0000950170-21-004476 | 10-Q | XBRL Viewer

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Document and Entity Information - shares	9 Months Ended
Document and Entity Information - shares	Sep. 30, 2021	Nov. 12, 2021
Cover [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Sep. 30, 2021
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	Q3
Document Transition Report	false
Document Quarterly Report	true
Entity Registrant Name	Pyxis Oncology, Inc.
Entity Central Index Key	0001782223
Current Fiscal Year End Date	--12-31
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 Current Reporting Status	No
Entity Interactive Data Current	Yes
Entity File Number	001-40881
Entity Tax Identification Number	83-1160910
Entity Address, Address Line One	35 Cambridge Park Drive
Entity Address, City or Town	Cambridge
Entity Address, State or Province	MA
Entity Address, Postal Zip Code	02140
Entity Incorporation, State or Country Code	DE
City Area Code	617
Local Phone Number	221-9059
Title of 12(b) Security	Common Stock, par value $0.001 per share
Trading Symbol	PYXS
Security Exchange Name	NASDAQ
Entity Common Stock, Shares Outstanding		32,763,887

Condensed Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Current assets:
Cash and cash equivalents	$ 133,477	$ 8,080
Prepaid expenses and other current assets	859	23
Total current assets	134,336	8,103
Property and equipment, net	1,154	1,103
Operating lease right-of-use assets	388	836
Deferred offering costs	3,501
Other assets, noncurrent	109	109
Total assets	139,488	10,151
Current liabilities:
Accounts payable	1,927	1,077
Accrued expenses and other current liabilities	5,462	1,997
Derivative liability, current portion	9,123
Operating lease liabilities, current portion	325	615
Total current liabilities	16,837	3,689
Derivative liability, net of current portion	67
Operating lease liabilities, net of current portion		165
Total liabilities	16,904	3,854
Commitments and contingencies (Note 12)
Stockholders’ deficit:
Common stock, $0.001 par value per share; 167,000,000 and 40,300,000 shares authorized at September 30, 2021 and December 31, 2020, respectively; 2,194,326 and 2,177,956 shares issued at September 30, 2021 and December 31, 2020 and 1,639,600 and 1,289,342 shares outstanding at September 30, 2021 and December 31, 2020, respectively	2	1
Additional paid-in capital	3,448	97
Accumulated deficit	(74,889)	(15,743)
Total stockholders’ deficit	(71,439)	(15,645)
Total liabilities, convertible preferred stock and stockholders’ deficit	139,488	10,151
Series A Convertible Preferred Stock
Current liabilities:
Convertible Preferred Stock	21,942	$ 21,942
Series B Convertible Preferred Stock
Current liabilities:
Convertible Preferred Stock	$ 172,081

Condensed Consolidated Balance Sheets (Parenthetical) (Unaudited) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Common stock, par value per share	$ 0.001	$ 0.001
Common stock, shares authorized	167,000,000	40,300,000
Common stock, shares issued	2,194,326	2,177,956
Common stock, shares outstanding	1,639,600	1,289,342
Series A Convertible Preferred Stock
Convertible preferred stock, par value per share	$ 0.001	$ 0.001
Convertible preferred stock, shares authorized	22,724,926	22,724,926
Convertible preferred stock, shares issued	22,724,925	22,724,925
Convertible preferred stock, shares outstanding	22,724,925	22,724,925
Convertible preferred stock, liquidation value	$ 22,000	$ 22,000
Series B Convertible Preferred Stock
Convertible preferred stock, par value per share	$ 0.001
Convertible preferred stock, shares authorized	104,812,248	0
Convertible preferred stock, shares issued	104,812,248	0
Convertible preferred stock, shares outstanding	104,812,248	0
Convertible preferred stock, liquidation value	$ 172,500

Condensed Consolidated Statements of Operations and Comprehensive Loss (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Operating expenses:
Research and development expense	$ 7,849	$ 2,425	$ 43,828	$ 5,909
General and administrative	3,772	767	9,463	2,406
Total operating expenses	11,621	3,192	53,291	8,315
Loss from operations	(11,621)	(3,192)	(53,291)	(8,315)
Other income (expense):
Interest income	6	1	16	66
Service fee income from related party			181
Change in fair value of derivative liability	(2,560)		(5,821)
Total other income (expense)	(2,554)	1	(5,624)	66
Loss from equity method investment in joint venture			(231)
Net loss and comprehensive loss	$ (14,175)	$ (3,191)	$ (59,146)	$ (8,249)
Net loss per common share, basic and diluted	$ (8.96)	$ (2.93)	$ (40.27)	$ (8.43)
Weighted average common shares outstanding, basic and diluted	1,581,610	1,088,222	1,468,777	979,081

Condensed Consolidated Statements of Convertible Preferred Stock and Stockholders' Equity Deficit - USD ($) $ in Thousands	Total	Series A Convertible Preferred Stock	Series B Convertible Preferred Stock	Common Stock	Additional paid-in capital	Accumulated deficit
Beginning balance at Dec. 31, 2019		$ 21,942
Beginning Balance, Shares at Dec. 31, 2019		22,724,925
Beginning balance at Dec. 31, 2019	$ (2,874)			$ 1	$ 40	$ (2,915)
Beginning Balance, Shares at Dec. 31, 2019				828,356
Vesting of restricted common stock	1				1
Vesting of restricted common stock ( Shares)				76,933
Stock-based compensation	9				9
Net loss	(1,958)					(1,958)
Ending balance at Mar. 31, 2020		$ 21,942
Ending balance (in shares) at Mar. 31, 2020		22,724,925
Ending balance at Mar. 31, 2020	(4,822)			$ 1	50	(4,873)
Ending balance (in shares) at Mar. 31, 2020				905,289
Beginning balance at Dec. 31, 2019		$ 21,942
Beginning Balance, Shares at Dec. 31, 2019		22,724,925
Beginning balance at Dec. 31, 2019	(2,874)			$ 1	40	(2,915)
Beginning Balance, Shares at Dec. 31, 2019				828,356
Net loss	(8,249)
Ending balance at Sep. 30, 2020		$ 21,942
Ending balance (in shares) at Sep. 30, 2020		22,724,925
Ending balance at Sep. 30, 2020	(11,087)			$ 1	76	(11,164)
Ending balance (in shares) at Sep. 30, 2020				1,133,301
Beginning balance at Dec. 31, 2019		$ 21,942
Beginning Balance, Shares at Dec. 31, 2019		22,724,925
Beginning balance at Dec. 31, 2019	(2,874)			$ 1	40	(2,915)
Beginning Balance, Shares at Dec. 31, 2019				828,356
Ending balance at Dec. 31, 2020		$ 21,942
Ending balance (in shares) at Dec. 31, 2020		22,724,925
Ending balance at Dec. 31, 2020	(15,645)			$ 1	97	(15,743)
Ending balance (in shares) at Dec. 31, 2020				1,289,342
Beginning balance at Mar. 31, 2020		$ 21,942
Beginning Balance, Shares at Mar. 31, 2020		22,724,925
Beginning balance at Mar. 31, 2020	(4,822)			$ 1	50	(4,873)
Beginning Balance, Shares at Mar. 31, 2020				905,289
Vesting of restricted common stock	1				1
Vesting of restricted common stock ( Shares)				76,933
Stock-based compensation	9				9
Issuance of common stock	2				2
Issuance of common stock (Shares)				48,919
Net loss	(3,100)					(3,100)
Ending balance at Jun. 30, 2020		$ 21,942
Ending balance (in shares) at Jun. 30, 2020		22,724,925
Ending balance at Jun. 30, 2020	(7,910)			$ 1	62	(7,973)
Ending balance (in shares) at Jun. 30, 2020				1,031,141
Vesting of restricted common stock	3				3
Vesting of restricted common stock ( Shares)				102,160
Stock-based compensation	11				11
Net loss	(3,191)					(3,191)
Ending balance at Sep. 30, 2020		$ 21,942
Ending balance (in shares) at Sep. 30, 2020		22,724,925
Ending balance at Sep. 30, 2020	(11,087)			$ 1	76	(11,164)
Ending balance (in shares) at Sep. 30, 2020				1,133,301
Beginning balance at Dec. 31, 2020		$ 21,942
Beginning Balance, Shares at Dec. 31, 2020		22,724,925
Beginning balance at Dec. 31, 2020	(15,645)			$ 1	97	(15,743)
Beginning Balance, Shares at Dec. 31, 2020				1,289,342
Issuance of Series B convertible preferred stock, net of issuance costs of $419			$ 172,081
Issuance of Series B convertible preferred stock, net of issuance costs of $419, Shares			104,812,248
Vesting of restricted common stock	3				3
Vesting of restricted common stock ( Shares)				123,085
Stock-based compensation	2,450				2,450
Net loss	(36,968)					(36,968)
Ending balance at Mar. 31, 2021		$ 21,942	$ 172,081
Ending balance (in shares) at Mar. 31, 2021		22,724,925	104,812,248
Ending balance at Mar. 31, 2021	(50,160)			$ 1	2,550	(52,711)
Ending balance (in shares) at Mar. 31, 2021				1,412,427
Beginning balance at Dec. 31, 2020		$ 21,942
Beginning Balance, Shares at Dec. 31, 2020		22,724,925
Beginning balance at Dec. 31, 2020	$ (15,645)			$ 1	97	(15,743)
Beginning Balance, Shares at Dec. 31, 2020				1,289,342
Stock options exercised (Shares)	16,370
Net loss	$ (59,146)
Ending balance at Sep. 30, 2021		$ 21,942	$ 172,081
Ending balance (in shares) at Sep. 30, 2021		22,724,925	104,812,248
Ending balance at Sep. 30, 2021	(71,439)			$ 2	3,448	(74,889)
Ending balance (in shares) at Sep. 30, 2021				1,639,600
Beginning balance at Mar. 31, 2021		$ 21,942	$ 172,081
Beginning Balance, Shares at Mar. 31, 2021		22,724,925	104,812,248
Beginning balance at Mar. 31, 2021	(50,160)			$ 1	2,550	(52,711)
Beginning Balance, Shares at Mar. 31, 2021				1,412,427
Vesting of restricted common stock	3			$ 1	2
Vesting of restricted common stock ( Shares)				106,580
Stock-based compensation	572				572
Net loss	(8,003)					(8,003)
Ending balance at Jun. 30, 2021		$ 21,942	$ 172,081
Ending balance (in shares) at Jun. 30, 2021		22,724,925	104,812,248
Ending balance at Jun. 30, 2021	(57,588)			$ 2	3,124	(60,714)
Ending balance (in shares) at Jun. 30, 2021				1,519,007
Vesting of restricted common stock	3				3
Vesting of restricted common stock ( Shares)				104,223
Stock options exercised	14				14
Stock options exercised (Shares)				16,370
Stock-based compensation	307				307
Net loss	(14,175)					(14,175)
Ending balance at Sep. 30, 2021		$ 21,942	$ 172,081
Ending balance (in shares) at Sep. 30, 2021		22,724,925	104,812,248
Ending balance at Sep. 30, 2021	$ (71,439)			$ 2	$ 3,448	$ (74,889)
Ending balance (in shares) at Sep. 30, 2021				1,639,600

Condensed Consolidated Statements of Convertible Preferred Stock and Stockholders' Deficit (Parenthetical) $ in Thousands	3 Months Ended
	Mar. 31, 2021 USD ($)
Series B Convertible Preferred Stock
Issuance costs	$ 419

Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
Cash flows from operating activities
Net loss	$ (59,146)	$ (8,249)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	489	299
Stock-based compensation	3,329	29
Non-cash research and development expenses	20,000
Non-cash lease expense	448	289
Non-cash loss from equity method investment in joint venture	50
Change in fair value of derivative liability	5,821
Changes in operating assets and liabilities:
Prepaid and other current assets	(836)	(84)
Accounts payable	610	117
Accrued expenses and other current liabilities	3,164	960
Operating lease liabilities	(455)	(278)
Derivative liability	3,369
Net cash used in operating activities	(23,157)	(6,917)
Cash flows from investing activities
Purchase of property and equipment	(540)	(1,483)
Investment in joint venture	(50)
Net cash used in investing activities	(590)	(1,483)
Cash flows from financing activities
Proceeds from issuance of Series B Convertible Preferred Stock, net of issuance costs	151,581
Deferred offering costs	(2,451)
Proceeds from the issuance of common stock		3
Proceeds from the exercise of stock options	14	31
Net cash provided by financing activities	149,144	34
Net (decrease) increase in cash, cash equivalents, and restricted cash	125,397	(8,366)
Cash, cash equivalents and restricted cash at beginning of period	8,189	19,721
Cash, cash equivalents and restricted cash at end of period	133,586	11,355
Supplemental schedule of noncash operating and financing activities:
Deferred offering costs in accounts payable and accrued expenses	1,050
Operating lease right-of-use asset obtained in exchange for new operating lease liabilities		1,186
Reconciliation of cash, cash equivalents and restricted cash:
Cash and cash equivalents	133,477	11,246
Restricted cash	109	109
Cash, cash equivalents and restricted cash at end of period	$ 133,586	$ 11,355

Description of Business	9 Months Ended
Description of Business	Sep. 30, 2021
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Description of Business	1. Description of Business Nature of Business Pyxis Oncology, Inc. (the “Company”), a Delaware corporation, was founded in June 2018 and launched its operations in July 2019. The Company is a preclinical oncology company focused on developing an arsenal of next-generation therapeutics to target difficult-to-treat cancers and improve quality of life for patients. The Company develops its product candidates with the objective to directly kill tumor cells, and to address the underlying pathologies created by cancer that enable its uncontrollable proliferation and immune evasion. Since the Company’s launch in 2019, the Company has developed a broad portfolio of novel antibody drug conjugate, or ADC, product candidates and monoclonal antibody, or mAb, preclinical discovery programs that the Company is developing as monotherapies and in combination with other therapies.

Basis of Presentation and Summary of Significant Accounting Policies	9 Months Ended
	Sep. 30, 2021
Accounting Policies [Abstract]
Basis of Presentation and Summary of Significant Accounting Policies	2. Basis of Presentation and Summary of Significant Accounting Policies Basis of Presentation The Company’s fiscal year ends on December 31 and its first three fiscal quarters end on March 31, June 30 and September 30. The accompanying condensed consolidated financial statements are unaudited. The unaudited condensed consolidated financial statements of the Company have been prepared in accordance with generally accepted accounting principles in the United States (“U.S. GAAP”) and follow the requirements of the Securities and Exchange Commission (“SEC”) for interim financial reporting. Accordingly, they do not include all of the information and disclosures required by U.S. GAAP for complete financial statements as certain footnotes or other financial information that are normally required by U.S. GAAP can be condensed or omitted. The unaudited condensed consolidated financial statements have been prepared on the same basis as the audited consolidated financial statements. The unaudited condensed consolidated financial statements include the accounts of the Company and its wholly-owned subsidiary. The Company has no unconsolidated subsidiaries. All intercompany balances and transactions have been eliminated in consolidation. Any reference in these notes to applicable guidance is meant to refer to the authoritative U.S. GAAP as found in the Accounting Standards Codification (“ASC”) and Accounting Standards Updates (“ASU”) of the Financial Accounting Standards Board (“FASB”). In the opinion of management, the unaudited condensed consolidated financial statements include all normal and recurring adjustments that are considered necessary for the fair statement of results for the interim periods. The results for the three and nine months ended September 30, 2021 are not necessarily indicative of those expected for the year ending December 31, 2021 or for any future period. The condensed consolidated balance sheet as of December 31, 2020 included herein was derived from the audited consolidated financial statements as of that date. These unaudited condensed consolidated financial statements should be read in conjunction with the Company’s audited consolidated financial statements and the related notes thereto for the year ended December 31, 2020, included in the Company’s final prospectus filed with the SEC pursuant to Rule 424(b)(4) on October 8, 2021 (“Final Prospectus”). Initial Public Offering In October 2021, the Company completed its initial public offering (“IPO”), for the sale and issuance of 10,500,000 shares of its common stock at $16.00 per share. The Company received net proceeds of approximately $152.2 million, after deducting underwriters’ discounts and commissions and other issuance costs. Prior to the IPO, all deferred offering costs were capitalized in other noncurrent assets on the condensed consolidated balance sheets. Deferred offering costs of $3.5 million, primarily consisting of accounting, legal, and other fees related to the Company’s IPO, will be offset against the IPO proceeds upon the closing of the Company’s IPO in October 2021. As of September 30, 2021 unpaid deferred offering costs totaled $1.1 million. Reverse Stock Split On October 1, 2021, the Company’s board of directors approved and effected a 1-for-6.359 reverse stock split of its issued and outstanding common stock and stock option awards. All issued and outstanding shares of common stock, stock option awards and per share data have been adjusted in these unaudited condensed consolidated financial statements, on a retrospective basis, to reflect the reverse stock split for all periods presented. The par value of the common stock and preferred stock was not adjusted as a result of the reverse stock split. The shares of common stock underlying outstanding stock options and other equity instruments were proportionately reduced and the respective exercise prices, if applicable, were proportionately increased in accordance with the terms of the agreements governing such securities. In connection with the IPO, all 127,537,173 shares of convertible preferred stock automatically converted into 20,056,145 shares of common stock. Stockholders entitled to fractional shares as a result of the reverse stock split received a cash payment in lieu of receiving fractional shares. Liquidity As of September 30, 2021, the Company had an accumulated deficit of $74.9 million. The Company has incurred losses and negative cash flows from operations since inception, including net losses of $59.1 million and $8.2 million for the nine months ended September 30, 2021 and 2020, respectively. The Company has not generated any revenues to date and does not anticipate generating any revenues unless and until it successfully completes development and obtains regulatory approval for its current or any future product candidates. The Company expects that its operating losses and negative cash flows will continue for the foreseeable future as the Company continues to expand its research and development programs and develop its product candidates. In October 2021, the Company raised approximately $152.2 million in net proceeds in an IPO. The Company currently expects that its existing cash and cash equivalents of $133.5 million as of September 30, 2021 along with proceeds from IPO will be sufficient to fund its operating expenses and capital requirements at least twelve months from the date these unaudited condensed consolidated financial statements are issued. Additional funding may be necessary to fund future clinical and preclinical activities. The Company plans to continue to fund its losses from operations and capital funding needs through public or private equity, convertible or debt financings or other sources. If the Company is not able to secure adequate additional funding, the Company may be forced to make reductions in spending, extend payment terms with suppliers, liquidate assets where possible, or suspend or curtail planned programs. Any of these actions could materially harm the Company’s business, results of operations and future prospects. Use of Estimates The preparation of unaudited condensed consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the amounts reported in the unaudited condensed consolidated financial statements and accompanying notes. The Company regularly evaluates estimates and assumptions related to assets, liabilities, stock-based compensation, derivative liability, operating leases, and research and development costs. The Company bases its estimates and assumptions on historical experience and on various other factors that it believes to be reasonable under the circumstances, the results of which form the basis for making judgments about the carrying values of assets and liabilities that are not readily apparent from other sources. Actual results could differ from those estimates. Concentration of Credit Risks Financial instruments that subject the Company to significant concentrations of credit risk consist primarily of cash and cash equivalents. The Company’s cash and cash equivalents are held at an accredited financial institution and the Company has not experienced any losses in such accounts. The Company maintains its cash in bank deposit accounts, which at times may exceed federally insured limits. The Company’s cash equivalents consist primarily of short-term money market funds held in accredited financial institutions. The Company believes it is not exposed to any significant risk in cash and cash equivalents. Significant Accounting Policies There have been no changes to the Company’s significant accounting policies disclosed in “Note 2 – Summary of Significant Accounting Policies” of the Company’s Final Prospectus. Recent Accounting Pronouncements Recent authoritative guidance issued by the FASB (including technical corrections to the ASC), the American Institute of Certified Public Accountants, and the SEC did not, or are not expected to, have a material impact on the Company’s unaudited condensed consolidated financial statements and related disclosures.

Fair Value Measurements

9 Months Ended

Sep. 30, 2021

Fair Value Disclosures [Abstract]

Fair Value Measurements

3. Fair Value Measurements

The following tables present the financial instruments carried at fair value on a recurring basis as of September 30, 2021 and December 31, 2020, respectively, in accordance with the FASB ASC 820 hierarchy (in thousands):


	Fair Value Measurements at September 30, 2021
	Level 1		Level 2		Level 3		Total
Assets
Cash equivalents	$	128,447	$	—	$	—	$	128,447
Liabilities
Derivative liability	$	—	$	—	$	9,190	$	9,190


	Fair Value Measurements at December 31, 2020
	Level 1		Level 2		Level 3		Total
Assets
Cash equivalents	$	6,996	$	—	$	—	$	6,996

The Company’s cash equivalents represent deposits in a short-term United States Treasury money market fund quoted in an active market and classified as a Level 1 asset. There were no assets or liabilities measured at fair value on a nonrecurring basis at September 30, 2021 and December 31, 2020. There were no transfers between Level 1 and Level 2 of the fair value hierarchy during the three and nine months ended September 30, 2021 and 2020.

The fair value of the derivative liability was initially determined using a probability-weighted income approach and is revalued at each reporting date or more frequently if circumstances dictate. Changes in the fair value of the derivative liability are recorded as income or expense within other income (expense) in the unaudited condensed consolidated statements of operations and comprehensive loss. The significant unobservable inputs used in the fair value measurement of the derivative liability include probability of payment factors and the discount rate. Significant increases or decreases in any of those inputs would result in a significantly lower or higher fair value measurement. As our operations progress, we may need to update the probability of payment factors and the discount rate used. This could result in a material increase or decrease to the derivative liability. Refer to Note 5, Licensing Agreements, for additional information on the derivative liability.

The following tables provide a summary of changes in our Level 3 fair value measurements for the three and nine months ended September 30, 2021:



	Three months ended		Nine months ended
	September 30, 2021
($ in thousands)
Derivative liability balance at the beginning of the period	$	6,630	$	—
Recognition of derivative liability		—		3,369
Change in fair value recorded in earnings		2,560		5,821
Balance as of September 30, 2021	$	9,190	$	9,190

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References + Details

Joint Venture

9 Months Ended

Sep. 30, 2021

Equity Method Investments And Joint Ventures [Abstract]

Joint Venture

4. Joint Venture

In March 2021, the Company entered into definitive transaction agreements with Alloy Therapeutics, Inc. (“Alloy”) and Voxall Therapeutics, LLC (“Voxall”), to finance and operate Voxall, a joint venture company formed in collaboration with Alloy to leverage the Company’s technology and Alloy’s ATX-Gx™ platform and antibody discovery services. Voxall granted to the Company and Alloy 50% of the voting membership units of Voxall in exchange for certain initial contributions. The Company’s initial contribution included $50 thousand and a non-exclusive fully paid-up license to certain intellectual property owned or controlled by the Company and the execution of the services agreement to enable the collaboration with Voxall. Alloy’s initial contribution included $50 thousand and the execution of the Alloy license agreement and the Alloy services agreement to enable the collaboration with Voxall. Voxall is governed by a board of directors consisting of an equal number of the Company’s representatives and Alloy’s representatives. The protective provisions under Voxall’s operating agreement require the approval of both the Company and Alloy before Voxall may take certain actions.

The Company accounted for investment in Voxall under the equity method of accounting. The initial contribution was recorded as “Investment in equity method investment in joint venture”. Additionally, the Company has recognized zero and $0.2 million in service fee income from a related party within other income for services provided to Voxall during the three and nine months ended September 30, 2021, respectively, for which Voxall issued a promissory note to the Company.

Voxall has incurred losses since inception and the Company’s share in the losses of Voxall aggregated to $0.1 million and $0.8 million for the three and nine months ended September 30, 2021, respectively. The Company recognized its share of losses of Voxall only to the extent of the carrying value of its investment in Voxall and the promissory note issued by Voxall, which aggregated to zero and $0.2 million for the three and nine months ended September 30, 2021, respectively. The remaining unabsorbed loss will be offset against future income, if any. As the Company has no commitment to fund the losses of the equity method investment, the carrying value of the equity method investment has not been reduced below zero.

Licensing Agreements

9 Months Ended

Sep. 30, 2021

License Agreements [Abstract]

Licensing Agreements

5. Licensing Agreements

The University of Chicago Agreement

In April 2020, the Company entered into a license agreement (the “University License Agreement”), as well as a sponsored research agreement, with the University of Chicago (the “University”). In partial consideration for the license from the University, the Company issued to the University 311,076 shares (48,919 shares post reverse stock split) of its Common Stock in 2020. The Company recorded the value of the shares issued of $3 thousand as research and development expenses during the nine months ended September 30, 2020. There have been zero expenses incurred for the three and nine months ended September 30, 2021 with regards to the University License Agreement.

The Company assessed the milestone and royalty events involving the University as of September 30, 2021 and concluded no such amounts were incurred.

Pfizer, Inc. Agreement

In December 2020, the Company entered into a license agreement (as amended, the “Pfizer License Agreement”) with Pfizer, Inc. (“Pfizer”). The Pfizer License Agreement became effective in March 2021. During the three and nine months ended September 30, 2021, the Company incurred costs of zero and $25.0 million, respectively, which was recorded as research and development expenses, consisting of an upfront fee equal to a cash payment of $5.0 million and the issuance of 12,152,145 shares of Series B Convertible Preferred Stock with a value of $20.0 million to Pfizer.

The Company assessed the milestone, royalty and other events involving Pfizer as of September 30, 2021 and concluded no such amounts were incurred.

LegoChem Biosciences, Inc. Agreements

In December 2020, the Company entered into a license agreement (the “LegoChem License Agreement”) and an opt-in, investment and additional consideration agreement (the “Opt-In Agreement”) with LegoChem Biosciences, Inc. (“LegoChem”). Pursuant to the LegoChem License Agreement, the Company paid $0.5 million in December 2020 and $9.0 million in March 2021 to LegoChem and is required to purchase certain initial quantities of licensed product from LegoChem for an estimated cost of $7.0 million. The Company recorded a $9.0 million payment for research and development expenses during the nine months ended September 30, 2021. The Company assessed the legal obligations related to the manufacturing of the initial quantities of licensed product as of September 30, 2021 and determined no such payments were required. The Company assessed the milestones and royalties under the LegoChem License Agreement as of September 30, 2021 and concluded no such amounts were incurred.

In addition, as part of the Opt-in Agreement, the Company recorded $0.5 million in accrued expenses in the consolidated balance sheet and related research and development expenses for such license fee in December 2020. The Company settled the outstanding liability of $0.5 million through the issuance of 303,804 shares of Series B Convertible Preferred Stock as part of its Series B financing in March 2021. LegoChem exercised its option in December 2020 under the Opt-In Agreement and paid $8.0 million to the Company in April 2021, in exchange for the right to receive a milestone payment (the “Extra Milestone Payment”) of $9.6 million upon the earliest to occur of certain events, including the date of pricing or offer of the first public offering of its common stock or if the Company is the subject of a change in control transaction. The Company determined that the Extra Milestone Payment meets the definition and recognition condition of derivative under ASC 815, “Derivatives and Hedging” for which there was a binding contract and firm commitment. An initial derivative liability was recognized for $3.4 million with an offset to research and development expenses in January 2021. The derivative liability is re-measured at each reporting date, with changes recorded in “Other income (expense)” in the condensed consolidated statements of operations and comprehensive loss. The Company recorded a fair value adjustment to the derivative liability of $2.6 million and $5.8 million for the three and nine months ended September 30, 2021. As of September 30, 2021, the derivative liability for the Extra Milestone Payment was $9.2 million. The Company assessed the other milestone and royalties under the Opt-In Agreement as of September 30, 2021 and concluded no such amounts were incurred.

Convertible Preferred Stock

9 Months Ended

Sep. 30, 2021

Temporary Equity Disclosure [Abstract]

Convertible Preferred Stock

6. Convertible Preferred Stock

Series A Convertible Preferred Stock

In June 2019, the Company entered into a securities purchase agreement (as amended, “Series A Agreement”) with certain investors to sell shares of Series A convertible preferred stock (“Series A”) at $0.9681 per share. In June and July 2019, the Company issued 22,724,925 shares of Series A to institutional investors at $0.9681 per share for gross cash proceeds of $22.0 million, less issuance costs of $0.1 million, resulting in net proceeds of $21.9 million. The Company effected a 1-for-6.359 reverse stock split in October 2021. Upon the initial public offering, 22,724,925 shares of Series A were converted to 3,573,659 shares of common stock.

Series B Convertible Preferred Stock

On March 5, 2021, the Company entered into a securities purchase agreement (as amended, “Series B Agreement”) with certain investors to sell shares of Series B convertible preferred stock (“Series B”) at $1.6458 per share. In March 2021, the Company issued 92,356,299 shares of Series B to institutional investors at $1.6458 per share for gross cash proceeds of $152.0 million, less issuance costs of $0.4 million, resulting in net proceeds of $151.6 million. In addition, the Company granted 12,455,949 shares, or $20.5 million, of Series B convertible preferred stock through separate agreements with Pfizer, Inc. and LegoChem Biosciences Inc. The Company effected a 1-for-6.359 reverse stock split in October 2021. Upon the initial public offering, 104,812,248 shares of Series B were converted to 16,482,486 shares of common stock.

Rights, Preferences, Privileges and Restrictions

Voting—Each preferred stockholder is entitled to cast the number of votes equal to the number of whole shares of common stock into which the shares of preferred stock held by such holder are convertible at the time of such vote. All preferred stockholders are entitled to vote on all matters upon which holders of common stock have the right to vote, other than matters that must by law be voted by class or series vote.

Dividends—The holders of preferred stock are entitled to receive dividends, when and if declared by the board of directors of the Company, prior and in preference to any dividend on the common stock of the Company, in an amount equal to $0.9681 per share of Series A per annum, or $1.6458 per share of Series B per annum, subject to adjustment in the event of any stock dividend, stock split, combination or other similar recapitalization. The dividends are non-cumulative, and no such dividends have been declared to date. After payment of dividends on the Series A and Series B, any additional dividends shall be distributed among all holders of common stock and preferred stock based on the number of shares of common stock that would be held by each such holder if all shares of preferred stock were converted to common stock.

Liquidation Preference—In the event of any voluntary or involuntary liquidation, dissolution or winding-up of the Company, or a deemed liquidation event of the Company (which includes certain mergers, acquisitions and asset transfers), the holders of preferred stock shall be entitled to receive on a pari passu basis, out of the assets or consideration available for distribution in connection with such event and before any payment will be made to the holders of common stock, an amount per share equal to the original issuance price of the preferred stock ($0.9681 per share for the Series A and $1.6458 per share for the Series B), plus any declared but unpaid dividends on such shares. The treatment of an event as a deemed liquidation event may be waived by the vote or written consent of the holders of at least 66% of the Series B (the “Requisite Preferred Holders”).

If the assets or consideration available for distribution to the stockholders are insufficient to pay the Series B and Series A liquidation amounts in full, then the holders of Series B and Series A shall share ratably in any distribution of the assets in proportion to the respective amounts which would otherwise be payable in respect of the shares of Series B and Series A held by them upon distribution if all amounts payable were paid in full.

After payment of the Series B and Series A liquidation amounts in full, all of the remaining assets of the Company available for distribution to the stockholders shall be distributed among the holders of the preferred stock and common stock, pro rata based on the number of shares held by each such holder on an as converted to common stock basis.

Conversion—Shares of preferred stock are convertible into common stock at the option of the holder at any time and without payment of any additional consideration. Each share of Series A is convertible into a number of fully paid shares of common stock as is determined by dividing the Series A original issuance price of $0.9681 by the Series A conversion price (initially equal to $0.9681). Each share of Series B is convertible into a number of fully paid shares of common stock as is determined by dividing the Series B original issuance price of $1.6458 by the Series B conversion price (initially equal to $1.6458). Further, the conversion rates of preferred stock are subject to adjustment based upon the occurrence of certain future events as defined in the Company’s certificate of incorporation. The Company effected a 1-for-6.359 reverse stock split in October 2021. Upon the initial public offering 127,537,173 shares of convertible preferred stock were converted to 20,056,145 shares of common stock.

Common Stock

9 Months Ended

Sep. 30, 2021

Equity [Abstract]

Common Stock

7. Common Stock

The Company was authorized to issue up to 167,000,000 and 40,300,000 shares of common stock as of September 30, 2021 and December 31, 2020, respectively, of which 2,194,326 and 2,177,956 shares were issued as of September 30, 2021 and December 31, 2020, respectively, 1,639,600 and 1,289,342 shares were outstanding at September 30, 2021 and December 31, 2020, respectively.

Voting, dividend and liquidation rights of the holders of the common stock are subject to and qualified by the rights, powers and preferences of the holders of the preferred stock.

Voting—Each holder of outstanding shares of common stock shall be entitled to one vote in respect of each share. The holders of outstanding shares of common stock, voting together as a single class, shall be entitled to elect one director. The number of authorized shares of common stock may be increased or decreased by the affirmative vote of a majority of the outstanding shares of common stock and preferred stock voting together as a single class.

Reserved Shares—As of September 30, 2021, the Company reserved the following shares of common stock for issuance upon conversion of the outstanding convertible preferred stock and exercise of stock options:


Series A convertible preferred stock			3,573,659
Series B convertible preferred stock			16,482,486
Unvested restricted stock options			554,724
Stock options available for issuance			3,852,807
Stock options outstanding			3,530,706
Employee stock purchase plan			424,595
Total			28,418,977

- Definition

The entire disclosure for shareholders' equity comprised of portions attributable to the parent entity and noncontrolling interest, including other comprehensive income. Includes, but is not limited to, balances of common stock, preferred stock, additional paid-in capital, other capital and retained earnings, accumulated balance for each classification of other comprehensive income and amount of comprehensive income.

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+ Details

Stock-Based Compensation

9 Months Ended

Sep. 30, 2021

Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]

Stock-Based Compensation

8. Stock-Based Compensation

2021 Equity Incentive Plan

On September 27, 2021, the Company’s board of directors and stockholders approved the 2021 Equity Incentive Plan (the “2021 Plan”), which became effective on October 7, 2021, when the Company’s registration statement was declared effective by the SEC. The 2021 Plan replaced the 2019 Plan as the Company’s board of directors has determined not to make additional awards under the 2019 Plan following the closing of the Company’s initial public offering. However, the 2019 Plan will continue to govern outstanding equity awards granted under the plan. The 2021 Plan allows the Company to make equity-based and cash-based incentive awards to its officers, employees, directors and consultants. The Company has initially reserved 3,852,807 shares of its common stock for the issuance of awards under the 2021 Plan.

2019 Equity Incentive Plan

In 2019, the Company established the 2019 Plan, under which the Company grant options and restricted stock to its employees and certain non-employees. The maximum number of shares of common stock reserved for issuance under the 2019 Plan is 4,042,408 shares. All the shares of common stock were issued under the 2019 Plan through September 30, 2021.

The Company may grant options to purchase authorized but unissued shares of the Company’s common stock. Options granted under the 2019 Plan include incentive stock options that can be granted only to the Company’s employees and non-statutory stock options that can be granted to the Company’s employees, consultants, advisors and directors. The 2019 Plan also permits the Company to issue restricted stock awards.

The exercise prices, vesting and other restrictions of the awards to be granted under the 2019 Plan are determined by the board of directors, except that no stock option may be issued with an exercise price less than the fair market value of the common stock at the date of the grant or have a term in excess of ten years. Options granted under the 2019 Plan are exercisable in whole or in part at any time subsequent to vesting.

Stock Options

The summary of stock option activity for the nine months ended September 30, 2021 (in thousands, except share and per share amounts):


	Number of Shares			Weighted Average Exercise Price		Weighted Average Remaining Contractual Term		Aggregate Intrinsic Value
						(Years)
Outstanding at January 1, 2021		220,383		$	0.64		9.4	$	348
Granted		3,672,351			6.38		9.6
Exercised		(16,370	)		0.88
Forfeited		(345,658	)		5.29
Outstanding at September 30, 2021		3,530,706		$	6.16		9.7	$	34,755
Exercisable at September 30, 2021		927,403		$	4.89		9.6	$	10,304

The aggregate intrinsic value is calculated as the difference between the exercise price of all outstanding and exercisable stock options and the fair value of the Company’s common stock of $16 per share as of September 30, 2021. The options granted during the three and nine months ended September 30, 2021 had a weighted-average fair value of $5.59 and $4.15 per share, respectively, and $0.04 per share for the options granted during the three and nine months ended September 30, 2020.

The Company estimated the fair value of each option on the date of grant using the Black-Scholes option pricing model applying the weighted-average assumptions in the following table:


	Three Months Ended September 30,		Nine Months Ended September 30,
	2021	2020	2021	2020
Expected volatility	72.88% - 73.13%	87.40% - 87.40%	72.88% - 75.17%	82.80% - 87.40%
Risk-free interest rate	0.81% - 0.96%	0.38% - 0.38%	0.81% - 1.16%	0.38% - 0.56%
Expected dividend yield	0.00%	0.00%	0.00%	0.00%
Expected term (in years)	6.00 - 6.08	6.02 - 6.08	6.00 - 6.08	6.02 - 6.08

Stock-based compensation expense related to stock options recorded is as follows (in thousands):


	Three Months Ended September 30,				Nine Months Ended September 30,
	2021		2020		2021		2020
Research and development	$	96	$	4	$	1,106	$	10
General and administrative		211		8		2,223		19
Total	$	307	$	12	$	3,329	$	29

The Company has an aggregate $10.8 million of gross unrecognized stock-based compensation expense as of September 30, 2021 remaining to be amortized over a weighted average period of 2.84 years. The Company has not recognized and does not expect to recognize in the near future, any tax benefit related to employee stock-based compensation expense as a result of the full valuation allowance related to its net deferred tax assets.

Restricted Stock Awards

The Company issued 994,650 shares of restricted common stock to the employee co-founders and certain non-employee consultants in 2019. The shares of restricted common stock were issued pursuant to standalone restricted stock purchase agreements that are independent of the 2019 Plan and 2021 Plan. The shares of restricted common stock carried a purchase price equivalent of $0.01 per share. The compensation cost was measured based on the fair value of the underlying common stock less the purchase price of the restricted common stock and the Company recognizes compensation costs over the requisite service period.

Under the terms of the restricted stock purchase agreements, the Company has a repurchase option whereby it has the right to repurchase any unvested shares upon termination at a price per share equal to the lesser of: (i) the fair market value of the Company’s common stock on the date of repurchase and (ii) the original purchase price. The shares of restricted common stock issued to the Company’s co-founders and non-employee consultants vest based on a predefined number of shares.

The Company recognized an associated deposit liability for restricted stock awards issued pursuant to standalone restricted stock purchase agreements upon issuance based on the purchase price of the awards as the unvested shares are subject to repurchase upon termination. As the awards of restricted stock vest, the Company reclassifies the deposit liability to additional paid-in capital.

The summary of restricted stock activity for the nine months ended September 30, 2021:


	Restricted Stock Number of Shares
Non-vested, January 1, 2021		888,612
Vested		(333,888	)
Non-vested, September 30, 2021		554,724

The Company has recorded stock-based compensation expense related to the restricted stock of $5 thousand and $6 thousand for the three months ended September 30, 2021 and 2020, respectively, and $17 thousand for the nine months ended September 30, 2021 and 2020. The Company has an aggregate $30 thousand of gross unrecognized restricted stock-based compensation expense as of September 30, 2021 remaining to be amortized over a weighted average period of 1.7 years.

2021 Employee Stock Purchase Plan

On September 27, 2021, the Company’s board of directors and stockholders approved the 2021 Employee Stock Purchase Plan (the “2021 ESPP”), which became effective on October 7, 2021, when the Company’s registration statement was declared effective by the SEC. The 2021 ESPP reserved and authorized the issuance of up to a total of 424,595 shares of common stock to participating employees. No shares are issued under 2021 ESPP plan as of the date of issuance of these unaudited condensed consolidated financial statements.

Income Taxes

9 Months Ended

Sep. 30, 2021

Income Tax Disclosure [Abstract]

Income Taxes

9. Income Taxes

The Company’s effective tax rate from continuing operations was 0% for each of the three and nine months ended September 30, 2021 and 2020. The Company has not recorded a federal income tax provision for the nine months ended September 30, 2021 and 2020. The Company recorded a nominal state and local income tax provision for the nine months ended September 30, 2021 and $0 for the nine months ended September 30, 2020.

The Company assesses the realizability of the deferred tax assets at each reporting date. The Company continues to maintain a full valuation allowance for its U.S. federal and state deferred tax assets, which significantly consists of net operating losses and tax credits. If certain substantial changes in the entity's ownership occur, there may be an annual limitation on the amount of the carryforwards that can be utilized. The Company will continue to assess the need for a valuation allowance on its deferred tax assets.

- Definition

The entire disclosure for income taxes. Disclosures may include net deferred tax liability or asset recognized in an enterprise's statement of financial position, net change during the year in the total valuation allowance, approximate tax effect of each type of temporary difference and carryforward that gives rise to a significant portion of deferred tax liabilities and deferred tax assets, utilization of a tax carryback, and tax uncertainties information.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

Net Loss per Common Share

9 Months Ended

Sep. 30, 2021

Earnings Per Share [Abstract]

Net Loss per Common Share

10. Net Loss per Common Share

Basic and diluted net loss per common share was calculated as follows (in thousands, except share and per share amounts):


	Three Months Ended September 30,						Nine Months Ended September 30,
	2021			2020			2021			2020
Numerator:
Net loss	$	(14,175	)	$	(3,191	)	$	(59,146	)	$	(8,249	)
Denominator:
Weighted-average common shares outstanding, basic and diluted		1,581,610			1,088,222			1,468,777			979,081
Net loss per common share, basic and diluted	$	(8.96	)	$	(2.93	)	$	(40.27	)	$	(8.43	)

The Company’s potentially dilutive securities, which include convertible preferred stock, restricted stock, and stock options, have been excluded from the computation of diluted net loss per common share as the effect would be to reduce the net loss per share. Therefore, the weighted-average number of common shares 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 at September 30, 2021 and 2020 because including them would have had an anti-dilutive effect:


	September 30,
	2021		2020
Convertible Preferred Stock		20,056,145		3,573,659
Unvested Restricted Stock		554,724		1,044,516
Stock options outstanding		3,530,706		168,296
Stock options available for issuance		3,852,807		87,836
Employee stock purchase plan		424,595		—
Total		28,418,977		4,874,307

Related Parties

9 Months Ended

Sep. 30, 2021

Related Parties

11. Related Parties

In 2020, the Company entered into agreements with several Scientific Advisory Board (“SAB”) members and paid them monthly amounts, ranging from $3 thousand to $5 thousand per month. No board member was paid more than $0.1 million individually for either of the three and nine months ended September 30, 2021 and 2020, in the aggregate, all board members were paid less than $0.1 million for both periods combined.

In 2020, the Company entered into the University License Agreement, as well as a sponsored research agreement, with the University, which had previously purchased 309,885 shares of the Company’s Series A Preferred Stock as part of the Company’s 2019 Series A Financing. In partial consideration for the license from the University, the Company issued to the University 311,076 shares (48,919 shares post reverse stock split) of its Common Stock in 2020. Refer to Note 5 for additional discussion.

In 2020, the Company entered into the Pfizer License Agreement. As the effective date of the Pfizer License Agreement was in March 2021. During the nine months ended September 30, 2021, the Company incurred a combined $25.0 million (which was recorded as research and development expenses), consisting of an upfront fee equal to a cash payment of $5.0 million and the issuance of 12,152,145 shares of Series B Convertible Preferred Stock with a value of $20.0 million in 2021 to Pfizer. Refer to Note 5 for additional discussion.

In December 2020, the Company entered into the LegoChem License Agreement and the Opt-In Agreement with LegoChem. Pursuant to the LegoChem License Agreement, the Company paid $0.5 million in December 2020 and $9.0 million during the nine months ended September 30, 2021 to LegoChem. The Company settled the outstanding liability of $0.5 million through the issuance of 303,804 shares Series B Convertible Preferred Stock as part of its Series B financing in March 2021. LegoChem exercised its option in December 2020 under the Opt-In Agreement and paid $8.0 million to the Company in April 2021, in exchange for the right to receive a milestone payment of $9.6 million upon the earliest to occur of the certain events, including the date of pricing or offer of the first public offering of its common stock or if the Company is the subject of a change of control transaction. Refer to Note 5 for additional discussion.

Commitments and Contingencies

9 Months Ended

Sep. 30, 2021

Commitments And Contingencies Disclosure [Abstract]

Commitments and Contingencies

12. Commitments and Contingencies

Commitments

In the normal course of business, the Company enters into agreements with contract research organizations (“CROs”), research programs and with vendors for nonclinical studies, manufacturing and other services and products for operating purposes, which agreements are generally cancellable by the Company at any time, subject to payment of remaining obligations under binding purchase orders and, in certain cases, nominal early-termination fees. These commitments are not deemed significant.

Operating Leases

As of September 30, 2021, the Company had two operating leases, where the Company is the lessee or sublessee, for office and laboratory space. Lease terms are through 2022. The Company had no finance leases as of September 30, 2021.

The Company’s rent expense was $0.2 million and $0.5 million for the three and nine months ended September 30, 2021 and 2020, respectively. Future minimum lease obligations as of September 30, 2021 is $0.3 million.

In addition to above lease commitment, on September 29, 2021, the Company entered into a lease agreement for an office and laboratory space in Boston, Massachusetts. The lease will expire on December 31, 2032 and have scheduled rent increases each year of 3%. There is an additional five-year option to extend the lease beyond December 31, 2032. The future undiscounted operating lease payments (base rent) under the lease agreement is $33.8 million over an initial lease period of approximately ten years. The Company will record the right-of-use asset and operating lease liability upon obtaining the possession of the property, which it expects to happen in the second quarter of 2022.

Contingencies

In March 2020, COVID-19 disease was declared a pandemic by the World Health Organization. The COVID-19 pandemic is disrupting supply chains and affecting production and sales across a range of industries. Currently, the Company has not suffered significant adverse consequences as a result of the COVID-19 pandemic. The extent of the impact of COVID-19 on the Company’s future operational and financial performance will depend on certain developments, including the duration and spread of the pandemic, including its variants, impact on employees and vendors all of which are uncertain and cannot be predicted. At this point, the extent to which COVID-19 may impact the Company’s future financial condition or results of operations is uncertain.

Basis of Presentation and Summary of Significant Accounting Policies (Policies)	9 Months Ended
	Sep. 30, 2021
Accounting Policies [Abstract]
Nature of Business	Nature of Business Pyxis Oncology, Inc. (the “Company”), a Delaware corporation, was founded in June 2018 and launched its operations in July 2019. The Company is a preclinical oncology company focused on developing an arsenal of next-generation therapeutics to target difficult-to-treat cancers and improve quality of life for patients. The Company develops its product candidates with the objective to directly kill tumor cells, and to address the underlying pathologies created by cancer that enable its uncontrollable proliferation and immune evasion. Since the Company’s launch in 2019, the Company has developed a broad portfolio of novel antibody drug conjugate, or ADC, product candidates and monoclonal antibody, or mAb, preclinical discovery programs that the Company is developing as monotherapies and in combination with other therapies.
Basis of Presentation	Basis of Presentation The Company’s fiscal year ends on December 31 and its first three fiscal quarters end on March 31, June 30 and September 30. The accompanying condensed consolidated financial statements are unaudited. The unaudited condensed consolidated financial statements of the Company have been prepared in accordance with generally accepted accounting principles in the United States (“U.S. GAAP”) and follow the requirements of the Securities and Exchange Commission (“SEC”) for interim financial reporting. Accordingly, they do not include all of the information and disclosures required by U.S. GAAP for complete financial statements as certain footnotes or other financial information that are normally required by U.S. GAAP can be condensed or omitted. The unaudited condensed consolidated financial statements have been prepared on the same basis as the audited consolidated financial statements. The unaudited condensed consolidated financial statements include the accounts of the Company and its wholly-owned subsidiary. The Company has no unconsolidated subsidiaries. All intercompany balances and transactions have been eliminated in consolidation. Any reference in these notes to applicable guidance is meant to refer to the authoritative U.S. GAAP as found in the Accounting Standards Codification (“ASC”) and Accounting Standards Updates (“ASU”) of the Financial Accounting Standards Board (“FASB”). In the opinion of management, the unaudited condensed consolidated financial statements include all normal and recurring adjustments that are considered necessary for the fair statement of results for the interim periods. The results for the three and nine months ended September 30, 2021 are not necessarily indicative of those expected for the year ending December 31, 2021 or for any future period. The condensed consolidated balance sheet as of December 31, 2020 included herein was derived from the audited consolidated financial statements as of that date. These unaudited condensed consolidated financial statements should be read in conjunction with the Company’s audited consolidated financial statements and the related notes thereto for the year ended December 31, 2020, included in the Company’s final prospectus filed with the SEC pursuant to Rule 424(b)(4) on October 8, 2021 (“Final Prospectus”).
Initial Public Offering	Initial Public Offering In October 2021, the Company completed its initial public offering (“IPO”), for the sale and issuance of 10,500,000 shares of its common stock at $16.00 per share. The Company received net proceeds of approximately $152.2 million, after deducting underwriters’ discounts and commissions and other issuance costs. Prior to the IPO, all deferred offering costs were capitalized in other noncurrent assets on the condensed consolidated balance sheets. Deferred offering costs of $3.5 million, primarily consisting of accounting, legal, and other fees related to the Company’s IPO, will be offset against the IPO proceeds upon the closing of the Company’s IPO in October 2021. As of September 30, 2021 unpaid deferred offering costs totaled $1.1 million.
Reverse Stock Split	Reverse Stock Split On October 1, 2021, the Company’s board of directors approved and effected a 1-for-6.359 reverse stock split of its issued and outstanding common stock and stock option awards. All issued and outstanding shares of common stock, stock option awards and per share data have been adjusted in these unaudited condensed consolidated financial statements, on a retrospective basis, to reflect the reverse stock split for all periods presented. The par value of the common stock and preferred stock was not adjusted as a result of the reverse stock split. The shares of common stock underlying outstanding stock options and other equity instruments were proportionately reduced and the respective exercise prices, if applicable, were proportionately increased in accordance with the terms of the agreements governing such securities. In connection with the IPO, all 127,537,173 shares of convertible preferred stock automatically converted into 20,056,145 shares of common stock. Stockholders entitled to fractional shares as a result of the reverse stock split received a cash payment in lieu of receiving fractional shares.
Liquidity	Liquidity As of September 30, 2021, the Company had an accumulated deficit of $74.9 million. The Company has incurred losses and negative cash flows from operations since inception, including net losses of $59.1 million and $8.2 million for the nine months ended September 30, 2021 and 2020, respectively. The Company has not generated any revenues to date and does not anticipate generating any revenues unless and until it successfully completes development and obtains regulatory approval for its current or any future product candidates. The Company expects that its operating losses and negative cash flows will continue for the foreseeable future as the Company continues to expand its research and development programs and develop its product candidates. In October 2021, the Company raised approximately $152.2 million in net proceeds in an IPO. The Company currently expects that its existing cash and cash equivalents of $133.5 million as of September 30, 2021 along with proceeds from IPO will be sufficient to fund its operating expenses and capital requirements at least twelve months from the date these unaudited condensed consolidated financial statements are issued. Additional funding may be necessary to fund future clinical and preclinical activities. The Company plans to continue to fund its losses from operations and capital funding needs through public or private equity, convertible or debt financings or other sources. If the Company is not able to secure adequate additional funding, the Company may be forced to make reductions in spending, extend payment terms with suppliers, liquidate assets where possible, or suspend or curtail planned programs. Any of these actions could materially harm the Company’s business, results of operations and future prospects.
Use of Estimates	Use of Estimates The preparation of unaudited condensed consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the amounts reported in the unaudited condensed consolidated financial statements and accompanying notes. The Company regularly evaluates estimates and assumptions related to assets, liabilities, stock-based compensation, derivative liability, operating leases, and research and development costs. The Company bases its estimates and assumptions on historical experience and on various other factors that it believes to be reasonable under the circumstances, the results of which form the basis for making judgments about the carrying values of assets and liabilities that are not readily apparent from other sources. Actual results could differ from those estimates.
Concentration of Credit Risk	Concentration of Credit Risks Financial instruments that subject the Company to significant concentrations of credit risk consist primarily of cash and cash equivalents. The Company’s cash and cash equivalents are held at an accredited financial institution and the Company has not experienced any losses in such accounts. The Company maintains its cash in bank deposit accounts, which at times may exceed federally insured limits. The Company’s cash equivalents consist primarily of short-term money market funds held in accredited financial institutions. The Company believes it is not exposed to any significant risk in cash and cash equivalents.
Significant Accounting Policies	Significant Accounting Policies There have been no changes to the Company’s significant accounting policies disclosed in “Note 2 – Summary of Significant Accounting Policies” of the Company’s Final Prospectus.
Recent Accounting Pronouncements	Recent Accounting Pronouncements Recent authoritative guidance issued by the FASB (including technical corrections to the ASC), the American Institute of Certified Public Accountants, and the SEC did not, or are not expected to, have a material impact on the Company’s unaudited condensed consolidated financial statements and related disclosures.

Fair Value Measurements (Tables)

9 Months Ended

Sep. 30, 2021

Fair Value Disclosures [Abstract]

Summary of Financial Instruments Carried at Fair Value on Recurring Basis


	Fair Value Measurements at September 30, 2021
	Level 1		Level 2		Level 3		Total
Assets
Cash equivalents	$	128,447	$	—	$	—	$	128,447
Liabilities
Derivative liability	$	—	$	—	$	9,190	$	9,190


	Fair Value Measurements at December 31, 2020
	Level 1		Level 2		Level 3		Total
Assets
Cash equivalents	$	6,996	$	—	$	—	$	6,996

Summary of Changes in Level 3 Fair Value Measurements

The following tables provide a summary of changes in our Level 3 fair value measurements for the three and nine months ended September 30, 2021:



	Three months ended		Nine months ended
	September 30, 2021
($ in thousands)
Derivative liability balance at the beginning of the period	$	6,630	$	—
Recognition of derivative liability		—		3,369
Change in fair value recorded in earnings		2,560		5,821
Balance as of September 30, 2021	$	9,190	$	9,190

- Definition

Tabular disclosure of financial instruments measured at fair value, including those classified in shareholders' equity measured on a recurring or nonrecurring basis. Disclosures include, but are not limited to, fair value measurements recorded and the reasons for the measurements, level within the fair value hierarchy in which the fair value measurements are categorized and transfers between levels 1 and 2. Nonrecurring fair value measurements are those that are required or permitted in the statement of financial position in particular circumstances.

+ References + Details

Common Stock (Tables)

9 Months Ended

Sep. 30, 2021

Equity [Abstract]

Common Stock Reserved for Issuance Upon Conversion of Outstanding Convertible Preferred Stock and Exercise of Stock Options

As of September 30, 2021, the Company reserved the following shares of common stock for issuance upon conversion of the outstanding convertible preferred stock and exercise of stock options:


Series A convertible preferred stock			3,573,659
Series B convertible preferred stock			16,482,486
Unvested restricted stock options			554,724
Stock options available for issuance			3,852,807
Stock options outstanding			3,530,706
Employee stock purchase plan			424,595
Total			28,418,977

Stock-Based Compensation (Tables)

9 Months Ended

Sep. 30, 2021

Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]

Summary of Stock Option Activity

The summary of stock option activity for the nine months ended September 30, 2021 (in thousands, except share and per share amounts):


	Number of Shares			Weighted Average Exercise Price		Weighted Average Remaining Contractual Term		Aggregate Intrinsic Value
						(Years)
Outstanding at January 1, 2021		220,383		$	0.64		9.4	$	348
Granted		3,672,351			6.38		9.6
Exercised		(16,370	)		0.88
Forfeited		(345,658	)		5.29
Outstanding at September 30, 2021		3,530,706		$	6.16		9.7	$	34,755
Exercisable at September 30, 2021		927,403		$	4.89		9.6	$	10,304

Schedule of Estimated Fair Value Assumptions

The Company estimated the fair value of each option on the date of grant using the Black-Scholes option pricing model applying the weighted-average assumptions in the following table:


	Three Months Ended September 30,		Nine Months Ended September 30,
	2021	2020	2021	2020
Expected volatility	72.88% - 73.13%	87.40% - 87.40%	72.88% - 75.17%	82.80% - 87.40%
Risk-free interest rate	0.81% - 0.96%	0.38% - 0.38%	0.81% - 1.16%	0.38% - 0.56%
Expected dividend yield	0.00%	0.00%	0.00%	0.00%
Expected term (in years)	6.00 - 6.08	6.02 - 6.08	6.00 - 6.08	6.02 - 6.08

Summary of Stock-Based Compensation Expense

Stock-based compensation expense related to stock options recorded is as follows (in thousands):


	Three Months Ended September 30,				Nine Months Ended September 30,
	2021		2020		2021		2020
Research and development	$	96	$	4	$	1,106	$	10
General and administrative		211		8		2,223		19
Total	$	307	$	12	$	3,329	$	29

Summary of Restricted Stock Activity

The summary of restricted stock activity for the nine months ended September 30, 2021:


	Restricted Stock Number of Shares
Non-vested, January 1, 2021		888,612
Vested		(333,888	)
Non-vested, September 30, 2021		554,724

Net Loss per Common Share (Tables)

9 Months Ended

Sep. 30, 2021

Earnings Per Share [Abstract]

Summary of Basic and Diluted Net Loss Per Common Share

Basic and diluted net loss per common share was calculated as follows (in thousands, except share and per share amounts):


	Three Months Ended September 30,						Nine Months Ended September 30,
	2021			2020			2021			2020
Numerator:
Net loss	$	(14,175	)	$	(3,191	)	$	(59,146	)	$	(8,249	)
Denominator:
Weighted-average common shares outstanding, basic and diluted		1,581,610			1,088,222			1,468,777			979,081
Net loss per common share, basic and diluted	$	(8.96	)	$	(2.93	)	$	(40.27	)	$	(8.43	)

Anti-Dilutive Effect Excluded from Computation of Diluted Net Loss Per Share Attributable to Common Stockholders


	September 30,
	2021		2020
Convertible Preferred Stock		20,056,145		3,573,659
Unvested Restricted Stock		554,724		1,044,516
Stock options outstanding		3,530,706		168,296
Stock options available for issuance		3,852,807		87,836
Employee stock purchase plan		424,595		—
Total		28,418,977		4,874,307

Basis of Presentation and Summary of Significant Accounting Policies - Additional Information (Details) $ / shares in Units, $ in Thousands		1 Months Ended	3 Months Ended						9 Months Ended
	Oct. 01, 2021 shares	Oct. 31, 2021 USD ($) $ / shares shares	Sep. 30, 2021 USD ($)	Jun. 30, 2021 USD ($)	Mar. 31, 2021 USD ($)	Sep. 30, 2020 USD ($)	Jun. 30, 2020 USD ($) shares	Mar. 31, 2020 USD ($)	Sep. 30, 2021 USD ($)	Sep. 30, 2020 USD ($)	Dec. 31, 2020 USD ($)
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Deferred offering costs			$ 1,100						$ 1,100
Accumulated deficit			(74,889)						(74,889)		$ (15,743)
Net loss			(14,175)	$ (8,003)	$ (36,968)	$ (3,191)	$ (3,100)	$ (1,958)	(59,146)	$ (8,249)
Cash and cash equivalents			$ 133,477			$ 11,246			$ 133,477	$ 11,246	$ 8,080
Subsequent Event
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Reverse stock split, conversion ratio	0.15725743	0.15725743
Common Stock
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Stock issued \| shares							48,919
Initial Public Offering \| Subsequent Event
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Deferred offering costs		$ 3,500
Stock automatically converted \| shares		127,537,173
Net proceeds		$ 152,200
Initial Public Offering \| Subsequent Event \| Convertible Preferred Stock
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Stock automatically converted \| shares	127,537,173
Initial Public Offering \| Subsequent Event \| Convertible Common Stock
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Stock automatically converted \| shares	20,056,145
Initial Public Offering \| Common Stock \| Subsequent Event
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Stock issued \| shares		10,500,000
Common stock public offering price per share \| $ / shares		$ 16.00
Net proceeds from issuance initial public offering		$ 152,200

Fair Value Measurements - Summary of Financial Instruments Carried at Fair Value on Recurring Basis (Details) - Fair Value, Recurring - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Assets
Cash equivalents	$ 128,447	$ 6,996
Liabilities
Derivative liability	9,190
Level 1
Assets
Cash equivalents	128,447	$ 6,996
Level 3
Liabilities
Derivative liability	$ 9,190

Fair Value Measurements - Additional Information (Details) - USD ($)	Sep. 30, 2021	Dec. 31, 2020
Fair Value Disclosures [Abstract]
Assets measured at fair value	$ 0	$ 0
Liabilities measured at fair value	$ 0	$ 0

Fair Value Measurements - Summary of Changes in Level 3 Fair Value Measurements (Details) - Derivative Liability - Level 3 - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2021
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Derivative liability balance at the beginning of the period	$ 6,630
Recognition of derivative liability		$ 3,369
Change in fair value recorded in earnings	2,560	5,821
Balance as of September 30, 2021	$ 9,190	$ 9,190

Joint Venture - Additional Information (Details) - USD ($)	3 Months Ended	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2021	Mar. 31, 2021
Schedule Of Equity Method Investments [Line Items]
Service fee income from related party		$ 181,000
Voxall
Schedule Of Equity Method Investments [Line Items]
Initial contribution			$ 50,000
Service fee income from related party	$ 0	200,000
Losses incurred	100,000	800,000
Promissory note issued	$ 0	$ 200,000
Equity method investment, description		As the Company has no commitment to fund the losses of the equity method investment, the carrying value of the equity method investment has not been reduced below zero.
Voxall \| Alloy Therapeutics, Inc.
Schedule Of Equity Method Investments [Line Items]
Percentage of voting membership units			50.00%
Initial contribution			$ 50,000

- Definition

Amount after tax of income (loss) from continuing operations including portion attributable to the noncontrolling interest.

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+ Details

License Agreements - Additional Information (Details) - USD ($)	1 Months Ended				3 Months Ended		9 Months Ended
	Apr. 30, 2021	Mar. 31, 2021	Dec. 31, 2020	Apr. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Jan. 31, 2021
Research And Development Arrangement Contract To Perform For Others [Line Items]
Research and development expense					$ 7,849,000	$ 2,425,000	$ 43,828,000	$ 5,909,000
Proceeds from stock options exercised							14,000	31,000
Pfizer License Agreement
Research And Development Arrangement Contract To Perform For Others [Line Items]
Research and development expense					0		25,000,000.0
Milestone and royalties incurred					0		0
Upfront payments							$ 5,000,000.0
Pfizer License Agreement \| Series B Convertible Preferred Stock
Research And Development Arrangement Contract To Perform For Others [Line Items]
Issuance of convertible preferred stock shares							12,152,145
Issuance of convertible preferred stock value					20,000,000.0		$ 20,000,000.0
LegoChem License Agreement
Research And Development Arrangement Contract To Perform For Others [Line Items]
Research and development expense							9,000,000.0
Milestone and royalties incurred					0		0
Payments to purchase licensed products		$ 9,000,000.0	$ 500,000				9,000,000.0
Licensed product estimated cost			7,000,000.0
Accrued research and development expenses			$ 500,000
Settlement on outstanding liability		$ 500,000
Proceeds from stock options exercised	$ 8,000,000.0			$ 8,000,000.0
Extra milestone payment				$ 9,600,000
Derivative liability					9,200,000		9,200,000		$ 3,400,000
Fair value adjustment to the derivative liability					2,600,000		5,800,000
Other milestone and royalties incurred					0		0
LegoChem License Agreement \| Series B Convertible Preferred Stock
Research And Development Arrangement Contract To Perform For Others [Line Items]
Issuance of convertible preferred stock shares		303,804
University License Agreement
Research And Development Arrangement Contract To Perform For Others [Line Items]
Stock issued				311,076
Stock issued, shares, reverse stock splits				48,919
Research and development expense					0		0	$ 3,000
Milestone and royalties incurred					$ 0		$ 0

Convertible Preferred Stock - Additional Information (Details) $ / shares in Units, $ in Thousands		1 Months Ended		2 Months Ended	9 Months Ended
	Oct. 01, 2021	Oct. 31, 2021 $ / shares shares	Mar. 31, 2021 USD ($) $ / shares shares	Jul. 31, 2019 USD ($) $ / shares shares	Sep. 30, 2021 USD ($) $ / shares shares	Mar. 05, 2021 $ / shares	Dec. 31, 2020 shares	Jun. 30, 2019 $ / shares shares
Temporary Equity [Line Items]
Issuance costs \| $					$ 2,451
Net proceeds from issuance of convertible preferred stock \| $					$ 151,581
Subsequent Event
Temporary Equity [Line Items]
Reverse stock split description		1-for-6.359 reverse stock split
Reverse stock split, conversion ratio	0.15725743	0.15725743
Subsequent Event \| Common Stock
Temporary Equity [Line Items]
Convertible preferred stock shares issued upon conversion \| shares		20,056,145
Initial Public Offering \| Subsequent Event
Temporary Equity [Line Items]
Number of preferred shares conversion \| shares		127,537,173
Initial Public Offering \| Subsequent Event \| Common Stock
Temporary Equity [Line Items]
Share sale price per share \| $ / shares		$ 16.00
Series A Convertible Preferred Stock
Temporary Equity [Line Items]
Share sale price per share \| $ / shares								$ 0.9681
Shares Issued \| shares					22,724,925		22,724,925
Preferred stock, dividends per share, declared \| $ / shares					$ 0
Preferred stock, dividend per share \| $ / shares					$ 0.9681
Preferred stock, initial conversion price \| $ / shares								0.9681
Series B Convertible Preferred Stock
Temporary Equity [Line Items]
Share sale price per share \| $ / shares						$ 1.6458
Shares Issued \| shares					104,812,248		0
Preferred stock, dividends per share, declared \| $ / shares					$ 0
Preferred stock, dividend per share \| $ / shares					$ 1.6458
Preferred stock, initial conversion price \| $ / shares						1.6458
Series B Convertible Preferred Stock \| Minimum
Temporary Equity [Line Items]
Percentage of vote required to waived of deemed liquidation					66.00%
Securities Purchase Agreement \| Series A Convertible Preferred Stock
Temporary Equity [Line Items]
Share sale price per share \| $ / shares				$ 0.9681				$ 0.9681
Shares Issued \| shares				22,724,925				22,724,925
Gross cash proceeds from issuance of convertible preferred stock \| $				$ 22,000
Issuance costs \| $				100
Net proceeds from issuance of convertible preferred stock \| $				$ 21,900
Securities Purchase Agreement \| Series A Convertible Preferred Stock \| Subsequent Event
Temporary Equity [Line Items]
Reverse stock split description		1-for-6.359 reverse stock split
Reverse stock split, conversion ratio		0.15725743
Securities Purchase Agreement \| Series A Convertible Preferred Stock \| Initial Public Offering \| Subsequent Event
Temporary Equity [Line Items]
Number of preferred shares conversion \| shares		22,724,925
Securities Purchase Agreement \| Series A Convertible Preferred Stock \| Initial Public Offering \| Subsequent Event \| Common Stock
Temporary Equity [Line Items]
Convertible preferred stock shares issued upon conversion \| shares		3,573,659
Securities Purchase Agreement \| Series B Convertible Preferred Stock
Temporary Equity [Line Items]
Share sale price per share \| $ / shares			$ 1.6458			$ 1.6458
Shares Issued \| shares			92,356,299
Gross cash proceeds from issuance of convertible preferred stock \| $			$ 152,000
Issuance costs \| $			400
Net proceeds from issuance of convertible preferred stock \| $			$ 151,600
Securities Purchase Agreement \| Series B Convertible Preferred Stock \| Subsequent Event
Temporary Equity [Line Items]
Reverse stock split description		1-for-6.359 reverse stock split
Reverse stock split, conversion ratio		0.15725743
Securities Purchase Agreement \| Series B Convertible Preferred Stock \| Subsequent Event \| Common Stock
Temporary Equity [Line Items]
Convertible preferred stock shares issued upon conversion \| shares		16,482,486
Securities Purchase Agreement \| Series B Convertible Preferred Stock \| Initial Public Offering \| Subsequent Event
Temporary Equity [Line Items]
Number of preferred shares conversion \| shares		104,812,248
Agreements with Pfizer, Inc. and LegoChem Biosciences Inc. \| Series B Convertible Preferred Stock
Temporary Equity [Line Items]
Shares Issued \| shares			12,455,949
Net proceeds from issuance of convertible preferred stock \| $			$ 20,500

Common Stock - Additional Information (Details)	9 Months Ended
Common Stock - Additional Information (Details)	Sep. 30, 2021 Director shares	Dec. 31, 2020 shares
Equity [Abstract]
Common stock, shares authorized	167,000,000	40,300,000
Common stock, shares issued	2,194,326	2,177,956
Common stock, shares outstanding	1,639,600	1,289,342
Common stock voting rights	one
Number of director entitled to elect by common stock holders \| Director	1

Common Stock - Common Stock Reserved for Issuance Upon Conversion of Outstanding Convertible Preferred Stock and Exercise of Stock Options (Details)	Sep. 30, 2021 shares
Schedule Of Common Stock Reserved For Future Issuance [Line Items]
Common stock reserved for future issuance	28,418,977
Series A Convertible Preferred Stock
Schedule Of Common Stock Reserved For Future Issuance [Line Items]
Common stock reserved for future issuance	3,573,659
Series B Convertible Preferred Stock
Schedule Of Common Stock Reserved For Future Issuance [Line Items]
Common stock reserved for future issuance	16,482,486
Unvested Restricted Stock Options
Schedule Of Common Stock Reserved For Future Issuance [Line Items]
Common stock reserved for future issuance	554,724
Stock Options Available for Issuance
Schedule Of Common Stock Reserved For Future Issuance [Line Items]
Common stock reserved for future issuance	3,852,807
Stock Options Outstanding
Schedule Of Common Stock Reserved For Future Issuance [Line Items]
Common stock reserved for future issuance	3,530,706
Employee Stock Purchase Plan
Schedule Of Common Stock Reserved For Future Issuance [Line Items]
Common stock reserved for future issuance	424,595

Stock-Based Compensation - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2019	Sep. 27, 2021
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of common shares reserved for future issuance	28,418,977		28,418,977
Fair value of common stock per share	$ 16		$ 16
Weighted-average fair value of options granted	$ 5.59	$ 0.04	$ 4.15	$ 0.04
Gross unrecognized stock-based compensation expense	$ 10,800		$ 10,800
Unrecognized stock-based compensation expense weighted average amortized period			2 years 10 months 2 days
Number of restricted common stock shares issued					994,650
Stock-based compensation expense	$ 307	$ 12	$ 3,329	$ 29
Restricted Stock Awards
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of common shares reserved for future issuance	554,724		554,724
Unrecognized stock-based compensation expense weighted average amortized period			1 year 8 months 12 days
Common stock public offering price per share					$ 0.01
Stock-based compensation expense	$ 5	$ 6	$ 17	$ 17
Gross unrecognized stock-based compensation expense	$ 30		$ 30
2021 Equity Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of common shares reserved for future issuance						3,852,807
2019 Equity Incentive Plan \| Maximum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of common shares reserved for future issuance	4,042,408		4,042,408
2021 Employee Stock Purchase Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of common shares authorized for issuance	424,595		424,595
Number of shares issued			0
2021 Employee Stock Purchase Plan \| Maximum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of common shares reserved for future issuance	424,595		424,595

Stock-Based Compensation - Summary of Stock Option Activity (Details) $ / shares in Units, $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2021 USD ($) $ / shares shares	Dec. 31, 2020 USD ($) $ / shares shares
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Number of Shares, Outstanding, Beginning Balance \| shares	220,383
Number of Shares, Granted \| shares	3,672,351
Number of Shares, Exercised \| shares	(16,370)
Number of Shares, Forfeited \| shares	(345,658)
Number of Shares, Outstanding, Ending Balance \| shares	3,530,706	220,383
Number of Shares, Exercisable at September 30, 2021 \| shares	927,403
Weighted Average Exercise Price, Beginning Balance \| $ / shares	$ 0.64
Weighted Average Exercise Price, Granted \| $ / shares	6.38
Weighted Average Exercise Price, Exercised \| $ / shares	0.88
Weighted Average Exercise Price, Forfeited \| $ / shares	5.29
Weighted Average Exercise Price, Ending Balance \| $ / shares	6.16	$ 0.64
Weighted Average Exercise Price, Exercisable at September 30, 2021 \| $ / shares	$ 4.89
Weighted Average Remaining Contractual Term, Outstanding	9 years 8 months 12 days	9 years 4 months 24 days
Weighted Average Remaining Contractual Term, Granted	9 years 7 months 6 days
Weighted Average Remaining Contractual Term, Exercisable	9 years 7 months 6 days
Aggregate Intrinsic Value, Outstanding \| $	$ 34,755	$ 348
Aggregate Intrinsic Value, Exercisable \| $	$ 10,304

Stock-Based Compensation - Schedule of Estimated Fair Value Assumptions (Details)	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected volatility, minimum	72.88%	87.40%	72.88%	82.80%
Expected volatility, maximum	73.13%	87.40%	75.17%	87.40%
Risk-free interest rate, minimum	0.81%	0.38%	0.81%	0.38%
Risk-free interest rate, maximum	0.96%	0.38%	1.16%	0.56%
Expected dividend yield	0.00%	0.00%	0.00%	0.00%
Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected term (in years)	6 years 29 days	6 years 29 days	6 years 29 days	6 years 29 days
Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected term (in years)	6 years	6 years 7 days	6 years	6 years 7 days

Stock-Based Compensation - Summary of Stock-Based Compensation Expense (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation expense	$ 307	$ 12	$ 3,329	$ 29
Research and Development
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation expense	96	4	1,106	10
General and Administrative
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation expense	$ 211	$ 8	$ 2,223	$ 19

Stock-Based Compensation - Summary of Restricted Stock Activity (Details)	9 Months Ended
	Sep. 30, 2021 shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of Shares, Outstanding, Beginning Balance	888,612
Number of Shares, Vested	(333,888)
Number of Shares, Exercisable at September 30, 2021	554,724

Income Taxes - Additional Information (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Income Tax Disclosure [Abstract]
Effective tax rate from continuing operations	0.00%	0.00%	0.00%	0.00%
Federal income tax provision			$ 0	$ 0
State and local income tax provision				$ 0

Net Loss per Common Share - Summary of Basic and Diluted Net Loss Per Common Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2021	Sep. 30, 2020
Numerator:
Net loss	$ (14,175)	$ (8,003)	$ (36,968)	$ (3,191)	$ (3,100)	$ (1,958)	$ (59,146)	$ (8,249)
Denominator:
Weighted-average common shares outstanding, basic and diluted	1,581,610			1,088,222			1,468,777	979,081
Net loss per common share, basic and diluted	$ (8.96)			$ (2.93)			$ (40.27)	$ (8.43)

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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+ Details

Net Loss per Common Share - Anti-Dilutive Effect Excluded from Computation of Diluted Net Loss Per Share Attributable to Common Stockholders (Details) - shares	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Anti-dilutive effect excluded from computation of diluted net loss per share attributable to common stockholders	28,418,977	4,874,307
Convertible Preferred Stock
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Anti-dilutive effect excluded from computation of diluted net loss per share attributable to common stockholders	20,056,145	3,573,659
Unvested Restricted Stock
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Anti-dilutive effect excluded from computation of diluted net loss per share attributable to common stockholders	554,724	1,044,516
Stock Options Outstanding
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Anti-dilutive effect excluded from computation of diluted net loss per share attributable to common stockholders	3,530,706	168,296
Stock Options Available for Issuance
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Anti-dilutive effect excluded from computation of diluted net loss per share attributable to common stockholders	3,852,807	87,836
Employee Stock Purchase Plan
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Anti-dilutive effect excluded from computation of diluted net loss per share attributable to common stockholders	424,595

Related Parties - Additional Information (Details) - USD ($)	1 Months Ended				3 Months Ended			9 Months Ended		12 Months Ended
	Apr. 30, 2021	Mar. 31, 2021	Dec. 31, 2020	Apr. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Jun. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Related Party Transaction [Line Items]
Research and development expense					$ 7,849,000	$ 2,425,000		$ 43,828,000	$ 5,909,000
Proceeds from the exercise of stock options								14,000	31,000
Pfizer License Agreement
Related Party Transaction [Line Items]
Research and development expense					0			25,000,000.0
Upfront payments								5,000,000.0
LegoChem License Agreement
Related Party Transaction [Line Items]
Research and development expense								9,000,000.0
Payments to purchase licensed products		$ 9,000,000.0	$ 500,000					$ 9,000,000.0
Settlement on outstanding liability		$ 500,000
Proceeds from the exercise of stock options	$ 8,000,000.0			$ 8,000,000.0
Milestone payment upon certain events occur	$ 9,600,000
Common Stock
Related Party Transaction [Line Items]
Stock issued							48,919
Series B Convertible Preferred Stock \| Pfizer License Agreement
Related Party Transaction [Line Items]
Issuance of convertible preferred stock shares								12,152,145
Issuance of convertible preferred stock value					20,000,000.0			$ 20,000,000.0
Series B Convertible Preferred Stock \| LegoChem License Agreement
Related Party Transaction [Line Items]
Issuance of convertible preferred stock shares		303,804
University License Agreement
Related Party Transaction [Line Items]
Stock issued				311,076
Stock issued, shares, reverse stock splits				48,919
Research and development expense					0			0	3,000
University License Agreement \| Common Stock
Related Party Transaction [Line Items]
Stock issued				311,076
Stock issued, shares, reverse stock splits				48,919
University License Agreement \| Series A Preferred Stock
Related Party Transaction [Line Items]
Stock issued										309,885
Scientific Advisory Board
Related Party Transaction [Line Items]
Maximum amount paid to board members					100,000	100,000		100,000	100,000
Aggregate maximum amount paid to related parties					$ 100,000	$ 100,000		$ 100,000	$ 100,000
Minimum \| Scientific Advisory Board
Related Party Transaction [Line Items]
Payments to board members per month										$ 3,000
Maximum \| Scientific Advisory Board
Related Party Transaction [Line Items]
Payments to board members per month										$ 5,000

Commitment and Contingencies - Additional Information (Details) $ in Millions		3 Months Ended		9 Months Ended
	Sep. 29, 2021 USD ($)	Sep. 30, 2021 USD ($) Lease	Sep. 30, 2020 USD ($)	Sep. 30, 2021 USD ($) Lease	Sep. 30, 2020 USD ($)
Commitments And Contingencies Disclosure [Abstract]
Number of operating lease \| Lease		2		2
Operating lease terms expiration year				2022
Number of finance lease \| Lease		0		0
Operating lease, rent expense \| $		$ 0.2	$ 0.2	$ 0.5	$ 0.5
Future minimum lease obligations \| $	$ 33.8	$ 0.3		$ 0.3
Lease expiration date	Dec. 31, 2032
Rent increase percentage	3.00%
Operating lease, option to extend				There is an additional five-year option to extend the lease beyond December 31, 2032.
Operating lease option to extend [true false]	true
Operating lease, renewal term	5 years
Operating lease, term of contract	10 years