Theseus Pharmaceuticals (THRX) 10-Q 12 May 22 2022 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2022	May 02, 2022
Document and Entity Information [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Mar. 31, 2022
Document Transition Report	false
Entity File Number	001-40869
Entity Registrant Name	THESEUS PHARMACEUTICALS, INC.
Entity Tax Identification Number	83-0712806
Entity Address State Or Province	MA
Entity Address, Address Line One	314 Main Street
Entity Address, City or Town	Cambridge
Entity Incorporation, State or Country Code	DE
Entity Address, Postal Zip Code	02142
City Area Code	857
Local Phone Number	400-9491
Title of 12(b) Security	Common Stock, $0.0001 par value per share
Trading Symbol	THRX
Security Exchange Name	NASDAQ
Entity Current Reporting Status	No
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		38,702,650
Entity Central Index Key	0001745020
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2022
Document Fiscal Period Focus	Q1
Amendment Flag	false

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Current assets:
Cash and cash equivalents	$ 146,281	$ 244,662
Short-term investments	85,757
Prepaid expenses and other current assets	2,914	3,309
Total current assets	234,952	247,971
Property and equipment, net	37	11
Obtaining a right-of-use asset in exchange for an operating lease liability	4,721
Long-term investments	4,945
Other assets	2,850	2,947
Total assets	247,505	250,929
Current liabilities:
Accounts payable	1,425	1,002
Accrued expenses and other current liabilities	2,779	2,678
Operating lease liability, current portion	1,179
Total current liabilities	5,383	3,680
Operating lease liability, net of current portion	3,542
Restricted stock liability, net of current portion	728	815
Total liabilities	9,653	4,495
Commitments and contingencies (Note 8)
Stockholders' equity (deficit):
Common stock, $0.0001 par value; 500,000,000 and 29,054,797 shares authorized as of December 31, 2021 and December 31, 2020, respectively; 38,702,650 and 1,708,625 shares issued and outstanding as of December 31, 2021 and December 31, 2020, respectively	4	4
Additional paid-in capital	310,052	308,008
Accumulated deficit	(72,075)	(61,578)
Accumulated other comprehensive loss	(129)
Total stockholders' equity (deficit)	237,852	246,434
Total liabilities, redeemable convertible preferred stock and stockholders' equity (deficit)	$ 247,505	$ 250,929

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - $ / shares	Mar. 31, 2022	Dec. 31, 2021
Consolidated Balance Sheets
Common stock, par value	$ 0.0001	$ 0.0001
Common stock, shares authorized	500,000,000	500,000,000
Common stock, shares issued	38,702,650	38,702,650
Common stock, shares outstanding	38,702,650	1,708,625
Preferred stock, par value	$ 0.0001	$ 0.0001
Preferred stock, shares authorized	50,000,000	50,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0

Consolidated Statements of Oper

Consolidated Statements of Operations and Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Operating expenses:
Research and development	$ 6,548	$ 3,825
General and administrative	4,031	664
Total operating expenses	10,579	4,489
Loss from operations	(10,579)	(4,489)
Other income (expense), net:
Other income, net	82	16
Total other income (expense), net	82	16
Net loss	(10,497)	(4,473)
Unrealized loss on investments	(129)
Comprehensive loss	(10,626)	(4,473)
Net loss attributable to common stockholders-basic (Note 13)	(10,497)	(4,473)
Net loss attributable to common stockholders- diluted (Note 13)	$ (10,497)	$ (4,473)
Net loss per share attributable to common stockholders-basic	$ (0.27)	$ (4.90)
Net loss per share attributable to common stockholders- diluted	$ (0.27)	$ (4.90)
Weighted-average common stock outstanding-basic	38,247,970	912,222
Weighted-average common stock outstanding- diluted	38,247,970	912,222

Consolidated Statements of Rede

Consolidated Statements of Redeemable Convertible Preferred Stock and Stockholders' Equity (Deficit) - USD ($) $ in Thousands	SERIES A REDEEMABLE CONVERTIBLE PREFERRED STOCK	SERIES B REDEEMABLE CONVERTIBLE PREFERRED STOCK	COMMON STOCK	ADDITIONAL PAID-IN CAPITAL	ACCUMULATED OTHER COMPREHENSIVE LOSS	ACCUMULATED DEFICIT	Total
Beginning balance at Dec. 31, 2020	$ 41,289
Beginning balance, shares at Dec. 31, 2020	16,734,179
Increase (Decrease) in Temporary Equity
Issuance of redeemable convertible preferred stock, net of issuance costs		$ 99,892
Issuance of redeemable convertible preferred stock, net of issuance costs, shares		8,741,726
Ending balance at Mar. 31, 2021	$ 41,289	$ 99,892
Ending balance, shares at Mar. 31, 2021	16,734,179	8,741,726
Beginning balance at Dec. 31, 2020						$ (34,270)	$ (34,270)
Beginning balance, shares at Dec. 31, 2020			882,789
Increase (Decrease) in Stockholders' Equity
Vesting of restricted stock, shares			85,430
Stock-based compensation				$ 548			548
Net loss						(4,473)	(4,473)
Ending balance at Mar. 31, 2021				548		(38,743)	(38,195)
Ending balance, shares at Mar. 31, 2021			968,219
Beginning balance at Dec. 31, 2021			$ 4	308,008		(61,578)	246,434
Beginning balance, shares at Dec. 31, 2021			37,872,604
Increase (Decrease) in Stockholders' Equity
Vesting of restricted stock, shares			85,431
Stock-based compensation				2,044			2,044
Unrealized loss on investments					$ (129)		(129)
Net loss						(10,497)	(10,497)
Ending balance at Mar. 31, 2022			$ 4	$ 310,052	$ (129)	$ (72,075)	$ 237,852
Ending balance, shares at Mar. 31, 2022			37,958,035

Consolidated Statements of Re_2

Consolidated Statements of Redeemable Convertible Preferred Stock and Stockholders' Equity (Deficit) (Parenthetical) $ in Thousands	3 Months Ended
	Mar. 31, 2021USD ($)
Consolidated Statements of Redeemable Convertible Preferred Stock and Stockholders' Equity (Deficit)
Payment of issuance costs	$ 208

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($)	3 Months Ended
	Mar. 31, 2022	Jun. 30, 2021	Mar. 31, 2021
Cash flows from operating activities:
Net loss	$ (10,497,000)		$ (4,473,000)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation expense	1,000		1,000
Amortization and accretion of investments	2,000
Non-cash interest income	(162,000)
Stock-based compensation expense	2,044,000	$ (500,000)	548,000
Changes in operating assets and liabilities:
Prepaid expenses and other current assets	394,000		(1,545,000)
Accounts payable	423,000		(122,000)
Accrued expenses and other current liabilities	13,000		348,000
Other assets	98,000		43,000
Net cash used in operating activities	(7,684,000)		(5,200,000)
Cash flows from investing activities:
Purchases of short-term and long-term investments	(90,670,000)
Purchases of property and equipment	(27,000)
Net cash used in investing activities	(90,697,000)
Cash flows from financing activities:
Net cash provided by financing activities			99,892,000
Net increase in cash and cash equivalents	(98,381,000)		94,692,000
Cash and cash equivalents at beginning of year	245,041,000	$ 103,149,000	8,457,000
Cash and cash equivalents at end of period	146,660,000		103,149,000
Supplemental disclosure of cash flows:
Obtaining a right-of-use asset in exchange for an operating lease liability	4,721,000
Operating lease liability	$ 4,721,000
SERIES B REDEEMABLE CONVERTIBLE PREFERRED STOCK
Cash flows from financing activities:
Proceeds from issuance redeemable convertible preferred stock, net of issuance costs			$ 99,892,000

Consolidated Statements of Ca_2

Consolidated Statements of Cash Flows (Parenthetical) $ in Thousands	Mar. 31, 2022USD ($)
Cash, cash equivalents, and restricted cash balances:
Cash and cash equivalents	$ 146,281
Restricted cash (included in other assets)	379
Total cash, cash equivalents, and restricted cash	$ 146,660

Nature of the Business

Nature of the Business	3 Months Ended
	Mar. 31, 2022
Nature of the Business
Nature of the Business	1. Nature of the Business Theseus Pharmaceuticals, Inc. (“Theseus” or the “Company”) is a clinical-stage biopharmaceutical company focused on improving the lives of cancer patients through the discovery, development and commercialization of transformative targeted therapies. The Company was incorporated in December 2017 under the laws of the State of Delaware, and its principal offices are in Cambridge, Massachusetts. Reverse Stock Split On September 27, 2021, the Company effected a one-for-1.32286 reverse stock split of shares of the Company’s common stock and convertible preferred stock. All of the share and per share amounts included in the accompanying condensed consolidated financial statements and notes thereto have been retroactively adjusted for all periods presented to give effect to this reverse stock split, including reclassifying an amount equal to the reduction in par value of common stock to additional paid-in capital. Shares of common stock underlying outstanding stock options were proportionately reduced and the respective exercise prices, if applicable, were proportionately increased in accordance with the terms of the appropriate securities agreements. Stockholders entitled to fractional shares as a result of the reverse stock split received a cash payment in lieu of receiving fractional shares. Initial Public Offering On October 12, 2021, the Company closed the initial public offering (“IPO”), in which it sold 10,000,200 shares of common stock at a public offering price of $16.00 per share. On October 25, 2021, the underwriters partially exercised their option to purchase an additional 1,171,990 shares of common stock at the public offering price of $16.00 per share. After deducting underwriting discounts, commissions and offering expenses, the aggregate net offering proceeds raised in the IPO were approximately $162.5 million. Upon the closing of the IPO, all of the Company’s outstanding shares of redeemable convertible preferred stock automatically converted into an aggregate of 25,475,905 shares of common stock. In connection with the closing of the IPO, the Company amended and restated its certificate of incorporation to among other things: (a) authorize 500,000,000 shares of voting common stock; (b) eliminate all references to the previously existing series of redeemable convertible preferred stock; and (c) authorize 50,000,000 shares of preferred stock that may be issued from time to time by the Company’s board of directors (the “Board”) in one or more series. Basis of Presentation The Company’s condensed consolidated financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America (“U.S. GAAP”). Any reference in these notes to applicable guidance is meant to refer to the authoritative U.S. GAAP as found in the ASC and Accounting Standards Update (“ASU”) of the Financial Accounting Standards Board (“FASB”). The accompanying condensed consolidated financial statements and footnotes to the condensed consolidated financial statements have been prepared on the same basis as the most recently audited annual consolidated financial statements and, in the opinion of management, reflect all normal recurring adjustments necessary for the fair presentation of the Company’s financial position as of March 31, 2022 and the results of its operations and its cash flows for the three-month periods ended March 31, 2022 and 2021. The results for the three-month period ended March 31, 2022 are not necessarily indicative of results to be expected for the year ending December 31, 2022, any other interim periods, or any future year or period. These condensed consolidated financial statements should be read in conjunction with the Company’s audited consolidated financial statements and the notes thereto for the year ended December 31, 2021. In connection with the preparation of its financial statements for the three months ended March 31, 2022, the Company identified an immaterial revision related to the presentation of stock-based compensation expense in the Condensed Consolidated Statements of Redeemable Convertible Preferred Stock and Stockholders’ Equity (Deficit) for each of the three-months ended June 30, 2021 and March 31, 2021. This revision impacts only stock-based compensation expense reported in the Condensed Consolidated Statements of Redeemable Convertible Preferred Stock and Stockholders’ Equity (Deficit), and has no impact on the Company’s other previously reported financial statements. The effect of the revision was a decrease in stock-based compensation expense of $0.5 million for the three months ended June 30, 2021 (previously reported $1,440; as adjusted to $936), and an increase in stock-based compensation expense of $0.5 million for the three months ended March 31, 2021 (previously reported $44; as adusted $548). Liquidity The Company is subject to risks and uncertainties common to early-stage companies in the biotechnology industry, including but not limited to, development by competitors of new technological innovations, dependence on key personnel, protection of proprietary technology, compliance with government regulations and the ability to secure additional capital to fund operations. The Company’s development programs 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 and infrastructure and extensive compliance-reporting capabilities. Because of the numerous risks and uncertainties associated with product development, the Company is unable to predict the timing or amount of increased expenses or when or if the Company will be able to achieve or maintain profitability. Even if the Company is able to generate revenue from product sales, the Company may not become profitable. If the Company fails to become profitable or is unable to sustain profitability on a continuing basis, then the Company may be unable to continue its operations at planned levels and be forced to reduce or terminate its operations. The Company expects to incur substantial operating losses and negative cash flows from operations for the foreseeable future. In accordance with Accounting Standards Codification (“ASC”) 205-40, Going Concern

Summary of Significant Accounti

Summary of Significant Accounting Policies	3 Months Ended
	Mar. 31, 2022
Summary of Significant Accounting Policies
Summary of Significant Accounting Policies	2. Summary of Significant Accounting Policies The significant accounting policies and estimates used in the preparation of the accompanying condensed consolidated financial statements are described in the Company’s audited consolidated financial statements, which were included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2021, filed with the Securities and Exchange Commission (“SEC”) on March 10, 2022 (“Annual Report”). There have been no material changes in the Company’s significant accounting policies during the three months ended March 31, 2022, except as noted below. Unaudited Interim Financial Information The accompanying condensed consolidated financial statements and the accompanying notes as of March 31, 2022 and December 31, 2021 and for the three-month periods ended March 31, 2022 and 2021 are unaudited. The condensed consolidated interim financial statements have been prepared on the same basis as the audited annual consolidated financial statements and, in the opinion of management, reflect all adjustments, which include only normal recurring adjustments necessary for the fair presentation of the Company’s financial position as of March 31, 2022 and the results of its operations for the three-month periods ended March 31, 2022 and 2021 and its cash flows for the three months ended March 31, 2022 and 2021. Use of Estimates The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of expenses during the reporting periods. Estimates and judgments are based on historical information and other market-specific or various relevant assumptions, including in certain circumstances, future projections, that management believes to be reasonable under the circumstances. Actual results could differ materially from estimates. Significant estimates and assumptions are used for, but not limited to, the accruals for research and development expenses, the incremental borrowing rate for determining the operating lease right-of-use (“ROU”) asset and lease liabilities, and for periods prior to the completion of the IPO, the determination of fair value of equity instruments, and the fair value of the preferred stock tranche rights and the anti-dilution right, and stock-based compensation expense. Concentration of Credit Risk Financial instruments that potentially expose the Company to concentrations of credit risk consist primarily of cash, cash equivalents, and investments. Periodically, the Company maintains deposits in accredited financial institutions in excess of federally insured limits. The Company deposits its cash in financial institutions that it believes have high credit quality and have not experienced any losses on such accounts and does not believe it is exposed to any unusual credit risk beyond the normal credit risk associated with commercial banking relationships. Such deposits have and will continue to exceed federally insured limits. The Company has not experienced any losses on its cash deposits. The Company’s short-term and long-term investments are invested in high grade securities with limited concentration in any one issuer, and as a result, the Company believes represent minimal credit risk. Fair Value of Financial Instruments The Company categorizes its assets and liabilities measured at fair value in accordance with ASC Topic 820, Fair Value Measurement determined based on assumptions that market participants would use in pricing an asset or liability. As a basis for considering such assumptions, ASC 820 establishes a three-tier fair value hierarchy, which prioritizes the inputs used in measuring fair value as follows: ● Level 1—Unadjusted quoted prices in active markets that are accessible at the measurement date for identical assets or liabilities; ● Level 2—Quoted prices for similar assets and liabilities in active markets, quoted prices in markets that are not active, or inputs which are observable, either directly or indirectly, for substantially the full term of the asset or liability; or ● Level 3—Prices or valuation techniques that require inputs that are both significant to the fair value measurement and unobservable (i.e., supported by little or no market activity). Investments All investments have been classified as “available-for-sale” and are carried at fair value as determined based upon quoted market prices or pricing models for similar securities at period end. Investments with contractual maturities less than 12 months at the balance sheet date are considered short-term investments. Those investments with contractual maturities 12 months or greater at the balance sheet date are considered long-term investments. Dividend and interest income are recognized in the Company’s condensed consolidated statements of operations and comprehensive loss when earned. Realized gains and losses are included in earnings and are derived using the specific identification method for determining the cost of securities sold. Unrealized gains and losses are reported as a component of accumulated other comprehensive income (loss). The cost of the Company’s available-for-sale debt securities is adjusted for amortization of premium and accretion of discounts to maturity. The Company reviews its portfolio of available-for-sale debt securities, using both quantitative and qualitative factors, to determine if declines in fair value below cost have resulted from a credit-related loss or other factors. If the decline in fair value is due to credit-related factors, a loss is recognized in statements of operations, whereas if the decline in fair value is not due to credit-related factors, the loss is recorded in other comprehensive income (loss). Leases Prior to January 1, 2021, the Company accounted for leases in accordance with FASB Accounting Standards Codification (“ASC”) ASC 840, Leases Effective on January 1, 2021, the Company accounts for leases in accordance with ASC Topic 842, Leases (“ASC 842”). In accordance with ASC 842, the Company determines whether an arrangement is or contains a lease at inception. A contract is or contains a lease if the contract conveys the right to control the use of an identified asset for a period of time in exchange for consideration. The Company classifies leases at the lease commencement date, when control of the underlying asset is transferred from the lessor to the Company, as operating or finance leases and records a ROU asset and a lease liability on the consolidated balance sheet for all real-estate leases with an initial lease term of greater than 12 months. Leases with a lease term of 12 months or less are not recorded on the balance sheet, but payments are recognized as expense on a straight-line basis over the lease term. A lease qualifies as a finance lease if any of the following criteria are met at the inception of the lease: (i) there is a transfer of ownership of the leased asset to the Company by the end of the lease term, (ii) the Company holds an option to purchase the leased asset that it is reasonably certain to exercise, (iii) the lease term is for a major part of the remaining economic life of the leased asset, (iv) the present value of the sum of lease payments equals or exceeds substantially all of the fair value of the leased asset, or (v) the nature of the leased asset is specialized to the point that it is expected to provide the lessor no alternative use at the end of the lease term. All other leases are recorded as operating leases. The Company enters into contracts that contain both lease and non-lease components. Non-lease components may include maintenance, utilities, and other operating costs. For all real estate asset classes, the Company combines the lease and non-lease components of fixed costs in its lease arrangements as a single lease component. Variable costs, such as utilities or maintenance costs, are not included in the measurement of ROU assets and lease liabilities, but rather are expensed when the event determining the amount of variable consideration to be paid occurs. Finance and operating lease assets and liabilities are recognized at the lease commencement date based on the present value of the lease payments over the lease term using the discount rate implicit in the lease. If the rate implicit is not readily determinable, the Company utilizes an estimate of its incremental borrowing rate based upon the available information at the lease commencement date. ROU assets are further adjusted for initial direct costs, prepaid rent, or incentives received. Operating lease payments are expensed using the straight-line method as an operating expense over the lease term. The Company’s lease terms may include options to extend or terminate the lease when it is reasonably certain that the Company will exercise that option. Finance lease assets are amortized to depreciation expense using the straight-line method over the shorter of the useful life of the related asset or the lease term. Finance lease payments are bifurcated into (i) a portion that is recorded as interest expense and (ii) a portion that reduces the finance liability associated with the lease. Comprehensive Loss Comprehensive loss includes net loss as well as other changes in stockholders’ equity (deficit) that result from transactions and economic events other than those with stockholders, including unrealized gains and losses on investments. The unrealized losses on investments represent the only component of other comprehensive loss that is excluded from the reported net loss. Recently Issued and Adopted Accounting Pronouncements From time to time, new accounting pronouncements are issued by the FASB or other standard setting bodies and adopted by the Company as of the specified effective date. Unless otherwise discussed, the Company believes that the impact of recently issued standards that are not yet effective will not have a material impact on its condensed consolidated financial statements and disclosures. The recently issued and adopted accounting pronouncements pertaining to the Company are disclosed in the Company’s audited consolidated financial statements for the year ended December 31, 2021, which were included in the Company’s Annual Report. Since the date of those financial statements, there have been no changes.

Fair Value of Financial Assets

Fair Value of Financial Assets and Liabilities	3 Months Ended
	Mar. 31, 2022
Fair Value of Financial Assets and Liabilities
Fair Value of Financial Assets and Liabilities	3. Fair Value of Financial Assets and Liabilities The carrying values of other current assets, accounts payable, and accrued expenses approximate their fair values due to the short-term nature of these instruments. The Company’s investments, which may include both short-term and long-term investment securities consisting of high-quality, marketable debt instruments of corporations are measured at fair value in accordance with the fair value hierarchy. A ssets measured at fair value on a recurring basis as of March 31, 2022 are as follows (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ FAIR VALUE MEASUREMENTS AT MARCH 31, 2022 ​ ​ LEVEL 1 ​ LEVEL 2 ​ LEVEL 3 ​ TOTAL Cash equivalents: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Money market funds $ 29,249 ​ $ — ​ $ — ​ $ 29,249 Investments: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Commercial paper ​ ​ — ​ ​ 25,344 ​ ​ — ​ ​ 25,344 Corporate debt securities ​ ​ — ​ ​ 41,425 ​ ​ — ​ ​ 41,425 Asset-backed securities ​ ​ — ​ ​ 1,997 ​ ​ — ​ ​ 1,997 Government securities ​ ​ — ​ ​ 21,936 ​ ​ — ​ ​ 21,936 Total financial assets ​ $ 29,249 ​ $ 90,702 ​ $ — ​ $ 119,951 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ During the year ended December 31, 2021, there were no assets or liabilities measured at fair value. During the three months ended March 31, 2022 and the year ended December 31, 2021 , there were no transfers between fair value levels.

Investments

Investments	3 Months Ended
	Mar. 31, 2022
Investments
Investments	4. Investments The Company’s investment policy defines allowable investments and establishes guidelines relating to credit quality, diversification, and maturities of its investments to preserve principal and maintain liquidity. In accordance with the Company’s investment policy, it has invested funds in marketable securities as of March 31, 2022. The Company’s investments are classified as available-for-sale investments. The cost, gross unrealized holding gains, gross unrealized holding losses and fair value of investments by types and classes of security at March 31, 2022 consisted of the following (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ MARCH 31, 2022 ​ MATURITY ​ AMORTIZED ​ UNREALIZED ​ UNREALIZED ​ FAIR ​ IN YEARS COST GAIN LOSS VALUE Commercial paper less than 1 ​ $ 25,344 ​ $ — ​ $ — ​ $ 25,344 Corporate debt securities less than 1 ​ ​ 36,550 ​ ​ — ​ ​ (70) ​ ​ 36,480 Asset-backed securities less than 1 ​ ​ 2,005 ​ ​ — ​ ​ (8) ​ ​ 1,997 Government securities less than 1 ​ ​ 21,945 ​ ​ 2 ​ ​ (11) ​ ​ 21,936 Short-term investments ​ ​ $ 85,844 ​ $ 2 ​ $ (89) ​ $ 85,757 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Corporate debt securities 1 - 2 ​ ​ 4,987 ​ ​ — ​ ​ (42) ​ ​ 4,945 Long-term investments ​ ​ $ 4,987 ​ $ — ​ $ (42) ​ $ 4,945 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ The Company reviews its investments to identify and evaluate investments that have an indication of possible other-than-temporary impairment. Factors considered in determining whether a loss is other-than-temporary include the length of time and extent to which fair value has been less than the cost basis, the financial condition and near-term prospects of the investee, and the Company’s intent and ability to hold the investment for a period of time sufficient to allow for any anticipated recovery in market value. At March 31, 2022, the Company did not have any securities in material unrealized loss positions. The Company generally does not intend to sell any investments prior to recovery of their amortized cost basis for any investment in an unrealized loss position. Further, such investments are invested in high grade securities. As such, the Company has classified these losses as temporary in nature. The Company has determined that there were no material declines in fair value of its investments due to credit-related factors as of March 31, 2022.

Property and Equipment, net

Property and Equipment, net	3 Months Ended
	Mar. 31, 2022
Property and Equipment, net
Property and Equipment, net	5. Property and Equipment, net Property and equipment, net consisted of the following as of March 31, 2022 and as of December 31, 2021 (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ MARCH 31, DECEMBER 31, ​ ​ 2022 ​ 2021 Computer equipment ​ $ 39 ​ $ 12 Less: accumulated depreciation ​ (2) ​ (1) Property and equipment, net ​ $ 37 ​ $ 11 ​ ​ ​ ​ ​ ​ ​ ​ Depreciation expense for each of the three-month periods ended March 31, 2022 and 2021 was approximately $1,000 . There were no impairments recorded to date.

License Agreement

License Agreement	3 Months Ended
	Mar. 31, 2022
License Agreement
License Agreement	6. License Agreements During the three months ended March 31, 2022, there were no changes to the Company’s license agreement with ARIAD Pharmaceuticals, Inc. (“ARIAD”). For a summary of the terms of the license agreement, including the Company’s accounting treatment, please refer to Note 7 to the Company’s audited consolidated financial statements for the year ended December 31, 2021, included in the Company’s Annual Report.

Leases

Leases	3 Months Ended
	Mar. 31, 2022
Leases
Leases	7. Leases On July 19, 2021, the Company entered into a lease agreement for office space in Cambridge, Massachusetts, on a month-to-month basis, which was determined to be a short-term lease as the Company was not reasonably certain to extend the lease beyond twelve months. The Company recognizes lease payments as incurred over the lease term, and recognized short-term lease expense of $0.1 million for the three months ended March 31, 2022. On September 16, 2021, the Company entered into an operating lease agreement for 7,351 rentable square feet of office space located in Cambridge, Massachusetts. The premises required additional build-out at the time the lease agreement was entered into. The lease commenced in March 2022 when the space was made available for use. Upon lease commencement, the Company recorded a ROU asset of $4.7 million and a corresponding lease liability of $4.7 million. The lease has a term of 7 years and an expiration date of March 22, 2029, with lease payments made on a monthly basis. The initial annual base rent is approximately $0.8 million, subject to a 3% annual rent increase, plus an allocation of the Company’s proportionate share of building operating costs such as maintenance, utilities, and insurance that are treated as variable costs and excluded from the measurement of the lease. The Company is entitled to one option to extend the lease term for an additional period of five years . The option to extend the lease term is not reflected in the ROU asset and lease liability as it is not reasonably certain of being exercised. Pursuant to the terms of the lease, the Company provided a security deposit in the form of a letter of credit in the amount of approximately $0.4 million upon signing, which is recognized as restricted cash within other assets on the condensed consolidated balance sheets. As of March 31, 2022, the weighted-average remaining lease term was 7 years, and the weighted-average discount rate was 9.1%. The following table presents future lease payments under the terms of the Company’s operating leases as of March 31, 2022, including a reconciliation to the present value of operating lease liabilities recognized in the condensed consolidated balance sheet (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ Remainder of 2022 ​ $ 1,024 2023 ​ ​ 774 2024 ​ ​ 797 2025 ​ ​ 821 2026 ​ ​ 846 Thereafter ​ ​ 1,995 Total future minimum lease payments ​ ​ 6,257 Less: imputed interest ​ ​ (1,536) Present value of lease liabilities ​ $ 4,721 ​ ​ ​ ​ ​

Commitments and Contingencies

Commitments and Contingencies	3 Months Ended
	Mar. 31, 2022
Commitments and Contingencies.
Commitments and Contingencies	8. Commitments and Contingencies Legal Proceedings The Company may from time to time be party to litigation arising in the ordinary course of business. The Company was not subject to any material legal proceedings during the three months ended March 31, 2022 or the year ended December 31, 2021, and no material legal proceedings are currently pending or, to the best of the Company’s knowledge, threatened. Indemnification Agreements The Company enters into standard indemnification agreements in the ordinary course of business. Pursuant to the indemnification agreements, the Company agrees to indemnify, hold harmless, and to reimburse the indemnified party for losses suffered or incurred by the indemnified party, generally the Company’s business partners, in connection with any U.S. patent or any copyright or other intellectual property infringement claim by any third-party with respect to the Company’s products. The term of these indemnification agreements is generally perpetual any time after execution of the agreement. The maximum potential amount of future payments the Company could be required to make under these indemnification agreements is unlimited. The Company has never incurred costs to defend lawsuits or settle claims related to these indemnification agreements. 401(k) Plan The Company maintains a defined-contribution plan under Section 401(k) of the Internal Revenue Code of 1986 (the “401(k) Plan”). The 401(k) Plan covers all employees who meet defined minimum age and service requirements and allows participants to defer a portion of their annual compensation on a pre-tax basis. Matching contributions to the 401(k) Plan may be made at the discretion of management. The Company contributed $0.1 million to the 401(k) Plan during the three months ended March 31, 2022. There were no employer contributions made to the 401(k) Plan during the year ended December 31, 2021. ​ ​ ​ ​ ​ ​

Stockholders Equity

Stockholders Equity	3 Months Ended
	Mar. 31, 2022
Stockholders' Equity
Common Stock	9. Stockholders’ Equity Preferred Stock The Company was authorized to issue up to 50,000,000 shares of $0.0001 par value preferred stock as of March 31, 2022 and December 31, 2021, respectively. There were no shares of preferred stock outstanding as of March 31, 2022 and December 31, 2021, respectively. Common Stock The Company was authorized to issue 500,000,000 shares of $0.0001 par value common stock as of March 31, 2022 and as of December 31, 2021, respectively. The voting, dividend and liquidation rights of the holders of the Company’s common stock are subject to and qualified by the rights, powers and preference of the holders of any series of preferred stock. Voting Rights Each share of common stock entitles the holder to one vote on all matters submitted to the stockholders for a vote. Dividends Subject to preferences that may apply to shares of preferred stock outstanding at the time, the holders of outstanding shares of the Company’s common stock are entitled to receive dividends out of funds legally available if and when the Board, in its discretion, determines to issue dividends. As of March 31, 2022, no cash dividends have been declared or paid. Liquidation Rights Upon the Company’s dissolution, liquidation, or winding-up, the assets legally available for distribution to stockholders are distributable ratably among holders of the Company’s common stock, subject to prior satisfaction of all outstanding debt and liabilities, and the preferential rights and payment of liquidation preferences, if any, on any outstanding shares of preferred stock. ​

Stock-Based Compensation

Stock-Based Compensation	3 Months Ended
	Mar. 31, 2022
Stock-Based Compensation
Stock-Based Compensation	10. Stock-Based Compensation Equity Incentive Plans In September 2021, the Company adopted the Theseus Pharmaceuticals, Inc. 2021 Equity Incentive Plan (the “2021 Plan”), which replaced the 2018 Stock Incentive Plan (the “2018 Plan”) and allows for the issuance of stock options, restricted stock awards, restricted stock units (“RSUs”), and other types of equity awards. No further awards were made under the 2018 Plan as of the effective date of the 2021 Plan. Any options or awards outstanding under the 2018 Plan are governed by their existing terms. As of March 31, 2022 and December 31, 2021, the number of shares of common stock reserved for issuance was 9,094,083 shares for each such period end. Of those shares reserved for issuance, there were 2,237,340 and 3,930,440 shares available for future grant under the 2021 Plan as of March 31, 2022 and December 31, 2021, respectively. The 2021 Plan is administered by the Board (or its compensation committee), and the exercise prices, vesting and other restrictions for the awards are determined at the discretion of the Board, except that the exercise price per share of stock options may not be less than 100% of the fair market value of the common stock on the date of grant. Stock options awarded under the 2021 Plan expire ten years after the grant date unless the Board sets a shorter term. The expected term of stock options granted to employees and non-employees has been determined utilizing the “simplified” method for awards that qualify as “plain-vanilla” options. Stock options granted to employees and nonemployees typically vest over four years . Shares of restricted stock awards granted to employees, officers, members of the Board, advisors, and consultants of the Company typically vest over five years . Certain executives who are option holders are able to early exercise stock option awards prior to full satisfaction of the vesting conditions. If and when this occurs, the executive receives restricted common stock upon exercise of the option, and the shares remain subject to the Company’s right of repurchase until the remaining vesting terms are met. During the year ended December 31, 2021, 345,930 options to purchase common stock were exercised early. The Company recognized the proceeds received of $1.4 million as a liability as of December 31, 2021. There were no early exercises of options during the three months ended March 31, 2022. Employee Stock Purchase Plan The 2021 Employee Stock Purchase Plan (the “ESPP”) permits eligible employees who elect to participate in an offering under the ESPP to have up to 15% of their eligible earnings withheld, subject to certain limitations, to purchase shares of common stock pursuant to the ESPP. The price of common stock purchased under the ESPP is equal to 85% of the lower of the fair market value of the common stock at the commencement date of each offering period or the relevant date of purchase. The ESPP is implemented through a series of offering periods of up to 27 months, which may consist of one or more purchase periods. A total of 400,000 shares of common stock were initially reserved for issuance under the ESPP. Stock Option Valuation The assumptions that the Company used in Black-Scholes option-pricing model to determine the grant-date fair value of stock options granted are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ FOR THE THREE MONTHS ENDED FOR THE YEAR ENDED ​ ​ MARCH 31, 2022 ​ DECEMBER 31, 2021 Risk-free interest rate 1.60% - 2.16% ​ 1.07% Expected term (in years) 6.1 ​ 5.2 - 6.1 Expected volatility 78.00% - 78.90% ​ 75.58% - 83.56% Expected dividend yield 0.00% ​ 0.00% ​ ​ ​ ​ ​ ​ A summary of option activity under the 2021 Plan during the three months ended March 31, 2022 is as follows (in thousands except share, per share data and contractual terms): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ WEIGHTED-AVERAGE WEIGHTED-AVERAGE ​ ​ ​ ​ ​ PER-SHARE ​ REMAINING ​ AGGREGATE ​ ​ SHARES ​ EXERCISE PRICE ​ CONTRACTUAL TERM ​ INTRINSIC VALUE Outstanding as of December 31, 2021 ​ 5,163,643 ​ $ 4.31 9.29 ​ $ 44,463 Granted ​ 1,657,200 ​ 11.22 ​ Outstanding as of March 31, 2022 ​ 6,820,843 ​ $ 5.99 9.25 ​ 39,468 Options vested and exercisable as of March 31, 2022 ​ 844,039 ​ $ 1.43 8.83 ​ $ 8,566 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ The aggregate intrinsic value of stock options is calculated as the difference between the exercise price of the stock options and the fair value of the Company’s common stock for those stock options that had exercise prices lower than the fair value of the Company’s common stock. The weighted-average per share grant date fair value of options granted during the three months ended March 31, 2022 and 2021 was $7.68 and $5.46 , respectively. As of March 31, 2022, there was $31.5 million of unrecognized stock-based compensation expense related to unvested stock options. The unrecognized stock-based compensation expense is estimated to be recognized over a period of 3.1 years as of March 31, 2022. Restricted Stock Units The Company issues RSUs that generally vest over a four-year period with 25% of the RSUs vesting one year from the vesting commencement date, and the remainder vesting quarterly thereafter over the following 36 months. Any unvested shares will be forfeited upon termination of services. The fair value of an RSU is equal to the fair market value price of the Company’s common stock on the date of grant. A summary of RSU activity during the three months ended March 31, 2022 is as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ WEIGHTED-AVERAGE ​ ​ ​ ​ PER-SHARE GRANT-DATE ​ ​ SHARES ​ FAIR VALUE Unvested shares at December 31, 2021 — ​ $ — Granted 35,900 ​ 11.21 Unvested shares at March 31, 2022 35,900 ​ $ 11.21 ​ ​ ​ ​ ​ ​ ​ As of March 31, 2022, there was $0.4 million of unrecognized stock-based compensation expense related to unvested RSUs. The unrecognized stock-based compensation expense is estimated to be recognized over a period of 3.9 years as of March 31, 2022. Shares of Restricted Common Stock The Company issued shares of restricted common stock to its founders in May 2018, which vest monthly over five years through 2023. At issuance, these shares also contained certain performance-based vesting criteria which were associated with the milestone events applicable to the formerly outstanding shares of Series A preferred stock, two of which were achieved in 2020. In December 2020 in conjunction with the termination of the Series A preferred stock purchase agreement, the final performance-based vesting criteria was waived, leaving only service-based vesting criteria remaining for the founders’ shares through the end of the requisite service period, as of March 31, 2022. As noted above, certain executives who are option holders are able to early exercise stock option awards prior to full satisfaction of the vesting conditions. If and when such exercise occurs, the executive receives shares of restricted common stock. Early exercise shares are included in the table below. A summary of restricted common stock activity during the three months ended March 31, 2022 is as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ WEIGHTED-AVERAGE ​ ​ ​ ​ PER-SHARE GRANT-DATE ​ ​ SHARES ​ FAIR VALUE Unvested shares at December 31, 2021 830,046 ​ $ 2.85 Vested (85,431) ​ 0.83 Unvested shares at March 31, 2022 744,615 ​ $ 3.08 ​ ​ ​ ​ ​ ​ ​ As of March 31, 2022, there was $2.3 million of unrecognized stock-based compensation expense related to unvested restricted common stock. The unrecognized stock-based compensation expense is estimated to be recognized over a period of 2.0 years as of March 31, 2022. Stock-based Compensation Expense Total stock-based compensation expense recorded as research and development and general and administrative expenses, respectively, for employees, directors and non-employees during the three months ended March 31, 2022 and 2021 was as follows (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ THREE MONTHS ENDED MARCH 31, ​ 2022 2021 Research and development ​ $ 1,008 ​ $ 439 General and administrative ​ ​ 1,036 ​ ​ 109 ​ ​ $ 2,044 ​ $ 548 ​ ​ ​ ​ ​ ​ ​ ​

Income Taxes

Income Taxes	3 Months Ended
	Mar. 31, 2022
Income Taxes
Income Taxes	11. Income Taxes Income taxes for the three months ended March 31, 2022 and 2021 have been calculated based on an estimated annual effective tax rate and certain discrete items. For the three months ended March 31, 2022 and 2021, no income tax was recorded, as the Company recognized losses and maintains a full valuation allowance against its net deferred tax assets. The Company has never been examined by the Internal Revenue Service or any other jurisdiction for any tax years and, as such, all years within the applicable statutes of limitations are potentially subject to audit.

Net Loss Per Share

Net Loss Per Share	3 Months Ended
	Mar. 31, 2022
Net Loss Per Share
Net Loss Per Share	12. Net Loss Per Share Basic and diluted loss per share is computed by dividing net loss attributable to common stockholders by the weighted-average common shares outstanding (in thousands, except share and per share data): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ THREE MONTHS ENDED MARCH 31, ​ 2022 2021 Numerator: ​ ​ ​ ​ ​ ​ Net loss ​ $ (10,497) ​ $ (4,473) Net loss attributable to common stockholders - basic and diluted ​ $ (10,497) ​ $ (4,473) Denominator: ​ ​ ​ ​ Weighted-average common stock outstanding - basic and diluted ​ 38,247,970 ​ 912,222 Net loss per share attributable to common stockholders - basic and diluted ​ $ (0.27) ​ $ (4.90) ​ ​ ​ ​ ​ ​ ​ ​ The Company’s potentially dilutive securities, which include preferred stock, unvested restricted common stock, unvested RSUs and stock options, have been excluded from the computation of diluted net loss per share as the effect would be to reduce the net loss per share. Therefore, the weighted-average number of shares of common stock outstanding used to calculate both basic and diluted net loss per share attributable to common stockholders is the same. The Company excluded the following from the computation of diluted net loss per share attributable to common stockholders for the three months ended March 31, 2022 and 2021 because including them would have had an anti-dilutive effect: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ THREE MONTHS ENDED MARCH 31, ​ ​ 2022 2021 Preferred Stock ​ — ​ 25,475,905 ​ Unvested restricted stock 744,615 740,406 Unvested RSUs ​ 35,900 ​ — ​ Options to purchase common stock ​ 6,820,843 ​ 2,034,953 ​ ​ 7,601,358 28,251,264 ​ ​ ​ ​ ​ ​ ​

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	3 Months Ended
	Mar. 31, 2022
Summary of Significant Accounting Policies
Unaudited Interim Financial Information	Unaudited Interim Financial Information The accompanying condensed consolidated financial statements and the accompanying notes as of March 31, 2022 and December 31, 2021 and for the three-month periods ended March 31, 2022 and 2021 are unaudited. The condensed consolidated interim financial statements have been prepared on the same basis as the audited annual consolidated financial statements and, in the opinion of management, reflect all adjustments, which include only normal recurring adjustments necessary for the fair presentation of the Company’s financial position as of March 31, 2022 and the results of its operations for the three-month periods ended March 31, 2022 and 2021 and its cash flows for the three months ended March 31, 2022 and 2021.
Use of Estimates	Use of Estimates The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of expenses during the reporting periods. Estimates and judgments are based on historical information and other market-specific or various relevant assumptions, including in certain circumstances, future projections, that management believes to be reasonable under the circumstances. Actual results could differ materially from estimates. Significant estimates and assumptions are used for, but not limited to, the accruals for research and development expenses, the incremental borrowing rate for determining the operating lease right-of-use (“ROU”) asset and lease liabilities, and for periods prior to the completion of the IPO, the determination of fair value of equity instruments, and the fair value of the preferred stock tranche rights and the anti-dilution right, and stock-based compensation expense.
Fair Value of Financial Instruments	Fair Value of Financial Instruments The Company categorizes its assets and liabilities measured at fair value in accordance with ASC Topic 820, Fair Value Measurement determined based on assumptions that market participants would use in pricing an asset or liability. As a basis for considering such assumptions, ASC 820 establishes a three-tier fair value hierarchy, which prioritizes the inputs used in measuring fair value as follows: ● Level 1—Unadjusted quoted prices in active markets that are accessible at the measurement date for identical assets or liabilities; ● Level 2—Quoted prices for similar assets and liabilities in active markets, quoted prices in markets that are not active, or inputs which are observable, either directly or indirectly, for substantially the full term of the asset or liability; or ● Level 3—Prices or valuation techniques that require inputs that are both significant to the fair value measurement and unobservable (i.e., supported by little or no market activity).
Investments	Investments All investments have been classified as “available-for-sale” and are carried at fair value as determined based upon quoted market prices or pricing models for similar securities at period end. Investments with contractual maturities less than 12 months at the balance sheet date are considered short-term investments. Those investments with contractual maturities 12 months or greater at the balance sheet date are considered long-term investments. Dividend and interest income are recognized in the Company’s condensed consolidated statements of operations and comprehensive loss when earned. Realized gains and losses are included in earnings and are derived using the specific identification method for determining the cost of securities sold. Unrealized gains and losses are reported as a component of accumulated other comprehensive income (loss). The cost of the Company’s available-for-sale debt securities is adjusted for amortization of premium and accretion of discounts to maturity. The Company reviews its portfolio of available-for-sale debt securities, using both quantitative and qualitative factors, to determine if declines in fair value below cost have resulted from a credit-related loss or other factors. If the decline in fair value is due to credit-related factors, a loss is recognized in statements of operations, whereas if the decline in fair value is not due to credit-related factors, the loss is recorded in other comprehensive income (loss).
Leases	Leases Prior to January 1, 2021, the Company accounted for leases in accordance with FASB Accounting Standards Codification (“ASC”) ASC 840, Leases Effective on January 1, 2021, the Company accounts for leases in accordance with ASC Topic 842, Leases (“ASC 842”). In accordance with ASC 842, the Company determines whether an arrangement is or contains a lease at inception. A contract is or contains a lease if the contract conveys the right to control the use of an identified asset for a period of time in exchange for consideration. The Company classifies leases at the lease commencement date, when control of the underlying asset is transferred from the lessor to the Company, as operating or finance leases and records a ROU asset and a lease liability on the consolidated balance sheet for all real-estate leases with an initial lease term of greater than 12 months. Leases with a lease term of 12 months or less are not recorded on the balance sheet, but payments are recognized as expense on a straight-line basis over the lease term. A lease qualifies as a finance lease if any of the following criteria are met at the inception of the lease: (i) there is a transfer of ownership of the leased asset to the Company by the end of the lease term, (ii) the Company holds an option to purchase the leased asset that it is reasonably certain to exercise, (iii) the lease term is for a major part of the remaining economic life of the leased asset, (iv) the present value of the sum of lease payments equals or exceeds substantially all of the fair value of the leased asset, or (v) the nature of the leased asset is specialized to the point that it is expected to provide the lessor no alternative use at the end of the lease term. All other leases are recorded as operating leases. The Company enters into contracts that contain both lease and non-lease components. Non-lease components may include maintenance, utilities, and other operating costs. For all real estate asset classes, the Company combines the lease and non-lease components of fixed costs in its lease arrangements as a single lease component. Variable costs, such as utilities or maintenance costs, are not included in the measurement of ROU assets and lease liabilities, but rather are expensed when the event determining the amount of variable consideration to be paid occurs. Finance and operating lease assets and liabilities are recognized at the lease commencement date based on the present value of the lease payments over the lease term using the discount rate implicit in the lease. If the rate implicit is not readily determinable, the Company utilizes an estimate of its incremental borrowing rate based upon the available information at the lease commencement date. ROU assets are further adjusted for initial direct costs, prepaid rent, or incentives received. Operating lease payments are expensed using the straight-line method as an operating expense over the lease term. The Company’s lease terms may include options to extend or terminate the lease when it is reasonably certain that the Company will exercise that option. Finance lease assets are amortized to depreciation expense using the straight-line method over the shorter of the useful life of the related asset or the lease term. Finance lease payments are bifurcated into (i) a portion that is recorded as interest expense and (ii) a portion that reduces the finance liability associated with the lease.
Comprehensive Loss	Comprehensive Loss Comprehensive loss includes net loss as well as other changes in stockholders’ equity (deficit) that result from transactions and economic events other than those with stockholders, including unrealized gains and losses on investments. The unrealized losses on investments represent the only component of other comprehensive loss that is excluded from the reported net loss.
Recently Issued and Adopted Accounting Pronouncements	Recently Issued and Adopted Accounting Pronouncements From time to time, new accounting pronouncements are issued by the FASB or other standard setting bodies and adopted by the Company as of the specified effective date. Unless otherwise discussed, the Company believes that the impact of recently issued standards that are not yet effective will not have a material impact on its condensed consolidated financial statements and disclosures. The recently issued and adopted accounting pronouncements pertaining to the Company are disclosed in the Company’s audited consolidated financial statements for the year ended December 31, 2021, which were included in the Company’s Annual Report. Since the date of those financial statements, there have been no changes.

Fair Value of Financial Asset_2

Fair Value of Financial Assets and Liabilities (Tables)	3 Months Ended
	Mar. 31, 2022
Fair Value of Financial Assets and Liabilities
Schedule of assets and liabilities measured at fair value on a recurring basis	A ssets measured at fair value on a recurring basis as of March 31, 2022 are as follows (in thousands): ​

Investments (Tables)

Investments (Tables)	3 Months Ended
	Mar. 31, 2022
Investments
Schedule of investments classified as available-for-sale investments	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ MARCH 31, 2022 ​ MATURITY ​ AMORTIZED ​ UNREALIZED ​ UNREALIZED ​ FAIR ​ IN YEARS COST GAIN LOSS VALUE Commercial paper less than 1 ​ $ 25,344 ​ $ — ​ $ — ​ $ 25,344 Corporate debt securities less than 1 ​ ​ 36,550 ​ ​ — ​ ​ (70) ​ ​ 36,480 Asset-backed securities less than 1 ​ ​ 2,005 ​ ​ — ​ ​ (8) ​ ​ 1,997 Government securities less than 1 ​ ​ 21,945 ​ ​ 2 ​ ​ (11) ​ ​ 21,936 Short-term investments ​ ​ $ 85,844 ​ $ 2 ​ $ (89) ​ $ 85,757 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Corporate debt securities 1 - 2 ​ ​ 4,987 ​ ​ — ​ ​ (42) ​ ​ 4,945 Long-term investments ​ ​ $ 4,987 ​ $ — ​ $ (42) ​ $ 4,945 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

Property and Equipment, net (Ta

Property and Equipment, net (Tables)	3 Months Ended
	Mar. 31, 2022
Property and Equipment, net
Schedule of property and equipment, net	Property and equipment, net consisted of the following as of March 31, 2022 and as of December 31, 2021 (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ MARCH 31, DECEMBER 31, ​ ​ 2022 ​ 2021 Computer equipment ​ $ 39 ​ $ 12 Less: accumulated depreciation ​ (2) ​ (1) Property and equipment, net ​ $ 37 ​ $ 11 ​ ​ ​ ​ ​ ​ ​

Leases (Tables)

Leases (Tables)	3 Months Ended
	Mar. 31, 2022
Leases
Schedule of future minimum payments required under the lease	​ ​ ​ ​ ​ ​ ​ ​ ​ Remainder of 2022 ​ $ 1,024 2023 ​ ​ 774 2024 ​ ​ 797 2025 ​ ​ 821 2026 ​ ​ 846 Thereafter ​ ​ 1,995 Total future minimum lease payments ​ ​ 6,257 Less: imputed interest ​ ​ (1,536) Present value of lease liabilities ​ $ 4,721 ​ ​ ​ ​

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	3 Months Ended
	Mar. 31, 2022
Stock-Based Compensation
Schedule of stock option valuation assumptions	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ FOR THE THREE MONTHS ENDED FOR THE YEAR ENDED ​ ​ MARCH 31, 2022 ​ DECEMBER 31, 2021 Risk-free interest rate 1.60% - 2.16% ​ 1.07% Expected term (in years) 6.1 ​ 5.2 - 6.1 Expected volatility 78.00% - 78.90% ​ 75.58% - 83.56% Expected dividend yield 0.00% ​ 0.00% ​ ​ ​ ​ ​
Schedule of summary of option activity	A summary of option activity under the 2021 Plan during the three months ended March 31, 2022 is as follows (in thousands except share, per share data and contractual terms): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ WEIGHTED-AVERAGE WEIGHTED-AVERAGE ​ ​ ​ ​ ​ PER-SHARE ​ REMAINING ​ AGGREGATE ​ ​ SHARES ​ EXERCISE PRICE ​ CONTRACTUAL TERM ​ INTRINSIC VALUE Outstanding as of December 31, 2021 ​ 5,163,643 ​ $ 4.31 9.29 ​ $ 44,463 Granted ​ 1,657,200 ​ 11.22 ​ Outstanding as of March 31, 2022 ​ 6,820,843 ​ $ 5.99 9.25 ​ 39,468 Options vested and exercisable as of March 31, 2022 ​ 844,039 ​ $ 1.43 8.83 ​ $ 8,566 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​
Schedule of restricted stock activity	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ WEIGHTED-AVERAGE ​ ​ ​ ​ PER-SHARE GRANT-DATE ​ ​ SHARES ​ FAIR VALUE Unvested shares at December 31, 2021 830,046 ​ $ 2.85 Vested (85,431) ​ 0.83 Unvested shares at March 31, 2022 744,615 ​ $ 3.08 ​ ​ ​ ​ ​ ​
Schedule of stock-based compensation expense	Total stock-based compensation expense recorded as research and development and general and administrative expenses, respectively, for employees, directors and non-employees during the three months ended March 31, 2022 and 2021 was as follows (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ THREE MONTHS ENDED MARCH 31, ​ 2022 2021 Research and development ​ $ 1,008 ​ $ 439 General and administrative ​ ​ 1,036 ​ ​ 109 ​ ​ $ 2,044 ​ $ 548 ​ ​ ​ ​ ​ ​ ​

Net Loss Per Share (Tables)

Net Loss Per Share (Tables)	3 Months Ended
	Mar. 31, 2022
Net Loss Per Share
Schedule of basic and diluted loss per share	Basic and diluted loss per share is computed by dividing net loss attributable to common stockholders by the weighted-average common shares outstanding (in thousands, except share and per share data): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ THREE MONTHS ENDED MARCH 31, ​ 2022 2021 Numerator: ​ ​ ​ ​ ​ ​ Net loss ​ $ (10,497) ​ $ (4,473) Net loss attributable to common stockholders - basic and diluted ​ $ (10,497) ​ $ (4,473) Denominator: ​ ​ ​ ​ Weighted-average common stock outstanding - basic and diluted ​ 38,247,970 ​ 912,222 Net loss per share attributable to common stockholders - basic and diluted ​ $ (0.27) ​ $ (4.90) ​ ​ ​ ​ ​ ​ ​
Schedule of antidilutive securities excluded from computation of diluted net loss per share	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ THREE MONTHS ENDED MARCH 31, ​ ​ 2022 2021 Preferred Stock ​ — ​ 25,475,905 ​ Unvested restricted stock 744,615 740,406 Unvested RSUs ​ 35,900 ​ — ​ Options to purchase common stock ​ 6,820,843 ​ 2,034,953 ​ ​ 7,601,358 28,251,264 ​ ​ ​ ​ ​ ​

Nature of the Business (Details

Nature of the Business (Details) $ / shares in Units, $ in Thousands	Oct. 25, 2021USD ($)$ / sharesshares	Oct. 12, 2021$ / sharesshares	Sep. 27, 2021	Mar. 31, 2022USD ($)shares	Jun. 30, 2021USD ($)	Mar. 31, 2021USD ($)	Dec. 31, 2021USD ($)shares
Reverse split			1.32286
Common stock, shares authorized | shares		500,000,000		500,000,000			500,000,000
Redeemable convertible preferred stock, shares authorized | shares		50,000,000
Stock-based compensation				$ 2,044		$ 548
Accumulated deficit				(72,075)			$ (61,578)
Net loss				(10,497)		(4,473)
Net cash used in operations				(7,684)		(5,200)
Cash and cash equivalents				146,281		103,149	$ 244,662
Amount of cash and cash equivalents, and investments				$ 237,000
Previously reported
Stock-based compensation					$ (1,440)	44
Adjustment
Stock-based compensation					$ (936)	$ 548
IPO
Shares issued | shares		10,000,200
Share price per share | $ / shares		$ 16
Aggregate net offering proceeds	$ 162,500
Shares converted to common stock | shares		25,475,905
Over-Allotment Option
Share price per share | $ / shares	$ 16
Number of shares | shares	1,171,990

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Details) - USD ($)	3 Months Ended	12 Months Ended
	Mar. 31, 2022	Dec. 31, 2021
Property, Plant and Equipment [Line Items]
Impairments	$ 0
2021 Plan
Property, Plant and Equipment [Line Items]
Options to purchase common stock, exercised	0	345,930
Proceeds from early exercise of options		$ 1,400,000

Fair Value of Financial Asset_3

Fair Value of Financial Assets and Liabilities - Recurring basis (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Assets
Liabilities measured at fair value		$ 0
Transfer of assets from level 1 to level 2	$ 0	0
Transfer of assets from level 2 to level 1	0	0
Transfer of liabilities from level 1 to level 2	0	0
Transfer of liabilities from level 2 to level 1	0	$ 0
Recurring
Assets
Total financial assets	119,951
Recurring | Commercial Paper
Assets
Total financial assets	25,344
Recurring | Corporate Debt Securities
Assets
Total financial assets	41,425
Recurring | Asset-backed Securities
Assets
Total financial assets	1,997
Recurring | Government Securities
Assets
Total financial assets	21,936
Recurring | Money Market Funds
Assets
Total financial assets	29,249
Recurring | Level 1
Assets
Total financial assets	29,249
Recurring | Level 1 | Money Market Funds
Assets
Total financial assets	29,249
Recurring | Level 2
Assets
Total financial assets	90,702
Recurring | Level 2 | Commercial Paper
Assets
Total financial assets	25,344
Recurring | Level 2 | Corporate Debt Securities
Assets
Total financial assets	41,425
Recurring | Level 2 | Asset-backed Securities
Assets
Total financial assets	1,997
Recurring | Level 2 | Government Securities
Assets
Total financial assets	$ 21,936

Investments (Details)

Investments (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2022USD ($)
Investments
Short-term investments	$ 85,757
Long-term investments	4,945
Amount of fair value investments due to credit-related factors	0
Short-Term Investments
Investments
Amortized cost	85,844
Unrealized gain	2
Unrealized loss	(89)
Short-term investments	85,757
Commercial Paper | Short-Term Investments
Investments
Amortized cost	25,344
Short-term investments	25,344
Corporate Debt Securities | Short-Term Investments
Investments
Amortized cost	36,550
Unrealized loss	(70)
Short-term investments	36,480
Corporate Debt Securities | Long-Term Investments
Investments
Amortized cost	4,987
Unrealized loss	(42)
Long-term investments	4,945
Asset-backed Securities | Short-Term Investments
Investments
Amortized cost	2,005
Unrealized loss	(8)
Short-term investments	1,997
Government Securities | Short-Term Investments
Investments
Amortized cost	21,945
Unrealized gain	2
Unrealized loss	(11)
Short-term investments	$ 21,936

Property and Equipment, net (De

Property and Equipment, net (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Property and Equipment, net
Less: accumulated depreciation	$ (2)	$ (1)
Property and equipment, net	37	11
Computer equipment
Property and Equipment, net
Computer equipment	$ 39	$ 12

Property and Equipment, net - A

Property and Equipment, net - Additional Information (Details) - USD ($)	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Property and Equipment, net
Depreciation expense	$ 1,000	$ 1,000
Impairments recorded to date	$ 0

License Agreement (Details)

License Agreement (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
License Agreement
Cost of license included in research and development expense	$ 6,548	$ 3,825

Leases - Additional Information

Leases - Additional Information (Details) $ in Thousands	Sep. 16, 2021USD ($)ft²	Mar. 31, 2022USD ($)
Leases
Short-term lease cost		$ 100
Office space leased | ft²	7,351
Lease term	7 years
ROU Asset	$ 4,700	4,721
Operating lease liability	$ 4,700	$ 4,721
Renewal term	5 years
Initial base rent	$ 800
Lease subject to annual increase (as percentage)	3.00%
Security deposit in the form of line of credit	$ 400
weighted-average remaining lease term		7 years
Weighted-average discount rate		9.10%

Leases - Future minimum payment

Leases - Future minimum payments (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Sep. 16, 2021
Leases
Remainder of 2022	$ 1,024
2023	774
2024	797
2025	821
2026	846
Thereafter	1,995
Total future minimum lease payments	6,257
Less: imputed interest	(1,536)
Present value of lease liabilities	$ 4,721	$ 4,700

Commitments and Contingencies (

Commitments and Contingencies (Details) $ in Millions	Sep. 16, 2021USD ($)ft²	Mar. 31, 2022USD ($)	Dec. 31, 2021USD ($)
Commitments and Contingencies
Office space leased | ft²	7,351
Lease term	7 years
Renewal term	5 years
Initial base rent	$ 0.8
Lease subject to annual increase (as percentage)	3.00%
Security deposit in the form of line of credit	$ 0.4
401(k) Plan
Commitments and Contingencies
Amount employer contributions made to the 401(k) Plan		$ 0.1	$ 0

Stockholders Equity (Details)

Stockholders Equity (Details)	3 Months Ended
	Mar. 31, 2022USD ($)Vote$ / sharesshares	Dec. 31, 2021$ / sharesshares	Oct. 12, 2021shares
Preferred stock, par value | $ / shares	$ 0.0001	$ 0.0001
Preferred stock, shares authorized | shares	50,000,000	50,000,000
Common stock, authorized | shares	500,000,000	500,000,000	500,000,000
Common stock, par value | $ / shares	$ 0.0001	$ 0.0001
Number of votes per common stock | Vote	1
Common stock, cash dividend | $	$ 0

Stockholders Equity - Reserve f

Stockholders Equity - Reserve for future issuance (Details)	Mar. 31, 2022shares
Stockholders' Equity
Unvested restricted stock	35,900

Stock-Based Compensation (Detai

Stock-Based Compensation (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2022	Dec. 31, 2021
Stock-Based Compensation
Expiration period	10 years
2021 Plan
Stock-Based Compensation
Shares reserved under the Plan	9,094,083	9,094,083
Shares available for future grant under the Plan	2,237,340	3,930,440
Vesting period	4 years
Options to purchase common stock, exercised	0	345,930
Proceeds from options exercised		$ 1.4
2021 Plan | Restricted stock
Stock-Based Compensation
Vesting period	5 years
2021 ESPP
Stock-Based Compensation
Shares reserved under the Plan	400,000

Stock-Based Compensation - Stoc

Stock-Based Compensation - Stock Option Valuation (Details)	3 Months Ended	12 Months Ended
	Mar. 31, 2022	Dec. 31, 2021
Stock-Based Compensation
Risk-free interest rate		1.07%
Expected volatility, Minimum	78.00%	75.58%
Expected volatility, Maximum	78.90%	83.56%
Expected dividend yield	0.00%	0.00%
Minimum
Stock-Based Compensation
Expected term (in years)	6 years 1 month 6 days	5 years 2 months 12 days
Maximum
Stock-Based Compensation
Expected term (in years)		6 years 1 month 6 days

Stock-Based Compensation - Summ

Stock-Based Compensation - Summary of option activity (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Additional Disclosures
Weighted-average per share grant date fair value of options granted		$ 5.46
Recognition period	2 years
Restricted stock
Additional Disclosures
Unrecognized stock-based compensation expense related to unvested stock options	$ 400
Recognition period	3 years 10 months 24 days
Options to purchase common stock
Shares
Outstanding as of beginning of period (in shares)	5,163,643
Granted (in shares)	1,657,200
Outstanding as of end of period (in shares)	6,820,843		5,163,643
Options vested and exercisable (in shares)	844,039
Weighted-average per-share exercise price
Outstanding as of beginning of period (in per share)	$ 4.31
Granted (in per share)	11.22
Outstanding as of end of period (in per share)	5.99		$ 4.31
Options vested and exercisable (in per share)	$ 1.43
Additional Disclosures
Weighted-average remaining contractual term	9 years 3 months		9 years 3 months 14 days
Weighted-average remaining contractual term, vested and exercisable	8 years 9 months 29 days
Aggregate intrinsic value	$ 39,468		$ 44,463
Aggregate intrinsic value, vested and exercisable	$ 8,566
Weighted-average per share grant date fair value of options granted	$ 7.68
Unrecognized stock-based compensation expense related to unvested stock options	$ 31,500
Recognition period	3 years 1 month 6 days

Stock-Based Compensation - Shar

Stock-Based Compensation - Shares of Restricted Common Stock (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Shares
Granted (in shares)	35,900
Unvested shares, Ending balance (in shares)	35,900
Weighted-average per-share grant-date fair value
Granted (in per shares)	$ 11.21
Unvested shares, Ending balance (in per share)	$ 11.21
Recognition period	2 years
Stock-based compensation expense	$ 2,044	$ 548
Restricted stock
Shares
Unvested shares, Beginning balance (in shares)	830,046
Vested	(85,431)
Unvested shares, Ending balance (in shares)	744,615
Weighted-average per-share grant-date fair value
Unvested shares, Beginning balance (in per share)	$ 2.85
Vested	0.83
Unvested shares, Ending balance (in per share)	$ 3.08
Unrecognized stock-based compensation expense related to unvested restricted stock	$ 2,300
Recognition period	3 years 10 months 24 days

Stock-Based Compensation - Expe

Stock-Based Compensation - Expense (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Stock-Based Compensation
Stock-based compensation expense	$ 2,044	$ 548
Research and development
Stock-Based Compensation
Stock-based compensation expense	1,008	439
General and administrative
Stock-Based Compensation
Stock-based compensation expense	$ 1,036	$ 109

Income Taxes - Additional infor

Income Taxes - Additional information (Details) - USD ($)	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Income Taxes
Income tax	$ 0	$ 0

Net Loss Per Share - Basic and

Net Loss Per Share - Basic and diluted loss per share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Numerator:
Net loss	$ (10,497)	$ (4,473)
Net loss attributable to common stockholders - basic	(10,497)	(4,473)
Net loss attributable to common stockholders - diluted	$ (10,497)	$ (4,473)
Denominator:
Weighted-average common stock outstanding-basic	38,247,970	912,222
Weighted-average common stock outstanding- diluted	38,247,970	912,222
Net loss per share attributable to common stockholders-basic	$ (0.27)	$ (4.90)
Net loss per share attributable to common stockholders- diluted	$ (0.27)	$ (4.90)

Net Loss Per Share - Antidiluti

Net Loss Per Share - Antidilutive securities (Details) - shares	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Anti-dilutive Effect
Shares excluded since there inclusion would be anti-dilutive	7,601,358	28,251,264
Preferred Stock
Anti-dilutive Effect
Shares excluded since there inclusion would be anti-dilutive		25,475,905
Restricted stock
Anti-dilutive Effect
Shares excluded since there inclusion would be anti-dilutive	744,615	740,406
Unvested RSUs
Anti-dilutive Effect
Shares excluded since there inclusion would be anti-dilutive	35,900
Options to purchase common stock
Anti-dilutive Effect
Shares excluded since there inclusion would be anti-dilutive	6,820,843	2,034,953

Commitments and Contingencies -

Commitments and Contingencies - Future minimum payments (Details) $ in Thousands	Mar. 31, 2022USD ($)
Commitments and Contingencies.
Remainder of 2022	$ 1,024
2023	774
2024	797
2025	821
2026	846
Total future minimum lease payments	$ 6,257