Galecto (GLTO) 10-K 17 Feb 22 2021 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Feb. 15, 2022	Jun. 30, 2021
Cover [Abstract]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2021
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	FY
Current Fiscal Year End Date	--12-31
Document Annual Report	true
Document Transition Report	false
Entity File Number	001-39655
Entity Registrant Name	GALECTO, INC.
Entity Central Index Key	0001800315
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	37-1957007
Entity Address, Address Line One	75 State Street
Entity Address, Address Line Two	Suite 100
Entity Address, City or Town	Boston
Entity Address, State or Province	MA
Entity Address, Postal Zip Code	02109
City Area Code	+45
Local Phone Number	70 70 52 10
Title of 12(b) Security	Common Stock, par value $0.00001 per share
Trading Symbol	GLTO
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		25,261,832
Entity Public Float			$ 88.9
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
ICFR Auditor Attestation Flag	false
Auditor Name	EY Godkendt Revisionspartnerselskab
Auditor Location	Copenhagen, Denmark
Auditor Firm ID	1757
Documents Incorporated by Reference	DOCUMENTS INCORPORATED BY REFERENCE The registrant intends to file a definitive proxy statement pursuant to Regulation 14A relating to the 2021 Annual Meeting of Stockholders within 120 days of the end of the registrant’s fiscal year ended December 31, 2020. Portions of such definitive proxy statement are incorporated by reference into Part II and Part III of this Annual Report on Form 10-K to the extent stated herein.

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Current assets
Cash and cash equivalents	$ 62,563	$ 163,582
Marketable securities	37,628
Prepaid expenses and other current assets	9,911	5,713
Total current assets	110,102	169,295
Marketable securities, non-current	9,048
Operating lease right-of-use asset	834	885
Equipment, net	203
Restricted cash		254
Other assets, noncurrent	2,028	1,162
Total assets	122,215	171,596
Current liabilities
Accounts payable	1,531	2,851
Accrued expenses and other current liabilities	3,013	2,715
Total current liabilities	4,544	5,566
Operating lease liabilities, noncurrent	448	541
Total liabilities	4,992	6,107
Commitments and contingencies (Note 9)
Stockholders’ equity
Preferred stock, par value of $0.00001 per share; 10,000,000 shares authorized at December 31, 2021 and 2020; no shares issued or outstanding as of December 31, 2021 and 2020
Additional paid-in capital	273,655	269,175
Accumulated deficit	(156,112)	(104,360)
Accumulated other comprehensive income (loss)	(320)	674
Total stockholders’ equity	117,223	165,489
Total liabilities and stockholders’ equity	$ 122,215	$ 171,596

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - $ / shares	Dec. 31, 2021	Dec. 31, 2020
Statement Of Financial Position [Abstract]
Preferred stock, par value	$ 0.00001	$ 0.00001
Preferred stock, authorized	10,000,000	10,000,000
Preferred stock, issued	0	0
Preferred stock, outstanding	0	0
Common stock, par value	$ 0.00001	$ 0.00001
Common stock, authorized	300,000,000	300,000,000
Common stock, issued	25,261,832	25,261,832
Common stock, outstanding	25,261,832	25,261,832

Consolidated Statements of Oper

Consolidated Statements of Operations and Comprehensive Loss - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Operating expenses
Research and development	$ 38,488	$ 24,627
General and administrative	13,739	9,010
Total operating expenses	52,227	33,637
Loss from operations	(52,227)	(33,637)
Other income (expense), net
Interest income, net	156
Foreign exchange transaction gain (loss), net	319	(1,200)
Total other income (expense), net	475	(1,200)
Net loss	$ (51,752)	$ (34,837)
Net loss per common share, basic and diluted	$ (2.05)	$ (7.62)
Weighted-average number of shares used in computing net loss per common share, basic and diluted	25,261,832	4,572,702
Other comprehensive loss, net of tax
Currency translation gain (loss)	$ (917)	$ 3,125
Unrealized loss on marketable securities, net	(77)
Other comprehensive gain (loss), net of tax	(994)	3,125
Total comprehensive loss	$ (52,746)	$ (31,712)

Consolidated Statements of Conv

Consolidated Statements of Convertible Preferred Stock and Changes in Stockholders' Equity - USD ($) $ in Thousands	Total	Series B Convertible Preferred Stock	Series C Convertible Preferred Stock	Series D Convertible Preferred Stock	Common Stock	Additional Paid-In Capital	Accumulated Deficit	Accumulated Other Comprehensive Income (Loss)
Beginning balance at Dec. 31, 2019	$ (71,148)					$ 826	$ (69,523)	$ (2,451)
Beginning balance (in shares) at Dec. 31, 2019		684,068	4,125,056
Beginning balance at Dec. 31, 2019		$ 13,414	$ 106,205
Beginning balance (in shares) at Dec. 31, 2019					259,966
Issuance of Series D preferred stock, net of issuance costs of $2,840				$ 61,359
Issuance of preferred stock (in shares)				2,368,118
Issuance of common stock in connection with initial public offering, net of issuance costs of $2,114	86,360					86,360
Issuance of common stock in connection with initial public offering, net of issuance costs (in shares)					6,342,207
Conversion of convertible preferred stock into common stock	180,978	$ (13,414)	$ (106,205)	$ (61,359)		180,978
Conversion of convertible preferred stock into common stock (in shares)		(684,068)	(4,125,056)	(2,368,118)	18,658,643
Stock-based compensation expense	1,009					1,009
Exercise of stock options	$ 2					2
Exercise of stock options (in shares)	1,016				1,016
Currency translation gain (loss)	$ 3,125							3,125
Net loss	(34,837)						(34,837)
Ending balance at Dec. 31, 2020	165,489					269,175	(104,360)	674
Ending balance (in shares) at Dec. 31, 2020					25,261,832
Stock-based compensation expense	4,480					4,480
Currency translation gain (loss)	(917)							(917)
Unrealized loss on marketable securities, net	(77)							(77)
Net loss	(51,752)						(51,752)
Ending balance at Dec. 31, 2021	$ 117,223					$ 273,655	$ (156,112)	$ (320)
Ending balance (in shares) at Dec. 31, 2021					25,261,832

Consolidated Statements of Co_2

Consolidated Statements of Convertible Preferred Stock and Changes in Stockholders' Equity (Parenthetical) $ in Thousands	12 Months Ended
	Dec. 31, 2020USD ($)
Series D Convertible Preferred Stock
Preferred stock issuance costs, net	$ 2,840
Initial Public Offering
Common stock issuance costs, net	$ 2,114

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Cash flows from operating activities
Net loss	$ (51,752,000)	$ (34,837,000)
Adjustment to reconcile net loss to net cash used in operating activities:
Depreciation	20,000
Stock-based compensation	4,480,000	982,000
Amortization of premiums and discounts on marketable securities	1,072,000
Amortization of right of use lease asset	421,000	188,000
Accretion of lease liability	75,000	55,000
Changes in operating assets and liabilities:
Prepaid expenses and other current assets	(4,199,000)	(596,000)
Other assets, noncurrent	(866,000)	(1,162,000)
Accounts payable	(1,320,000)	(477,000)
Accrued expenses and other current liabilities	274,000	(2,143,000)
Operating lease liabilities	(513,000)	(213,000)
Net cash used in operating activities	(52,308,000)	(38,203,000)
Cash flows from investing activities
Purchases of marketable securities	(84,209,000)
Proceeds from sale of marketable securities	36,384,000
Purchases of property and equipment	(223,000)
Net cash used in investing activities	(48,048,000)
Cash flows from financing activities
Proceeds from the issuance of common stock in connection with initial public offering		88,473,000
Initial public offering issuance costs		(2,114,000)
Proceeds from exercise of stock options		2,000
Net cash provided by financing activities		187,389,000
Net increase (decrease) in cash and cash equivalents	(100,356,000)	149,186,000
Effect of exchange rate changes on cash and cash equivalents	(917,000)	3,125,000
Cash, cash equivalents and restricted cash, beginning of year	163,836,000	11,525,000
Cash, cash equivalents and restricted cash, end of year	62,563,000	163,836,000
Components of cash, cash equivalents, and restricted cash
Cash and cash equivalents	62,563,000	163,582,000
Restricted cash		254,000
Cash, cash equivalents and restricted cash, end of year	62,563,000	163,836,000
Supplemental disclosures of noncash activities:
Operating lease liability arising from obtaining right-of-use assets	$ 411,000	713,000
Series C Convertible Preferred Stock
Cash flows from financing activities
Proceeds from issuance of preferred stock		39,669,000
Series D Convertible Preferred Stock
Cash flows from financing activities
Proceeds from issuance of preferred stock		64,199,000
Series D preferred stock issuance costs		$ (2,840,000)

Description of Business, Organi

Description of Business, Organization and Liquidity	12 Months Ended
	Dec. 31, 2021
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Description of Business, Organization and Liquidity	1. DESCRIPTION OF BUSINESS, ORGANIZATION AND LIQUIDITY Business Galecto, Inc., together with its consolidated subsidiaries, or the Company or Galecto, is a clinical-stage biotechnology company developing novel therapeutics that are designed to target the biological processes that lie at the heart of fibrotic diseases and cancer. The Company’s initial focus is on the development of small molecule inhibitors of galectin-3 and lysyl oxidase-like 2, or LOXL2, which play key roles in regulating fibrosis and cancer. As of December 31, 2021, the Company’s wholly owned subsidiaries were PharmAkea, Inc. or PharmAkea, Galecto Securities Corporation and Galecto Biotech AB, a Swedish company. Galecto Biotech ApS, a Danish operating company, is a wholly-owned subsidiary of Galecto Biotech AB. Risks and uncertainties The Company is subject to risks common to companies in the biotechnology industry including, but not limited to, new technological innovations, protection of proprietary technology, dependence on key personnel, compliance with government regulations and the need to obtain additional financing. Product candidates currently under development will require significant additional research and development efforts, including extensive preclinical and clinical testing and regulatory approval, prior to commercialization. These efforts require significant amounts of additional capital, adequate personnel infrastructure and extensive compliance reporting capabilities. The Company’s product candidates are in development. There can be no assurance that the Company’s research and development will be successfully completed, that adequate protection for the Company’s intellectual property will be obtained, that any products developed will obtain necessary government regulatory approval or that any approved products will be commercially viable. Even if the Company’s product development efforts are successful, it is uncertain when, if ever, the Company will generate significant revenue from product sales. The Company operates in an environment of rapid change in technology and substantial competition from pharmaceutical and biotechnology companies. In addition, the Company is dependent upon the services of its employees and consultants. Liquidity and management plans Since inception, the Company has devoted substantially all its efforts to business planning, research and development, recruiting management and technical staff and raising capital, and has financed its operations primarily through the issuance of redeemable convertible preferred shares, debt financings and, most recently, the Company’s initial public offering, or IPO. As of December 31, 2021, the Company had an accumulated deficit of $156.1 million, from recurring losses since inception in 2011. The Company has incurred recurring losses and has not generated revenue as no products have obtained the necessary regulatory approval in order to market products. The Company expects to continue to incur losses as a result of costs and expenses related to the Company’s clinical development and corporate general and administrative activities. The Company had negative cash flows from operating activities during the years ended December 31, 2021 and 2020 of $52.3 million and $38.2 million, respectively, and current projections indicate that the Company will have continued negative cash flows for the foreseeable future as it continues to develop its product candidates. Net losses incurred for the years ended December 31, 2021 and 2020 amounted to $51.8 million and $34.8 million, respectively. At December 31, 2021, the Company’s cash, cash equivalents and marketable securities amounted to $109.2 million, current assets amounted to $110.1 million and current liabilities amounted to $4.5 million. At December 31, 2020, the Company’s cash and cash equivalents amounted to $163.6 million, current assets amounted to $169.3 million and current liabilities amounted to $5.6 million. In the future, the Company will consider the following ways to fund its operations including: (1) raising additional capital through equity and/ or debt financings; (2) new commercial relationships to help fund future clinical trial costs (i.e. licensing and partnerships); (3) reducing spending on one or more research and development programs by discontinuing development; and/or (4) restructuring operations to change its overhead structure. The Company’s future liquidity needs, and ability to address those needs, will largely be determined by the success of its product candidates and key development and regulatory events and its decisions in the future. Coronavirus pandemic The outbreak of the novel coronavirus, or COVID-19, and ensuing pandemic, has spread worldwide, caused many governments to implement measures to slow the spread of the outbreak through quarantines, travel restrictions, heightened border scrutiny and other measures. The outbreak and government measures taken in response have also had a significant impact, both directly and indirectly, on businesses and commerce, as worker shortages have occurred; supply chains have been disrupted; facilities and production have been suspended; and demand for certain goods and services, such as medical services and supplies, has spiked, while demand for other goods and services, such as travel, has fallen. The future progression of the outbreak and its effects on the Company’s business and operations are uncertain. In response to the impact of COVID-19, the Company has implemented certain measures intended to help the Company manage its impact and position the Company to resume operations quickly and efficiently once these restrictions are lifted, such as executing a work-from-home strategy for administrative functions and operations. The Company continues to monitor the impact of COVID-19 and assess its strategy accordingly. Despite the Company’s implementation of such measures, the actual and perceived impact of the COVID-19 pandemic is changing daily, and its ultimate effect on the Company cannot be predicted. As a result, there can be no assurance that the Company will not experience additional negative impacts associated with COVID-19, which could be significant. The COVID-19 pandemic may negatively impact the Company’s business, financial condition and results of operations by decreasing or delaying the enrollment of patients in the Company’s clinical trials or otherwise causing interruptions or delays in the Company’s programs and services. On March 27, 2020, the United States enacted the Coronavirus Aid, Relief and Economic Security Act, or CARES Act. The CARES Act is an emergency economic stimulus package that includes spending and tax breaks to strengthen the United States economy and fund a nationwide effort to curtail the effect of COVID-19. The CARES Act provides sweeping tax changes in response to the COVID-19 pandemic, some of the more significant provisions include removing certain limitations on the utilization of net operating losses, increasing the loss carryback period for certain losses to five years, increasing the ability to deduct interest expense, and deferring social security payments, as well as amending certain provisions of the previously enacted Tax Cuts and Jobs Act. The Company does not believe the CARES Act will have a material impact on its financial position and results of operations.

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2021
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	2. SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Basis of presentation The accompanying consolidated financial statements have been prepared in conformity with United States, or U.S., generally accepted accounting principles, or GAAP. Any reference in these notes to applicable guidance is meant to refer to U.S. GAAP, as found in the Accounting Standards Codification, or ASC, and Accounting Standards Update, or ASU, of the Financial Accounting Standards Board, or FASB. Principles of consolidation The Company’s consolidated financial statements for 2021 and 2020 include Galecto, Inc. and its subsidiaries. All intercompany balances and transactions have been eliminated in 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, disclosure of contingent assets and liabilities at the date of the consolidated financial statements, and the reported amounts of expenses during the reporting periods. The Company bases its estimates on historical experience and various other assumptions that management believes to be reasonable under the circumstances. Significant items subject to such estimates and assumptions include contract research accruals, accounting for stock-based compensation and valuation of the Company’s deferred tax assets. Changes in estimates are recorded in the period in which they become known. The Company’s actual results could differ from those estimates. Currency and currency translation The consolidated financial statements are presented in U.S. dollars, the Company’s reporting currency. Galecto, Inc., Galecto Securities Corporation and PharmAkea’s functional currency is the U.S. dollar. The functional currency of the Company’s subsidiary Galecto Biotech AB, and its subsidiary Galecto Biotech ApS, is the Euro. Adjustments that arise from exchange rate changes on transactions of each group entity denominated in a currency other than the functional currency are included in other income and expense in the consolidated statements of operations. Assets and liabilities of Galecto Biotech AB and Galecto Biotech ApS recorded in their Euro functional currency are translated into the U.S. dollar reporting currency of the Company at the exchange rate on the balance sheet date. Revenue and expenses of Galecto Biotech AB and Galecto Biotech ApS recorded in their Euro functional currency are translated into the U.S. dollar reporting currency of the Company at the average exchange rate prevailing during the year. Resulting translation adjustments are recorded to accumulated other comprehensive income (loss), or OCI. Cash and cash equivalents The Company considers all highly liquid investments with original maturities at the date of purchase of three months or less to be cash equivalents. Cash and cash equivalents are stated at fair value and may include money market funds, U.S. Treasury and U.S. government-sponsored agency securities, corporate debt, commercial paper and certificates of deposit. The Company had money market funds of $49.6 and $142.9 million as of December 31, 2021 and 2020, respectively, which are included in cash and cash equivalents and reported at fair value (Note 4). Restricted cash The Company is required to maintain cash collateral on deposit in a segregated money market bank account, as a condition of its security deposit with one of its banks for the use of corporate credit cards. As of December 31, 2020, the Company presented restricted cash in the accompanying consolidated balance sheets of $0.3 million. There was no restricted cash as of December 31, 2021. Concentrations of credit risk and off-balance sheet risk Financial instruments that subject the Company to significant concentrations of credit risk consist primarily of cash, cash equivalents, restricted cash and marketable securities. Substantially all of the Company’s cash is held at financial institutions that management believes to be of high-credit quality. The Company maintains its cash in bank deposit and checking accounts that at times exceed insured limits. The Company has not experienced any losses in such accounts and believes it is not exposed to any significant credit risk. Investments in Marketable Securities The Company invests excess cash balances in short-term and long-term marketable debt securities. The Company classifies investments in marketable debt securities as either held-to-maturity or available-for-sale based on the facts and circumstances present at the time of purchase and re-evaluates classification at each balance sheet date. All investments in marketable debt securities at each balance sheet date presented, are generally considered as available-for-sale. Marketable debt securities with maturities of twelve months or less are classified as short-term investments and marketable debt securities with maturities greater than twelve months are classified based on their availability for use in current operations. The Company reports available-for-sale debt securities at fair value at each balance sheet date and includes any unrealized holding gains and losses (the adjustment to fair value), net of applicable taxes, in accumulated other comprehensive income (loss), a component of stockholders’ equity. The cost of debt securities is adjusted for the amortization of premium and accretion of discounts to maturity. Such amortization and accretion is included in interest income. Fair value of financial instruments Fair value is defined as the price the Company would receive to sell an investment in a timely transaction or pay to transfer a liability in a timely transaction with an independent buyer in the principal market, or in the absence of a principal market, the most advantageous market for the investment or liability. A framework is used for measuring fair value utilizing a three-tier hierarchy that prioritizes the inputs to valuation techniques used to measure fair value. The hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (Level 1) and the lowest priority to unobservable inputs (Level 3). The three levels of the fair value hierarchy are as follows: Level 1 —Unadjusted quoted prices in active markets that are accessible at the measurement date for identical, unrestricted assets or liabilities; Level 2 —Quoted prices in markets that are not considered to be active or financial instrument valuations for which all significant inputs are observable, either directly or indirectly; and Level 3 —Prices or valuations that require inputs that are both significant to the fair value measurement and unobservable. Financial instruments are categorized in their entirety based on the lowest level of input that is significant to the fair value measurement. The assessment of the significance of a particular input to the fair value measurement requires judgment and considers factors specific to the investment. To the extent that the valuation is based on models or inputs that are less observable or unobservable in the market, the determination of fair value requires more judgment. Accordingly, the degree of judgment exercised by us in determining fair value is greatest for instruments categorized in Level 3. The Company monitors the availability of inputs that are significant to the measurement of fair value to assess the appropriate categorization of financial instruments within the fair value hierarchy. Changes in economic conditions or model-based valuation techniques may require the transfer of financial instruments from one fair value level to another. In such instances, our policy is to recognize significant transfers between levels at the end of the reporting period. The significance of transfers between levels is evaluated based upon the nature of the financial instrument and size of the transfer relative to total net assets available for benefits. Leases The Company determines whether an arrangement is or contains a lease at the time it enters into a contract. For all leases, the Company determines the classification as either operating leases or finance leases. Operating leases are included in operating lease right-of-use, or ROU, assets and accrued expenses and other current liabilities and operating lease liabilities, noncurrent in the Company’s consolidated balance sheets. The Company has not entered into any financing leases. Lease recognition occurs at the commencement date and lease liability amounts are based on the present value of lease payments over the lease term. The lease terms may include options to extend or terminate the lease when it is reasonably certain that the Company will exercise that option. If a lease does not provide information to determine an implicit interest rate, the Company uses the Company’s incremental borrowing rate in determining the present value of lease payments. ROU assets represent the right to use an underlying asset for the lease term, and lease liabilities represent the obligation to make lease payments under the lease. ROU assets also include any lease payments made prior to the commencement date and exclude lease incentives received. Operating lease expense is recognized on a straight-line basis over the lease term. The depreciable life of assets and leasehold improvements are limited by the expected lease term, unless there is a transfer of title or purchase option reasonably certain of exercise. Lease agreements with both lease and non-lease components, are generally accounted for together as a single lease component. Refer to Note 6 for further details. Property and Equipment, Net Property and equipment are recorded at cost. Costs associated with maintenance and repairs are expensed as incurred. Depreciation is provided using the straight-line method over the estimated useful lives: Asset Category Useful Life Equipment 5-7 years Furniture and fixtures 5 years Leasehold improvements Lesser of 10 years or the remaining term of the respective lease Impairment of Long-Lived Assets Long-lived assets to be held and used are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of the asset may not be recoverable. When such events occur, the Company compares the carrying amounts of the assets to their undiscounted expected future cash flows. If the undiscounted cash flows are insufficient to recover the carrying value, an impairment loss is recorded for the difference between the carrying value and fair value of the asset. Through December 31, 2021 , no such impairment has occurred. Research and development expenses Research and development costs are expensed as incurred. The Company’s research and development expenses consist primarily of costs incurred for the development of its product candidates and include expenses incurred under agreements with contract manufacturing organizations, or CMOs, contract research organizations, or CROs, investigative sites and consultants to conduct clinical trials and preclinical and non-clinical studies, costs to acquire, develop and manufacture supplies for clinical trials and other studies, salaries and related costs, including stock-based compensation, depreciation The Company has met the requirements to receive a tax credit in Denmark for losses resulting from research and development costs of up to $3.8 million and $4.1 million for the years ended December 31, 2021 and 2020, respectively. The tax credit is reported as a reduction to research and development expense in the consolidated statements of operations. For the years ended December 31, 2021 and 2020, research and development expenses include refundable tax credits of $0.9 million and $0.8 million, respectively. Accrued research and development costs Substantial portions of the Company’s preclinical and clinical trials are performed by third-party laboratories, medical centers, CROs and other vendors, or collectively, CROs. These CROs generally bill monthly for services performed, or bill based upon milestone achievement. For preclinical studies, the Company accrues expenses based upon estimated percentage of work completed and the contract milestones remaining. For clinical studies, expenses are accrued based upon the number of patients enrolled and the duration of the study. The Company monitors patient enrollment, the progress of clinical studies and related activities to the extent possible through internal reviews of data reported to the Company by the CROs, and correspondence with the CROs and clinical site visits. The Company’s estimates depend on the timeliness and accuracy of the data provided by the CROs regarding the status of each program and total program spending. The Company periodically evaluates the estimates to determine if adjustments are necessary or appropriate based on information it receives. Convertible preferred stock The Company classifies convertible preferred stock outside of stockholders’ deficit on its consolidated balance sheet as the requirements of triggering a deemed liquidation event are not within the Company’s control. The Company records the issuance of convertible preferred stock at the issuance price less related issuance costs and less any discount arising on allocation of proceeds to one or more derivative features. In September 2020, the Company sold and issued 2,368,118 shares of Series D preferred stock for gross proceeds of $64.2 million, or $61.4 million net of $2.8 million in issuance costs. Immediately prior to consummation of, and in connection with, the Company’s IPO, all outstanding shares of the Company’s convertible preferred stock were converted into18,658,643 shares of common stock. Stock-based compensation The Company accounts for stock options granted in accordance with ASC 718, Compensation-Stock Compensation All share-based awards granted are measured based on the fair value on the date of the grant and compensation expense is recognized with respect to those awards over the requisite service period, which is generally the vesting period of the respective award. The Company reverses any previously recognized compensation cost associated with forfeited awards in the period the forfeiture occurs. Equity-based compensation expense is classified in the Company’s consolidated statement of operations and comprehensive loss in the same manner in which the award recipients’ payroll costs are classified or in which the award recipients’ service payments are classified. The fair value of each stock option grant is estimated on the date of grant using the Black-Scholes model. The following summarizes the inputs used: Expected volatility —The Company estimates its expected stock volatility based on the historical volatility of a publicly traded set of peer companies because we lack company-specific historical and implied volatility information due in part to the limited time in which we have operated as a publicly traded company. We expect to continue to do so until such time as we have adequate historical data regarding the volatility of our traded stock price. Expected term —The expected term of the Company’s stock options has been determined based on the expected time to liquidity. The Company uses the simplified method prescribed by the SEC’s Staff Accounting Bulletin No. 107, Share-Based Payment , to calculate the expected term of options granted because we lack company-specific historical and implied expected term information due in part to the limited time in which we have operated as a publicly traded company . Risk-free interest rate —The risk-free interest rate is based on the implied yield on a U.S. Treasury security at a constant maturity with a remaining term equal to the expected term of the option granted. Dividends —Expected dividend yield is zero because the Company does not pay cash dividends on common shares and does not expect to pay any cash dividends in the foreseeable future. Income taxes Deferred income tax assets and liabilities arise from temporary differences associated with differences between the financial statements and tax basis of assets and liabilities, as measured by the enacted tax rates, which are expected to be in effect when these differences reverse. Valuation allowances are established when necessary to reduce deferred tax assets to the amount expected to be realized. The Company has generated net losses since inception and accordingly has not recorded a provision for income taxes. The Company follows the provisions of ASC 740-10, Uncertainty in Income Taxes, The Company has identified the United States, Denmark, United Kingdom and Sweden as its major tax jurisdictions. Refer to Note 12 for further details. Net loss per share Basic net loss per share is computed by dividing the net loss by the weighted-average number of shares of common stock outstanding for the period. Diluted net loss per share is computed by dividing the net loss by the weighted-average number of shares of common stock and dilutive common stock equivalents outstanding for the period, determined using the treasury-stock method and the as if-converted method, for convertible securities, if inclusion of these instruments is dilutive. For the years ended December 31, 2021 and 2020, both methods are equivalent. Basic and diluted net loss per share is described further in Note 13. Segments Operating segments are defined as components of an entity for which separate financial information is available and that is regularly reviewed by the chief operating decision maker, or CODM, in deciding how to allocate resources to an individual segment and in assessing performance. The Company’s CODM is its chief executive officer. The Company has determined it operates in one segment. Other comprehensive gain (loss) Other comprehensive gain (loss), or OCI, is defined as the change in equity of a business enterprise during a period from transactions and other events and circumstances from non-owner sources. The Company’s OCI includes currency translation and unrealized gain or (loss) on marketable securities. Emerging growth company status The Company is an emerging growth company, as defined in the Jumpstart Our Business Startups Act of 2012, or JOBS Act. Under the JOBS Act, emerging growth companies can delay adopting new or revised accounting standards issued subsequent to the enactment of the JOBS Act, until such time as those standards apply to private companies. The Company may elect to use this extended transition period for complying with new or revised accounting standards that have different effective dates for public and private companies until the earlier of the date that it (i) is no longer an emerging growth company or (ii) affirmatively and irrevocably opts out of the extended transition period provided in the JOBS Act. As a result, and as a smaller reporting company, these financial statements may not be comparable to companies that comply with the new or revised accounting pronouncements as of public company effective dates. Recently adopted accounting standards In December 2019, the FASB issued ASU No. 2019-12, Simplifying the Accounting for Income Taxes Recently issued accounting standards In June 2016, the FASB issued ASU No. 2016-13, Financial Instruments-Credit Losses: Measurement of Credit Losses on Financial Instruments Codification Improvements to Topic 326, Financial Instruments-Credit Losses, Topic 815, Derivatives and Hedging and Topic 825, Financial Instruments

Investments in Marketable Secur

Investments in Marketable Securities	12 Months Ended
	Dec. 31, 2021
Investments Debt And Equity Securities [Abstract]
Investments in Marketable Securities	3. INVESTMENTS IN MARKETABLE SECURITIES Cash in excess of the Company’s immediate requirements is invested in accordance with the Company’s investment policy that primarily seeks to maintain adequate liquidity and preserve capital. A summary of the Company’s available-for-sale investments as of December 31, 2021 consisted of the following (in thousands): At December 31, 2021 Amortized Gross Unrealized Gross Unrealized Fair Marketable securities: Cost Gains Losses Value Corporate bonds $ 37,671 $ — $ (43 ) $ 37,628 Total $ 37,671 $ — $ (43 ) $ 37,628 Marketable securities, non-current: Corporate bonds $ 9,082 $ — $ (34 ) $ 9,048 Total $ 9,082 $ — $ (34 ) $ 9,048 The Company had no investments in marketable securities as of December 31, 2020.

Fair Value Measurements

Fair Value Measurements	12 Months Ended
	Dec. 31, 2021
Fair Value Disclosures [Abstract]
Fair Value Measurements	4. FAIR VALUE MEASUREMENTS Fair value is defined as the exchange price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. Valuation techniques used to measure fair value are performed in a manner to maximize the use of observable inputs and minimize the use of unobservable inputs. The Company classified its money market funds within Level 1 because their fair values are based on their quoted market prices. The Company classified its debt securities within Level 2 because their fair values are determined using alternative pricing sources or models that utilized market observable inputs. A summary of the assets that are measured at fair value as of December 31, 2021 and 2020 is as follows (in thousands): Fair Value Measurement at December 31, 2021 Assets: Carrying Value Quoted Prices in Active Markets for Identical Assets (Level 1) Significant other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Money market funds (1) $ 49,626 $ 49,626 $ — $ — Debt securities 46,676 — 46,676 — Total $ 96,302 $ 49,626 $ 46,676 $ — Fair Value Measurement at December 31, 2020 Assets: Carrying Value Quoted Prices in Active Markets for Identical Assets (Level 1) Significant other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Money market funds (1) $ 142,904 $ 142,904 $ — $ — Total $ 142,904 $ 142,904 $ — $ — (1) Money market funds with maturities of 90 days or less at the date of purchase are included within cash and cash equivalents in the accompanying consolidated balance sheets and are recognized at fair value.

Prepaid Expenses and Other Curr

Prepaid Expenses and Other Current Assets	12 Months Ended
	Dec. 31, 2021
Prepaid Expense And Other Assets Current [Abstract]
Prepaid Expenses and Other Current Assets	5. PREPAID EXPENSES AND OTHER CURRENT ASSETS Prepaid expenses and other current assets consist of the following (in thousands): December 31, 2021 2020 Contract research and development costs $ 5,569 $ 1,620 Prepaid insurance costs 1,728 1,642 Research and development tax credit receivable 1,682 1,808 Value-added tax refund receivable 598 401 Other 334 242 Total prepaid expenses and other current assets $ 9,911 $ 5,713

Leases

Leases	12 Months Ended
	Dec. 31, 2021
Leases [Abstract]
Leases	6. LEASES The Company has the following operating leases: Location Primary Use Lease Expiration Date Renewal Option Copenhagen, Denmark Corporate headquarters January 2025 None London, United Kingdom Office space August 2022 None Gothenburg, Sweden Office space May 2023 None Stevenage, United Kingdom Laboratory space January 2024 None The Company has no finance leases and has elected to apply the short-term lease exception to all leases of one year or less. Rent expense for years ended December 31, 2021 and 2020 was $0.5 million and $0.2 million, respectively. Quantitative information regarding the Company’s leases for the years ended December 31, 2021 and 2020 is as follows (in thousands): Year Ended December 31, Lease Cost: 2021 2020 Operating lease cost $ 496 $ 213 Other Information: Operating cash flows paid for amounts included in the measurement of lease liabilities $ 513 $ 213 Operating lease liabilities arising from obtaining right-of-use assets $ 411 $ 713 As of December 31, 2021 and 2020, the weighted average remaining lease term for operating leases was 2.4 years and 2.8 years, respectively. As of December 31, 2021 and 2020, the weighted average discount rate for operating leases was 8% Operating lease liabilities are as follows at December 31, 2021 (in thousands): Operating Leases 2022 $ 442 2023 273 2024 204 2025 17 2026 — Total lease payments 936 Less: imputed interest (90 ) Total lease liabilities $ 846

Equipment, Net

Equipment, Net	12 Months Ended
	Dec. 31, 2021
Property Plant And Equipment [Abstract]
Equipment, Net	7. EQUIPMENT, NET E quipment as of December 31, 2021 consisted of the following (in thousands): December 31, 2021 Equipment $ 223 Less: accumulated depreciation (20 ) Equipment, net $ 203 Depreciation expense for the year ended December 31, 2021 was $20,000. The Company had no equipment as of December 31, 2020.

Accrued Expenses and Other Curr

Accrued Expenses and Other Current Liabilities	12 Months Ended
	Dec. 31, 2021
Payables And Accruals [Abstract]
Accrued Expenses and Other Current Liabilities	8. ACCRUED EXPENSES AND OTHER CURRENT LIABILITIES Accrued expenses and other current liabilities consist of the following (in thousands): December 31, 2021 2020 Contract research and development costs $ 1,575 $ 967 Employee compensation costs 601 1,031 Lease liabilities, current 399 374 Other current liabilities 438 343 Total accrued expenses and other current liabilities $ 3,013 $ 2,715

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2021
Commitments And Contingencies Disclosure [Abstract]
Commitments and Contingencies	9. COMMITMENTS AND CONTINGENCIES Lease commitments The Company’s commitments related to lease agreements are disclosed in Note 6. Legal proceedings From time to time, the Company may be party to litigation arising in the ordinary course of its business. The Company was not subject to any material legal proceedings during the years ended December 31, 2021 and 2020, and, to its knowledge, no material legal proceedings are currently pending or threatened. Indemnification agreements The Company, as permitted under Delaware law and in accordance with its certification of incorporation and bylaws and pursuant to indemnification agreements with certain of its officers and directors, indemnifies its officers and directors for certain events or occurrences, subject to certain limits, which the officer or director is or was serving at the Company’s request in such capacity. The Company enters into certain types of contracts that contingently requires the Company to indemnify various parties against claims from third parties. These contracts primarily relate to (i) the Company’s bylaws, under which the Company must indemnify directors and executive officers, and may indemnify other officers and employees, for liabilities arising out of their relationship, (ii) contracts under which the Company must indemnify directors and certain officers and consultants for liabilities arising out of their relationship, and (iii) procurement, service or license agreements under which the Company may be required to indemnify vendors, service providers or licensees for certain claims, including claims that may be brought against them arising from the Company’s acts or omissions with respect to the Company’s products, technology, intellectual property or services. From time to time, the Company may receive indemnification claims under these contracts in the normal course of business. In the event that one or more of these matters were to result in a claim against the Company, an adverse outcome, including a judgment or settlement, may cause a material adverse effect on the Company’s future business, operating results or financial condition. It is not possible to estimate the maximum amount potentially payable under these contracts since the Company has no history of prior indemnification claims and the unique facts and circumstances involved in each particular claim will be determinative.

Stockholders' Equity

Stockholders' Equity	12 Months Ended
	Dec. 31, 2021
Stockholders Equity Note [Abstract]
Stockholders' Equity	10. STOCKHOLDERS’ EQUITY Common and preferred stock In October 2020, the Company completed its IPO selling an aggregate of 6,342,207 shares of common stock at $15.00 per share, which included 675,540 shares that represented the partial exercise in November 2020 of an option to purchase additional shares granted to the underwriters in connection with the IPO. The offering resulted in $86.3 million of net proceeds to the Company, after deducting underwriting discounts and commissions and other offering expenses payable by the Company. Upon the closing of the Company’s IPO, the Company filed an amended and restated certificate of incorporation, which authorized the Company to issue 300,000,000 shares of common stock and 10,000,000 shares of preferred stock, which shares of preferred stock are currently undesignated. The Company had 25,261,832 common shares outstanding at December 31, 202 1 . No dividends have been declared or paid by the Company through December 31, 2021 .

Stock-Based Compensation

Stock-Based Compensation	12 Months Ended
	Dec. 31, 2021
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Stock-Based Compensation	11. STOCK-BASED COMPENSATION Employee equity plan In March 2020, the Company replaced the 2013 Option Program, or (“2013 Plan”), with its 2020 Stock Option and Grant Plan, or (“2020 Plan”). The 2020 Plan initially allowed the Company to award up to 1,740,325 options and the 304,142 outstanding options granted under the 2013 Plan were transferred to the 2020 Plan. Each vested option will entitle the option holder to purchase a single common share in the Company. Holders of stock options shall be entitled to exercise the vested portion of the stock option during the time period as determined by the Board, provided that a qualified exit, as defined in the 2020 Plan, has occurred. If a qualified exit, as defined in the 2020 Plan, occurs then all of the holders unvested options shall vest immediately. Options that are not exercised during the exercise period will automatically be forfeited. Stock options generally vest over a four-year In October 2020, the Board approved the 2020 Equity Incentive Plan or (“2020 Equity Plan”). The 2020 Equity Plan allowed the Company to award up to 1,625,858 options and the 2,512,427 outstanding options granted under the 2020 Plan were transferred to the 2020 Equity Plan and no further options were available to be issued under the 2020 Plan. The 2020 Equity Plan will cumulatively increase by 5 percent of the number of shares of common stock issued and outstanding on January 1 st The following table sets forth the activity for the Company’s stock options during the periods presented: Number of Options Weighted- average exercise price per share Weighted- average remaining contractual term (in years) Aggregate intrinsic value Outstanding at December 31, 2019 304,142 $ 5.58 — — Granted 2,235,285 4.67 — — Exercised (1,016 ) 1.95 — — Outstanding at December 31, 2020 2,538,411 4.67 8.8 $ 20,009,769 Granted 1,631,000 9.49 — 8,160 Cancelled (170,683 ) 7.63 — — Outstanding at December 31, 2021 3,998,728 $ 6.51 8.3 $ 1,357,655 Vested and expected to vest at December 31, 2021 3,694,586 $ 6.60 7.2 $ 855,324 Vested and exercisable at December 31, 2021 1,439,589 $ 4.13 7.2 $ 855,324 The weighted-average grant date fair value of all stock options granted during the year ended December 31, 2021 was $7.01. The intrinsic value at December 31, 2021 and 2020 is based on the closing price of the Company’s common stock on that date of $3.03 and $12.51 per share, respectively. Stock-based compensation The following table summarizes the Company’s stock-based compensation expense for the year-ended December 31, 2021 and 2020 (in thousands): For the Year Ended December 31, 2021 2020 Research and development $ 1,903 $ 420 General and administrative 2,577 589 Total Stock-based compensation $ 4,480 $ 1,009 The fair value of stock options vested during the year ended December 31, 2021 was $2.6 million. At December 31, 2021, there was $12.5 million of unrecognized stock-based compensation expense relating to stock options granted pursuant to the 2020 Plan, which will be The fair values of the options granted were estimated based on the Black-Scholes model, using the following assumptions: 2021 2020 Risk-free interest rate 0.7 % 0.4 % Expected term (in years) 6.0 5.8 Expected volatility 90.5 % 90.1 % Expected dividend yield 0 % 0 %

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2021
Income Tax Disclosure [Abstract]
Income Taxes	12. INCOME TAXES The Company had no income tax expense or benefit for the years ended December 31, 2021 and 2020. The Company has incurred net operating losses for all the periods presented. The Company has not reflected the benefit of any such net operating loss carryforwards in the accompanying financial statements. As of December 31, 2019, the domicile of the reporting entity has changed from Denmark to the United States resulting in a tax rate of 21% in 2021 and 2020. This is discussed further below. The components of net loss are as follows (in thousands): Year Ended December 31, 2021 2020 Domestic $ (11,252 ) $ (7,544 ) Foreign (40,500 ) (27,293 ) Total $ (51,752 ) $ (34,837 ) Reconciliation of Effective Tax Rate The effective tax rate for the years ended December 31, 2021 and 2020 is different from the statutory rate primarily due to the valuation allowance against deferred tax assets as a result of insufficient sources of income. The reconciliation of the statutory income tax rate to the Company’s effective income tax rate is as follows: Year Ended December 31, 2021 2020 Income tax benefit at the statutory rate 21.0 % 21.0 % State income taxes 1.3 2.9 Permanent differences 3.5 2.5 Research and development tax credits — 2.3 Foreign rate differential 0.8 0.8 Orphan Drug Credit 5.7 — Other — — Change in valuation allowance (32.3 ) (29.5 ) Total — % — % Deferred taxes Deferred income taxes reflect the net effects of temporary differences between the carrying amounts of assets and liabilities for financial reporting purposes and the amounts used for income tax purposes. The principal components of the Company’s deferred tax assets consisted of the following (in thousands): December 31, Deferred tax assets: 2021 2020 Net operating loss carryforwards $ 31,022 $ 18,471 U.S. research and development credits 1,191 2,019 Foreign research and development credits — 809 Orphan drug credit 3,948 — Bonus compensation 274 322 Total deferred tax assets $ 36,435 $ 21,621 Valuation allowance (36,435 ) (21,621 ) Net deferred tax assets $ — $ — In assessing the realizability of deferred tax assets, management considers whether it is more-likely-than-not that some portion or all of the deferred tax assets will not be realized. The Company regularly assesses the likelihood that the deferred tax assets will be recovered from future taxable income. The Company considers projected future taxable income and ongoing tax planning strategies, then records a valuation allowance to reduce the carrying value of the net deferred taxes to an amount that is more-likely-than-not able to be realized. Based upon the Company’s assessment of all available evidence, including the previous three years of taxable income and loss after permanent items, estimates of future profitability, and the Company’s overall prospects of future business, the Company determined that it is more-likely-than-not that the Company will not be able to realize a portion of the deferred tax assets in the future. The Company will continue to assess the potential realization of deferred tax assets on an annual basis, or an interim basis if circumstances warrant. If the Company’s actual results and updated projections vary significantly from the projections used as a basis for this determination, the Company may need to change the valuation allowance against the gross deferred tax assets. On the basis of this evaluation, a full valuation allowance at December 31, 2021 and December 31, 2020 was recorded of $36.4 million and $21.6 million, respectively, to reduce the net deferred tax assets to their estimated realizable value. The change in valuation allowance was $14.8 million. The Company is subject to taxation in the United States, United Kingdom, Denmark and Sweden. As of December 31, 2021, tax years 2018 and forward were generally open to examination by the Danish tax authorities and tax year 2020 and forward was open to examination by the United States tax authorities. The Company is not under examination by any taxing authorities. As of December 31, 2021, the Company had gross U.S. federal net operating losses, or NOLs, of $21.7 million and federal research and development credits, or R&D credits, of $1.2 million and Orphan Drug Credit, or ODC, of $3.9 million to offset tax liabilities. The federal R&D credit and ODC carryforwards begin to expire in 2033 and 2042, respectively. All of the federal NOLs have an infinite life. The Company also had gross state NOLs of $17.4 million, The Company recognizes accrued interest related to unrecognized tax benefits and penalties as income tax expense. The Company does not have any material unrecognized tax benefits which would affect the effective tax rate if recognized. The Company does not have any unrecognized tax benefits which would reverse within the next twelve months. The Company is eligible for the Danish enhanced research and development tax allowance, providing for an increase in the deductible value of the amount of certain R&D expenditures. The deduction for R&D expenditures is set at 101.5% for 2019, 130% for 2020 through 2022, 108% for 2023 through 2025 and 110% for 2026.

Net Loss Per Share

Net Loss Per Share	12 Months Ended
	Dec. 31, 2021
Earnings Per Share [Abstract]
Net Loss Per Share	13. NET LOSS PER SHARE Basic and diluted net loss per share is calculated as follows (in thousands except share and per share amounts): Year Ended December 31, 2021 2020 Net loss $ (51,752 ) $ (34,837 ) Net loss per common share, basic and diluted $ (2.05 ) $ (7.62 ) Weighted-average number of shares used in computing net loss per common share, basic and diluted 25,261,832 4,572,702 The following outstanding potentially dilutive securities have been excluded from the calculation of diluted net loss per share, as their effect is anti-dilutive: Year Ended December 31, 2021 2020 Stock options to purchase common stock 3,998,728 2,538,411

Defined Contribution Plan

Defined Contribution Plan	12 Months Ended
	Dec. 31, 2021
Compensation And Retirement Disclosure [Abstract]
Defined Contribution Plan	14. DEFINED CONTRIBUTION PLAN During the year ended December 31, 2021, the Company established a 401(k)-defined contribution plan (the “401(k) Plan”) for its U.S. based employees. Eligible employees may make pretax contributions to the 401(k) Plan up to statutory limits. At the discretion of its Board, the Company may elect to match employee contributions. For the year ended December 31, 2021, the Company paid a match of up to 6%, up to the maximum permitted by the Internal Revenue Code, which amounted to $0.1 million, which is expensed as personnel costs when incurred.

Related Party Transactions

Related Party Transactions	12 Months Ended
	Dec. 31, 2021
Related Party Transactions [Abstract]
Related Party Transactions	15. RELATED PARTY TRANACTIONS During the year ended December 31, 2021 and 2020, the Company had no material related party transactions.

Subsequent Events

Subsequent Events	12 Months Ended
	Dec. 31, 2021
Subsequent Events [Abstract]
Subsequent Events	16. SUBSEQUENT EVENTS The Company has evaluated subsequent events through the date on which the consolidated financial statements were issued. The Company has concluded that no subsequent events have occurred that require disclosure to the consolidated financial statements.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2021
Accounting Policies [Abstract]
Basis of presentation	Basis of presentation The accompanying consolidated financial statements have been prepared in conformity with United States, or U.S., generally accepted accounting principles, or GAAP. Any reference in these notes to applicable guidance is meant to refer to U.S. GAAP, as found in the Accounting Standards Codification, or ASC, and Accounting Standards Update, or ASU, of the Financial Accounting Standards Board, or FASB.
Principles of consolidation	Principles of consolidation The Company’s consolidated financial statements for 2021 and 2020 include Galecto, Inc. and its subsidiaries. All intercompany balances and transactions have been eliminated in 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, disclosure of contingent assets and liabilities at the date of the consolidated financial statements, and the reported amounts of expenses during the reporting periods. The Company bases its estimates on historical experience and various other assumptions that management believes to be reasonable under the circumstances. Significant items subject to such estimates and assumptions include contract research accruals, accounting for stock-based compensation and valuation of the Company’s deferred tax assets. Changes in estimates are recorded in the period in which they become known. The Company’s actual results could differ from those estimates.
Currency and currency translation	Currency and currency translation The consolidated financial statements are presented in U.S. dollars, the Company’s reporting currency. Galecto, Inc., Galecto Securities Corporation and PharmAkea’s functional currency is the U.S. dollar. The functional currency of the Company’s subsidiary Galecto Biotech AB, and its subsidiary Galecto Biotech ApS, is the Euro. Adjustments that arise from exchange rate changes on transactions of each group entity denominated in a currency other than the functional currency are included in other income and expense in the consolidated statements of operations. Assets and liabilities of Galecto Biotech AB and Galecto Biotech ApS recorded in their Euro functional currency are translated into the U.S. dollar reporting currency of the Company at the exchange rate on the balance sheet date. Revenue and expenses of Galecto Biotech AB and Galecto Biotech ApS recorded in their Euro functional currency are translated into the U.S. dollar reporting currency of the Company at the average exchange rate prevailing during the year. Resulting translation adjustments are recorded to accumulated other comprehensive income (loss), or OCI.
Cash and cash equivalents	Cash and cash equivalents The Company considers all highly liquid investments with original maturities at the date of purchase of three months or less to be cash equivalents. Cash and cash equivalents are stated at fair value and may include money market funds, U.S. Treasury and U.S. government-sponsored agency securities, corporate debt, commercial paper and certificates of deposit. The Company had money market funds of $49.6 and $142.9 million as of December 31, 2021 and 2020, respectively, which are included in cash and cash equivalents and reported at fair value (Note 4).
Restricted cash	Restricted cash The Company is required to maintain cash collateral on deposit in a segregated money market bank account, as a condition of its security deposit with one of its banks for the use of corporate credit cards. As of December 31, 2020, the Company presented restricted cash in the accompanying consolidated balance sheets of $0.3 million. There was no restricted cash as of December 31, 2021.
Concentrations of credit risk and off-balance sheet risk	Concentrations of credit risk and off-balance sheet risk Financial instruments that subject the Company to significant concentrations of credit risk consist primarily of cash, cash equivalents, restricted cash and marketable securities. Substantially all of the Company’s cash is held at financial institutions that management believes to be of high-credit quality. The Company maintains its cash in bank deposit and checking accounts that at times exceed insured limits. The Company has not experienced any losses in such accounts and believes it is not exposed to any significant credit risk.
Investments in Marketable Securities	Investments in Marketable Securities The Company invests excess cash balances in short-term and long-term marketable debt securities. The Company classifies investments in marketable debt securities as either held-to-maturity or available-for-sale based on the facts and circumstances present at the time of purchase and re-evaluates classification at each balance sheet date. All investments in marketable debt securities at each balance sheet date presented, are generally considered as available-for-sale. Marketable debt securities with maturities of twelve months or less are classified as short-term investments and marketable debt securities with maturities greater than twelve months are classified based on their availability for use in current operations. The Company reports available-for-sale debt securities at fair value at each balance sheet date and includes any unrealized holding gains and losses (the adjustment to fair value), net of applicable taxes, in accumulated other comprehensive income (loss), a component of stockholders’ equity. The cost of debt securities is adjusted for the amortization of premium and accretion of discounts to maturity. Such amortization and accretion is included in interest income.
Fair value of financial instruments	Fair value of financial instruments Fair value is defined as the price the Company would receive to sell an investment in a timely transaction or pay to transfer a liability in a timely transaction with an independent buyer in the principal market, or in the absence of a principal market, the most advantageous market for the investment or liability. A framework is used for measuring fair value utilizing a three-tier hierarchy that prioritizes the inputs to valuation techniques used to measure fair value. The hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (Level 1) and the lowest priority to unobservable inputs (Level 3). The three levels of the fair value hierarchy are as follows: Level 1 —Unadjusted quoted prices in active markets that are accessible at the measurement date for identical, unrestricted assets or liabilities; Level 2 —Quoted prices in markets that are not considered to be active or financial instrument valuations for which all significant inputs are observable, either directly or indirectly; and Level 3 —Prices or valuations that require inputs that are both significant to the fair value measurement and unobservable. Financial instruments are categorized in their entirety based on the lowest level of input that is significant to the fair value measurement. The assessment of the significance of a particular input to the fair value measurement requires judgment and considers factors specific to the investment. To the extent that the valuation is based on models or inputs that are less observable or unobservable in the market, the determination of fair value requires more judgment. Accordingly, the degree of judgment exercised by us in determining fair value is greatest for instruments categorized in Level 3. The Company monitors the availability of inputs that are significant to the measurement of fair value to assess the appropriate categorization of financial instruments within the fair value hierarchy. Changes in economic conditions or model-based valuation techniques may require the transfer of financial instruments from one fair value level to another. In such instances, our policy is to recognize significant transfers between levels at the end of the reporting period. The significance of transfers between levels is evaluated based upon the nature of the financial instrument and size of the transfer relative to total net assets available for benefits.
Leases	Leases The Company determines whether an arrangement is or contains a lease at the time it enters into a contract. For all leases, the Company determines the classification as either operating leases or finance leases. Operating leases are included in operating lease right-of-use, or ROU, assets and accrued expenses and other current liabilities and operating lease liabilities, noncurrent in the Company’s consolidated balance sheets. The Company has not entered into any financing leases. Lease recognition occurs at the commencement date and lease liability amounts are based on the present value of lease payments over the lease term. The lease terms may include options to extend or terminate the lease when it is reasonably certain that the Company will exercise that option. If a lease does not provide information to determine an implicit interest rate, the Company uses the Company’s incremental borrowing rate in determining the present value of lease payments. ROU assets represent the right to use an underlying asset for the lease term, and lease liabilities represent the obligation to make lease payments under the lease. ROU assets also include any lease payments made prior to the commencement date and exclude lease incentives received. Operating lease expense is recognized on a straight-line basis over the lease term. The depreciable life of assets and leasehold improvements are limited by the expected lease term, unless there is a transfer of title or purchase option reasonably certain of exercise. Lease agreements with both lease and non-lease components, are generally accounted for together as a single lease component. Refer to Note 6 for further details.
Property and Equipment, Net	Property and Equipment, Net Property and equipment are recorded at cost. Costs associated with maintenance and repairs are expensed as incurred. Depreciation is provided using the straight-line method over the estimated useful lives: Asset Category Useful Life Equipment 5-7 years Furniture and fixtures 5 years Leasehold improvements Lesser of 10 years or the remaining term of the respective lease
Impairment of Long-Lived Assets	Impairment of Long-Lived Assets Long-lived assets to be held and used are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of the asset may not be recoverable. When such events occur, the Company compares the carrying amounts of the assets to their undiscounted expected future cash flows. If the undiscounted cash flows are insufficient to recover the carrying value, an impairment loss is recorded for the difference between the carrying value and fair value of the asset. Through December 31, 2021 , no such impairment has occurred.
Research and development expenses	Research and development expenses Research and development costs are expensed as incurred. The Company’s research and development expenses consist primarily of costs incurred for the development of its product candidates and include expenses incurred under agreements with contract manufacturing organizations, or CMOs, contract research organizations, or CROs, investigative sites and consultants to conduct clinical trials and preclinical and non-clinical studies, costs to acquire, develop and manufacture supplies for clinical trials and other studies, salaries and related costs, including stock-based compensation, depreciation The Company has met the requirements to receive a tax credit in Denmark for losses resulting from research and development costs of up to $3.8 million and $4.1 million for the years ended December 31, 2021 and 2020, respectively. The tax credit is reported as a reduction to research and development expense in the consolidated statements of operations. For the years ended December 31, 2021 and 2020, research and development expenses include refundable tax credits of $0.9 million and $0.8 million, respectively.
Accrued research and development costs	Accrued research and development costs Substantial portions of the Company’s preclinical and clinical trials are performed by third-party laboratories, medical centers, CROs and other vendors, or collectively, CROs. These CROs generally bill monthly for services performed, or bill based upon milestone achievement. For preclinical studies, the Company accrues expenses based upon estimated percentage of work completed and the contract milestones remaining. For clinical studies, expenses are accrued based upon the number of patients enrolled and the duration of the study. The Company monitors patient enrollment, the progress of clinical studies and related activities to the extent possible through internal reviews of data reported to the Company by the CROs, and correspondence with the CROs and clinical site visits. The Company’s estimates depend on the timeliness and accuracy of the data provided by the CROs regarding the status of each program and total program spending. The Company periodically evaluates the estimates to determine if adjustments are necessary or appropriate based on information it receives.
Convertible preferred stock	Convertible preferred stock The Company classifies convertible preferred stock outside of stockholders’ deficit on its consolidated balance sheet as the requirements of triggering a deemed liquidation event are not within the Company’s control. The Company records the issuance of convertible preferred stock at the issuance price less related issuance costs and less any discount arising on allocation of proceeds to one or more derivative features. In September 2020, the Company sold and issued 2,368,118 shares of Series D preferred stock for gross proceeds of $64.2 million, or $61.4 million net of $2.8 million in issuance costs. Immediately prior to consummation of, and in connection with, the Company’s IPO, all outstanding shares of the Company’s convertible preferred stock were converted into18,658,643 shares of common stock.
Stock-based compensation	Stock-based compensation The Company accounts for stock options granted in accordance with ASC 718, Compensation-Stock Compensation All share-based awards granted are measured based on the fair value on the date of the grant and compensation expense is recognized with respect to those awards over the requisite service period, which is generally the vesting period of the respective award. The Company reverses any previously recognized compensation cost associated with forfeited awards in the period the forfeiture occurs. Equity-based compensation expense is classified in the Company’s consolidated statement of operations and comprehensive loss in the same manner in which the award recipients’ payroll costs are classified or in which the award recipients’ service payments are classified. The fair value of each stock option grant is estimated on the date of grant using the Black-Scholes model. The following summarizes the inputs used: Expected volatility —The Company estimates its expected stock volatility based on the historical volatility of a publicly traded set of peer companies because we lack company-specific historical and implied volatility information due in part to the limited time in which we have operated as a publicly traded company. We expect to continue to do so until such time as we have adequate historical data regarding the volatility of our traded stock price. Expected term —The expected term of the Company’s stock options has been determined based on the expected time to liquidity. The Company uses the simplified method prescribed by the SEC’s Staff Accounting Bulletin No. 107, Share-Based Payment , to calculate the expected term of options granted because we lack company-specific historical and implied expected term information due in part to the limited time in which we have operated as a publicly traded company . Risk-free interest rate —The risk-free interest rate is based on the implied yield on a U.S. Treasury security at a constant maturity with a remaining term equal to the expected term of the option granted. Dividends —Expected dividend yield is zero because the Company does not pay cash dividends on common shares and does not expect to pay any cash dividends in the foreseeable future.
Income taxes	Income taxes Deferred income tax assets and liabilities arise from temporary differences associated with differences between the financial statements and tax basis of assets and liabilities, as measured by the enacted tax rates, which are expected to be in effect when these differences reverse. Valuation allowances are established when necessary to reduce deferred tax assets to the amount expected to be realized. The Company has generated net losses since inception and accordingly has not recorded a provision for income taxes. The Company follows the provisions of ASC 740-10, Uncertainty in Income Taxes, The Company has identified the United States, Denmark, United Kingdom and Sweden as its major tax jurisdictions. Refer to Note 12 for further details.
Net loss per share	Net loss per share Basic net loss per share is computed by dividing the net loss by the weighted-average number of shares of common stock outstanding for the period. Diluted net loss per share is computed by dividing the net loss by the weighted-average number of shares of common stock and dilutive common stock equivalents outstanding for the period, determined using the treasury-stock method and the as if-converted method, for convertible securities, if inclusion of these instruments is dilutive. For the years ended December 31, 2021 and 2020, both methods are equivalent. Basic and diluted net loss per share is described further in Note 13.
Segments	Segments Operating segments are defined as components of an entity for which separate financial information is available and that is regularly reviewed by the chief operating decision maker, or CODM, in deciding how to allocate resources to an individual segment and in assessing performance. The Company’s CODM is its chief executive officer. The Company has determined it operates in one segment.
Other comprehensive gain (loss)	Other comprehensive gain (loss) Other comprehensive gain (loss), or OCI, is defined as the change in equity of a business enterprise during a period from transactions and other events and circumstances from non-owner sources. The Company’s OCI includes currency translation and unrealized gain or (loss) on marketable securities.
Emerging growth company status	Emerging growth company status The Company is an emerging growth company, as defined in the Jumpstart Our Business Startups Act of 2012, or JOBS Act. Under the JOBS Act, emerging growth companies can delay adopting new or revised accounting standards issued subsequent to the enactment of the JOBS Act, until such time as those standards apply to private companies. The Company may elect to use this extended transition period for complying with new or revised accounting standards that have different effective dates for public and private companies until the earlier of the date that it (i) is no longer an emerging growth company or (ii) affirmatively and irrevocably opts out of the extended transition period provided in the JOBS Act. As a result, and as a smaller reporting company, these financial statements may not be comparable to companies that comply with the new or revised accounting pronouncements as of public company effective dates.
Recently adopted accounting standards and Recently issued accounting standards	Recently adopted accounting standards In December 2019, the FASB issued ASU No. 2019-12, Simplifying the Accounting for Income Taxes Recently issued accounting standards In June 2016, the FASB issued ASU No. 2016-13, Financial Instruments-Credit Losses: Measurement of Credit Losses on Financial Instruments Codification Improvements to Topic 326, Financial Instruments-Credit Losses, Topic 815, Derivatives and Hedging and Topic 825, Financial Instruments

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2021
Accounting Policies [Abstract]
Summary of Estimated Useful Life of Asset	Property and equipment are recorded at cost. Costs associated with maintenance and repairs are expensed as incurred. Depreciation is provided using the straight-line method over the estimated useful lives: Asset Category Useful Life Equipment 5-7 years Furniture and fixtures 5 years Leasehold improvements Lesser of 10 years or the remaining term of the respective lease

Investments in Marketable Sec_2

Investments in Marketable Securities (Tables)	12 Months Ended
	Dec. 31, 2021
Investments Debt And Equity Securities [Abstract]
Summary of Available-for-Sale Investments	A summary of the Company’s available-for-sale investments as of December 31, 2021 consisted of the following (in thousands): At December 31, 2021 Amortized Gross Unrealized Gross Unrealized Fair Marketable securities: Cost Gains Losses Value Corporate bonds $ 37,671 $ — $ (43 ) $ 37,628 Total $ 37,671 $ — $ (43 ) $ 37,628 Marketable securities, non-current: Corporate bonds $ 9,082 $ — $ (34 ) $ 9,048 Total $ 9,082 $ — $ (34 ) $ 9,048

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	12 Months Ended
	Dec. 31, 2021
Fair Value Disclosures [Abstract]
Summary of Assets Measured at Fair Value	A summary of the assets that are measured at fair value as of December 31, 2021 and 2020 is as follows (in thousands): Fair Value Measurement at December 31, 2021 Assets: Carrying Value Quoted Prices in Active Markets for Identical Assets (Level 1) Significant other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Money market funds (1) $ 49,626 $ 49,626 $ — $ — Debt securities 46,676 — 46,676 — Total $ 96,302 $ 49,626 $ 46,676 $ — Fair Value Measurement at December 31, 2020 Assets: Carrying Value Quoted Prices in Active Markets for Identical Assets (Level 1) Significant other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Money market funds (1) $ 142,904 $ 142,904 $ — $ — Total $ 142,904 $ 142,904 $ — $ — (1) Money market funds with maturities of 90 days or less at the date of purchase are included within cash and cash equivalents in the accompanying consolidated balance sheets and are recognized at fair value.

Prepaid Expenses and Other Cu_2

Prepaid Expenses and Other Current Assets (Tables)	12 Months Ended
	Dec. 31, 2021
Prepaid Expense And Other Assets Current [Abstract]
Schedule of Prepaid Expenses and Other Current Assets	Prepaid expenses and other current assets consist of the following (in thousands): December 31, 2021 2020 Contract research and development costs $ 5,569 $ 1,620 Prepaid insurance costs 1,728 1,642 Research and development tax credit receivable 1,682 1,808 Value-added tax refund receivable 598 401 Other 334 242 Total prepaid expenses and other current assets $ 9,911 $ 5,713

Leases (Tables)

Leases (Tables)	12 Months Ended
	Dec. 31, 2021
Leases [Abstract]
Summary of Operating Leases	The Company has the following operating leases: Location Primary Use Lease Expiration Date Renewal Option Copenhagen, Denmark Corporate headquarters January 2025 None London, United Kingdom Office space August 2022 None Gothenburg, Sweden Office space May 2023 None Stevenage, United Kingdom Laboratory space January 2024 None
Quantitative Information Regarding Leases	Quantitative information regarding the Company’s leases for the years ended December 31, 2021 and 2020 is as follows (in thousands): Year Ended December 31, Lease Cost: 2021 2020 Operating lease cost $ 496 $ 213 Other Information: Operating cash flows paid for amounts included in the measurement of lease liabilities $ 513 $ 213 Operating lease liabilities arising from obtaining right-of-use assets $ 411 $ 713
Summary of Operating Lease Liabilities	Operating lease liabilities are as follows at December 31, 2021 (in thousands): Operating Leases 2022 $ 442 2023 273 2024 204 2025 17 2026 — Total lease payments 936 Less: imputed interest (90 ) Total lease liabilities $ 846

Equipment, Net (Tables)

Equipment, Net (Tables)	12 Months Ended
	Dec. 31, 2021
Property Plant And Equipment [Abstract]
Summary of Equipment	E quipment as of December 31, 2021 consisted of the following (in thousands): December 31, 2021 Equipment $ 223 Less: accumulated depreciation (20 ) Equipment, net $ 203

Accrued Expenses And Other Cu_2

Accrued Expenses And Other Current Liabilities (Tables)	12 Months Ended
	Dec. 31, 2021
Payables And Accruals [Abstract]
Schedule of Accrued Expenses and Other Current Liabilities	Accrued expenses and other current liabilities consist of the following (in thousands): December 31, 2021 2020 Contract research and development costs $ 1,575 $ 967 Employee compensation costs 601 1,031 Lease liabilities, current 399 374 Other current liabilities 438 343 Total accrued expenses and other current liabilities $ 3,013 $ 2,715

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	12 Months Ended
	Dec. 31, 2021
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Summary of Stock Options Activity	The following table sets forth the activity for the Company’s stock options during the periods presented: Number of Options Weighted- average exercise price per share Weighted- average remaining contractual term (in years) Aggregate intrinsic value Outstanding at December 31, 2019 304,142 $ 5.58 — — Granted 2,235,285 4.67 — — Exercised (1,016 ) 1.95 — — Outstanding at December 31, 2020 2,538,411 4.67 8.8 $ 20,009,769 Granted 1,631,000 9.49 — 8,160 Cancelled (170,683 ) 7.63 — — Outstanding at December 31, 2021 3,998,728 $ 6.51 8.3 $ 1,357,655 Vested and expected to vest at December 31, 2021 3,694,586 $ 6.60 7.2 $ 855,324 Vested and exercisable at December 31, 2021 1,439,589 $ 4.13 7.2 $ 855,324
Summary of Stock-based Compensation Expense	The following table summarizes the Company’s stock-based compensation expense for the year-ended December 31, 2021 and 2020 (in thousands): For the Year Ended December 31, 2021 2020 Research and development $ 1,903 $ 420 General and administrative 2,577 589 Total Stock-based compensation $ 4,480 $ 1,009
Summary of Fair Value Assumptions of Options Granted Estimated Based on Black-Scholes Model	The fair values of the options granted were estimated based on the Black-Scholes model, using the following assumptions: 2021 2020 Risk-free interest rate 0.7 % 0.4 % Expected term (in years) 6.0 5.8 Expected volatility 90.5 % 90.1 % Expected dividend yield 0 % 0 %

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2021
Income Tax Disclosure [Abstract]
Summary of Components of Net Loss	The components of net loss are as follows (in thousands): Year Ended December 31, 2021 2020 Domestic $ (11,252 ) $ (7,544 ) Foreign (40,500 ) (27,293 ) Total $ (51,752 ) $ (34,837 )
Schedule of Reconciliation of Statutory Income Tax Rate to Effective Income Tax Rate	. The reconciliation of the statutory income tax rate to the Company’s effective income tax rate is as follows: Year Ended December 31, 2021 2020 Income tax benefit at the statutory rate 21.0 % 21.0 % State income taxes 1.3 2.9 Permanent differences 3.5 2.5 Research and development tax credits — 2.3 Foreign rate differential 0.8 0.8 Orphan Drug Credit 5.7 — Other — — Change in valuation allowance (32.3 ) (29.5 ) Total — % — %
Schedule of Components of Company's Deferred Tax Assets	The principal components of the Company’s deferred tax assets consisted of the following (in thousands): December 31, Deferred tax assets: 2021 2020 Net operating loss carryforwards $ 31,022 $ 18,471 U.S. research and development credits 1,191 2,019 Foreign research and development credits — 809 Orphan drug credit 3,948 — Bonus compensation 274 322 Total deferred tax assets $ 36,435 $ 21,621 Valuation allowance (36,435 ) (21,621 ) Net deferred tax assets $ — $ —

Net Loss Per Share (Tables)

Net Loss Per Share (Tables)	12 Months Ended
	Dec. 31, 2021
Earnings Per Share [Abstract]
Schedule of Basic and Diluted Net Loss Per Share	Basic and diluted net loss per share is calculated as follows (in thousands except share and per share amounts): Year Ended December 31, 2021 2020 Net loss $ (51,752 ) $ (34,837 ) Net loss per common share, basic and diluted $ (2.05 ) $ (7.62 ) Weighted-average number of shares used in computing net loss per common share, basic and diluted 25,261,832 4,572,702
Schedule of Antidilutive Securities Excluded from Calculation of Diluted Net Loss Per Share	The following outstanding potentially dilutive securities have been excluded from the calculation of diluted net loss per share, as their effect is anti-dilutive: Year Ended December 31, 2021 2020 Stock options to purchase common stock 3,998,728 2,538,411

Description of Business, Orga_2

Description of Business, Organization and Liquidity - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Description Of Business Organization And Liquidity [Line Items]
Accumulated deficit	$ 156,112,000	$ 104,360,000
Net loss	(51,752,000)	(34,837,000)
Cash, cash equivalents and marketable securities	109,200
Cash and cash equivalents	62,563,000	163,582,000
Current assets	110,102,000	169,295,000
Current liabilities	4,544,000	5,566,000
Clinical Development and Corporate General and Administrative Activities
Description Of Business Organization And Liquidity [Line Items]
Net loss	$ (52,300,000)	$ (38,200,000)

Summary of Significant Accoun_4

Summary of Significant Accounting Policies - Additional Information (Details)	9 Months Ended	12 Months Ended
	Sep. 30, 2020USD ($)shares	Dec. 31, 2021USD ($)Segmentshares	Dec. 31, 2020USD ($)shares
Summary Of Significant Accounting Policies [Line Items]
Original maturities at the date of purchase of liquid investments		three months or less
Money market funds		$ 49,600,000	$ 142,900,000
Restricted cash		$ 0	$ 300,000
Preferred stock, issued (in shares) | shares		0	0
Expected dividend yield		$ 0
Number of operating segments | Segment		1
Series D Convertible Preferred Stock
Summary Of Significant Accounting Policies [Line Items]
Preferred stock, issued (in shares) | shares	2,368,118
Proceeds from issuance of preferred stock	$ 64,200,000
Proceeds from issuance or sale of equity	61,400,000
Payments of stock issuance costs	$ 2,800,000		$ 2,840,000
Conversion of convertible preferred stock into common stock (in shares) | shares	18,658,643
Research and Development
Summary Of Significant Accounting Policies [Line Items]
Refundable tax credit		$ 3,800,000	4,100,000
Tax credit refund receivable		$ 900,000	$ 800,000

Summary of Significant Accoun_5

Summary of Significant Accounting Policies - Summary of Estimated Useful Life of Asset (Detail)	12 Months Ended
	Dec. 31, 2021
Equipment | Minimum
Property Plant And Equipment [Line Items]
Estimated useful life of asset	5 years
Equipment | Maximum
Property Plant And Equipment [Line Items]
Estimated useful life of asset	7 years
Furniture and Fixtures
Property Plant And Equipment [Line Items]
Estimated useful life of asset	5 years
Leasehold Improvements
Property Plant And Equipment [Line Items]
Estimated useful life of asset	Lesser of 10 years or the remaining term of the respective lease

Investments in Marketable Sec_3

Investments in Marketable Securities - Summary of Available-for-Sale Investments (Details) - USD ($)	Dec. 31, 2021	Dec. 31, 2020
Schedule of Available for Sale Securities [Line Items]
Fair Value		$ 0
Debt Securities Available For Sales Type Extensible List	us-gaap:CorporateDebtSecuritiesMember
Investments - Current
Schedule of Available for Sale Securities [Line Items]
Amortized Cost	$ 37,671,000
Gross Unrealized Losses	(43,000)
Fair Value	37,628,000
Investments - Noncurrent
Schedule of Available for Sale Securities [Line Items]
Amortized Cost	9,082,000
Gross Unrealized Losses	(34,000)
Fair Value	$ 9,048,000

Investments in Marketable Sec_4

Investments in Marketable Securities - Additional Information (Details)	Dec. 31, 2020USD ($)
Investments Debt And Equity Securities [Abstract]
Investments in marketable securities	$ 0

Fair Value Measurements - Summa

Fair Value Measurements - Summary of Assets Measured at Fair Value (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets fair value	$ 96,302	$ 142,904
Money Market Funds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets fair value	49,626	142,904
Debt Securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets fair value	46,676
Level 1
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets fair value	49,626	142,904
Level 1 | Money Market Funds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets fair value	49,626	$ 142,904
Level 2
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets fair value	46,676
Level 2 | Debt Securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets fair value	$ 46,676

Prepaid Expenses and Other Cu_3

Prepaid Expenses and Other Current Assets - Schedule of Prepaid Expenses and Other Current Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Prepaid Expense And Other Assets Current [Abstract]
Contract research and development costs	$ 5,569	$ 1,620
Prepaid insurance costs	1,728	1,642
Research and development tax credit receivable	1,682	1,808
Value-added tax refund receivable	598	401
Other	334	242
Total prepaid expenses and other current assets	$ 9,911	$ 5,713

Leases - Summary of Operating L

Leases - Summary of Operating Leases (Details)	12 Months Ended
	Dec. 31, 2021
Copenhagen, Denmark
Operating Leased Assets [Line Items]
Operating lease, expiration date	Jan. 31, 2025
Operating lease,renewal option	None
London,United Kingdom
Operating Leased Assets [Line Items]
Operating lease, expiration date	Aug. 31, 2022
Operating lease,renewal option	None
Stevenage, United Kingdom
Operating Leased Assets [Line Items]
Operating lease, expiration date	Jan. 31, 2024
Operating lease,renewal option	None
Gothenburg, Sweden
Operating Leased Assets [Line Items]
Operating lease, expiration date	May 31, 2023
Operating lease,renewal option	None

Leases - Additional Information

Leases - Additional Information (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Leases [Abstract]
Rent expense	$ 0.5	$ 0.2
Weighted average remaining lease term for operating leases	2 years 4 months 24 days	2 years 9 months 18 days
Weighted average discount rate for operating leases	8.00%	8.00%

Leases - Quantitative Informati

Leases - Quantitative Information Regarding Leases (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Lease Cost:
Operating lease cost	$ 496	$ 213
Operating cash flows paid for amounts included in the measurement of lease liabilities	513	213
Operating lease liability arising from obtaining right-of-use assets	$ 411	$ 713

Leases - Summary of Operating_2

Leases - Summary of Operating Lease Liabilities (Details) $ in Thousands	Dec. 31, 2021USD ($)
Operating Leases
2022	$ 442
2023	273
2024	204
2025	17
Total lease payments	936
Less: imputed interest	(90)
Total lease liabilities	$ 846

Equipment, Net - Summary of Equ

Equipment, Net - Summary of Equipment (Details) $ in Thousands	Dec. 31, 2021USD ($)
Property Plant And Equipment [Abstract]
Equipment	$ 223
Less: accumulated depreciation	(20)
Equipment, net	$ 203

Equipment, Net - Additional Inf

Equipment, Net - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Property Plant And Equipment [Abstract]
Depreciation expense	$ 20,000
Equipment		$ 0

Accrued Expenses and Other Cu_3

Accrued Expenses and Other Current Liabilities - Schedule of Accrued Expenses and Other Current Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Payables And Accruals [Abstract]
Contract research and development costs	$ 1,575	$ 967
Employee compensation costs	601	1,031
Lease liabilities, current	$ 399	$ 374
Operating Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]	Lease liabilities, current	Lease liabilities, current
Other current liabilities	$ 438	$ 343
Total accrued expenses and other current liabilities	$ 3,013	$ 2,715

Stockholders' Equity - Addition

Stockholders' Equity - Additional Information (Details) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended		12 Months Ended
	Nov. 30, 2020	Oct. 31, 2020	Dec. 31, 2021	Dec. 31, 2020
Subsidiary Sale Of Stock [Line Items]
Common stock, authorized		300,000,000	300,000,000	300,000,000
Preferred stock, authorized		10,000,000	10,000,000	10,000,000
Common stock, outstanding			25,261,832	25,261,832
Common stock, dividends per share declared			$ 0
Common stock, dividends per share paid			$ 0
Initial Public Offering
Subsidiary Sale Of Stock [Line Items]
Issuance of common stock in connection with initial public offering, net of issuance costs (in shares)		6,342,207
Stock issued during period, price per shares		$ 15
Shares granted to underwriters	675,540
Stock issued during period, net proceeds		$ 86.3

Stock-Based Compensation - Addi

Stock-Based Compensation - Additional Information (Details) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended		12 Months Ended
	Oct. 31, 2020	Mar. 31, 2020	Dec. 31, 2021	Dec. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of options, granted			1,631,000	2,235,285
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average grant date fair value of stock options granted			$ 7.01
Intrinsic value per share of stock options			$ 3.03	$ 12.51
Fair value of stock options vested			$ 2.6
2020 Plan | Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of options, granted		304,142
Stock options, vesting period		4 years
Stock options, expiration period		10 years
2020 Equity Incentive Plan | Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of options, granted	2,512,427
Percentage increase of number of shares of common stock issued and outstanding	5.00%
Stock options available for future grant			1,401,632
Unrecognized compensation expense			$ 12.5
Unrecognized compensation expense that is expected to be recognized over a weighted-average period			2 years 10 months 24 days
Maximum | 2020 Plan | Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of stock options allowed to award		1,740,325
Maximum | 2020 Equity Incentive Plan | Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of stock options allowed to award	1,625,858

Stock-Based Compensation - Summ

Stock-Based Compensation - Summary of Stock Options Activity (Details) - USD ($)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Number of Options, Outstanding	2,538,411	304,142
Number of Options, Granted	1,631,000	2,235,285
Number of Options, Exercised		(1,016)
Number of Options, Cancelled	(170,683)
Number of Options, Outstanding	3,998,728	2,538,411	304,142
Number of Options, Vested and expected to vest	3,694,586
Number of Options, Vested and exercisable	1,439,589
Weighted average exercise price per share, Outstanding	$ 4.67	$ 5.58
Weighted average exercise price per share, Granted	9.49	4.67
Weighted average exercise price per share, Exercised		1.95
Weighted average exercise price per share, Cancelled	7.63
Weighted average exercise price per share, Outstanding	6.51	$ 4.67	$ 5.58
Weighted average exercise price per share, Vested and expected	6.60
Weighted average exercise price per share, Vested and exercisable	$ 4.13
Weighted average remaining contractual term (in years), Outstanding	8 years 3 months 18 days	8 years 9 months 18 days	0 years
Weighted average remaining contractual term (in years), Vested and expected to vest	7 years 2 months 12 days
Weighted average remaining contractual term (in years), Vested and exercisable	7 years 2 months 12 days
Aggregate intrinsic value, Outstanding	$ 20,009,769
Aggregate intrinsic value, Granted	8,160
Aggregate intrinsic value, Outstanding	1,357,655	$ 20,009,769
Aggregate intrinsic value, Vested and expected to vest	855,324
Aggregate intrinsic value, Vested and exercisable	$ 855,324

Stock-Based Compensation - Su_2

Stock-Based Compensation - Summary of Stock-based Compensation Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total Stock-based compensation	$ 4,480	$ 1,009
Research and Development
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total Stock-based compensation	1,903	420
General and Administrative
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total Stock-based compensation	$ 2,577	$ 589

Stock-Based Compensation - Su_3

Stock-Based Compensation - Summary of Fair Value Assumptions of Options Granted Estimated Based on Black-Scholes Model (Details)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Risk-free interest rate	0.70%	0.40%
Expected term (in years)	6 years	5 years 9 months 18 days
Expected volatility	90.50%	90.10%
Expected dividend yield	0.00%	0.00%

Income Taxes - Additional Infor

Income Taxes - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Operating Loss Carryforwards [Line Items]
Income tax expense or benefit	$ 0	$ 0
Tax rate	21.00%	21.00%
Valuation allowance	$ 36,435,000	$ 21,621,000
Change in valuation allowance	14,800,000
Orphan drug credit	$ 3,948,000
Operating loss carryforwards, Limitations on Use	The Company also had NOLs in Denmark of $115.3 million which have an indefinite life. Federal and state NOLs and R&D credit and ODC carryforwards are also subject to annual limitations in the event that cumulative changes in the ownership interests of significant stockholders exceed 50% over a three-year period, as defined under Sections 382 and 383 of the Internal Revenue Code of 1986.
Research and Development
Operating Loss Carryforwards [Line Items]
Tax allowance			101.50%
2020 through 2022 | Research and Development
Operating Loss Carryforwards [Line Items]
Tax allowance		130.00%
2023 through 2025 | Research and Development
Operating Loss Carryforwards [Line Items]
Tax allowance		108.00%
2026 | Research and Development
Operating Loss Carryforwards [Line Items]
Tax allowance		110.00%
Federal
Operating Loss Carryforwards [Line Items]
Net operating loss carryforwards	$ 21,700,000
Research and Development tax credits	1,200,000
Orphan drug credit	3,900,000
State
Operating Loss Carryforwards [Line Items]
Net operating loss carryforwards	17,400,000
Denmark
Operating Loss Carryforwards [Line Items]
Net operating loss carryforwards	$ 115,300,000

Income Taxes - Summary of Compo

Income Taxes - Summary of Components of Net Loss (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Income Tax Disclosure [Abstract]
Domestic	$ (11,252)	$ (7,544)
Foreign	(40,500)	(27,293)
Total	$ (51,752)	$ (34,837)

Income Taxes - Schedule of Reco

Income Taxes - Schedule of Reconciliation of Statutory Income Tax Rate to Effective Income Tax Rate (Details)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Income Tax Disclosure [Abstract]
Tax rate	21.00%	21.00%
State income taxes	1.30%	2.90%
Permanent differences	3.50%	2.50%
Research and development tax credits		2.30%
Foreign rate differential	0.80%	0.80%
Orphan Drug Credit	5.70%
Change in valuation allowance	(32.30%)	(29.50%)

Income Taxes - Schedule of Comp

Income Taxes - Schedule of Components of Company's Deferred Tax Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Deferred tax assets:
Net operating loss carryforwards	$ 31,022	$ 18,471
U.S. research and development credits	1,191	2,019
Bonus compensation	274	322
Total deferred tax assets	36,435	21,621
Foreign research and development credits		809
Orphan drug credit	3,948
Valuation allowance	$ (36,435)	$ (21,621)

Net Loss Per Share - Schedule o

Net Loss Per Share - Schedule of Basic and Diluted Net Loss Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Earnings Per Share [Abstract]
Net loss	$ (51,752)	$ (34,837)
Net loss per common share, basic and diluted	$ (2.05)	$ (7.62)
Weighted-average number of shares used in computing net loss per common share, basic and diluted	25,261,832	4,572,702

Net Loss Per Share - Schedule_2

Net Loss Per Share - Schedule of Antidilutive Securities Excluded from Calculation of Diluted Net Loss Per Share (Details) - shares	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Stock Options to Purchase Common Stock
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share	3,998,728	2,538,411

Defined Contribution Plan - Add

Defined Contribution Plan - Additional Information (Details) $ in Millions	12 Months Ended
	Dec. 31, 2021USD ($)
Defined Contribution Plan Disclosure [Line Items]
Contribution paid by employer	$ 0.1
Maximum
Defined Contribution Plan Disclosure [Line Items]
Employer matching contribution	6.00%

Related Party Transactions - Ad

Related Party Transactions - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Related Party Transactions [Abstract]
Related party transactions	$ 0	$ 0