Exelixis Agreement. A total of US$9,600,000 was recognized as revenue in 2023, which includes a) US$8,500,000 upon delivery of data packages for the second target and achievement of the milestone event for the second target under the Exelixis Agreement including the US$5,500,000 upfront fee and the aforementioned milestone fee of US$3,000,000, and b) US$1,100,000 upon delivery of additional masked antibodies under the Exelixis Letter Agreement. Sanofi Agreement In March 2022, the Group entered into a collaboration and license agreement (the “Sanofi Agreement”) with Genzyme Corporation, a wholly-owned subsidiary of Sanofi (“Sanofi”), pursuant to which the Group agreed to perform early-stage research activities to develop masked versions of Sanofi candidate antibodies (each a “Target”, and together, “Targets”), using Adagene’s SAFEbody technology for development and commercialization by Sanofi. Sanofi has the ability to advance two initial Targets in the collaboration, followed by an option for two additional Targets. The Group will generate masked antibodies in the form of customized compounds and complete the compound research activities in accordance with the program plan for each Target at its own cost and deliver the compounds and related data packages to Sanofi. Sanofi is solely responsible for later stage research and all clinical, product development and commercialization activities. Under the Sanofi Agreement, the Group granted Sanofi an exclusive, worldwide, sublicensable license to research, develop, use, make, have made, sell, offer for sale, import and commercialize products containing the masked antibodies to be generated by the Group. The Sanofi Agreement will remain effective until the expiration of the defined royalty on a product-by-product and country-by-country basis, unless terminated earlier with cause or by mutual agreements of both parties. Sanofi may terminate the Sanofi Agreement without cause, in its entirety, or on a Target-by-Target or country-by-country basis. Under the Sanofi Agreement, Sanofi agreed to pay the Group an upfront non-refundable fee of US$17,500,000 in consideration of the license granted and the early-stage research activities to generate the compounds. Sanofi is obligated to pay an additional fee if Sanofi exercises the option for additional Targets. For each Target, the Group will be eligible to receive up to US$173,500,000 of milestone payments conditioned upon achieving certain development and regulatory approval milestones, and up to $450,000,000 of sales-based milestone payments. In addition, the Group is also entitled to royalties of mid-single-digit percentage in respect of the aggregate annual net sales of the products developed under the Sanofi Agreement worldwide, subject to certain reductions. The Group then determined that this collaboration is more reflective of a vendor-customer relationship and therefore within the scope of ASC 606. Under the Sanofi Agreement, the performance of early-stage research activities to develop compounds for each Target, along with the grant of the license, represents one performance obligation, as they are not distinct from each other. Transaction price is allocated to each one of the two performance obligations based on the relative standalone selling price. Since the early-stage research activities does not generate an asset for alternative use and the Group has an enforceable right to the upfront payment, the Group records revenue over time using labor hour as the input to assess the satisfaction of the performance obligations. Considering that the development, regulatory and sales-based milestone payments and the royalties are constrained, the transaction price shall initially only include upfront payment and the milestone payments that are considered probable. Subsequently, once the uncertainty associated with the milestone payments is resolved, the milestone payments shall be included in the total transaction price when it is no longer probable that a significant reversal of cumulative revenue would occur in future periods. The sales-based royalty and sales-based milestones promised in exchange for the license granted are recognized when (or as) the later of (1) the subsequent sale or usage occurs, or (2) the performance obligation to which some or all of the sales-based royalty or sales-based milestones being allocated has been satisfied (or partially satisfied). For the year ended December 31, 2022, the Group received US$17,500,000 upfront payment under the Sanofi Agreement. For the years ended December 31, 2022 and 2023, US$8,992,724 and US$8,507,276 were recognized as revenue over time using the input method, respectively.

INCOME TAX EXPENSE

INCOME TAX EXPENSE	12 Months Ended
	Dec. 31, 2023
INCOME TAX EXPENSE
INCOME TAX EXPENSE	10. INCOME TAX EXPENSE PRC Effective from January 1, 2008, the PRC’s statutory, Enterprise Income Tax (“EIT”) rate is 25%. In accordance with the implementation rules of EIT Law, a qualified “Technology Advanced Service Enterprises” (“TASE”) is eligible for a preferential tax rate of 15%. The TASE certificate is effective for three years Adagene (Suzhou) Limited was first recognized as a qualified TASE in March 2015 and renewed in December 2018 and November 2021. Adagene (Suzhou) Limited was authorized to enjoy the preferential tax rate of 15% from 2015 to at least November 2024. Cayman Islands Adagene Inc. is incorporated in the Cayman Islands. Under the current laws of the Cayman Islands Adagene Inc. is not subject to tax on income or capital gain. Additionally, the Cayman Islands does not impose a withholding tax on payments of dividends to shareholders. Hong Kong Adagene (Hong Kong) Limited is incorporated in Hong Kong. Companies registered in Hong Kong are subject to Hong Kong profits tax on the taxable income as reported in their respective statutory financial statements adjusted in accordance with the relevant Hong Kong tax laws. The applicable tax rate in Hong Kong is 16.5%. For the years ended December 31, 2021, 2022 and 2023, Adagene (Hong Kong) Limited did not make any provisions for Hong Kong profit tax as there were no assessable profits derived from or earnings in Hong Kong for any of the periods presented. Under the Hong Kong tax law, Adagene (Hong Kong) Limited is exempted from income tax on its foreign-derived income and there are no withholding taxes in Hong Kong on remittance of dividends. Australia Adagene Australia Pty Ltd. is incorporated in Australia. Companies registered in Australia are subject to Australia profits tax on the taxable income as reported in their respective statutory financial statements adjusted in accordance with the relevant Australia tax laws. The applicable tax rate in Australia is 30%. Adagene Australia Pty Ltd. has no taxable income for all periods presented, therefore, no provision for income taxes is required. Dividends payable by an Australian entity, to non-Australian resident enterprises shall be subject to 30% withholding tax, unless the respective non-Australian resident enterprise’s jurisdiction of incorporation has a tax treaty or arrangements with Australia that provides for a reduced withholding tax rate or an exemption from withholding tax. United States Adagene Incorporated is incorporated in U.S. and is subject to U.S. federal corporate income tax at a rate of 21%. Adagene Incorporated is also subject to state income tax in California of 8.84%. Dividends payable by an U.S. entity, to non-U.S. resident enterprises shall be subject to 30% withholding tax, unless the respective non-U.S. resident enterprise’s jurisdiction of incorporation has a tax treaty or arrangements with U.S. that provides for a reduced withholding tax rate or an exemption from withholding tax. PRC has the tax treaty with U.S. Switzerland Adagene AG is incorporated in Switzerland and is subject to federal corporate income tax at a rate of 8.5%. Adagene AG is also subject to cantonal income tax of 6.5% as well as capital tax of 0.1% in the Canton of Basel subject to certain tax benefits and relief. Dividends payable by a Swiss entity, to non-Swiss resident enterprises shall be subject to 35% withholding tax, unless the respective non-Swiss resident enterprise’s jurisdiction of incorporation has a tax treaty or arrangements with Switzerland that provides for a reduced withholding tax rate or an exemption from withholding tax. Income tax expense (benefit) of the Group for the years ended December 31, 2021, 2022 and 2023 were composed of the following current and deferred amounts: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ For the years ended December 31, ​ 2021 2022 2023 ​ ​ US$ ​ US$ ​ US$ Current: ​ ​ ​ ​ ​ ​ U.S. ​ ​ ​ ​ ​ ​ Federal 1,290,009 672,064 1,502,796 State and local 367,441 (168,846) 188,612 Total current 1,657,450 503,218 1,691,408 Deferred: ​ U.S. ​ ​ ​ ​ ​ ​ Federal 96,804 (96,804) — State and local (52,641) 52,641 — Total deferred 44,163 (44,163) — Income tax expense 1,701,613 459,055 1,691,408 ​ Reconciliation between the income tax expense computed by applying the statutory tax rate to loss before income tax and the actual provision for income tax was as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ For the years ended December 31, ​ 2021 2022 2023 ​ ​ US$ ​ US$ ​ US$ Loss before income tax (71,476,322) (79,512,792) (17,254,962) ​ PRC statutory income tax rate ​ 25 % 25 % 25 % Income tax credit computed at PRC statutory income tax rate ​ (17,869,081) (19,878,198) (4,313,740) ​ Impact of PRC preferential income tax rate as qualified TASE ​ 7,147,633 ​ 7,951,279 ​ 1,725,496 ​ Difference in income tax rates of overseas entities ​ 10,549,985 ​ 10,560,029 ​ (1,012,031) ​ Research and development super-deduction (a) ​ (569,016) (1,724,740) (693,340) ​ Research and development tax credits ​ — ​ (569,575) ​ (668,854) ​ Non-deductible expenses ​ 1,054 3,695 7,241 ​ Foreign derived intangible income deduction ​ — ​ (487,183) ​ (394,979) ​ Changes in valuation allowance ​ 2,277,418 4,517,358 7,064,573 ​ State tax ​ 291,500 ​ 76,127 ​ (22,363) ​ Others ​ (127,880) ​ 10,263 ​ (595) ​ Income tax expense ​ 1,701,613 ​ 459,055 ​ 1,691,408 ​ Note (a): Due to the impacts of research and development super-deduction, the Group’s subsidiary, Adagene (Suzhou) Limited, did not have any income taxes for the years ended December 31, 2021, and 2022. Deferred tax assets and liabilities Deferred taxes were measured using the enacted tax rates for the periods in which the temporary differences are expected to be reversed. The tax effects of temporary differences that give rise to the deferred tax balances as of December 31, 2022 and 2023 were as follows: ​ ​ ​ ​ ​ ​ ​ ​ As of December 31, ​ 2022 2023 ​ ​ US$ ​ US$ Deferred tax assets: ​ ​ ​ Net operating loss carry forward ​ 8,217,976 15,413,070 Tax credit carry forward ​ 391,843 ​ 1,077,073 Capitalized research and development expenses ​ 756,197 ​ — Capitalized inventory ​ 94,954 ​ 72,402 Unrealized foreign exchange gain/losses ​ 116,238 ​ 67,453 Accrued expenses ​ 29,702 ​ — Amortization of right-of-use assets and interest of lease liabilities ​ 546 ​ 676 Gross deferred tax assets ​ 9,607,456 16,630,674 Less: valuation allowance ​ (9,524,497) (16,589,070) Deferred tax assets ​ 82,959 41,604 ​ ​ ​ ​ ​ Deferred tax liabilities: ​ ​ ​ ​ Depreciation and amortization of property, equipment and software ​ (82,959) ​ (41,604) Deferred tax liabilities ​ (82,959) (41,604) Total deferred tax liabilities, net ​ — — ​ Movement of the valuation allowance was as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ 2021 2022 2023 ​ ​ US$ ​ US$ ​ US$ Balance as of January 1 2,729,721 5,007,139 9,524,497 Addition 2,277,418 4,517,358 7,064,573 Balance as of December 31 5,007,139 9,524,497 16,589,070 ​ A valuation allowance is provided to reduce the amount of deferred tax assets if it is considered more likely than not that some portion or all of the deferred tax assets will not be realized in the foreseeable future. In making such determination, the Group evaluates a variety of positive and negative factors including the Group’s operating history, accumulated deficit, the existence of taxable temporary differences and reversal periods. The Group has incurred net accumulated operating losses for income tax purposes since its inception. As of December 31, 2023, the Group had net operating losses for income tax purpose of approximately US$136,672,221. The net operating losses were primarily comprised of: US$25,271,118 from an entity in PRC which expires in years 2029 through 2033; US$4,635,670 derived from an entity Switzerland which expires in years 2028 through 2029; US$5,744,965 derived from an entity in Hong Kong that have an indefinite carryforward; US$11,094,390 derived from an entity in Australia that have an indefinite carryforward subject to meeting certain criteria; US$88,416,478 derived from an entity in the United States which expires beginning year 2038; and, US$1,509,600 derived from entities in Singapore. The Group believes that it is more likely than not that these net accumulated operating losses will not be utilized in the near future. Therefore, the Group has provided full valuation allowances for the deferred tax assets for all subsidiaries as of December 31, 2023. The Group evaluates each uncertain tax position (including the potential application of interest and penalties) based on the technical merits, and measure the unrecognized benefits associated with the tax positions. As of December 31, 2022 and 2023, the Group did not have any unrecognized uncertain tax positions. The Group does not anticipate that the amount of unrecognized tax benefits will significantly change within the next 12 months. The Group conducts business in a number of tax jurisdictions and, as such, is required to file income tax returns in multiple jurisdictions globally. As of December 31, 2023, PRC tax matters are open to examination for the years 2021 through 2023, U.S. federal and state tax matters are open to examination for the years 2020 through 2023, and Australia tax matters are open to examination for the years 2020 through 2023.

NET LOSS PER SHARE

NET LOSS PER SHARE	12 Months Ended
	Dec. 31, 2023
NET LOSS PER SHARE
NET LOSS PER SHARE	11. NET LOSS PER SHARE Basic and diluted net loss per share for the years ended December 31, 2021, 2022 and 2023 were calculated as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ For the Year Ended December 31, ​ ​ 2021 ​ 2022 ​ 2023 ​ US$ US$ US$ Numerator: Net loss attributable to Adagene Inc.’s shareholders (73,177,935) (79,971,847) (18,946,370) Accretion of convertible redeemable preferred shares to redemption value (28,553) — — Net loss attributable to ordinary shareholders (73,206,488) (79,971,847) (18,946,370) Denominator: Weighted‑average number of ordinary shares outstanding—basic and diluted 50,032,009 54,135,084 54,737,530 Net Loss per share—basic and diluted (1.46) (1.48) (0.35) ​ The effects of all outstanding share options and share grant have been excluded from the computation of diluted loss per share for the years ended December 31, 2021, 2022 and 2023 as their effects would be anti-dilutive. The potentially dilutive securities that have not been included in the calculation of diluted net loss per share as their inclusion would be anti-dilutive are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ For the Year Ended December 31, ​ 2021 2022 2023 Incremental shares on share options and share grant 1,739,882 530,298 52,942 ​

RELATED PARTY TRANSACTIONS

RELATED PARTY TRANSACTIONS	12 Months Ended
	Dec. 31, 2023
RELATED PARTY TRANSACTIONS
RELATED PARTY TRANSACTIONS	12. RELATED PARTY TRANSACTIONS a) Related Parties ​ ​ ​ ​ Name of related parties Relationship Peter Luo Chairman, Chief Executive Officer and a principal shareholder of the Company Certain senior management personnel Management and ordinary shareholders of the Company WuXi AppTec Co., Ltd. (“WuXi AppTec Group”) A principal shareholder of the Company WuXi Biologics (Cayman) Inc. Controlled by the ultimate controlling party of a principal shareholder of the Company ​ b) The Group had the following related party balances as of December 31, 2022 and 2023: ​ ​ ​ ​ ​ ​ ​ ​ As of December 31, ​ ​ 2022 ​ 2023 ​ US$ US$ WuXi AppTec Group 503,941 118,594 WuXi Biologics (Cayman) Inc. 115,491 102,416 Certain senior management personnel. ​ — ​ 1,017 Total amounts due from related parties 619,432 222,027 ​ As of December 31, 2022 and 2023, the amounts due from related parties mainly represented prepayments made for the CRO and CMO services. ​ ​ ​ ​ ​ ​ ​ ​ As of December 31, ​ ​ 2022 ​ 2023 ​ US$ US$ WuXi Biologics (Cayman) Inc. 17,840,876 16,371,593 WuXi AppTec Group 1,482,461 341,716 Certain senior management personnel. ​ — ​ 1,017 Total amounts due to related parties 19,323,337 16,714,326 ​ As of December 31, 2022 and 2023, the amounts due to related parties mainly represented payables for the CRO and CMO services. ​ c) The Group had the following related party transactions during the years ended December 31, 2021, 2022 and 2023: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ For the years ended ​ ​ December 31, ​ ​ 2021 ​ 2022 ​ 2023 ​ US$ US$ US$ Receipt of CRO and CMO services: ​ ​ ​ WuXi Biologics (Cayman) Inc. 12,561,276 27,764,750 1,868,815 WuXi AppTec Group 517,742 7,362,713 787,602 Certain senior management personnel. ​ — ​ — ​ 4,087 ​ 13,079,018 35,127,463 2,660,504 ​

LEASES

LEASES	12 Months Ended
	Dec. 31, 2023
LEASES
LEASES	13. LEASES As of December 31, 2022 and 2023, the Group has operating leases recorded on its consolidated balance sheet for certain office spaces that expire on various dates through 2026. The Group does not plan to cancel the existing lease agreements for its existing office spaces prior to their respective expiration dates. The Group’s lease arrangements have no renewal options, rent escalation clauses, restrictions or contingent rents and are all executed with third parties. All of the Group’s leases qualify as operating leases. Information related to operating leases as of December 31, 2022 and 2023 is as follows: ​ ​ ​ ​ ​ ​ ​ ​ As of December 31, ​ ​ 2022 2023 ​ ​ US$ ​ US$ ​ Assets ​ ​ Operating lease right-of-use assets 191,877 ​ 365,103 ​ Liabilities ​ ​ ​ Current portion of operating lease liabilities 151,983 ​ 195,955 ​ Operating lease liabilities 53,834 ​ 173,660 ​ Weighted average remaining lease term (years) 1.3 ​ 2.1 ​ Weighted average discount rate ​ 4.6 % 4.4 % ​ Information related to operating lease activity during the years ended December 31, 2022 and 2023 is as follows: ​ ​ ​ ​ ​ ​ ​ For the Year Ended December 31, ​ ​ 2022 2023 ​ ​ US$ US$ Operating lease rental expense ​ Amortization of right-of-use assets 283,276 ​ 216,305 Expense for short-term leases within 12 months 34,729 ​ 13,514 Interest of lease liabilities 20,259 ​ 12,100 ​ 338,264 ​ 241,919 ​ Maturities of lease liabilities were as follows: ​ ​ ​ ​ ​ ​ ​ As of December 31, ​ ​ 2022 2023 ​ ​ US$ ​ ​ 2023 157,603 ​ — 2024 54,823 ​ 207,155 2025 ​ — ​ 123,546 2026 ​ — ​ 55,499 Total undiscounted lease payments 212,426 ​ 386,200 Less: imputed interest (6,609) ​ (16,585) Total lease liabilities 205,817 ​ 369,615 ​

COMMITMENTS AND CONTINGENCIES

COMMITMENTS AND CONTINGENCIES	12 Months Ended
	Dec. 31, 2023
COMMITMENTS AND CONTINGENCIES
COMMITMENTS AND CONTINGENCIES	14. COMMITMENTS AND CONTINGENCIES Contingencies The Group is currently not involved in any legal or administrative proceedings that may have a material adverse impact on the Group’s business, financial position, cash flows or results of operations.

RESTRICTED NET ASSETS

RESTRICTED NET ASSETS	12 Months Ended
	Dec. 31, 2023
RESTRICTED NET ASSETS
RESTRICTED NET ASSETS	15. RESTRICTED NET ASSETS The Group’s ability to pay dividends may depend on the Group receiving distributions of funds from its PRC subsidiary. Relevant PRC statutory laws and regulations permit payments of dividends by the Group’s PRC subsidiary only out of its retained earnings, if any, as determined in accordance with PRC accounting standards and regulations. The results of operations reflected in the consolidated financial statements prepared in accordance with U.S. GAAP differ from those reflected in the statutory financial statements of the Group’s PRC subsidiary. In accordance with the company law of the PRC, a domestic enterprise is required to provide statutory reserves of at least 10% of its annual after-tax profit until such reserve has reached 50% of its respective registered capital based on the enterprise’s PRC statutory accounts. A domestic enterprise is also required to provide discretionary surplus reserve, at the discretion of the Board of Directors, from the profits determined in accordance with the enterprise’s PRC statutory accounts. The aforementioned reserves can only be used for specific purposes and are not distributable as cash dividends. The Group’s PRC subsidiary was established as domestic invested enterprise and therefore is subject to the abovementioned restrictions on distributable profits. As of December 31, 2022 and 2023, the total restricted net assets of the Company’s subsidiary incorporated in PRC and subjected to restriction amounted to approximately US$1,860,667 for both years. Other subsidiaries are not subjected to such restriction. As a result of these PRC laws and regulations subject to the limit discussed above that require annual appropriations of 10% of after-tax income to be set aside, prior to payment of dividends, as general reserve fund, the Group’s PRC subsidiary is restricted in their ability to transfer a portion of their net assets to the Group. Foreign exchange and other regulations in the PRC further restrict the Group’s PRC subsidiaries from transferring funds to the Company in the form of dividends, loans and advances. As of December 31, 2023, the net asset base for purposes of calculating the proportionate share of restricted net assets of consolidated subsidiaries was US$1,860,667 from the PRC subsidiary. As the restricted net assets of consolidated subsidiaries did not exceed 25% of consolidated net assets as of the most recent fiscal year end, the Group was not required to provide parent company financial information.

Treasury Shares

Treasury Shares	12 Months Ended
	Dec. 31, 2023
Treasury Shares
Treasury Shares	16. Treasury Shares The Group accounts for treasury shares using the cost method. Under this method, the cost incurred to purchase the shares is recorded in the treasury shares account in the consolidated balance sheets. At retirement, the ordinary shares account is charged only for the aggregate par value of the shares. The excess of the acquisition cost of treasury shares over the aggregate par value is recorded entirely in additional paid-in capital (up to the amount credited to the additional paid-in capital upon original issuance of the shares). In the event that treasury share is reissued at an amount different from the cost the Group paid to repurchase the treasury share, the Group will recognize the difference in additional paid-in capital by using the specified identification method. On July 7, 2021, the Board of Directors approved a share repurchase program to repurchase up to US $20 million of outstanding ADSs of the Company, from time to time over a 12 -month period from the date on which a formal stock repurchase plan engagement agreement was signed with a qualified broker-dealer (the “2021 Share Repurchase Program”). The 2021 Share Repurchase Program commenced on July 20, 2021. During the year ended December 31, 2021 and 2022, 236,139 and 1,170,446 outstanding ADSs ( 295,174 and 1,463,057 ordinary shares) were repurchased with a total consideration of US $2,361,576 and US $3,904,399 respectively, under the 2021 Share Repurchase Program. On June 29, 2022, the Board of Directors authorized a share repurchase program to repurchase up to US $10 million of outstanding ADSs of the Company during a period of up to 12 months commencing on July 20, 2022 (the “2022 Share Repurchase Program”). The 2022 Share Repurchase Program was subsequently terminated in July 2022. During the year ended December 31, 2022, 39,900 outstanding ADSs ( 49,875 ordinary shares) was repurchased with a total consideration of US $72,282 under the 2022 Share Repurchase Program . During the year ended December 31, 2023, no shares were repurchased. During the years ended December 31, 2021 and 2022, 160,880 and 1,285,604 ADSs (201,100 and 1,607,005 ordinary shares) repurchased have been retired, respectively. During the year ended December 31, 2023, no shares were retired. As of December 31, 2022 and 2023, there was 1 ADS (approximately 1 ordinary share) held as treasury share, respectively.

SUMMARY OF SIGNIFICANT ACCOUN_2

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Policies)	12 Months Ended
	Dec. 31, 2023
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Basis of presentation	Basis of presentation The accompanying consolidated financial statements have been prepared in accordance with U.S. generally accepted accounting principles (“U.S. GAAP”). References to specific GAAP principles throughout these notes to the accompanying financial statements are to the Accounting Standards Codification (“ASC”), as published by the U.S. Financial Accounting Standards Board (“FASB”).
Principles of Consolidation	Principles of Consolidation The consolidated financial statements of the Group include the financial statements of the Company and its subsidiaries. All significant intercompany balances and transactions have been eliminated upon consolidation.
Use of estimates	Use of estimates The preparation of consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, disclosures of contingent assets and liabilities at the balance sheet dates and the reported amounts of expenses during the reporting periods. Significant estimates and assumptions reflected in the Group’s consolidated financial statements include, but are not limited to, licensing and collaboration revenue recognition, research and development expense allocation, the useful lives and impairment of long-lived assets, tax valuation allowance, share-based compensation expenses, and measurement of right-of-use assets and lease liabilities. Management bases the estimates on historical experience and various other assumptions that are believed to be reasonable, the results of which form the basis for making judgments about the carrying values of assets and liabilities. Actual results could materially differ from those estimates.
Foreign currency translation	Foreign currency translation The functional currency of the Company, Adagene (Hong Kong) Limited, Adagene Incorporated, Adagene PTE. Ltd. and Adagene Project C1 PTE. Ltd. is the United States dollar (“US$”). The functional currency of the Company’s PRC subsidiary is Renminbi (“RMB”). The functional currency of the Company’s Australian subsidiary is Australian dollar (“AU$”). The functional currency of the Company’s Swiss subsidiary is Swiss Franc (“CHF”). The determination of the respective functional currency is based on the criteria stated in ASC 830, Foreign Currency Matters Transactions denominated in foreign currencies are remeasured into the functional currency at the exchange rates quoted by the People’s Bank of China (the “PBOC”) prevailing on the transaction dates. Monetary assets and liabilities denominated in foreign currencies are re-measured at the exchange rates prevailing at the balance sheet date. Non-monetary items that are measured in terms of historical costs in foreign currency are re-measured using the exchange rates at the dates of the initial transactions. Exchange gains and losses are included in the consolidated statements of comprehensive loss. Assets and liabilities are translated at the exchange rates at the balance sheet date, equity accounts are translated at historical exchange rates and revenues, expenses, gains and losses are translated using the average rate for the year. Translation adjustments are reported as accumulated comprehensive loss and are shown as a separate component of other comprehensive loss in the consolidated statements of comprehensive loss.
Cash and cash equivalents	Cash and cash equivalents Cash and cash equivalents primarily consist of cash and demand deposits which are highly liquid. The Group considers highly liquid investments that are readily convertible to known amounts of cash and with original maturities from the date of purchase of three months or less to be cash equivalents. All cash and cash equivalents are unrestricted as to withdrawal and use.
Accounts receivable and allowance for doubtful accounts	Accounts receivable and allowance for doubtful accounts Account receivable is recorded when the Group has an unconditional right to consideration. A right to consideration is unconditional if only the passage of time is required before payment of that consideration is due. Accounts receivable is carried at net realizable value. The allowance for credit losses reflects the best estimate of future losses over the contractual life of outstanding accounts receivable and is determined on the basis of historical experience, specific allowances for known troubled accounts, other currently available information including customer financial condition, and both current and forecasted economic conditions.
Fair value measurements	Fair value measurements The Group applies ASC 820, Fair Value Measurements and Disclosures Level 1—Observable inputs that reflect quoted prices (unadjusted) for identical assets or liabilities in active markets. Level 2—Other inputs that are directly or indirectly observable in the marketplace. Level 3—Unobservable inputs which are supported by little or no market activity. ASC 820 describes three main approaches to measuring the fair value of assets and liabilities: (1) market approach; (2) income approach; and (3) cost approach. The market approach uses prices and other relevant information generated from market transactions involving identical or comparable assets or liabilities. The income approach uses valuation techniques to convert future amounts to a single present value amount. The measurement is based on the value indicated by current market expectations about those future amounts. The cost approach is based on the amount that would currently be required to replace an asset. The carrying amounts of cash and cash equivalent, accounts receivable, amounts due to related parties and other current assets, accounts payable, amounts due to related parties, accrued liabilities and other current liabilities and short-term borrowings approximate their fair values because of their generally short maturities. The carrying amount of long-term borrowings approximate their fair values since they bear interest rates which approximate market interest rates. The Group did not transfer any assets or liabilities in or out of Level 3 during the years ended December 31, 2022 or 2023 The Group had no financial assets and liabilities measured and recorded at fair value on a nonrecurring basis as of December 31, 2022 and 2023.
Property, equipment and software	Property, equipment and software Property and equipment and software are stated at cost less accumulated depreciation and amortization. Depreciation and amortization are computed using the straight-line method over the estimated useful lives of the assets as follows: ​ ​ ​ ​ Category Estimated Useful Life Machinery and laboratory equipment ​ 5 years Vehicles ​ 4 years Furniture and tools ​ 3 - 5 years Electronic equipment ​ 3 years Computer software ​ 3 - 5 years Leasehold improvements ​ Lesser of lease terms or estimated useful lives of the assets ​ Repair and maintenance costs are charged to expense as incurred, whereas the cost of renewals and betterments that extend the useful lives of property, equipment and software are capitalized as additions to the related assets. Retirements, sales and disposals of assets are recorded by removing the cost and accumulated depreciation and amortization from the asset and accumulated depreciation and amortization accounts with any resulting gain or loss reflected in the consolidated statements of comprehensive loss.
Impairment of long-lived assets	Impairment of long-lived assets The Group evaluates the recoverability of its long-lived assets, including fixed assets and intangible assets with finite lives, for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be fully recoverable. When these events occur, the Group measures impairment by comparing the carrying amount of the assets to the estimated undiscounted future cash flows expected to result from the use of the assets and their eventual disposition. If the sum of the expected undiscounted cash flows is less than the carrying amount of the assets, the Group recognizes an impairment loss based on the excess of the carrying amount of the assets over their fair value. Fair value is generally determined by discounting the cash flows expected to be generated by the assets, when the market prices are not readily available. The adjusted carrying amount of the assets is the new cost basis and is depreciated over the assets’ remaining useful lives. Long-lived assets are grouped with other assets and liabilities at the lowest level for which identifiable cash flows are largely independent of the cash flows of other assets and liabilities. No impairment loss was recorded for the years ended December 31, 2021, 2022 and 2023.
Segment reporting	Segment reporting In accordance with ASC 280, Segment Reporting , the Group’s chief operating decision maker (“CODM”) has been identified as the Chief Executive Officer. The Group’s CODM reviews the consolidated results of operations when making decisions about allocating resources and assessing performance of the Group. The Group operates and manages it business as a single segment. No geographical segments are presented as a substantial portion of the Group’s long-lived assets are located in the PRC with the exception of certain laboratory and electronic equipment which are located in the U.S.
Revenue recognition	Revenue recognition At contract inception of collaboration and out-licensing arrangements, the Group analyzes its arrangements to assess whether they are within the scope of ASC 808, Collaborative Arrangements Revenue from Contracts with Customers The Group adopted ASC 606 for all periods presented. To determine revenue recognition for arrangements that an entity determines are within the scope of ASC 606, the entity performs the following five steps: (i) identify the contract(s) with a customer; (ii) identify the performance obligations in the contract; (iii) determine the transaction price, including variable consideration, if any; (iv) allocate the transaction price to the performance obligations in the contract; and (v) recognize revenue when (or as) the entity satisfies a performance obligation. The Group only applies the five-step model to contracts when it is probable that the entity will collect substantially all the consideration to which it is entitled in exchange for the goods or services it transfers to the customer. The Group reviews the contract to determine which performance obligations are distinct and represent a promise to provide distinct goods or services or a series of distinct goods or services as defined by the standard. The Group recognizes as revenue the amount of the transaction price that is allocated to each performance obligation as and when that performance obligation is satisfied. Licenses of Intellectual Property: Research and Development Services : The portion of a transaction price allocated to research and development services performance obligations is deferred and recognized as collaboration revenue over time as delivery or performance of such services occurs. Milestone Payments: At the inception of each arrangement that includes development, commercialization, and regulatory milestone payments, the Group evaluates whether the milestones are considered probable of being reached and to the extent that a significant reversal of cumulative revenue would not occur in future periods, estimates the amount to be included in the transaction price using the most likely amount method. The transaction price is then allocated to each performance obligation on a relative stand-alone selling price basis, for which the Group recognizes revenue as or when the performance obligations under the contract are satisfied. At the end of each subsequent reporting period, the Group re-evaluates the probability of achieving such development milestones and any related constraint, and if necessary, adjust the estimate of the overall transaction price. Any such adjustments are recorded on a cumulative catch-up basis, which would affect revenues and earnings in the period of adjustment. Royalties: Contract assets and contract liabilities When a customer pays consideration before the Group transfers products or services, the Group records its obligation as a contract liability; When the Group satisfies its performance obligations by providing products or services to a customer before the customer pays consideration and before payment is due, the Group recognizes its rights to consideration as a contract asset.
Other operating income, net	Other operating income, net Other operating income, net included a one-time compensation payment from a contract manufacturer in relation to company losses for a preclinical-related outsourcing arrangement.
Research and development expenses	Research and development expenses Elements of research and development expenses primarily include (1) payroll and other related costs of personnel engaged in research and development activities, (2) costs related to pre-clinical testing of the Group’s technologies under development and clinical trials such as payments to contract research organizations (“CRO”) and contract manufacturing organizations (“CMO”), investigators and clinical trial sites that conduct the clinical studies; (3) costs to develop the product candidates, including raw materials and supplies, product testing, depreciation and amortization, and facility related expenses, and (4) other research and development expenses. Research and development costs are expensed as incurred when the related research and development services are provided to the Group and the resulting assets, if any, have no alternative future uses. As of December 31, 2022 and 2023, the Group had several ongoing clinical studies in various clinical trial stages. The contracts with CRO and CMO are generally cancellable, with notice, at the Group’s option. The Group did not record any accrued expenses related to cancellation of CRO or CMO contracts as of December 31, 2022 or 2023 as the Group did not have any plan to cancel the existing CRO or CMO contracts.
Government subsidies	Government subsidies Government subsidies primarily consist of financial subsidies received from provincial and local governments for operating a business in their jurisdictions and compliance with specific policies promoted by the governments. The Group’s PRC based subsidiary received government subsidies from certain local government. The Group’s government subsidies consist of specific subsidies and other subsidies. Specific subsidies are subsidies that the local government has set certain conditions for the subsidies. Other subsidies are the subsidies that the local government has not set any conditions and are not tied to future trends or performance of the Group, receipt of such subsidy income is not contingent upon any further actions or performance of the Group and the amounts do not have to be refunded under any circumstances. These specific subsidies are recorded as other non-current liabilities upon receipt and are recognized as other income when the conditions are met. Other subsidies are recognized as other income upon receipt as further performance by the Group is not required. In addition, the Group’s Australian subsidiary received research and development tax incentive from the Australian Taxation Office in 2021, 2022 and 2023. The tax incentive was recognized as other income upon receipt as the incentive was not dependent upon having a tax liability and further performance by the Group was not required. Government subsidies of US $1.4 million, US $2.1 million and US $1.5 million were received and recognized as other income during the years ended December 31, 2021, 2022 and 2023, respectively.
Leases	Leases In accordance with ASC 842 adopted on January 1, 2022, the Group determines if an arrangement is or contains a lease at inception. Operating leases are included in operating lease right-of-use (“ROU”) assets and lease liabilities on the consolidated balance sheet. Lease liabilities that become due within one year of the balance sheet date are classified as current liabilities. The Group does not have any finance leases since the adoption date. ROU assets represent the right to use an underlying asset for the lease term and lease liabilities represent the obligation to make lease payments arising from the lease. ROU assets and lease liabilities are calculated as the present value of the lease payments not yet paid. As the rate implicit in the Group’s leases is not typically readily available, the Group uses an incremental borrowing rate based on the information available at the lease commencement date in determining the present value of lease payments. This incremental borrowing rate reflects the fixed rate at which the Group could borrow the amount of the lease payments in the same currency, for a similar term, in a similar economic environment. ROU assets include any lease prepayments and are reduced by lease incentives. Operating lease expense for lease payments is recognized on a straight-line basis over the lease term. Lease terms are based on the non-cancelable term of the lease and may contain options to extend the lease when it is reasonably certain that the Group will exercise that option. The Group has elected to adopt the following lease policies in conjunction with the adoption of ASU 2016-02: (i) elect for each lease not to separate non-lease components from lease components and instead to account for each separate lease component and the non-lease components associated with that lease component as a single lease component; (ii) for leases that have lease terms of 12 months or less and does not include a purchase option that is reasonably certain to exercise, the Group elected not to apply ASC 842 recognition requirements; and (iii) the Group elected to apply the package of practical expedients for existing arrangements entered into prior to January 1, 2022 to not reassess (a) whether an arrangement is or contains a lease, (b) the lease classification.
Comprehensive income (loss)	Comprehensive income (loss) Comprehensive income (loss) is defined as the changes in equity of the Group during a period from transactions and other events and circumstances excluding transactions resulting from investments by shareholders and distributions to shareholders. Accumulated other comprehensive income (loss) of the Group includes foreign currency translation adjustments related to the Group and its subsidiaries whose functional currency is not US$.
Income taxes	Income taxes The Group follows the liability method of accounting for income taxes in accordance with ASC 740, Income Taxes The Group evaluates its uncertain tax positions using the provisions of ASC 740, which prescribes a recognition threshold that a tax position is required to meet before being recognized in the consolidated financial statements. The Group recognizes in the consolidated financial statements the benefit of a tax position which is “more likely than not” to be sustained under examination based solely on the technical merits of the position assuming a review by tax authorities having all relevant information. Tax positions that meet the recognition threshold are measured using a cumulative probability approach, at the largest amount of tax benefit that has a greater than fifty percent likelihood of being realized upon settlement. It is the Group’s policy to recognize interest and penalties related to unrecognized tax benefits, if any, as a component of income tax expense.
Borrowings	Borrowings Borrowings are recognized initially at fair value, net of transaction costs incurred. Borrowings are subsequently stated at amortized cost; any difference between the proceeds (net of transaction costs) and the redemption value is recognized in the consolidated statements of comprehensive loss over the period of the borrowings using the effective interest method.
Share-based compensation	Share-based compensation The Company grants restricted shares and stock options to eligible employees and nonemployees and accounts for share-based compensation in accordance with ASC 718, Compensation—Stock Compensation Share-based compensation awards are measured at the grant date fair value of the awards and recognized as expenses (a) immediately at the grant date if no vesting conditions are required; (b) for share-based awards granted with only service conditions, using the straight-line method over the vesting period; or (c) for share-based awards granted with service conditions and performance conditions, using the graded vesting method over the vesting period if and when the Company concludes that it is probable that the performance conditions will be achieved. A change in any of the terms or conditions of share-based awards is accounted for as a modification of the awards. The Group calculates incremental compensation expense of a modification as the excess of the fair value of the modified awards over the fair value of the original awards immediately before its terms are modified at the modification date. For vested awards, the Group recognizes incremental compensation cost in the period when the modification occurs. For awards not being fully vested, the Group recognizes the sum of the incremental compensation expense and the remaining unrecognized compensation expense for the original awards over the remaining requisite service period after modification.
Net loss per share	Net loss per share In accordance with ASC 260, Earnings Per Share , basic net loss per share is computed by dividing net loss attributable to ordinary shareholders by the weighted average number of unrestricted ordinary shares outstanding during the year using the two-class method. Under the two-class method, net loss is allocated between ordinary shares and other participating securities based on dividends declared (or accumulated) and participating rights in undistributed earnings as if all the earnings for the reporting period had been distributed. Diluted net loss per share is calculated by dividing net loss attributable to ordinary shareholders, as adjusted for the effect of dilutive ordinary equivalent shares, if any, by the weighted average number of ordinary and dilutive ordinary equivalent shares outstanding during the period. Ordinary equivalent shares include ordinary shares issuable upon the exercise of share options, using the treasury stock method. Ordinary share equivalents are excluded from the computation of diluted earnings per share if their effects are anti-dilutive. For the periods presented herein, the computation of basic net loss per share using the two-class method is not applicable as the Group does not have participating securities that have contractual rights and obligations to share in the losses of the Group.
Employee defined contribution plan	Employee defined contribution plan As stipulated by the regulations of the PRC, full-time employees of the Group are entitled to staff welfare benefits including medical care, welfare subsidies, unemployment insurance and pension benefits through a PRC government-mandated multi-employer defined contribution plan. The Group is required to accrue for these benefits based on certain percentages of the qualified employees’ salaries. The Group is required to make contributions to the plans out of the amounts accrued. The PRC government is responsible for the medical benefits and the pension liability to be paid to these employees and the Group’s obligations are limited to the amounts contributed. The Group has no further payment obligations once the contributions have been paid. The Group recorded employee benefit expenses of US$2,223,493, US$2,984,251 and US$2,584,392 for the years ended December 31, 2021, 2022 and 2023, respectively.
Concentration of risks	Concentration of risks Concentration of credit risk As of December 31, 2022 and 2023, the amount of cash and cash equivalents of US$8,617,157 and US$6,538,253 respectively, were held at major financial institutions located in Mainland China, and US$135,141,521 and US$103,396,004,respectively, were deposited with major financial institutions located outside of Mainland China. Management believes that these financial institutions are of high credit quality and continually monitors the credit worthiness of these financial institutions. Accounts receivable, if any, is typically unsecured and denominated in US$ and/or RMB and is derived from revenues earned from customers. The Group manages credit risk of accounts receivable through ongoing monitoring of the outstanding balances. Concentration of suppliers For the year ended December 31, 2021 and 2022, a significant portion of the Group’s research and development services were purchased from one supplier group, who collectively accounted for 18.5%, and 34.1% of the Group’s total research and development services purchases, respectively. For the year ended December 31, 2023, there were no suppliers who collectively accounted for more than 10% of the Group’s total research and development services. Business and economic risk The Group believes that changes in any of the following areas could have a material adverse effect on the Group’s future consolidated financial position, results of operations or cash flows: changes in the overall demand for services; competitive pressures due to new entrants; advances and new trends in new technologies and industry standards; changes in certain strategic relationships; regulatory considerations and risks associated with the Group’s ability to attract employees necessary to support its growth. The Group’s operations could also be adversely affected by significant political, regulatory, economic and social uncertainties in the PRC. Foreign currency exchange rate risk A significant portion of the Group’s businesses are transacted in RMB, which is not a freely convertible currency. On January 1, 1994, the PRC government abolished the dual rate system and introduced a single rate of exchange as quoted daily by the PBOC. However, the unification of the exchange rates does not imply that the RMB may be readily convertible into US$ or other foreign currencies. All foreign exchange transactions continue to take place either through the PBOC or other banks authorized to buy and sell foreign currencies at the exchange rates quoted by the PBOC. Approval of foreign currency payments by the PBOC or other institutions requires submitting a payment application form together with suppliers’ invoices, shipping documents and signed contracts. From July 21, 2005, the RMB is permitted to fluctuate within a narrow and managed band against a basket of certain foreign currencies. For U.S. dollar against RMB, there was appreciation of approximately 9.24% in the year ended December 31, 2022 and appreciation of approximately 1.70% in the year ended December 31, 2023, respectively. It is difficult to predict how market forces or PRC or U.S. government policy may impact the exchange rate between the RMB and the U.S. dollar in the future. The functional currency and the reporting currency of the Company are the US$. However, the Group incurs portions of our expenses, and derives revenues, in currencies other than US$, in particular, the RMB. Any significant fluctuation of the valuation of RMB may materially affect the Group’s cash flows, expenses, losses and financial position, and the value of any dividends payable on the American Depositary Shares in US$.
Recently issued accounting pronouncements	Recently issued accounting pronouncements The Group is an emerging growth company (“EGC”) as defined by the Jumpstart Our Business Startups Act (“JOBS Act”). The JOBS Act provides that an EGC can take advantage of extended transition periods for complying with new or revised accounting standards. This allows an EGC to delay adoption of certain accounting standards until those standards would otherwise apply to private companies. The Group elected to take advantage of the extended transition periods. However, this election will not apply should the Group cease to be classified as an EGC. New and amended standards adopted by the Group In June 2016, the FASB issued ASU No. 2016-13, Financial Instruments—Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments New and amended standards not yet adopted by the Group In August 2020, FASB issued ASU 2020-06, Debt—Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging—Contracts in Entity’s Own Equity (Subtopic 815-40): Accounting for Convertible Instruments and Contracts in an Entity’s Own Equity Debt—Debt with Conversion and Other Options In November 2023, FASB issued ASU 2023-07, Segment Reporting (Topic 280), Improvements to Reportable Segment Disclosures, which improves the disclosures about a public entity’s reportable segments and address requests from investors for additional, more detailed information about a reportable segment’s expenses. The standard shall be applied retrospectively to all prior periods presented in the financial statements. The standard is effective for fiscal years beginning after December 15, 2023. The Group has evaluated the impact of this accounting standard update on its consolidated financial statements and assessed the impact of the adoption to be immaterial. In December 2023, FASB issued ASU 2023-09, Income Taxes (Topic 740), Improvements to Income Tax Disclosures, which enhances the transparency and decision usefulness of income tax disclosures. The standard is effective for public entities for annual periods beginning after December 15, 2024. For entities other than public business entities, the amendments are effective for annual periods beginning after December 15, 2025. The standard allows the amendments to be applied the standard on a prospective basis or a retrospective basis. The Group has evaluated the impact of this accounting standard update on its consolidated financial statements and assessed the impact of the adoption to be immaterial.

ORGANIZATION AND BASIS OF PRE_2

ORGANIZATION AND BASIS OF PRESENTATION (Tables)	12 Months Ended
	Dec. 31, 2023
ORGANIZATION AND BASIS OF PRESENTATION
Summary of principal subsidiaries	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Percentage of legal ​ ​ ​ ​ Date of ​ Place of ​ ownership ​ ​ Entity incorporation incorporation by the Company Principal activities Adagene (Hong Kong) Limited ​ December 12, 2011 Hong Kong 100 % Investment holding, and research and development of innovative medicines Adagene Incorporated ​ September 20, 2017 The United States of America 100 % Research and development of innovative medicines Adagene (Suzhou) Limited ​ February 28, 2012 The People’s Republic of China (“PRC” or “China”) 100 % Research and development of innovative medicines Adagene Australia PTY Ltd. ​ May 30, 2018 ​ Australia ​ 100 % Research and development of innovative medicines Adagene PTE. Ltd. ​ March 27, 2020 ​ Singapore ​ 100 % Research and development of innovative medicines Adagene AG ​ August 31, 2020 Switzerland 100 % Research and development of innovative medicines Adagene Project C1 PTE. Ltd. ​ March 25, 2022 Singapore 100 % Research and development of innovative medicines ​

SUMMARY OF SIGNIFICANT ACCOUN_3

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Tables)	12 Months Ended
	Dec. 31, 2023
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Summary of estimated useful lives of property, equipment and software	​ ​ ​ ​ Category Estimated Useful Life Machinery and laboratory equipment ​ 5 years Vehicles ​ 4 years Furniture and tools ​ 3 - 5 years Electronic equipment ​ 3 years Computer software ​ 3 - 5 years Leasehold improvements ​ Lesser of lease terms or estimated useful lives of the assets

PREPAYMENTS AND OTHER CURRENT_2

PREPAYMENTS AND OTHER CURRENT ASSETS (Tables)	12 Months Ended
	Dec. 31, 2023
PREPAYMENTS AND OTHER CURRENT ASSETS
Summary of prepayments and other current assets	​ ​ ​ ​ ​ ​ ​ ​ As of December 31, ​ 2022 2023 ​ ​ US$ ​ US$ Prepayments 1,161,910 591,383 Deposits (a) 2,970,421 1,790,637 Others 804,992 905,425 ​ 4,937,323 3,287,445 Note (a): The deposits represented the amounts that the Group paid to its CRO vendors for various outsourced research and development programs according to the terms of respective CRO agreements. The Group expects to recover the deposits if the programs fail or the agreements are cancelled.

PROPERTY, EQUIPMENT AND SOFTW_2

PROPERTY, EQUIPMENT AND SOFTWARE, NET (Tables)	12 Months Ended
	Dec. 31, 2023
PROPERTY, EQUIPMENT AND SOFTWARE, NET
Summary of property, equipment and software	​ ​ ​ ​ ​ ​ ​ ​ As of December 31, ​ 2022 2023 ​ ​ US$ ​ US$ Machinery and laboratory equipment ​ 5,293,386 5,201,479 Leasehold improvements ​ 1,055,271 1,037,675 Electronic equipment ​ 1,863,963 1,818,352 Furniture and tools ​ 29,684 42,821 Vehicles ​ 80,266 78,928 Software ​ 369,698 363,943 Total property, equipment and software ​ 8,692,268 8,543,198 Less: accumulated depreciation and amortization ​ (5,909,305) (6,708,077) Net book value ​ 2,782,963 1,835,121

ACCRUALS AND OTHER CURRENT LI_2

ACCRUALS AND OTHER CURRENT LIABILITIES (Tables)	12 Months Ended
	Dec. 31, 2023
ACCRUALS AND OTHER CURRENT LIABILITIES
Summary of accrued liabilities and other current liabilities	​ ​ ​ ​ ​ ​ ​ ​ As of December 31, ​ 2022 2023 ​ ​ US$ ​ US$ Professional service fees ​ 1,647,490 1,194,199 Payroll and related liabilities ​ 1,104,365 ​ 1,177,301 Other taxes and surcharge ​ 349,039 510,259 Others ​ 111,915 119,749 ​ 3,212,809 3,001,508 ​

BORROWINGS (Tables)

BORROWINGS (Tables)	12 Months Ended
	Dec. 31, 2023
BORROWINGS
Schedule of borrowings	​ ​ ​ ​ ​ ​ ​ ​ As of December 31, ​ 2022 2023 ​ ​ US$ ​ US$ Current ​ ​ ​ Short-term borrowings: ​ ​ ​ Bank loans ​ 10,768,745 4,235,673 Current portion of long-term borrowings ​ 2,850,128 4,161,549 Total current borrowings ​ 13,618,873 8,397,222 Non-Current ​ ​ ​ Long-term borrowings: ​ ​ ​ Bank loans ​ 14,146,541 13,540,034 Total non-current borrowings ​ 14,146,541 13,540,034 Total borrowings ​ 27,765,414 21,937,256
Schedule of future maturities of short-term borrowings and long-term borrowings	Future principal maturities of short-term borrowings and long-term borrowings as of December 31, 2023 were as follows: ​ ​ ​ ​ ​ ​ As of December 31, ​ ​ 2023 ​ US$ 2024 ​ 8,397,222 2025 ​ 13,116,467 2026 ​ 423,567 ​ ​ 21,937,256 ​

CONVERTIBLE REDEEMABLE PREFER_2

CONVERTIBLE REDEEMABLE PREFERRED SHARES (Tables)	12 Months Ended
	Dec. 31, 2023
CONVERTIBLE REDEEMABLE PREFERRED SHARES
Schedule of Company's Preferred Shares activities	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Preferred Shares Series A-1 Series A-2 Series B Series C-1 Series C-2 Series C-3 Total ​ ​ US$ ​ US$ ​ US$ ​ US$ ​ US$ ​ US$ ​ US$ Balance as of December 31, 2020 ​ 5,473,957 3,000,000 27,999,995 48,975,456 18,999,999 50,000,000 154,449,407 Accretion of Series C-1 Preferred Shares to redemption value ​ — ​ — ​ — ​ 28,553 ​ — ​ — ​ 28,553 Conversion of Preferred Shares to Ordinary Shares ​ (5,473,957) (3,000,000) (27,999,995) (49,004,009) (18,999,999) (50,000,000) (154,477,960) Balance as of December 31, 2021 ​ — — — — — — — ​

SHARE-BASED COMPENSATION (Table

SHARE-BASED COMPENSATION (Tables)	12 Months Ended
	Dec. 31, 2023
SHARE-BASED COMPENSATION
Summary of stock option activity	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted ‑ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Average ​ Weighted ​ ​ ​ ​ ​ ​ Weighted ‑ ​ Grant ​ Average ​ ​ ​ ​ ​ ​ Average ​ Date ​ Remaining ​ Aggregate ​ ​ Number of ​ Exercise ​ Fair ​ Contractual ​ Intrinsic ​ Options Price Value Term Value ​ ​ ​ ​ US$ per ​ US$ per ​ ​ ​ ​ ​ ​ ​ ​ option ​ option ​ Years ​ US$ Outstanding at December 31, 2020 ​ 3,294,467 1.75 6.65 8.78 33,410,968 Granted ​ 1,894,119 12.31 8.39 — — Exercised ​ (233,958) 0.99 5.13 — — Forfeited ​ (145,550) ​ 3.02 ​ 7.71 ​ — ​ — Outstanding at December 31, 2021 ​ 4,809,078 ​ 5.91 ​ 7.38 ​ 8.68 ​ 2,619,574 Granted ​ 2,640,598 ​ 3.28 ​ 2.13 ​ — ​ — Exercised ​ (197,975) ​ 2.08 ​ 6.95 ​ — ​ — Forfeited ​ (964,789) 6.75 7.57 — — Outstanding at December 31, 2022 ​ 6,286,912 4.80 5.16 8.44 94,990 Granted ​ 3,442,500 ​ 1.14 ​ 0.72 ​ — ​ — Exercised ​ (10,000) ​ 0.55 ​ 5.72 ​ — ​ — Forfeited ​ (952,530) ​ 4.59 ​ 3.45 ​ — ​ — Outstanding at December 31, 2023 ​ 8,766,882 ​ 3.39 ​ 3.60 ​ 8.24 ​ 2,011,843 Vested and expected to vest at December 31, 2023 ​ 8,766,882 ​ 3.39 ​ 3.60 ​ 8.24 ​ 2,011,843 Exercisable at December 31, 2022 ​ 2,070,533 ​ 6.35 ​ 6.87 ​ 7.62 ​ 55,880 Exercisable at December 31, 2023 ​ 2,448,076 ​ 5.79 ​ 6.64 ​ 6.75 ​ 207,499
Summary of assumptions used to estimate the fair value of the share options granted	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ For the years ended ​ ​ December 31, ​ 2021 2022 2023 Risk‑free interest rate 1.11% - 1.67% ​ 1.92% - 4.25% ​ 3.38% - 4.86% Dividend yield 0% ​ 0% ​ 0% Expected volatility range 73.1% - 75.5% ​ 74.2% - 74.9% ​ 72.6% - 73.1% Exercise multiple 2.2 - 2.8 ​ 2.2 - 2.8 ​ 2.2 - 2.8 Contractual life 10 years ​ 10 years ​ 10 years
Summary of total share based compensation expenses recognized	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ For the years ended December 31, ​ 2021 2022 2023 ​ ​ US$ ​ US$ ​ US$ Research and development expenses 13,582,746 7,227,298 4,860,548 Administrative expenses 5,096,912 3,292,984 2,411,152 Total share‑based compensation expenses 18,679,658 10,520,282 7,271,700 ​

INCOME TAX EXPENSE (Tables)

INCOME TAX EXPENSE (Tables)	12 Months Ended
	Dec. 31, 2023
INCOME TAX EXPENSE
Schedule of components of income tax expense	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ For the years ended December 31, ​ 2021 2022 2023 ​ ​ US$ ​ US$ ​ US$ Current: ​ ​ ​ ​ ​ ​ U.S. ​ ​ ​ ​ ​ ​ Federal 1,290,009 672,064 1,502,796 State and local 367,441 (168,846) 188,612 Total current 1,657,450 503,218 1,691,408 Deferred: ​ U.S. ​ ​ ​ ​ ​ ​ Federal 96,804 (96,804) — State and local (52,641) 52,641 — Total deferred 44,163 (44,163) — Income tax expense 1,701,613 459,055 1,691,408
Schedule of reconciliation between the income tax expense and the actual provision	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ For the years ended December 31, ​ 2021 2022 2023 ​ ​ US$ ​ US$ ​ US$ Loss before income tax (71,476,322) (79,512,792) (17,254,962) ​ PRC statutory income tax rate ​ 25 % 25 % 25 % Income tax credit computed at PRC statutory income tax rate ​ (17,869,081) (19,878,198) (4,313,740) ​ Impact of PRC preferential income tax rate as qualified TASE ​ 7,147,633 ​ 7,951,279 ​ 1,725,496 ​ Difference in income tax rates of overseas entities ​ 10,549,985 ​ 10,560,029 ​ (1,012,031) ​ Research and development super-deduction (a) ​ (569,016) (1,724,740) (693,340) ​ Research and development tax credits ​ — ​ (569,575) ​ (668,854) ​ Non-deductible expenses ​ 1,054 3,695 7,241 ​ Foreign derived intangible income deduction ​ — ​ (487,183) ​ (394,979) ​ Changes in valuation allowance ​ 2,277,418 4,517,358 7,064,573 ​ State tax ​ 291,500 ​ 76,127 ​ (22,363) ​ Others ​ (127,880) ​ 10,263 ​ (595) ​ Income tax expense ​ 1,701,613 ​ 459,055 ​ 1,691,408 ​ Note (a): Due to the impacts of research and development super-deduction, the Group’s subsidiary, Adagene (Suzhou) Limited, did not have any income taxes for the years ended December 31, 2021, and 2022.
Schedule of tax effects of temporary differences that give rise to the deferred tax balances	​ ​ ​ ​ ​ ​ ​ ​ As of December 31, ​ 2022 2023 ​ ​ US$ ​ US$ Deferred tax assets: ​ ​ ​ Net operating loss carry forward ​ 8,217,976 15,413,070 Tax credit carry forward ​ 391,843 ​ 1,077,073 Capitalized research and development expenses ​ 756,197 ​ — Capitalized inventory ​ 94,954 ​ 72,402 Unrealized foreign exchange gain/losses ​ 116,238 ​ 67,453 Accrued expenses ​ 29,702 ​ — Amortization of right-of-use assets and interest of lease liabilities ​ 546 ​ 676 Gross deferred tax assets ​ 9,607,456 16,630,674 Less: valuation allowance ​ (9,524,497) (16,589,070) Deferred tax assets ​ 82,959 41,604 ​ ​ ​ ​ ​ Deferred tax liabilities: ​ ​ ​ ​ Depreciation and amortization of property, equipment and software ​ (82,959) ​ (41,604) Deferred tax liabilities ​ (82,959) (41,604) Total deferred tax liabilities, net ​ — —
Schedule of movement of the valuation allowance	​ ​ ​ ​ ​ ​ ​ ​ ​ 2021 2022 2023 ​ ​ US$ ​ US$ ​ US$ Balance as of January 1 2,729,721 5,007,139 9,524,497 Addition 2,277,418 4,517,358 7,064,573 Balance as of December 31 5,007,139 9,524,497 16,589,070

NET LOSS PER SHARE (Tables)

NET LOSS PER SHARE (Tables)	12 Months Ended
	Dec. 31, 2023
NET LOSS PER SHARE
Schedule of basic and diluted net loss per share	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ For the Year Ended December 31, ​ ​ 2021 ​ 2022 ​ 2023 ​ US$ US$ US$ Numerator: Net loss attributable to Adagene Inc.’s shareholders (73,177,935) (79,971,847) (18,946,370) Accretion of convertible redeemable preferred shares to redemption value (28,553) — — Net loss attributable to ordinary shareholders (73,206,488) (79,971,847) (18,946,370) Denominator: Weighted‑average number of ordinary shares outstanding—basic and diluted 50,032,009 54,135,084 54,737,530 Net Loss per share—basic and diluted (1.46) (1.48) (0.35)
Schedule of potentially dilutive securities that are not included in the calculation of diluted net loss per share	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ For the Year Ended December 31, ​ 2021 2022 2023 Incremental shares on share options and share grant 1,739,882 530,298 52,942 ​

RELATED PARTY TRANSACTIONS (Tab

RELATED PARTY TRANSACTIONS (Tables)	12 Months Ended
	Dec. 31, 2023
RELATED PARTY TRANSACTIONS
Schedule of related party transactions	a) Related Parties ​ ​ ​ ​ Name of related parties Relationship Peter Luo Chairman, Chief Executive Officer and a principal shareholder of the Company Certain senior management personnel Management and ordinary shareholders of the Company WuXi AppTec Co., Ltd. (“WuXi AppTec Group”) A principal shareholder of the Company WuXi Biologics (Cayman) Inc. Controlled by the ultimate controlling party of a principal shareholder of the Company ​ b) The Group had the following related party balances as of December 31, 2022 and 2023: ​ ​ ​ ​ ​ ​ ​ ​ As of December 31, ​ ​ 2022 ​ 2023 ​ US$ US$ WuXi AppTec Group 503,941 118,594 WuXi Biologics (Cayman) Inc. 115,491 102,416 Certain senior management personnel. ​ — ​ 1,017 Total amounts due from related parties 619,432 222,027 ​ As of December 31, 2022 and 2023, the amounts due from related parties mainly represented prepayments made for the CRO and CMO services. ​ ​ ​ ​ ​ ​ ​ ​ As of December 31, ​ ​ 2022 ​ 2023 ​ US$ US$ WuXi Biologics (Cayman) Inc. 17,840,876 16,371,593 WuXi AppTec Group 1,482,461 341,716 Certain senior management personnel. ​ — ​ 1,017 Total amounts due to related parties 19,323,337 16,714,326 ​ As of December 31, 2022 and 2023, the amounts due to related parties mainly represented payables for the CRO and CMO services. ​ c) The Group had the following related party transactions during the years ended December 31, 2021, 2022 and 2023: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ For the years ended ​ ​ December 31, ​ ​ 2021 ​ 2022 ​ 2023 ​ US$ US$ US$ Receipt of CRO and CMO services: ​ ​ ​ WuXi Biologics (Cayman) Inc. 12,561,276 27,764,750 1,868,815 WuXi AppTec Group 517,742 7,362,713 787,602 Certain senior management personnel. ​ — ​ — ​ 4,087 ​ 13,079,018 35,127,463 2,660,504 ​

LEASES (Table)

LEASES (Table)	12 Months Ended
	Dec. 31, 2023
LEASES
Summary of information related to operating leases	​ ​ ​ ​ ​ ​ ​ ​ As of December 31, ​ ​ 2022 2023 ​ ​ US$ ​ US$ ​ Assets ​ ​ Operating lease right-of-use assets 191,877 ​ 365,103 ​ Liabilities ​ ​ ​ Current portion of operating lease liabilities 151,983 ​ 195,955 ​ Operating lease liabilities 53,834 ​ 173,660 ​ Weighted average remaining lease term (years) 1.3 ​ 2.1 ​ Weighted average discount rate ​ 4.6 % 4.4 %
Summary of information related to operating lease activity	​ ​ ​ ​ ​ ​ ​ For the Year Ended December 31, ​ ​ 2022 2023 ​ ​ US$ US$ Operating lease rental expense ​ Amortization of right-of-use assets 283,276 ​ 216,305 Expense for short-term leases within 12 months 34,729 ​ 13,514 Interest of lease liabilities 20,259 ​ 12,100 ​ 338,264 ​ 241,919
Summary of maturities of lease liabilities	​ ​ ​ ​ ​ ​ ​ As of December 31, ​ ​ 2022 2023 ​ ​ US$ ​ ​ 2023 157,603 ​ — 2024 54,823 ​ 207,155 2025 ​ — ​ 123,546 2026 ​ — ​ 55,499 Total undiscounted lease payments 212,426 ​ 386,200 Less: imputed interest (6,609) ​ (16,585) Total lease liabilities 205,817 ​ 369,615 ​

ORGANIZATION AND BASIS OF PRE_3

ORGANIZATION AND BASIS OF PRESENTATION (Details)		12 Months Ended
	Feb. 11, 2021 USD ($) $ / shares shares	Dec. 31, 2021 USD ($)	Dec. 31, 2023
ORGANIZATION AND BASIS OF PRESENTATION
Net proceeds | $		$ 149,411,950
IPO | American depositary shares
ORGANIZATION AND BASIS OF PRESENTATION
Share price (in USD per share) | $ / shares	$ 19
Shares issued (in shares) | shares	8,457,100
Net proceeds | $	$ 145,900,000
Number of ordinary shares represented by each ADS	1.25
Underwriters' option | American depositary shares
ORGANIZATION AND BASIS OF PRESENTATION
Shares issued (in shares) | shares	1,103,100
Adagene (Hong Kong) Limited
ORGANIZATION AND BASIS OF PRESENTATION
Percentage of legal ownership by the Company			100%
Adagene Incorporated
ORGANIZATION AND BASIS OF PRESENTATION
Percentage of legal ownership by the Company			100%
Adagene (Suzhou) Limited
ORGANIZATION AND BASIS OF PRESENTATION
Percentage of legal ownership by the Company			100%
Adagene Australia PTY Ltd.
ORGANIZATION AND BASIS OF PRESENTATION
Percentage of legal ownership by the Company			100%
Adagene PTE. Ltd.
ORGANIZATION AND BASIS OF PRESENTATION
Percentage of legal ownership by the Company			100%
Adagene AG
ORGANIZATION AND BASIS OF PRESENTATION
Percentage of legal ownership by the Company			100%
Adagene Project C1 PTE. Ltd.
ORGANIZATION AND BASIS OF PRESENTATION
Percentage of legal ownership by the Company			100%

SUMMARY OF SIGNIFICANT ACCOUN_4

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Nonrecurring (Details) - Nonrecurring basis - USD ($)	Dec. 31, 2023	Dec. 31, 2022
Fair value measurements
Financial assets	$ 0	$ 0
Financial liabilities	$ 0	$ 0

SUMMARY OF SIGNIFICANT ACCOUN_5

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Property, equipment and software (Details)	Dec. 31, 2023
Machinery and laboratory equipment
PROPERTY, EQUIPMENT AND SOFTWARE, NET
Estimated Useful Life	5 years
Vehicles
PROPERTY, EQUIPMENT AND SOFTWARE, NET
Estimated Useful Life	4 years
Furniture and tools | Minimum
PROPERTY, EQUIPMENT AND SOFTWARE, NET
Estimated Useful Life	3 years
Furniture and tools | Maximum
PROPERTY, EQUIPMENT AND SOFTWARE, NET
Estimated Useful Life	5 years
Electronic equipment
PROPERTY, EQUIPMENT AND SOFTWARE, NET
Estimated Useful Life	3 years
Software | Minimum
PROPERTY, EQUIPMENT AND SOFTWARE, NET
Estimated Useful Life	3 years
Software | Maximum
PROPERTY, EQUIPMENT AND SOFTWARE, NET
Estimated Useful Life	5 years

SUMMARY OF SIGNIFICANT ACCOUN_6

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Impairment of long lived assets to Employee defined contribution plan (Details) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Impairment of long lived assets
Impairment loss	$ 0	$ 0	$ 0
Employee defined contribution plan
Employee benefit expenses	$ 2,584,392	$ 2,984,251	$ 2,223,493

SUMMARY OF SIGNIFICANT ACCOUN_7

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Concentration of credit risk (Details)	12 Months Ended
	Dec. 31, 2023 USD ($) item	Dec. 31, 2022 USD ($) item	Dec. 31, 2021 item
Concentration of risks
Operating lease right-of-use assets	$ 365,103	$ 191,877
Operating lease liabilities	369,615	205,817
Concentration of credit risk | Cash and cash equivalents and short-term investments | Mainland of China
Concentration of risks
Cash and cash equivalents	6,538,253	8,617,157
Concentration of credit risk | Cash and cash equivalents and short-term investments | Outside the mainland of China
Concentration of risks
Cash and cash equivalents	$ 103,396,004	$ 135,141,521
Concentration of suppliers | Research and development services purchased
Concentration of risks
Number of major supplier | item	0	1	1
Concentration of suppliers | Research and development services purchased | One supplier
Concentration of risks
Concentration risk percentage		34.10%	18.50%
Concentration of suppliers | Research and development services purchased | No supplier
Concentration of risks
Concentration risk percentage	10%

SUMMARY OF SIGNIFICANT ACCOUN_8

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Foreign currency exchange rate risk (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
Depreciation of foreign currency (as a percent)	1.70%	9.24%
Government subsidies received	$ 1.5	$ 2.1	$ 1.4

PREPAYMENTS AND OTHER CURRENT_3

PREPAYMENTS AND OTHER CURRENT ASSETS (Details) - USD ($)	Dec. 31, 2023	Dec. 31, 2022
PREPAYMENTS AND OTHER CURRENT ASSETS
Prepayments	$ 591,383	$ 1,161,910
Deposits	1,790,637	2,970,421
Others	905,425	804,992
Prepayments and other current assets	$ 3,287,445	$ 4,937,323

PROPERTY, EQUIPMENT AND SOFTW_3

PROPERTY, EQUIPMENT AND SOFTWARE, NET (Details) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
PROPERTY, EQUIPMENT AND SOFTWARE, NET
Total property, equipment and software	$ 8,543,198	$ 8,692,268
Less: accumulated depreciation and amortization	(6,708,077)	(5,909,305)
Net book value	1,835,121	2,782,963
Depreciation and amortization	980,053	1,145,995	$ 1,125,032
Machinery and laboratory equipment
PROPERTY, EQUIPMENT AND SOFTWARE, NET
Total property, equipment and software	5,201,479	5,293,386
Leasehold improvements
PROPERTY, EQUIPMENT AND SOFTWARE, NET
Total property, equipment and software	1,037,675	1,055,271
Electronic equipment
PROPERTY, EQUIPMENT AND SOFTWARE, NET
Total property, equipment and software	1,818,352	1,863,963
Furniture and tools
PROPERTY, EQUIPMENT AND SOFTWARE, NET
Total property, equipment and software	42,821	29,684
Vehicles
PROPERTY, EQUIPMENT AND SOFTWARE, NET
Total property, equipment and software	78,928	80,266
Software
PROPERTY, EQUIPMENT AND SOFTWARE, NET
Total property, equipment and software	$ 363,943	$ 369,698

ACCRUALS AND OTHER CURRENT LI_3

ACCRUALS AND OTHER CURRENT LIABILITIES (Details) - USD ($)	Dec. 31, 2023	Dec. 31, 2022
Related Party Transaction [Line Items]
Professional service fees	$ 1,194,199	$ 1,647,490
Payroll and related liabilities	1,177,301	1,104,365
Other taxes and surcharge	510,259	349,039
Others	16,714,326	19,323,337
Accruals and other current liabilities	3,001,508	3,212,809
Non-related party
Related Party Transaction [Line Items]
Others	$ 119,749	$ 111,915

BORROWINGS - Components (Detail

BORROWINGS - Components (Details) - USD ($)	Dec. 31, 2023	Dec. 31, 2022
Short term borrowings:
Bank loans	$ 4,235,673	$ 10,768,745
Current portion of long term borrowings	4,161,549	2,850,128
Total current borrowings	8,397,222	13,618,873
Long term borrowings:
Bank loans	13,540,034	14,146,541
Total non current borrowings	13,540,034	14,146,541
Total borrowings	$ 21,937,256	$ 27,765,414

BORROWINGS - Short term borrowi

BORROWINGS - Short term borrowings (Details)	1 Months Ended
	Jul. 31, 2023 CNY (¥)	Mar. 31, 2023 CNY (¥)	Jan. 31, 2023 CNY (¥)	Dec. 31, 2022 CNY (¥)	Jul. 31, 2022 CNY (¥)	Apr. 30, 2022 CNY (¥)	Mar. 31, 2022 CNY (¥)	Aug. 31, 2021 CNY (¥)	Jun. 30, 2021 CNY (¥)	Nov. 30, 2020 CNY (¥)	Sep. 30, 2020 CNY (¥)	Jun. 30, 2020 CNY (¥)	Jul. 31, 2023 USD ($)	Mar. 31, 2023 USD ($)	Jan. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Jul. 31, 2022 USD ($)	Apr. 30, 2022 USD ($)	Mar. 31, 2022 USD ($)	Aug. 31, 2021 USD ($)	Jun. 30, 2021 USD ($)	Nov. 30, 2020 USD ($)	Sep. 30, 2020 USD ($)	Jun. 30, 2020 USD ($)
Borrowings from Bank of Jiangsu Co., Ltd
Short-term debt
Amount borrowed					¥ 20,000,000												$ 2,871,665
Term of the debt					1 year
Interest rate (as a percent)					3.70%												3.70%
Borrowings from Bank of Ningbo Co., Ltd
Short-term debt
Amount borrowed	¥ 10,000,000		¥ 10,000,000								¥ 5,000,000			$ 1,411,891									$ 766,295
Term of the debt		1 year									1 year
Interest rate (as a percent)		3.80%									4.20%			3.80%									4.20%
Borrowings from Agricultural Bank of China Limited
Short-term debt
Amount borrowed								¥ 10,000,000	¥ 9,900,000			¥ 10,000,000			$ 1,411,891					$ 1,568,455	$ 1,552,771			$ 1,532,591
Term of the debt			1 year					1 year	1 year			1 year
Interest rate (as a percent)			3.90%					4.05%	4.05%			4.20%			3.90%					4.05%	4.05%			4.20%
China Merchants Bank Co., Ltd
Short-term debt
Amount borrowed						¥ 20,100,000	¥ 9,900,000			¥ 5,000,000			$ 1,411,891					$ 2,886,024	$ 1,421,474			$ 770,962
Term of the debt	1 year					1 year	1 year			1 year
Interest rate (as a percent)	3.85%					3.70%	3.90%			4.10%			3.85%					3.70%	3.90%			4.10%
China Merchants Bank Co., Ltd., two
Short-term debt
Amount borrowed										¥ 5,000,000												$ 770,962
Term of the debt										1 year
Interest rate (as a percent)										4.10%												4.10%
China Construction Bank Corporation
Short-term debt
Amount borrowed				¥ 25,000,000												$ 3,589,582
Term of the debt				1 year
Interest rate (as a percent)				3.65%												3.65%
China Everbright Bank Corporation [Member]
Short-term debt
Amount borrowed		¥ 10,000,000

BORROWINGS - Long term borrowin

BORROWINGS - Long term borrowings (Details)	12 Months Ended
	Dec. 31, 2023 USD ($)	Dec. 31, 2023 CNY (¥)	Dec. 31, 2022 USD ($)	Dec. 31, 2022 CNY (¥)	Dec. 31, 2021 USD ($)	Dec. 31, 2021 CNY (¥)	Dec. 31, 2020 USD ($)	Dec. 31, 2020 CNY (¥)	Dec. 31, 2019 USD ($)	Dec. 31, 2019 CNY (¥)	Dec. 31, 2023 CNY (¥)	Sep. 30, 2023 USD ($)	Sep. 30, 2023 CNY (¥)	Aug. 31, 2023 USD ($)	Aug. 31, 2023 CNY (¥)	Apr. 30, 2023 USD ($)	Apr. 30, 2023 CNY (¥)	Dec. 31, 2022 CNY (¥)	Nov. 30, 2022 USD ($)	Nov. 30, 2022 CNY (¥)	Aug. 31, 2022 USD ($)	Aug. 31, 2022 CNY (¥)	May 31, 2022 USD ($)	May 31, 2022 CNY (¥)	Dec. 31, 2021 CNY (¥)	Sep. 30, 2021 USD ($)	Sep. 30, 2021 CNY (¥)	Sep. 30, 2020 USD ($)	Sep. 30, 2020 CNY (¥)	Jun. 30, 2019 USD ($)	Jun. 30, 2019 CNY (¥)	Feb. 28, 2019 USD ($)	Feb. 28, 2019 CNY (¥)
Debt instrument
Amount repaid	$ 13,506,221		$ 4,353,588		$ 5,089,717
Current portion of long-term borrowings	4,161,549		2,850,128
Borrowings from Shanghai Pudong Development Bank Co., Ltd., one
Debt instrument
Amount borrowed																																$ 1,076,874	¥ 7,500,000
Term of the debt																																3 years	3 years
Interest rate (as a percent)																																5.46%	5.46%
Amount repaid			358,958	¥ 2,500,000	484,594	¥ 3,375,000	$ 179,479	¥ 1,250,000	$ 53,844	¥ 375,000
Current portion of long-term borrowings					358,958																				¥ 2,500,000
Borrowings from Shanghai Pudong Development Bank Co., Ltd., two
Debt instrument
Amount borrowed																														$ 861,500	¥ 6,000,000
Term of the debt																														3 years	3 years
Interest rate (as a percent)																														5.23%	5.23%
Amount repaid			287,167	2,000,000	387,675	2,700,000	$ 143,583	¥ 1,000,000	$ 43,075	¥ 300,000
Current portion of long-term borrowings					287,167																				¥ 2,000,000
Borrowings from Shanghai Pudong Development Bank Co., Ltd., three
Debt instrument
Amount borrowed																												$ 2,329,620	¥ 16,500,000
Term of the debt																												3 years	3 years
Interest rate (as a percent)																												4.27%	4.27%
Amount repaid			543,578	3,850,000	$ 232,962	¥ 1,650,000
Current portion of long-term borrowings			1,553,080									$ 1,553,080	¥ 11,000,000					¥ 11,000,000
Borrowings from Shanghai Pudong Development Bank Co., Ltd., four
Debt instrument
Amount borrowed																										$ 1,200,107	¥ 8,500,000
Term of the debt																										3 years	3 years
Interest rate (as a percent)																										4.05%	4.05%
Amount repaid	120,011	¥ 850,000	60,005	425,000
Current portion of long-term borrowings	1,020,092		120,011								¥ 7,225,000							850,000
Borrowings from Shanghai Pudong Development Bank Co., Ltd., five
Debt instrument
Amount borrowed																							$ 2,823,782	¥ 20,000,000
Term of the debt																							3 years	3 years
Interest rate (as a percent)																							4%	4%
Amount repaid	211,784	1,500,000	70,595	¥ 500,000
Current portion of long-term borrowings	1,341,297		211,784								9,500,000							1,500,000
Borrowings from Shanghai Pudong Development Bank Co., Ltd., six
Debt instrument
Amount borrowed																					$ 2,823,782	¥ 20,000,000
Term of the debt																					3 years	3 years
Interest rate (as a percent)																					4%	4%
Amount repaid	141,189	1,000,000
Current portion of long-term borrowings	282,378		141,189								2,000,000							1,000,000
Borrowings from Shanghai Pudong Development Bank Co., Ltd., seven
Debt instrument
Amount borrowed																			$ 1,411,891	¥ 10,000,000
Term of the debt																			3 years	3 years
Interest rate (as a percent)																			4%	4%
Amount repaid	70,595	500,000
Current portion of long-term borrowings	141,189		70,595								1,000,000							500,000
Borrowings from Shanghai Pudong Development Bank Co., Ltd., eight
Debt instrument
Amount borrowed																$ 988,324	¥ 7,000,000
Term of the debt																3 years	3 years
Interest rate (as a percent)																3.90%	3.90%
Amount repaid	21,178	150,000
Current portion of long-term borrowings	77,654										550,000
Borrowings from Agricultural Bank of China Limited one
Debt instrument
Amount borrowed																							$ 4,235,673	¥ 30,000,000
Term of the debt																							3 years	3 years
Interest rate (as a percent)																							4%	4%
Amount repaid	423,567	3,000,000
Current portion of long-term borrowings	705,945		423,567								5,000,000							3,000,000
Borrowings from Agricultural Bank of China Limited two
Debt instrument
Amount borrowed																					$ 1,397,772	¥ 9,900,000
Term of the debt																					3 years	3 years
Interest rate (as a percent)																					4%	4%
Amount repaid	141,189	1,000,000
Current portion of long-term borrowings	282,378		141,189								2,000,000							1,000,000
Borrowings from Agricultural Bank of China Limited three
Debt instrument
Amount borrowed																			$ 1,397,772	¥ 9,900,000
Term of the debt																			3 years	3 years
Interest rate (as a percent)																			4%	4%
Amount repaid	141,189	¥ 1,000,000
Current portion of long-term borrowings	282,378		$ 141,189								2,000,000							¥ 1,000,000
Borrowings from Bank of Jiangsu Co., Ltd one
Debt instrument
Amount borrowed														$ 1,411,891	¥ 10,000,000
Term of the debt														18 months	18 months
Interest rate (as a percent)														3.80%	3.80%
Current portion of long-term borrowings	14,119										100,000
Borrowings from Bank of Jiangsu Co., Ltd two
Debt instrument
Amount borrowed												$ 1,411,891	¥ 10,000,000
Term of the debt												18 months	18 months
Interest rate (as a percent)												3.80%	3.80%
Current portion of long-term borrowings	$ 14,119										¥ 100,000

BORROWINGS - Future maturities

BORROWINGS - Future maturities of short term borrowings and long term borrowings (Details) - USD ($)	Dec. 31, 2023	Dec. 31, 2022
BORROWINGS
2024	$ 8,397,222
2025	13,116,467
2026	423,567
Total borrowings	$ 21,937,256	$ 27,765,414

CONVERTIBLE REDEEMABLE PREFER_3

CONVERTIBLE REDEEMABLE PREFERRED SHARES - Narrative (Details) - shares	Dec. 31, 2023	Dec. 31, 2022	Feb. 11, 2021
CONVERTIBLE REDEEMABLE PREFERRED SHARES
Preferred shares issued	0	0
IPO
CONVERTIBLE REDEEMABLE PREFERRED SHARES
Number of shares on conversion of each convertible preferred stock			1

CONVERTIBLE REDEEMABLE PREFER_4

CONVERTIBLE REDEEMABLE PREFERRED SHARES (Details)	12 Months Ended
	Dec. 31, 2021 USD ($)
Increase (Decrease) in Temporary Equity
Beginning balance	$ 154,449,407
Conversion of Preferred Shares to Ordinary Shares	(154,477,960)
Series A-1 convertible redeemable preferred shares
Increase (Decrease) in Temporary Equity
Beginning balance	5,473,957
Conversion of Preferred Shares to Ordinary Shares	(5,473,957)
Series A-2 convertible redeemable preferred shares
Increase (Decrease) in Temporary Equity
Beginning balance	3,000,000
Conversion of Preferred Shares to Ordinary Shares	(3,000,000)
Series B convertible redeemable preferred shares
Increase (Decrease) in Temporary Equity
Beginning balance	27,999,995
Conversion of Preferred Shares to Ordinary Shares	(27,999,995)
Series C-1 convertible redeemable preferred shares
Increase (Decrease) in Temporary Equity
Beginning balance	48,975,456
Accretion of Preferred Shares to redemption value	28,553
Conversion of Preferred Shares to Ordinary Shares	(49,004,009)
Series C-2 convertible redeemable preferred shares
Increase (Decrease) in Temporary Equity
Beginning balance	18,999,999
Conversion of Preferred Shares to Ordinary Shares	(18,999,999)
Series C-3 convertible redeemable preferred shares
Increase (Decrease) in Temporary Equity
Beginning balance	50,000,000
Conversion of Preferred Shares to Ordinary Shares	$ (50,000,000)

SHARE-BASED COMPENSATION (Detai

SHARE-BASED COMPENSATION (Details) - USD ($)

1 Months Ended

9 Months Ended

11 Months Ended

12 Months Ended

Mar. 08, 2022

Jan. 07, 2022

Mar. 16, 2021

Jan. 16, 2021

Nov. 09, 2020

Apr. 30, 2023

Jan. 31, 2023

Dec. 31, 2023

Dec. 22, 2021

Dec. 27, 2022

Dec. 31, 2023

Dec. 31, 2022

Dec. 31, 2021

Dec. 31, 2019

Sep. 30, 2017

Nov. 07, 2015

SHARE-BASED COMPENSATION

Expiration period (in years)

10 years

Share options granted

3,442,500

2,640,598

1,894,119

Exercise price (in USD per share)

$ 13.85

$ 1.14

$ 3.28

$ 12.31

Shares issued upon exercise of share options (in shares)

10,000

197,975

233,958

Total amount

$ 5,500

$ 323,212

$ 226,781

Number of shares surrendered

491,119

Fair value (in USD per option)

$ 7.85

$ 0.72

$ 2.13

$ 8.39

Maximum

SHARE-BASED COMPENSATION

Vesting period (in years)

5 years

Service conditions and Performance conditions

SHARE-BASED COMPENSATION

Share options granted

4,826,906

4,776,906

Employees | Modification of vesting schedules and conditions of share options

SHARE-BASED COMPENSATION

Share options granted

2,060,308

Incremental fair value

$ 2,337,697

Management personnel

SHARE-BASED COMPENSATION

Number of options, vesting schedules and conditions waived

2,375,000

Shares issued upon exercise of share options (in shares)

2,375,000

Total amount

$ 5,197,650

Shares unvested

325,000

325,000

Management personnel | Minimum

SHARE-BASED COMPENSATION

Exercise price (in USD per share)

$ 1.83

Management personnel | Maximum

SHARE-BASED COMPENSATION

Exercise price (in USD per share)

$ 2.26

2015 Plan

SHARE-BASED COMPENSATION

Maximum aggregate number of shares that may be issued

4,336,126

2017 Plan

SHARE-BASED COMPENSATION

Maximum aggregate number of shares that may be issued

6,336,126

2019 Plan

SHARE-BASED COMPENSATION

Maximum aggregate number of shares that may be issued

11,391,131

2021 Plan

SHARE-BASED COMPENSATION

Aggregate ordinary shares reserved for issuance

2,994,000

Incremental percent of shares

5%

2021 Plan | Employees

SHARE-BASED COMPENSATION

Share options granted

69,225

3,442,500

1,303,000

2,640,598

2021 Plan | Employees | Minimum

SHARE-BASED COMPENSATION

Exercise price (in USD per share)

$ 0.94

$ 5.92

$ 0.80

2021 Plan | Employees | Maximum

SHARE-BASED COMPENSATION

Exercise price (in USD per share)

$ 1.33

$ 17.56

$ 5.60

2021 Plan | Management personnel

SHARE-BASED COMPENSATION

Share options granted

99,999

23,734

425,905

SHARE-BASED COMPENSATION - Shar

SHARE-BASED COMPENSATION - Share Option Activities (Details) - USD ($)		12 Months Ended
	Jan. 16, 2021	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Number of Options
Outstanding at the beginning		6,286,912	4,809,078	3,294,467
Granted (in shares)		3,442,500	2,640,598	1,894,119
Exercised (in shares)		(10,000)	(197,975)	(233,958)
Forfeited (in shares)		(952,530)	(964,789)	(145,550)
Outstanding at the end		8,766,882	6,286,912	4,809,078	3,294,467
Vested and expected to vest at the end		8,766,882
Exercisable at the end		2,448,076	2,070,533
Weighted Average Exercise Price
Outstanding at the beginning (in dollars per share)		$ 4.80	$ 5.91	$ 1.75
Granted (in dollars per share)	$ 13.85	1.14	3.28	12.31
Exercised (in dollars per share)		0.55	2.08	0.99
Forfeited (in dollars per share)		4.59	6.75	3.02
Outstanding at the end (in dollars per share)		3.39	4.80	5.91	$ 1.75
Vested and expected to vest at the end (in dollars per share)		3.39
Exercisable at the end (in dollars per share)		5.79	6.35
Weighted Average Grant Date Fair Value
Outstanding at the beginning (in dollars per share)		5.16	7.38	6.65
Granted (in dollars per share)	$ 7.85	0.72	2.13	8.39
Exercised (in dollars per share)		5.72	6.95	5.13
Forfeited (in dollars per share)		3.45	7.57	7.71
Outstanding at the end (in dollars per share)		3.60	5.16	$ 7.38	$ 6.65
Vested and expected to vest at the end (in dollars per share)		3.60
Exercisable at the end (in dollars per share)		$ 6.64	$ 6.87
Weighted Average Remaining Contractual Term and Aggregate Intrinsic Value
Outstanding (in years)		8 years 2 months 26 days	8 years 5 months 8 days	8 years 8 months 4 days	8 years 9 months 10 days
Vested and expected to vest at the end (in years)		8 years 2 months 26 days
Exercisable at the end (in years)		6 years 9 months	7 years 7 months 13 days
Outstanding at the beginning (in dollars)		$ 94,990	$ 2,619,574	$ 33,410,968
Outstanding at the end (in dollars)		2,011,843	94,990	$ 2,619,574	$ 33,410,968
Vested and expected to vest at the end (in dollars)		2,011,843
Exercisable at the end (in dollars)		$ 207,499	$ 55,880

SHARE-BASED COMPENSATION - Sh_2

SHARE-BASED COMPENSATION - Share Option Activities - Narrative (Details) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
SHARE-BASED COMPENSATION
Aggregate fair value of the equity awards vested	$ 6,742,535	$ 11,929,903	$ 13,833,856
Unrecognized employee share based compensation expense	$ 16,658,848
Weighted average period to recognize unrecognized compensation cost (in years)	1 year 7 months 20 days

SHARE-BASED COMPENSATION - Fair

SHARE-BASED COMPENSATION - Fair Value Of Share Options (Details) - $ / shares	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Assumptions used to estimate the fair value
Risk free interest rate, minimum	3.38%	1.92%	1.11%
Risk free interest rate, maximum	4.86%	4.25%	1.67%
Dividend yield	0%	0%	0%
Expected volatility, minimum	72.60%	74.20%	73.10%
Expected volatility, maximum	73.10%	74.90%	75.50%
Exercise multiple, minimum	$ 2.2	$ 2.2	$ 2.2
Exercise multiple, maximum	$ 2.8	$ 2.8	$ 2.8
Contractual life (in years)	10 years	10 years	10 years

SHARE-BASED COMPENSATION - Sh_3

SHARE-BASED COMPENSATION - Share based compensation expenses (Details) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
SHARE-BASED COMPENSATION
Total sharebased compensation expenses	$ 7,271,700	$ 10,520,282	$ 18,679,658
Research and development expenses
SHARE-BASED COMPENSATION
Total sharebased compensation expenses	4,860,548	7,227,298	13,582,746
Administrative expenses
SHARE-BASED COMPENSATION
Total sharebased compensation expenses	$ 2,411,152	$ 3,292,984	$ 5,096,912

COLLABORATION ARRANGEMENTS (Det

COLLABORATION ARRANGEMENTS (Details)	1 Months Ended			12 Months Ended
	Mar. 31, 2022 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2018 CNY (¥)	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2021 CNY (¥)	Aug. 31, 2022 USD ($)	Apr. 30, 2022 USD ($)	Feb. 28, 2021 USD ($)
Collaborative Arrangement and Arrangement Other than Collaborative
Revenues				$ 18,111,491	$ 9,292,724	$ 10,175,258
Guilin Sanjin Pharmaceutical Co., Ltd. License Agreement
Collaborative Arrangement and Arrangement Other than Collaborative
Upfront cash payment received		$ 1,511,168	¥ 10,000,000
Agreed period for not to grant rights associated with antibodies to third parties		3 years	3 years
Dragon Boat Biopharmaceutical (Shanghai) Limited License Agreement
Collaborative Arrangement and Arrangement Other than Collaborative
Agreed period for not to grant rights associated with antibodies to third parties				3 years
Revenues				$ 0	0	620,011	¥ 4,000,000
Milestone payment received						620,011	¥ 4,000,000
ADCT Collaboration Agreement
Collaborative Arrangement and Arrangement Other than Collaborative
Revenues						225,000
Period for reservation of target right				1 year
Other income						100,000
Exelixis Inc Agreement
Collaborative Arrangement and Arrangement Other than Collaborative
Upfront cash payment received					1,100,000	11,000,000
Revenues				$ 9,600,000	0
Milestone payment received				3,000,000
Payment of upfront-refundable fee									$ 1,100,000	$ 11,000,000
Milestone payments receivable based on development and regulatory milestones										127,500,000
Milestone payments receivable based on sales										$ 262,500,000
Accounts receivable, net						3,000,000
Upfront fee received				5,500,000
Milestone fee received				3,000,000
Exelixis Inc Agreement | Delivery of data packages and achievement of initial target milestone
Collaborative Arrangement and Arrangement Other than Collaborative
Revenues				8,500,000		$ 8,500,000
Exelixis Inc Agreement | Delivery of additional masked antibodies
Collaborative Arrangement and Arrangement Other than Collaborative
Revenues				1,100,000
ADCT Material Transfer and Option Agreement
Collaborative Arrangement and Arrangement Other than Collaborative
Revenues					300,000
Payment of upfront-refundable fee								$ 300,000
Sanofi Agreement
Collaborative Arrangement and Arrangement Other than Collaborative
Upfront cash payment received	$ 17,500,000				17,500,000
Revenues				$ 8,507,276	$ 8,992,724
Milestone payments receivable based on development and regulatory milestones	173,500,000
Milestone payments receivable based on sales	$ 450,000,000

INCOME TAX EXPENSE (Details)

INCOME TAX EXPENSE (Details) - USD ($)		12 Months Ended			108 Months Ended
	Jan. 01, 2008	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2023
Income tax rate (as a percent)		25%	25%	25%
Net operating losses		$ 136,672,221			$ 136,672,221
Provision for income taxes		$ 1,691,408	$ 459,055	$ 1,701,613
PRC
Income tax rate (as a percent)	25%
Dividends withholding tax rate		10%
Net operating losses		$ 25,271,118			$ 25,271,118
PRC | TASE
Preferential tax rate (as a percent)	15%
Effective period of TASE certificate (in years)	3 years
PRC | TASE | Adagene (Suzhou) Limited
Preferential tax rate (as a percent)					15%
Hong Kong
Income tax rate (as a percent)		16.50%
Net operating losses		$ 5,744,965			$ 5,744,965
Withholding tax		0			0
Hong Kong | Adagene (Hong Kong) Limited
Assessable profits or earnings		0	0	0
Provision for income taxes		$ 0	0	0
Australia
Income tax rate (as a percent)		30%
Dividends withholding tax rate		30%
Net operating losses		$ 11,094,390			11,094,390
Australia | Adagene Australia PTY Ltd.
Taxable Income		0	0	0
Provision for income taxes		$ 0	$ 0	$ 0
United States
Dividends withholding tax rate		30%
Net operating losses		$ 88,416,478			88,416,478
State income tax rate (as a percent)		21%
California
State income tax rate (as a percent)		8.84%
SWITZERLAND
Income tax rate (as a percent)		8.50%
Dividends withholding tax rate		35%
Net operating losses		$ 4,635,670			4,635,670
SWITZERLAND | Adagene AG
Income tax rate (as a percent)		6.50%
Capital tax rate for Canton of Basel		0.10%
SINGAPORE
Net operating losses		$ 1,509,600			$ 1,509,600

INCOME TAX EXPENSE - Income tax

INCOME TAX EXPENSE - Income tax expense (benefit) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Current:
Federal	$ 1,502,796	$ 672,064	$ 1,290,009
State and local	188,612	(168,846)	367,441
Total current	1,691,408	503,218	1,657,450
Deferred:
Federal		(96,804)	96,804
State and local		52,641	(52,641)
Total deferred		(44,163)	44,163
Income tax expense	$ 1,691,408	$ 459,055	$ 1,701,613

INCOME TAX EXPENSE - Income t_2

INCOME TAX EXPENSE - Income tax reconciliation (Details) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
INCOME TAX EXPENSE
Loss before income tax	$ (17,254,962)	$ (79,512,792)	$ (71,476,322)
PRC statutory income tax rate	25%	25%	25%
Income tax credit computed at PRC statutory income tax rate	$ (4,313,740)	$ (19,878,198)	$ (17,869,081)
Impact of PRC preferential income tax rate as qualified TASE	1,725,496	7,951,279	7,147,633
Difference in income tax rates of overseas entities	(1,012,031)	10,560,029	10,549,985
Research and development super-deduction	(693,340)	(1,724,740)	(569,016)
Research and development tax credits	(668,854)	(569,575)
Non-deductible expenses	7,241	3,695	1,054
Foreign derived intangible income deduction	(394,979)	(487,183)
Changes in valuation allowance	7,064,573	4,517,358	2,277,418
State tax	(22,363)	76,127	291,500
Others	(595)	10,263	(127,880)
Income tax expense	$ 1,691,408	$ 459,055	$ 1,701,613

INCOME TAX EXPENSE - Deferred t

INCOME TAX EXPENSE - Deferred tax assets and deferred tax liabilities (Details) - USD ($)	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Deferred tax assets:
Net operating loss carry forward	$ 15,413,070	$ 8,217,976
Tax credit carry forward	1,077,073	391,843
Capitalized research and development expenses		756,197
Capitalized inventory	72,402	94,954
Unrealized foreign exchange gain/losses	67,453	116,238
Accrued expenses		29,702
Amortization of right-of-use assets and interest of lease liabilities	676	546
Gross deferred tax assets	16,630,674	9,607,456
Less: valuation allowance	(16,589,070)	(9,524,497)	$ (5,007,139)	$ (2,729,721)
Total deferred tax assets, net	41,604	82,959
Deferred tax liabilities:
Depreciation and amortization of property, equipment and software	(41,604)	(82,959)
Deferred tax liabilities	$ (41,604)	$ (82,959)

INCOME TAX EXPENSE - Valuation

INCOME TAX EXPENSE - Valuation Allowance (Details) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Movement of the valuation allowance
Balance as of January 1	$ 9,524,497	$ 5,007,139	$ 2,729,721
Addition	7,064,573	4,517,358	2,277,418
Balance as of December 31	$ 16,589,070	$ 9,524,497	$ 5,007,139

NET LOSS PER SHARE - Schedule o

NET LOSS PER SHARE - Schedule of basic and diluted net loss per share (Details) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Numerator:
Net loss attributable to Adagene Inc.'s shareholders	$ (18,946,370)	$ (79,971,847)	$ (73,177,935)
Accretion of convertible redeemable preferred shares to redemption value			(28,553)
Net loss attributable to ordinary shareholders	$ (18,946,370)	$ (79,971,847)	$ (73,206,488)
Denominator:
Weightedaverage number of ordinary shares outstanding-basic	54,737,530	54,135,084	50,032,009
Weightedaverage number of ordinary shares outstanding-diluted	54,737,530	54,135,084	50,032,009
Net Loss per share-basic	$ (0.35)	$ (1.48)	$ (1.46)
Net Loss per share- diluted	$ (0.35)	$ (1.48)	$ (1.46)

NET LOSS PER SHARE - Anti-dilut

NET LOSS PER SHARE - Anti-dilutive Securities (Details) - shares	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Incremental shares on share options and share grant
NET LOSS PER SHARE
Antidilutive securities not included in the computation of diluted net loss per share	52,942	530,298	1,739,882

RELATED PARTY TRANSACTIONS (Det

RELATED PARTY TRANSACTIONS (Details) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Related Party Transaction [Line Items]
Amounts due from related parties	$ 222,027	$ 619,432
Other Receivable, after Allowance for Credit Loss, Current, Related Party, Type [Extensible Enumeration]	us-gaap:RelatedPartyMember	us-gaap:RelatedPartyMember
Amounts due to related parties	$ 16,714,326	$ 19,323,337
Other Liability, Current, Related Party, Type [Extensible Enumeration]	us-gaap:RelatedPartyMember	us-gaap:RelatedPartyMember
Receipt of CRO and CMO services
Related Party Transaction [Line Items]
Related party transactions	$ 2,660,504	$ 35,127,463	$ 13,079,018
WuXi Biologics (Cayman) Inc.
Related Party Transaction [Line Items]
Amounts due from related parties	$ 102,416	$ 115,491
Other Receivable, after Allowance for Credit Loss, Current, Related Party, Type [Extensible Enumeration]	us-gaap:SubsidiaryOfCommonParentMember	us-gaap:SubsidiaryOfCommonParentMember
Amounts due to related parties	$ 16,371,593	$ 17,840,876
Other Liability, Current, Related Party, Type [Extensible Enumeration]	us-gaap:SubsidiaryOfCommonParentMember	us-gaap:SubsidiaryOfCommonParentMember
WuXi Biologics (Cayman) Inc. | Receipt of CRO and CMO services
Related Party Transaction [Line Items]
Related party transactions	$ 1,868,815	$ 27,764,750	12,561,276
WuXi AppTec Group
Related Party Transaction [Line Items]
Amounts due from related parties	$ 118,594	$ 503,941
Other Receivable, after Allowance for Credit Loss, Current, Related Party, Type [Extensible Enumeration]	us-gaap:MajorityShareholderMember	us-gaap:MajorityShareholderMember
Amounts due to related parties	$ 341,716	$ 1,482,461
Other Liability, Current, Related Party, Type [Extensible Enumeration]	us-gaap:MajorityShareholderMember	us-gaap:MajorityShareholderMember
WuXi AppTec Group | Receipt of CRO and CMO services
Related Party Transaction [Line Items]
Related party transactions	$ 787,602	$ 7,362,713	$ 517,742
Certain senior management personnel
Related Party Transaction [Line Items]
Amounts due from related parties	1,017
Amounts due to related parties	1,017
Related party transactions	$ 4,087

LEASES - Information related to

LEASES - Information related to operating leases (Details) - USD ($)	Dec. 31, 2023	Dec. 31, 2022
Assets
Operating lease right-of-use assets	$ 365,103	$ 191,877
Liabilities
Current portion of operating lease liabilities	195,955	151,983
Operating lease liabilities	$ 173,660	$ 53,834
Weighted average remaining lease term (years)	2 years 1 month 6 days	1 year 3 months 18 days
Weighted average discount rate	4.40%	4.60%

LEASES - Information related _2

LEASES - Information related to operating lease activity (Details) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Operating lease rental expense
Amortization of right-of-use assets	$ 216,305	$ 283,276
Expense for short-term leases within 12 months	13,514	34,729
Interest of lease liabilities	12,100	20,259
Total operating lease rental expense	$ 241,919	$ 338,264

LEASES - Maturities of lease li

LEASES - Maturities of lease liabilities (Details) - USD ($)	Dec. 31, 2023	Dec. 31, 2022
LEASES
2023		$ 157,603
2024	$ 207,155	54,823
2025	123,546
2026	55,499
Total undiscounted lease payments	386,200	212,426
Less: imputed interest	(16,585)	(6,609)
Total lease liabilities	$ 369,615	$ 205,817

RESTRICTED NET ASSETS (Details)

RESTRICTED NET ASSETS (Details) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
RESTRICTED NET ASSETS
Minimum percentage of profit after tax to be transferred to statutory reserve	10%
Statutory reserve required percentage on registered capital	50%
Total restricted net assets	$ 1,860,667	$ 1,860,667
After tax income, annual appropriations, percentage	10%
Restrictions on net assets of PRC subsidiaries , threshold percentage	25%

Treasury Shares (Details)

Treasury Shares (Details) - USD ($)			12 Months Ended
	Jun. 29, 2022	Jul. 07, 2021	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Treasury Shares
Total consideration of share repurchased				$ 3,976,681	$ 2,361,576
Treasury shares			1	1
2021 Share Repurchase Program
Treasury Shares
Share repurchase program authorized amount		$ 20,000,000
Term of share repurchase program (in months)		12 months
2022 Share Repurchase Program
Treasury Shares
Share repurchase program authorized amount	$ 10,000,000
Term of share repurchase program (in months)	12 months
American depositary shares
Treasury Shares
Repurchased shares retired (in shares)				1,285,604	160,880
Treasury shares			1	1
American depositary shares | 2021 Share Repurchase Program
Treasury Shares
Shares repurchased (in shares)				1,170,446	236,139
Total consideration of share repurchased				$ 3,904,399	$ 2,361,576
American depositary shares | 2022 Share Repurchase Program
Treasury Shares
Shares repurchased (in shares)				39,900
Total consideration of share repurchased				$ 72,282
Ordinary shares
Treasury Shares
Repurchased shares retired (in shares)			0	1,607,005	201,100
Treasury shares			1	1
Ordinary shares | 2021 Share Repurchase Program
Treasury Shares
Shares repurchased (in shares)				1,463,057	295,174
Ordinary shares | 2022 Share Repurchase Program
Treasury Shares
Shares repurchased (in shares)			0	49,875