0001725160-21-000075 | 10-K | XBRL Viewer | Zentalis Pharmaceuticals INC

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Cover - USD ($) $ in Millions	12 Months Ended
Cover - USD ($) $ in Millions	Dec. 31, 2020	Mar. 24, 2021	Jun. 30, 2020
Cover [Abstract]
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2020
Document Transition Report	false
Entity File Number	001-39263
Entity Registrant Name	Zentalis Pharmaceuticals, Inc.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	82-3607803
Entity Address, Address Line One	530 Seventh Avenue
Entity Address, Address Line Two	Suite 2201
Entity Address, City or Town	New York
Entity Address, State or Province	NY
Entity Address, Postal Zip Code	10018
City Area Code	212
Local Phone Number	433-3791
Title of 12(b) Security	Common stock,$0.001 par value per share
Trading Symbol	ZNTL
Security Exchange Name	NASDAQ
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
Entity Shell Company	false
Entity Public Float			$ 1,150
Entity Common Stock, Shares Outstanding (in shares)		41,040,286
Documents Incorporated by Reference	Portions of the registrant's definitive Proxy Statement relating to its 2021 Annual Meeting of Stockholders to be filed with the SEC within 120 days after the end of the fiscal year ended December 31, 2020 are incorporated herein by reference in Part III.
Entity Central Index Key	0001725160
Amendment Flag	false
Document Fiscal Period Focus	FY
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2020

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Current assets
Cash and cash equivalents	$ 54,951	$ 67,246
Marketable securities, available for sale	283,554	0
Accounts receivable from government grants, net	417	140
Prepaid expenses and other current assets	6,182	1,505
Total current assets	345,104	68,891
Property and equipment, net	1,099	501
Operating lease right-of-use assets	2,520	2,335
Prepaid expenses and other assets	2,976	2,134
Deferred financing costs	0	841
Goodwill	3,736	3,736
In-process research and development	8,800	8,800
Restricted cash	1,320	243
Total assets	365,555	87,481
Current Liabilities
Accounts payable	8,661	4,289
Accrued expenses	19,940	10,608
Total current liabilities	28,601	14,897
Deferred tax liability	2,480	2,463
Other long-term liabilities	1,097	1,700
Total liabilities	32,178	19,060
Commitments and contingencies
Convertible preferred units		141,706
EQUITY
Preferred stock, value	0
Common Stock, value	41
Additional paid-in capital	509,339
Accumulated other comprehensive income	36
Accumulated deficit	(200,834)	(82,993)
Total stockholders' equity/members' (deficit)	308,582	(80,106)
Noncontrolling interests	24,795	6,821
Total equity (deficit)	333,377	(73,285)
Total liabilities, convertible preferred units and equity (deficit)	$ 365,555	87,481
Class A Common Units
EQUITY
Class A and B common units, issuance value		709
Class B Common Units
EQUITY
Class A and B common units, issuance value		$ 2,178

Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Convertible preferred units, redemption value		$ 146,944
Preferred stock, par value (in dollars per share)	$ 0.001
Preferred stock, shares authorized (in shares)	10,000,000
Preferred stock, shares issued (in shares)	0
Preferred stock, shares outstanding (in shares)	0
Common stock, par value (in dollars per share)	$ 0.001
Common stock, shares authorized (in shares)	250,000,000
Common stock issued (in shares)	41,040,286
Common stock outstanding (in shares)	41,040,286
Class A Common Units
Common units, authorized (in shares)		20,000,000
Common units, issued (in shares)		5,601,478
Common units, outstanding (in shares)		5,601,478
Class B Common Units
Common units, authorized (in shares)		3,458,522
Common units, issued (in shares)		2,670,668
Common units, outstanding (in shares)		2,670,668

Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019
Operating Expenses
Research and development	$ 29,521	$ 24,670	$ 17,452	$ 13,258	$ 11,869	$ 10,739	$ 8,689	$ 7,089	$ 84,901	$ 38,386
General and administrative	10,724	10,097	9,924	3,141	3,036	1,844	1,946	1,633	33,886	8,459
Total operating expenses	40,245	34,767	27,376	16,399	14,905	12,583	10,635	8,722	118,787	46,845
Operating loss	(40,245)	(34,767)	(27,376)	(16,399)	(14,905)	(12,583)	(10,635)	(8,722)	(118,787)	(46,845)
Other Income (Expense)
Investment and other income (expense), net	315	120	84	164	359	12	49	62	683	482
Net loss before income taxes	(39,930)	(34,647)	(27,292)	(16,235)	(14,546)	(12,571)	(10,586)	(8,660)	(118,104)	(46,363)
Income tax expense	426	18	0	0	0	1	11	3	444	15
Net loss	(40,356)	(34,665)	(27,292)	(16,235)	(14,546)	(12,572)	(10,597)	(8,663)	(118,548)	(46,378)
Net loss attributable to noncontrolling interests	(53)	(110)	(435)	(109)	(40)	(228)	(127)	(320)	(707)	(715)
Net loss attributable to Zentalis	$ (40,303)	$ (34,555)	$ (26,857)	$ (16,126)	$ (14,506)	$ (12,344)	$ (10,470)	$ (8,343)	$ (117,841)	$ (45,663)
Common shares/units used in computing net loss per share/Class A common unit, basic and diluted (in shares)	39,936	37,959	34,353	5,601					28,113	5,597
Common Stock
Other Income (Expense)
Net loss per share/unit outstanding, basic and diluted (USD per share)	$ (1.01)	$ (0.91)	$ (0.78)		$ (2.59)	$ (2.20)	$ (1.87)	$ (1.49)	$ (4.19)	$ 0
Class A Common Units
Other Income (Expense)
Net loss per share/unit outstanding, basic and diluted (USD per share)				$ (2.88)	$ 5,601,000	$ 5,599,000	$ 5,594,000	$ 5,594,000	$ 0	$ (8.16)

Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Statement of Comprehensive Income [Abstract]
Net loss	$ (118,548)	$ (46,378)
Other comprehensive income:
Unrealized gain on marketable securities, net	36	0
Total comprehensive loss	(118,512)	(46,378)
Comprehensive loss attributable to noncontrolling interests	(707)	(715)
Comprehensive loss attributable to Zentalis	$ (117,805)	$ (45,663)

- Definition

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income (loss) and other comprehensive income (loss), attributable to noncontrolling interests. Excludes changes in equity resulting from investments by owners and distributions to owners.

+ References + Details

- Definition

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income. Excludes changes in equity resulting from investments by owners and distributions to owners.

+ References + Details

- Definition

The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

+ References

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+ Details

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Operating activities:
Consolidated net loss	$ (118,548)	$ (46,378)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	160	111
Share-based compensation	23,146	617
Amortization of premiums on marketable securities, net	556	0
Deferred income taxes	17	0
Changes in operating assets and liabilities:
Accounts receivable	(277)	777
Prepaid expenses and other assets	(5,519)	(1,508)
Accounts payable and accrued liabilities	14,307	7,123
Operating lease right-of-use assets and liabilities, net	(667)	115
Net cash used in operating activities	(86,825)	(39,143)
Investing activities:
Purchases of marketable securities	(400,984)	0
Proceeds from maturities of marketable securities	116,910	0
Purchases of property and equipment	(758)	(352)
Net cash used in investing activities	(284,832)	(352)
Financing activities:
Proceeds from issuance of common stock in initial public offering, net	172,482	0
Contributions from noncontrolling interest owners, net	18,424	0
Proceeds from the issuance of Series C convertible preferred units, net	14,228	81,876
Proceeds from issuance of common stock, net	155,305	0
Deferred financing costs	0	(46)
Net cash provided by financing activities	360,439	81,830
Increase/(decrease) in cash, cash equivalents and restricted cash	(11,218)	42,335
Cash, cash equivalents and restricted cash at beginning of year	67,489	25,154
Cash, cash equivalents and restricted cash at end of year	56,271	67,489
Supplemental disclosure of cash flow information:
Income taxes paid	18	15
Supplemental disclosure of non-cash investing and financing activities:
Right-of-use assets obtained in exchange for operating lease liabilities	300	1,412
Costs incurred in connection with initial public offering included in accounts payable and accrued expenses	0	795
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents
Total cash, cash equivalents and restricted cash reported in the Consolidated Statement of Cash Flows	$ 56,271	$ 25,154

Consolidated Statements of Changes in Convertible Preferred Units and Members’/Stockholders' Equity (Deficit) - USD ($) $ in Thousands	Total	IPO	Convertible Preferred Units	Class A Common Units	Class B Common Units	Series C Preferred Units	Preferred Stock Convertible Preferred Units	Common Stock	Common Stock IPO	Common Stock Class A Common Units	Common Stock Class B Common Units	Additional Paid-In Capital	Additional Paid-In Capital IPO	Accumulated Other Comprehensive Income	Accumulated Deficit	Noncontrolling Interests
Temporary equity beginning balance (in shares) at Dec. 31, 2018			0
Temporary equity, beginning balance at Dec. 31, 2018			$ 0
Increase (Decrease) in Temporary Equity [Roll Forward]
Issuance of Series C convertible preferred units at $17.50 per unit net of issuance costs (in shares)			4,847,000
Issuance of Series C convertible preferred units at $17.50 per unit net of issuance costs			$ 81,876
Reclassification of convertible preferred units for contingent liquidation features not within the Company's control (in shares)			5,103,000
Reclassification of convertible preferred units for contingent liquidation features not within the Company's control			$ 59,830
Temporary equity ending balance (in shares) at Dec. 31, 2019	9,950,154,000		9,950,000			4,847,106,000
Temporary equity, ending balance at Dec. 31, 2019	$ 141,706		$ 141,706			$ 81,876
Beginning balance (in shares) at Dec. 31, 2018							5,103,000	0
Beginning balance at Dec. 31, 2018	32,306						$ 59,830	$ 0				$ 0		$ 0	$ (37,330)	$ 7,536
Common units, beginning balance (in shares) at Dec. 31, 2018										5,594,000	1,612,000
Common units, beginning balance at Dec. 31, 2018										$ 672	$ 1,598
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock issued (in shares)				7,093							1,059,000
Reclassification of convertible preferred units for contingent liquidation features not within the Company's control (in shares)							(5,103,000)
Reclassification of convertible preferred units for contingent liquidation features not within the Company's control	(59,830)						$ (59,830)
Share-based compensation expenses (in shares)										7,000
Share-based compensation expenses	617									$ 37	$ 580
Net loss attributable to noncontrolling interests	(715)															(715)
Net loss attributable to Zentalis	(45,663)														(45,663)
Ending balance (in shares) at Dec. 31, 2019							0	0
Ending balance at Dec. 31, 2019	(73,285)						$ 0	$ 0				0		0	(82,993)	6,821
Common units, ending balance (in shares) at Dec. 31, 2019				5,601,478	2,670,668					5,601,000	2,671,000
Common units, ending balance at Dec. 31, 2019				$ 709	$ 2,178					$ 709	$ 2,178
Increase (Decrease) in Temporary Equity [Roll Forward]
Issuance of Series C convertible preferred units at $17.50 per unit net of issuance costs (in shares)			867,000
Issuance of Series C convertible preferred units at $17.50 per unit net of issuance costs			$ 14,228
Conversion of convertible preferred units to common stock (in shares)			(10,817,000)					(15,011,000)
Conversion of convertible preferred units to common stock	155,934		$ (155,934)					$ 15				155,919
Temporary equity ending balance (in shares) at Dec. 31, 2020			0
Temporary equity, ending balance at Dec. 31, 2020			$ 0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cancellation of profit interest awards, net (shares)											(64,000)
Stock issued (in shares)				0				4,744,000	10,589,000
Stock issued, value	155,305	$ 172,365						$ 5	$ 11			155,300	$ 172,354
Contributions from noncontrolling interest owners	18,424															18,424
Conversion of convertible preferred units to common stock (in shares)			10,817,000					15,011,000
Conversion of convertible preferred units to common stock	155,934		$ (155,934)					$ 15				155,919
Conversion of common and incentive units to common stock (in shares)								(10,278,000)		(5,601,000)	(2,607,000)
Conversion of common and incentive units to common and restricted stock	0							$ 10		$ (709)	$ (2,507)	3,206
Cancellation of restricted stock awards (in shares)								(8,000)
Share-based compensation expenses	23,146										$ 329	22,817
Issuance of common stock in connection with restricted stock unit vesting (in shares)								426,000
Other comprehensive income	36													36
Net loss attributable to noncontrolling interests	(707)											(257)				(450)
Net loss attributable to Zentalis	(117,841)														(117,841)
Ending balance (in shares) at Dec. 31, 2020							0	41,040,000
Ending balance at Dec. 31, 2020	$ 333,377						$ 0	$ 41				$ 509,339		$ 36	$ (200,834)	$ 24,795
Common units, ending balance (in shares) at Dec. 31, 2020										0	0
Common units, ending balance at Dec. 31, 2020										$ 0	$ 0

Consolidated Statements of Changes in Convertible Preferred Units and Members’/Stockholders' Equity (Deficit) (Parenthetical)) - $ / shares	Dec. 31, 2020	Feb. 29, 2020	Dec. 31, 2019	Sep. 30, 2019
Series C Preferred Units
Par value per share (in dollars per share)	$ 17.50	$ 17.50	$ 17.50	$ 17.50

Organization and Business	12 Months Ended
Organization and Business	Dec. 31, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization and Business	Organization and Business Organization Zentalis Pharmaceuticals, Inc. (successor to Zentalis Pharmaceuticals, LLC (“Zentalis”, “We” or “the Company”) is a clinical-stage pharmaceutical company focused on discovering and developing clinically differentiated, novel small molecule therapeutics targeting fundamental biological pathways of cancer. The Company manages its operations as a single segment for the purposes of assessing performance and making operating decisions. To date, all of the Company's revenue has been generated in the United States. All of the Company's material tangible assets are held in the United States. The Company was formed and incorporated in the state of Delaware as Zeno Pharmaceuticals, Inc. on December 23, 2014. Effective November 21, 2017, Zeno Pharma, LLC was formed by the shareholders of Zeno Pharmaceuticals, Inc. On December 21, 2017, Zeno Pharmaceuticals, Inc. became a wholly owned subsidiary of Zeno Pharma, LLC. In connection with this restructuring, the rights and preferences of the Preferred Stock of Zeno Pharmaceuticals, Inc. were exchanged for preferred units with similar rights and preferences of Zeno Pharma, LLC. As part of the restructuring, the employees, consultants and board members of Zeno Pharmaceuticals, Inc. exchanged their equity grants in Zeno Pharmaceuticals, Inc. stock for Class B common units in Zeno Pharma, LLC. Additionally, existing common stockholders of Zeno Pharmaceuticals, Inc. exchanged their common stock for Class A common units in Zeno Pharma, LLC. All exchanges were made on a one-for-one basis. The restructuring was accounted for as a common control transaction. In December 2019, the Company was renamed to Zentalis Pharmaceuticals, LLC. See note 9, Equity and Share-based Compensation, for additional information. Immediately prior to the effectiveness of the registration statement pertaining to the Company's initial public offering ("IPO") on April 2, 2020, the Company converted from a Delaware limited liability company into a Delaware corporation, and changed its name to Zentalis Pharmaceuticals, Inc. Pursuant to the statutory corporate conversion, all of the outstanding units of Zentalis Pharmaceuticals, LLC converted into shares of common stock of Zentalis Pharmaceuticals, Inc. based upon the value of Zentalis Pharmaceuticals, Inc. at the time of the IPO with a value implied by the price of the shares of common stock sold in the IPO. Based on the IPO price of $18.00 per share, the outstanding converted units converted into 25,288,854 shares of common stock (including 1,160,277 shares of restricted common stock). On April 7, 2020, the Company completed the IPO in which the Company issued and sold 10,557,000 shares of common stock (including 1,377,000 shares of common stock in connection with the full exercise of the underwriters' option to purchase additional shares) at a public offering price of $18.00 per share. The Company's aggregate gross proceeds from the sale of shares in the IPO, including the sale of shares pursuant to the full exercise of the underwriters' option to purchase additional shares, was $190.0 million before fees and expenses of $17.6 million. On May 19, 2020, the Company announced the closing of a Series A financing of Zentera Therapeutics, Ltd. ("Zentera"), a majority owned biopharmaceutical company with headquarters in Shanghai, China. Contributions from noncontrolling interest members totaled $20.0 million before issuance costs of $1.6 million. The Company holds 60.2% equity interest in Zentera for purposes of the development and commercialization of ZN-c5, ZN-d5 and ZN-c3 for the treatment or prevention of disease, other than for pain, in the People's Republic of China, Macau, Hong Kong and Taiwan. Two of our executives entered into restricted stock purchase agreements with Zentera. The associated shares vest over four years. On August 3, 2020, the Company completed a follow-on offering in which the Company issued and sold 4,743,750 shares of common stock (including 618,750 shares of common stock in connection with the full exercise of the underwriters' option to purchase additional shares) at a public offering price of $35.00 per share. The Company's aggregate gross proceeds from the sale of shares in the follow-on offering, including the sale of shares pursuant to the full exercise of the underwriters' option to purchase additional shares, was $166.0 million before fees and expenses of $10.8 million.

Summary of Significant Accounting Policies

12 Months Ended

Dec. 31, 2020

Accounting Policies [Abstract]

Summary of Significant Accounting Policies

Basis of Presentation

The consolidated financial statements have been prepared in conformity with U.S. generally accepted accounting principles (“U.S. GAAP”) and include our wholly owned subsidiaries, majority-owned or controlled companies, and variable interest entity (“VIE”), Kalyra Pharmaceuticals, Inc. (“Kalyra”), for which we are the primary beneficiary. All intercompany transactions and balances have been eliminated in consolidation.

We evaluate our ownership, contractual and other interests in entities that are not wholly-owned to determine if these entities are VIEs, and, if so, whether we are the primary beneficiary of the VIE. In determining whether we are the primary beneficiary of a VIE and therefore required to consolidate the VIE, we apply a qualitative approach that determines whether we have both (1) the power to direct the activities of the VIE that most significantly impact the VIE’s economic performance and (2) the obligation to absorb losses of, or the rights to receive benefits from, the VIE that could potentially be significant to that VIE. On December 21, 2017, the Company acquired a 25% equity interest in Kalyra. Based on our assessment, we concluded that Kalyra is a variable interest entity and we are the primary beneficiary. Prior to the acquisition, Zeno and Kalyra transacted for the delivery of research and development services and support. The financial position and results of operations of Kalyra have been included in the Company’s consolidated financial statements from December 21, 2017, the date we became the primary beneficiary. The liabilities recognized as a result of consolidating Kalyra do not represent additional claims on the Company’s general assets.

We will continuously assess whether we are the primary beneficiary of a VIE, as changes to existing relationships or future transactions may result in the consolidation or deconsolidation of such VIE. During the periods presented, we have not provided any other financial or other support to our VIE that we were not contractually required to provide.

Noncontrolling Interests

The shares third parties own in Kalyra and Zentera represent an interest in their respective equity we do not control. We reflect noncontrolling interest attributable to the other owners in a separate line in our consolidated statements of operations and a separate line within stockholders' equity in our consolidated balance sheets. In addition, we record a noncontrolling interest adjustment to account for equity based compensation in Zentera. This adjustment is a reclassification within stockholders' equity from additional paid-in capital to noncontrolling interest equal to the amount of equity based compensation expense Zentera had recognized.

Use of Estimates

The preparation of consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the amounts reported in our consolidated financial statements and accompanying notes. On an ongoing basis, we evaluate our estimates and judgments, which are based on historical and anticipated results and trends and on various other assumptions that management believes to be reasonable under the circumstances. By their nature, estimates are subject to an inherent degree of uncertainty and, as such, actual results may differ from management’s estimates.

Though the impact of the COVID-19 pandemic to our business and operating results presents additional uncertainty, we continue to use the best information available to inform our critical accounting estimates.

Cash and Cash Equivalents

Cash equivalents are comprised of short-term, highly-liquid investments with maturities of 90 days or less at the date of purchase. As of December 31, 2020 and 2019, our cash equivalents consisted of money market funds and corporate debt securities.

Marketable Securities

Marketable securities are investments with original maturities of more than ninety days from the date of purchase that we have the ability to liquidate to find current operations. Accordingly, those investments with contractual maturities greater than one year from the date of purchase are classified as short-term investments on the accompanying consolidated balance sheets. Marketable securities are considered available-for-sale and are carried at fair value with unrealized gains and losses recorded in other comprehensive income (loss) and included as a separate component of stockholders' equity. The cost of marketable securities is adjusted for amortization of premiums or accretion of discounts to maturity, and such amortization or accretion is included in investment and other income, net through an allowance account. We use the specific identification method for calculating realized gains and losses on marketable securities sold. Realized gains and losses on marketable securities, if any, are included in investment and other income, net in the consolidated statements of operations.

Restricted Cash

Under the terms of our office leases, we are required to maintain a letter of credit as a security deposit during the term of such leases. At December 31, 2020 and 2019, restricted cash of $1.3 million and $0.2 million, respectively, was pledged as collateral for the letters of credit.

Fair Value of Financial Instruments

The authoritative guidance defines fair value and requires us to establish a framework for measuring fair value and disclosure about fair value measurements using a three-tier approach. These tiers include: Level 1, defined as observable inputs such as quoted prices in active markets; Level 2, defined as inputs other than quoted prices in active markets that are either directly or indirectly observable; and Level 3, defined as unobservable inputs in which little or no market data exists, therefore requiring an entity to develop its own assumptions.

Our financial instruments include cash equivalents, marketable securities, accounts receivable, prepaid expenses and other assets, accounts payable and accrued expenses. Fair value estimates of these instruments are made at a specific point in time, based on relevant market information. These estimates may be subjective in nature and involve uncertainties and matters of significant judgement and therefore cannot be determined with precision.

The fair value of marketable securities is determined using proprietary valuation models and analytical tools, which utilize market pricing or prices for similar instruments that are both objective and publicly available, such as matrix pricing or reported trades, benchmark yields, broker/dealer quotes, issuer spreads, two-sided markets, benchmark securities and bids and offers.

The carrying amount of cash equivalents, account receivable, prepaid expenses and other assets, accounts payable and accrued expenses are generally considered to be representative of their respective values because of the short-term nature of those instruments.

Concentrations of Credit Risk and Sources of Supply

We are subject to credit risk from our portfolios of cash equivalents and marketable securities. We maintain our cash and cash equivalent and marketable securities balances with major commercial banks. Deposits held with the financial institutions exceed the amount of insurance provided on such deposits. We are exposed to credit risk in the event of a default by the financial institutions holding our cash and cash equivalents and marketable securities to the extent recorded on the consolidated balance sheets.We have also established guidelines to limit our exposure to credit risk by diversifying our marketable securities portfolio and placing them in investments with maturities that maintain safety and liquidity.

We rely on third-party manufacturers for the supply of active pharmaceutical ingredients.

Accounts Receivable from Government Grants, Net

Accounts receivable from government grants is recorded at the invoiced amount, is non-interest bearing and is recorded net of allowances for doubtful accounts. We recorded no allowance for doubtful accounts at December 31, 2020 and 2019 as the collectability was reasonably assured.

Property and Equipment, Net

Property and equipment are recorded at cost, less accumulated depreciation and amortization. Equipment is depreciated using the straight-line method over its estimated useful life ranging from three to five years and leasehold improvements are amortized using the straight-line method over the estimated useful life of the asset or the lease term, whichever is shorter. Repair and maintenance costs are expensed as incurred.

Leases

We have entered into operating leases for real estate. We determine if an arrangement is a lease at inception and evaluate each lease agreement to determine whether the lease is an operating or finance lease. For leases where we are the lessee, right-of-use (“ROU”) assets represent the Company’s right to use an underlying asset for the lease term and lease liabilities represent an obligation to make lease payments arising from the lease. Liabilities from operating leases are included in accrued expenses and other long-term liabilities on our consolidated balance sheet. ROU assets and lease liabilities are recognized at the lease commencement date based on the present value of lease payments over the lease term. As our leases do not provide an implicit interest rate, we use our incremental borrowing rate based on the information available at the commencement date in determining the present value of lease payments. The operating lease ROU asset also includes any prepaid lease payments, lease incentives received, and costs which will be incurred in exiting a lease. Our leases often include options to extend or terminate the lease. These options are included in the lease term when it is reasonably certain that we will exercise that option. As of December 31, 2020 it is not reasonably certain that these options will be exercised and they are not included within the

lease term. Short-term leases with an initial term of 12 months or less are not recorded on the balance sheet. Lease expense for minimum lease payments is recognized on a straight-line basis over the lease term. We have lease agreements with lease and non-lease components which are accounted for as a single lease component for all of our leases.

Impairment of Long-Lived Assets

We account for long-lived assets in accordance with authoritative guidance for impairment or disposal of long-lived assets. Long-lived assets are reviewed for events or changes in circumstances, which indicate that their carrying value may not be recoverable. To date, we have not experienced any significant impairment losses.

Goodwill and In-Process Research and Development

Our goodwill, which has an indefinite useful life, represents the excess of the cost over the fair value of net assets acquired from its business combination. The determination of the value of goodwill and intangible assets arising from business combinations and asset acquisitions requires extensive use of accounting estimates and judgments to allocate the purchase price to the fair value of the net tangible and intangible assets acquired, including capitalized in-process research and development (“IPR&D”).

Intangible assets acquired in a business combination that are used for IPR&D activities are considered indefinite lived until the completion or abandonment of the associated research and development efforts. Upon conclusion of the relevant research and development project, we will amortize the acquired IPR&D over its estimated useful life or expense the acquired IPR&D should the research and development project be unsuccessful with no future alternative use. We base the useful lives and related amortization expense on our estimate of the period that the assets will generate revenues or otherwise be used. We assess the carrying value of our IPR&D assets at least annually, or more frequently if an event occurs indicating the potential for impairment, which requires us to make assumptions and judgements regarding the future cash flows of these assets. If the assets are considered to be impaired, the impairment we recognize is the amount by which the carrying value of the assets exceeds the fair value of the assets. Fair value is determined by a combination of third-party sources and forecasted discounted cash flows.

Goodwill is reviewed for impairment at least annually, or more frequently if an event occurs indicating the potential for impairment. During the impairment review process, we consider qualitative factors to determine whether it is more likely than not that the fair value of the reporting unit is less than the carrying amount, including goodwill. If we determine that it is not more likely than not that the fair value of our reporting unit is less than the carrying amount, then no additional assessment is deemed necessary. Otherwise, we proceed to compare the estimated fair values of the reporting units with the carrying values, including goodwill. If the carrying amounts of the reporting units exceed the fair values, we record an impairment loss based on the difference. We completed our most recent annual evaluation for impairment for goodwill and IPR&D as of December 31, 2020 using the qualitative assessment and determined that no impairment existed, and no charges were recorded.

Research and Development Expenses

Research and development expenses include salaries and benefits, facilities and other overhead expenses, external clinical trial expenses, research related manufacturing services, contract services and other outside expenses. Research and development expenses are charged to operating expenses as incurred when these expenditures relate to our research and development efforts and have no alternative future uses. Reimbursed research and development costs under government grant arrangements are recorded as a reduction to research and development expenses and are recognized in the period in which the related costs are incurred.

We are obligated to make upfront payments upon execution of certain research and development agreements. Advance payments, including nonrefundable amounts, for goods or services that will be used or rendered for future research and development activities are deferred. Such amounts are recognized as expense as the related goods are delivered or the related services are performed, or such time when we do not expect the goods to be delivered or services to be performed.

Clinical Trial Expenses

We make payments in connection with our clinical trials under contracts with contract research organizations that support conducting and managing clinical trials. The financial terms of these agreements are subject to negotiation and vary from contract to contract and may result in uneven payment flows. Generally, these agreements set forth the scope of work to be performed at a fixed fee, unit price or on a time and materials basis. A portion of our obligation to make payments under these

contracts depends on factors such as the successful enrollment or treatment of patients or the completion of other clinical trial milestones.

Expenses related to clinical trials are accrued based on our estimates and/or representations from service providers regarding work performed, including actual level of patient enrollment, completion of patient studies and progress of the clinical trials. Other incidental costs related to patient enrollment or treatment are accrued when reasonably certain. If the amounts we are obligated to pay under our clinical trial agreements are modified (for instance, as a result of changes in the clinical trial protocol or scope of work to be performed), we adjust our accruals accordingly. Revisions to our contractual payment obligations are charged to expense in the period in which the facts that give rise to the revision become reasonably certain.

Share-Based Compensation

We record share-based compensation expense associated with equity instruments in accordance with the authoritative guidance for stock-based compensation. The cost of employee services received in exchange for an award of an equity instrument is measured at the grant date based on the estimated fair value of the award and is recognized as expense on a straight-line basis over the requisite service period of the award. Share-based compensation expense for an award with a performance condition is recognized when the achievement of such performance condition is determined to be probable. If the outcome of such performance condition is not determined to be probable or is not met, no compensation expense is recognized, and any previously recognized compensation expense is reversed. Forfeitures are recognized as a reduction of share-based compensation expense as they occur.

Income Taxes

Deferred income taxes are recognized for the tax consequences in future years of differences between the tax basis of assets and liabilities and their financial reporting amounts at each year end based on enacted tax laws and statutory tax rates applicable to the periods in which the differences are expected to affect taxable income. A provision has been made for income taxes due on taxable income and for the deferred taxes on temporary differences. Deferred tax assets and liabilities are adjusted for the effects of changes in tax laws and rates on the date of enactment. Realization of the deferred income tax asset is dependent on gathering sufficient taxable income in future years.

Valuation allowances are established when necessary to reduce deferred tax assets to the amount expected to be realized. Income tax expense is the combination of the tax payable for the period and the change during the period in deferred tax assets and liabilities. We follow the accounting guidance on accounting for uncertainty in income taxes. The guidance prescribes a recognition threshold and measurement attribute criteria for the financial statement recognition and measurement of tax positions taken or expected to be taken in a tax return. For those benefits to be recognized, a tax position must be more likely than not to be sustained upon examination by taxing authorities based on the technical merits of the position.

Accumulated Other Comprehensive Income

Accumulated other comprehensive income is the result of unrealized gains and losses on marketable securities.

Net Loss per Common Share/Class A Common Unit Outstanding

Basic net loss per common share outstanding is computed by dividing net loss, after adjusting for dividends, if declared, by the weighted-average number of common shares outstanding during the period. Diluted net loss per common share outstanding is computed using the weighted-average number of common shares outstanding during the period and, if dilutive, the weighted average number of potential common shares. Potential common shares consist of unvested restricted stock and common shares issuable upon the exercise of stock options.

Adoption and Pending Adoption of Recent Accounting Pronouncements

The following table provides a brief description of recently issued accounting standards, those adopted in the current period and those not yet adopted:

Standard

Description

Effective Date

Effect on the Financial
Statements or Other
Significant Matters

In March 2020, the FASB issued ASU 2020-03, Codification Improvements to Financial Instruments.

The Guidance makes improvements to financial instrument guidance, including the current expected credit losses guidance.

January 1, 2020

We have adopted the new guidance as of January 1, 2020. The impact of adoption was not material to the consolidated financial statements.

In January 2020, the FASB issued ASU 2020-01, Investments — Equity Securities (Topic 321).

This standard clarifies the interaction between accounting standards related to equity securities (ASC 321), equity method investments (ASC 323), and certain derivatives (ASC 815)

January 1, 2021

We currently do not hold equity securities, have equity method investments or derivatives. We do not believe adoption will have a material impact on our consolidated financial position or results of operations.

In June 2016, the FASB issued ASU 2016-13, Financial Instruments—Credit Losses (Topic 326), Measurement of Credit Losses on Financial Instruments. In November 2018 and April and May of 2019, the FASB issued additional guidance related to Topic 326.

The standard amends the impairment model by requiring entities to use a forward-looking approach based on expected losses to estimate credit losses for most financial assets and certain other instruments that aren’t measured at fair value through net income.

January 1, 2020

We have adopted the new guidance as of January 1, 2020. The impact of adoption was not material to the consolidated financial statements.

In December 2019, the FASB issued ASU 2019-12, Simplifying the Accounting for Income Taxes.

The new guidance is intended to simplify aspects of the accounting for income taxes, including the elimination of certain exceptions to the guidance in ASC 740 related to the approach for intraperiod tax allocation, among other changes.

January 1, 2020

We have adopted the new guidance as of January 1, 2020. The impact of adoption was not material to the consolidated financial statements.

Business Combinations

12 Months Ended

Dec. 31, 2020

Business Combinations [Abstract]

Business Combinations

Kalyra Pharmaceuticals, Inc.

On December 21, 2017, we acquired $4.5 million of Kalyra Pharmaceuticals, Inc.’s Series B Preferred Stock representing a 25% equity interest in Kalyra Pharmaceuticals, Inc. for purposes of entering the analgesics therapeutic research space. The acquisition price was paid entirely in cash.

In accordance with the authoritative guidance, we concluded that Kalyra is a business consisting of inputs, employees, intellectual property and processes capable of producing outputs. Additionally, we have concluded that Kalyra is a variable interest entity, we are the primary beneficiary and have the power to direct the activities that most significantly affect Kalyra’s economic performance through common management and our board representation. Prior to the change of control, Zentalis and Kalyra transacted for the delivery of research and development services and support. The financial position and results of operations of Kalyra have been included in our consolidated financial statements from the date of the initial investment.

Pursuant with authoritative guidance, we have recorded the identifiable assets, liabilities and noncontrolling interests in the VIE at their fair value upon initial consolidation. The identified goodwill is comprised of the workforce and expected synergies from combining the entities. Total assets and liabilities of Kalyra as of December 31, 2020 and 2019 are as follows (in thousands):


	December 31,
	2020		2019
Cash and cash equivalents	$	417	$	712
Other current assets	82		21
In-process research and development	8,800		8,800
Goodwill	3,736		3,736
Other long-term assets	—		14
Accounts payable and accrued expenses	83		391
Deferred tax liability	2,463		2,463
Noncontrolling interests	6,705		6,821

The liabilities recognized as a result of consolidating Kalyra do not represent additional claims on our general assets. Pursuant to the authoritative guidance, the equity interest in Kalyra not owned by Zentalis is reported as a noncontrolling interest on our consolidated balance sheets.

The following is a reconciliation of equity (net assets) attributable to the noncontrolling interest (in thousands):


	December 31,
	2020		2019
Noncontrolling interest at beginning of period	$	6,821	$	7,536
Net loss attributable to noncontrolling interest	(116)		(715)
Noncontrolling interest at end of period	$	6,705	$	6,821

Fair Value Measurement

12 Months Ended

Dec. 31, 2020

Fair Value Disclosures [Abstract]

Fair Value Measurement

Available-for-sale marketable securities consisted of the following (in thousands):


	December 31, 2020
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Estimated Fair Value
Commercial paper	$	147,382	$	14	$	(8)	$	147,388
Corporate debt securities	23,576		1		(6)		23,571
US government agencies	81,455		32		(1)		81,486
US Treasury securities	31,105		4		—		31,109
	$	283,518	$	51	$	(15)	$	283,554

As of December 31, 2020, seventeen of our available-for-sale debt securities with a fair market value of $69.5 million were in a gross unrealized loss position of fifteen thousand dollars. When evaluating an investment for impairment, we review factors such as the severity of the impairment, changes in underlying credit ratings, forecasted recovery, our intent to sell or the likelihood that we would be required to sell the investment before its anticipated recovery in market value and the probability that the scheduled cash payments will continue to be made. Based on our review of these marketable securities, we believe none of the unrealized loss is as a result of a credit loss as of December 31, 2020, because we do not intend to sell these securities and it is not more-likely-than-not that we will be required to sell these securities before the recovery of their amortized cost basis.

Contractual maturities of available-for-sale debt securities are as follows (in thousands):


	December 31, 2020
	Estimated Fair Value
Due within one year	$	247,455
After one but within five years	36,099
	$	283,554

The following table summarizes, by major security type, our cash equivalents and available-for-sale marketable securities that are measured at fair value on a recurring basis and are categorized using the fair value hierarchy (in thousands):


	December 31, 2020						December 31, 2019
	Level 1		Level 2		Total estimated fair value		Level 1		Level 2		Total estimated fair value
Cash equivalents:
Money market funds	$	24,016	$	—	$	24,016	$	62,961	$	—	$	62,961


Corporate debt securities	—		4,999		4,999		—		—		—
Total cash equivalents:	24,016		4,999		29,015		62,961		—		62,961

Available-for-sale marketable securities:
Commercial paper	—		147,388		147,388		—		—		—
Corporate debt securities	—		23,571		23,571		—		—		—
US government agencies	—		81,486		81,486		—		—		—
US Treasury securities	31,109		—		31,109		—		—		—
Total available-for-sale marketable securities:	31,109		252,445		283,554		—		—		—

Total assets measured at fair value	$	55,125	$	257,444	$	312,569	$	62,961	$	—	$	62,961

There were no transfers between Level 1 and Level 2 of the fair value hierarchy during the year ended December 31, 2020. We had no instruments that were classified within Level 3 as of December 31, 2020 or 2019.

- 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

Prepaid Expenses and Other Assets

12 Months Ended

Dec. 31, 2020

Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]

Prepaid Expenses and Other Assets

Prepaid expenses and other assets consisted of the following (in thousands):


	December 31,
	2020		2019
Prepaid insurance	$	1,021	$	150
Prepaid software licenses and maintenance	563		238
Foreign R&D credit refund	692		—
Prepaid research and development expenses	5,963		2,985
Interest receivable	478		—
Other prepaid expenses	441		266
Total prepaid expenses and other current assets	9,158		3,639
Less long-term portion	2,976		2,134
Total prepaid expenses and other assets, current	$	6,182	$	1,505

Property and Equipment, net

12 Months Ended

Dec. 31, 2020

Property, Plant and Equipment [Abstract]

Property and Equipment, net

Property and equipment, net consisted of the following (in thousands):


	December 31,
	2020		2019
Computer and office equipment	$	529	$	243
Lab equipment	424		401
Leasehold improvements	49		24
Construction in process	347		—
Subtotal	1,349		668
Accumulated depreciation and amortization	(250)		(167)
Property and equipment, net	$	1,099	$	501

Depreciation and amortization expense was approximately $0.2 million and $0.1 million for the years ended December 31, 2020 and 2019, respectively.

Accrued Expenses

12 Months Ended

Dec. 31, 2020

Payables and Accruals [Abstract]

Accrued Expenses

Accrued expenses consist of the following (in thousands):


	December 31,
	2020		2019
Accrued research and development expenses	$	11,947	$	5,465
Accrued employee expenses	5,649		2,977
Accrued general and administrative expenses	996		1,356
Lease liability	902		781
Income taxes payable	410		—
Other	36		29
Total accrued expenses	$	19,940	$	10,608

Convertible Preferred Units

12 Months Ended

Dec. 31, 2020

Equity [Abstract]

Convertible Preferred Units

Series A Convertible Preferred Units

In September 2015, Zeno Pharmaceuticals, Inc. entered into a Series A Preferred Stock Purchase Agreement (the “Series A Preferred Agreement”). Under the terms of the Series A Preferred Agreement, Zeno Pharmaceuticals, Inc. issued 1,293,104 shares of Series A convertible preferred stock at $11.60 per share for gross proceeds of $15.0 million. The net proceeds of this financing were $14.9 million after issuance costs of $0.1 million. In February and March 2016, Zeno Pharmaceuticals, Inc. issued an aggregate of 286,205 additional shares of Series A convertible preferred stock at $11.60 per share for additional gross proceeds of $3.3 million. The issuance costs of this additional financing were approximately thirty-nine thousand dollars. All Series A convertible preferred stock issued and outstanding by Zeno Pharmaceuticals, Inc. was converted into Series A convertible preferred units of Zentalis Pharmaceuticals, LLC in conjunction with the corporate restructuring and merger (see note 9).

Series B Convertible Preferred Units

In December 2017, Zentalis Pharmaceuticals, LLC entered into a Series B Preferred Unit Purchase Agreement (the “Series B Preferred Agreement”). Under the terms of the Series B Preferred Agreement, Zentalis Pharmaceuticals, LLC issued 2,735,320 Series B preferred units at $12.43 per unit for gross proceeds of $34.0 million. The net proceeds of this financing were $32.1 million after issuance costs of $1.9 million. In January and August 2018, Zentalis Pharmaceuticals, LLC issued an aggregate of 788,419 additional shares of Series B preferred units at $12.43 per unit for additional gross proceeds of $9.8 million. The net proceeds of this additional financing were $9.5 million after issuance costs of $0.3 million.

Series C Preferred Unit Issuance

In September 2019, Zentalis Pharmaceuticals, LLC entered into a Series C Preferred Unit Purchase Agreement (the “Series C Preferred Agreement”). Under the terms of the Series C Preferred Agreement, Zentalis Pharmaceuticals, LLC issued 4,847,106 units of Series C convertible preferred units at $17.50 per unit for gross proceeds of $84.8 million. The net proceeds of this financing were $81.9 million after issuance costs of $2.9 million. In February 2020, Zentalis Pharmaceuticals, LLC issued 867,194 additional units of Series C preferred units under the Series C Preferred Agreement. The units were issued for $17.50 per unit for gross proceeds of $15.2 million. The net proceeds of this financing were $14.2 million after issuance costs of $1.0 million.

There were no authorized, issued, and outstanding shares of convertible preferred units at December 31, 2020. The authorized, issued, and outstanding shares of convertible preferred units at December 31, 2019 were as follows (in thousands, unless otherwise noted):


	December 31, 2019
Series	Units Authorized	Shares Issued and Outstanding	Liquidation Value		Carrying Value
Series A convertible preferred units	1,579,309	1,579,309	$	18,320	$	18,226
Series B convertible preferred units	3,523,739	3,523,739	43,800		41,604
Series C convertible preferred units	5,714,300	4,847,106	84,824		81,876
Total	10,817,348	9,950,154	$	146,944	$	141,706

During 2019, we reclassified the convertible preferred units to temporary equity because, in conjunction with the Series C convertible preferred units issuance, all units were now deemed to contain contingent liquidation features that are not solely within our control. During the year ended December 31, 2019 and prior to the conversion of convertible preferred units into common stock in conjunction with our IPO on April 2, 2020, we did not adjust the carrying values of the convertible preferred units to the deemed redemption values of such units since a liquidation event was not probable.

Dividends

Dividends are payable if and when declared by the Board of Directors. No dividends were declared prior to the conversion of convertible preferred units into common stock in conjunction with our IPO on April 2, 2020.

Conversion

Each Series A preferred unit, Series B preferred unit and Series C preferred unit was convertible at the option of the holder thereof, at any time after the issuance of such unit, into Class A common units at a conversion price equal to the original purchase price (subject to anti-dilution adjustments, discussed below) which was $11.60, $12.43 and $17.50 per unit, respectively. The convertible preferred units automatically converted at the then applicable conversion rate upon the closing of a firm commitment underwritten public offering of shares of a successor corporations’ common stock, at a public offering price per share of equal to or greater than the Series C original purchase price (as adjusted for any stock splits, stock dividends, combinations or other similar recapitalization) resulting in aggregate gross cash proceeds of at least $75.0 million (a “Qualified IPO”). Additionally, the convertible preferred unit would have automatically converted into common stock, at the then applicable conversion rate, upon written consent of a majority of the then outstanding Series A, Series B and Series C convertible preferred units (voting as a separate class on an as converted to Common Unit basis). In conjunction with our IPO on April 2, 2020, which constituted a Qualified IPO, all convertible preferred units were converted into common stock.

Anti-dilution protection

The holders of the convertible preferred units had proportional anti-dilution protection for unit splits, unit dividends and similar recapitalizations. Subject to certain exclusions, anti-dilution price protection for additional sales of securities by us for consideration per unit less than the applicable conversion price per unit of any series of convertible preferred stock, was on a broad-based weighted average basis.

Protective rights

The holders of the convertible preferred units had certain protective rights, including, without limitation, regarding the authorization, alteration, redemption, or sale of Class B common units; commencement of a liquidation or deemed liquidation

event; entrance into a joint venture or partnership; any incurrence of indebtedness; certain transactions that exceed a certain dollar threshold; changes to our governing documents; or the declaration of any dividends. Such actions were required to be approved by a majority of the then outstanding Series A, Series B and Series C convertible preferred unit holders (voting as a single class and on an as-converted basis), as specified in the amended and restated LLC agreement. An increase or decrease in the authorized number of Directors constituting the Board or the creation of a membership interest or equity security senior to or pari passu with Series C convertible preferred units was required to be approved by a majority of the then outstanding Series C convertible preferred Units (voting as a separate class on an as converted basis).

Redemption

The Series A, Series B and Series C convertible preferred units were not redeemable except in the event of certain effected deemed liquidation events. As of immediately prior to the our IPO on April 2, 2020 and December 31, 2019 we had classified convertible preferred units as temporary equity in accordance with authoritative guidance for the classification and measurement of potentially redeemable securities whose redemption is based upon certain change in control events outside of our control, including liquidation, sale or transfer of control of the Company. We did not adjust the carrying value of the convertible preferred units to the deemed redemption values of such units since a liquidation event was not probable.

Liquidation preference

In the event of the dissolution, liquidation, merger or winding up of the Company, the holders of Series C convertible preferred units were entitled to receive, on a pro rata basis in respect of each such Series C convertible preferred unit, a preference amount of $17.50 per Series C convertible unit (as adjusted for any unit splits, dividends, combinations, recapitalizations or the like).

Subsequent to the payment of the Series C convertible preferred unit preferences, Series A and Series B convertible preferred units were entitled to receive, on a pro rata basis in respect of each convertible preferred unit in proportion to the relative preference amount of each preferred unit, a preference amount of $11.60 and $12.43 per unit of Series A and Series B convertible preferred units (as adjusted for any units splits, dividend, combinations, recapitalizations of the like), respectively.

Subsequent to the payment of the Series C, Series A and Series B convertible preferred unit preferences, Series A, Series B and Series C convertible preferred units are entitled to receive, on an as converted to common unit pro rata basis, an amount equal to distributions made to Class A common units prior to all unit classes sharing in distributions on a pro rata basis. Thereafter, Series A, Series B and Series C convertible preferred units and Series A and Series B common units were entitled to receive the remaining assets of the Company available for distribution to its unit holders pro rata based on the number of common units held by each holder, treating for these purposes as if all units had been converted to common.

Voting Rights

The holders of all units other than Class B common units that were unvested shall were to vote together as a single class. Each holder of Series A, Series B and Series C convertible preferred units were entitled to the number of votes calculated on an as converted to Class A common unit basis.

Equity and Share-based Compensation

12 Months Ended

Dec. 31, 2020

Equity [Abstract]

Equity and Share-based Compensation

In November 2017, Zentalis Pharmaceuticals, LLC was formed in the state of Delaware. In conjunction with a corporate restructuring, Zeno Pharmaceuticals, Inc., a Delaware corporation formed in 2014, was acquired by the Company pursuant to a merger agreement and became a wholly owned subsidiary of the Company. Per the terms of the merger agreement, each share of Zeno Pharmaceuticals, Inc. common stock issued and outstanding immediately prior to the effective time of the merger was converted into the right to receive one Class A common unit and each share of Zeno Pharmaceuticals, Inc. Series A preferred stock issued and outstanding immediately prior to the effective date of the merger converted into the right to receive one Series A preferred unit. As of the effective time of the merger agreement, all outstanding options to purchase shares of Zeno Pharmaceuticals, Inc. common stock were cancelled and replaced with profit interest awards in the LLC.

In connection with the December 2017 corporate restructuring, we amended and restated the LLC agreement, and as amended, the capital units of the Company consisted of 1,638,000 authorized Series A preferred units, 3,621,000 authorized Series B preferred units, 15,000,000 authorized Class A common units and 872,620 authorized Class B common units.

Class A Common Units

In conjunction with the corporate restructuring in December 2017, 5,187,554 shares of common stock issued and outstanding and 406,831 shares of common stock subject to future vesting provisions of Zeno Pharmaceuticals, Inc. were converted into an equal number of Class A common units of Zentalis Pharmaceuticals, LLC. During the years ended December 31, 2020 and 2019, zero and 7,093 Class A common units were issued. As of December 31, 2020 and 2019, zero and 9,572 Class A common units were subject to future vesting conditions, respectively. In September 2019, the number of authorized Class A common units was increased to 20,000,000.

Class B Common Units

In conjunction with the corporate restructuring in December 2017, 703,000 options exercisable into Zeno Pharmaceuticals, Inc. common stock were converted into an equal number of Class B common units of Zentalis Pharmaceuticals, LLC. In September 2019, the number of authorized Class B common units was increased to 3,458,522.

IPO

On April 2, 2020 and immediately prior to the effectiveness of the Company’s IPO, Zentalis Pharmaceuticals, LLC converted from a Delaware limited liability company into a Delaware corporation pursuant to a statutory conversion, and changed its name to Zentalis Pharmaceuticals, Inc. In order to consummate the corporate conversion, a certificate of conversion was filed with the Secretary of State of the State of Delaware. All of the outstanding units of Zentalis Pharmaceuticals, LLC converted into shares of common stock of Zentalis Pharmaceuticals, Inc. based upon the value of Zentalis Pharmaceuticals, Inc. at the time of the IPO with a value implied by the price of the shares of common stock sold in the IPO. No cash or fractional shares of common stock were issued in connection with the corporate conversion. Based on the IPO price of $18.00 per share of common stock, all of the outstanding units converted into an aggregate of 25,288,854 shares of common stock (including 1,160,277 shares of restricted common stock).

In connection with the completion of the IPO, the board and stockholders approved the certificate of incorporation to provide for 250,000,000 authorized shares of common stock with a par value of $0.001 per share and 10,000,000 authorized shares of preferred stock with a par value of $0.001 per share.

On April 7, 2020, the Company completed the IPO in which the Company issued and sold 10,557,000 shares of common stock (including 1,377,000 shares of common stock in connection with the full exercise of the underwriters’ option to purchase additional shares) at a price of $18.00 per share. The Company’s aggregate gross proceeds from the sale of shares in the IPO, including the sale of shares pursuant to the full exercise of the underwriters’ option to purchase additional shares, was $190.0 million before fees and expenses of $17.6 million.

On August 3, 2020, the Company completed a follow-on offering in which the Company issued and sold 4,743,750 shares of common stock (including 618,750 shares of common stock in connection with the full exercise of the underwriters' option to purchase additional shares) at a public offering price of $35.00 per share. The Company's aggregate gross proceeds from the sale of shares in the follow-on offering, including the sale of shares pursuant to the exercise of the underwriters' option to purchase additional shares, was $166.0 million before fees and expenses of $10.8 million.

Share-based Compensation

In the Company’s 2017 Profit Interest Plan ("the Plan") as approved and adopted by the Board of Directors on December 21, 2017, the Company was authorized to issue up to 3,458,522 shares of Class B common units ("profit interest award units"), subject to restrictions as described in the Plan.

In April 2020, the Plan was terminated and the Company’s board of directors adopted, and the Company’s stockholders approved the 2020 Incentive Award Plan ("the 2020 Plan"), which became effective upon the corporate conversion.

The number of common shares available for issuance under the 2020 Plan is the sum of (1) 5,600,000 shares of common stock; plus (2) any shares forfeited from the unvested restricted shares of our common stock issued upon conversion of unvested Class B common units (up to 1,250,000 shares); plus (3) an annual increase on the first day of each fiscal year beginning with the fiscal year ending December 31, 2021 and continuing to, and including, the fiscal year ending December 31, 2030, equal to the lesser of (a) 5% of the shares of common stock outstanding on the final day of the immediately preceding calendar year and (b) such smaller number of shares as determined by our board of directors.

In connection with the corporate conversion, each outstanding profits interest award unit was converted into a number of shares of common stock and restricted common stock based upon the IPO price. The restricted common stock issued in respect

of profits interest award units continues to be subject to vesting in accordance with the vesting schedule that was applicable to such profits interest award units.

Total share-based compensation expense related to share based awards was comprised of the following (in thousands):


	Year ended December 31,
	2020		2019
Research and development expense	$	7,296	$	339
General and administrative expense	15,850		278
Total share-based compensation expense	$	23,146	$	617

Share-based compensation expense by type of share-based award (in thousands):


	Year ended December 31,
	2020		2019
Profits interest award units	$	329	$	617
Stock options	6,925		—
RSAs and RSUs	15,892		—
	$	23,146	$	617

Total unrecognized estimated compensation cost by type of award and the weighted average requisite service period over which such expense is expected to be recognized (in thousands, unless otherwise noted):


	December 31, 2020
	Unrecognized Expense		Remaining Weighted-Average Recognition Period (Years)
Stock options	$	45,501	3.5
RSAs	2,197		2.5
RSUs	13,078		1.0

Profits Interest Award Units: The following table provides a summary of the profits interest units award activity under the Plan. The amounts include profits interest units granted to both employees and non-employees:


	Number of Units	Weighted Average Fair Value
Outstanding at December 31, 2018	1,612,311	$	1.56
Granted	1,095,545	$	2.73
Forfeited	(37,188)	$	1.62
Outstanding at December 31, 2019	2,670,668	$	2.04
Granted	70,000	$	3.06
Cancelled upon conversion	(2,740,668)	$	2.07
Outstanding at December 31, 2020	—	$	—

The fair value of the profits interest award units was estimated using an option pricing model with the following assumptions:


	Year ended December 31,
	2020	2019
Members’ equity value (in thousands)	$271,207	$197,041 - $271,207
Threshold amounts (in thousands)	$309,824	$143,800 - $309,824
Risk-free rate	1.5%	1.5%
Volatility	75.0%	75.0%
Time to liquidity (in years)	1.1	1.1 - 1.8
Lack of marketability discount	26.5%	18.8% - 26.4%
Grant date fair value	$3.06	$1.88 - $3.06

The Black-Scholes-Merton option pricing model (“Black-Scholes model) was used to estimate the fair value of each profit interest award units on the date of grant. The members’ equity value was based on a recent enterprise valuation analysis performed. The threshold amounts were determined by the Board of Directors at the time of grant. The expected life of the profits interest award units granted during the period presented was determined based on an expected liquidation event under the plan. We applied the risk-free interest rate based on the U.S. Treasury yield in effect at the time of the grant consistent with the life of the award. The expected volatility was based on a peer group in the industry in which the Company does business consistent with the expected time to liquidity. The dividend yield was set at zero as the underlying security does not and is not expected to pay a dividend. The Finnerty model and the Asian Protective Put Model methods were used to estimate the discount for lack of marketability inherent to the awards.

Stock Options: The following table provides a summary of the stock option activity under the 2020 Plan. The amounts include incentive units granted to both employees and non-employees (in thousands, unless otherwise noted):


	Number of Shares	Weighted Average Exercise Price		Weighted Average Remaining Contractual Term (Years)	Aggregate Intrinsic Value
Outstanding at December 31, 2019	—
Granted	3,137,746
Cancelled	(16,525)
Outstanding at December 31, 2020	3,121,221	$	25.45	9.4	$82,691
Vested and expected to vest at December 31, 2020	3,121,221	$	25.45	9.4	$82,691
Exercisable at December 31, 2020	42,691	$	22.07	9.3	$1,275

The weighted average grant date fair value of stock options granted during the year ended December 31, 2020 was $16.79.

The exercise price of stock options granted is equal to the closing price of the common stock on the date of grant. The fair value of each option award is estimated on the date of grant using the Black-Scholes model. Due to the Company’s limited operating history and a lack of company specific historical and implied volatility data, the Company estimates expected volatility based on the historical volatility of a group of similar companies that are publicly traded. The historical volatility data was computed using the daily closing prices for the selected companies’ shares during the equivalent period of the calculated expected term of the stock-based awards. The Company uses the “simplified method” for estimating the expected term of employee options, whereby the expected term equals the arithmetic average of the vesting term and the original contractual term of the option (generally 10 years). The risk-free interest rate is based on the U.S. Treasury yield for a period consistent with the expected term of the option in effect at the time of the grant. The Company has not issued any dividends and does not expect to issue dividends over the life of the options. As a result, the Company has estimated the dividend yield to be zero. The fair value of the stock options granted during the year ended December 31, 2020 was determined with the following assumptions:


			Year ended December 31,
			2020
Expected volatility			76.4% - 78.7%
Average expected term (in years)			1.0 - 6.0
Risk-free interest rate			0.1% - 0.5%
Expected dividend yield			—%

Restricted Stock Awards: RSAs are shares of our common stock subject to forfeiture restrictions that lapse based on the awardee's continued employment or service. The shares covered by a RSA cannot be sold, pledged or otherwise disposed of until the awards vest, and any unvested shares will be forfeited following the awardee's termination of service.

The following table provides a summary of the RSA activity. The amounts include incentive units granted to both employees and non-employees:


	Number of Shares	Weighted Average Grant Date Fair Value
Outstanding at December 31, 2019	—	$	—
Conversion of unvested profit interest award units into RSAs	1,160,277	$	2.91
Vested	(409,259)	$	2.70
Forfeited	(8,607)	$	2.70
Outstanding at December 31, 2020	742,411	$	3.03

The fair value of RSAs issued upon conversion of the unvested profit interest award units was based on a Black-Scholes pricing model. The estimated fair value of the RSAs for any future grants will be based on the closing market value of our common stock on the date of grant.

Restricted Stock Units: A RSU is a promise by us to issue a share of our common stock upon vesting of the unit.

The following table provides a summary of the restricted stock unit ("RSU") activity under the 2020 Plan. The amounts include incentive units granted to both employees and non-employees:


	Number of Shares	Weighted Average Grant Date Fair Value
Outstanding at December 31, 2019	—	$	—
Granted	1,145,875	$	23.75
Vested	(426,625)	$	23.75
Forfeited	(44,493)	$	23.75
Outstanding at December 31, 2020	674,757	$	23.75

The estimated fair value of the RSUs was based on the closing market value of our common stock on the date of grant.

Employee Stock Purchase Plan

In April 2020, the Company’s board of directors adopted, and the Company’s stockholders approved the 2020 Employee Stock Purchase Plan (the “2020 ESPP”), which became effective upon the corporate conversion. The number of common shares initially available for issuance under the 2020 ESPP was the sum of (1) 450,000 shares of common stock; plus (2) an annual increase on the first day of each fiscal year beginning with the fiscal year ending December 31, 2021 and continuing to, and including, the fiscal year ending December 31, 2030, equal to the least of (a) 1% of the shares of common stock outstanding on the final day of the immediately preceding calendar year, (b) 1,500,000 shares and (c) such smaller number of shares as determined by our board of directors. The 2020 ESPP was amended and restated effective March 15, 2021 to provide for a share reserve of 2,000,000 shares and the elimination of the evergreen provision, subject to stockholder approval.

Commitment and Contingencies

12 Months Ended

Dec. 31, 2020

Commitments and Contingencies Disclosure [Abstract]

Commitments and Contingencies

Legal Contingencies

From time to time, we may be involved in various disputes, including lawsuits and claims arising in the ordinary course of business, including actions with respect to intellectual property, employment and contractual matters. Any of these claims could subject us to costly legal expenses. The Company records a liability in its consolidated financial statements for these matters when a loss is known or considered probable and the amount can be reasonably estimated. The Company reviews these estimates each accounting period as additional information is known and adjusts the loss provision when appropriate. If a matter is both probable to result in a liability and the amounts of loss can be reasonably estimated, the Company estimates and discloses the possible loss or range of loss to the extent necessary to make the consolidated financial statements not misleading. If the loss is not probable or cannot be reasonably estimated, a liability is not recorded in our consolidated financial statements. While we do generally believe that we have adequate insurance to cover many different types of liabilities, our insurance carriers may deny coverage, or our policy limits may be inadequate to fully satisfy any damage awards or settlements. If this were to happen, the payment of any such awards could have a material adverse effect on our consolidated results of operations and financial position. Additionally, any such claims, whether or not successful, could damage our reputation and business. We are currently not a party to any legal proceedings.

Operating Leases

We entered into a non-cancellable operating lease agreement in January 2016 to lease 11,121 square feet of laboratory and office space in San Diego. In December 2018, we entered into an amendment to the lease to extend the term of the agreement through June 2022. The lease is subject to further extension or earlier termination and subject to approximately 3.0% annual increases throughout the term of the lease. We also pay a pro rata share of operating costs, including utilities, maintenance, insurance costs and real property taxes. As part of the amendment, we received incentives in the form of a base rate abatement period.

In April 2019, we entered into a lease for approximately 4,800 square feet of office space in New York, New York. The lease commenced in May 2019 and continues through June 30, 2023. The lease is subject to approximately 3.0% annual increases throughout the term of the lease. We received lease incentives under the agreement, including tenant allowances and a free rent period. We also pay for various operating costs, including utilities and real property taxes. The agreement does not contain a renewal option but does contain an early termination provision.

In August 2019, we entered into a sublease for approximately 2,333 square feet of office space adjacent to the existing laboratory and office space in San Diego, California. The lease commenced in October 2019 and continues through February 2022. The lease is subject to approximately 3.0% annual increases throughout the term of the lease. We also pay for various operating costs, including utilities and real property taxes. The agreement does not contain a renewal option or an early termination provision.

In September 2020, we entered into a lease for approximately 117,929 square feet of laboratory and office space in San Diego. The lease is expected to commence in November 2021 and to continue through June 2032. The lease also included

access to a temporary space of 13,251 square feet of laboratory and office space in San Diego. This lease component commenced in November 2020 and is expected to continue through December 2021. The lease is subject to approximately 3.0% annual increases throughout the lease term. We also pay for various operating costs, including utilities and real property. The agreement includes two options to extend the lease for a period of five years each. When we determined our lease term for our operating lease right-of-use assets and lease liabilities for these leases, we did not include the extension options for this lease.

Rent expense recorded by the Company under the leases was approximately $1.1 million and $0.8 million for the years ended December 31, 2020 and 2019, respectively. We paid approximately $1.0 million and $0.7 million of lease payments, respectively, during the years ended December 31, 2020 and 2019.

The following table presents the weighted average remaining lease term and weighted average discount rates related to our operating leases as of December 31, 2020:


Weighted average remaining lease term (in years)			1.8
Weighted average discount rate			10.7%

Approximate annual future minimum operating lease payments as of December 31, 2020 are as follows (in thousands):


Year	Amount
2021	$	1,052
2022	1,005
2023	187



Total minimum lease payments:	2,244
Less: imputed interest	245
Total operating lease liabilities	1,999
Less: current portion	902
Lease liability, net of current portion	$	1,097

As of December 31, 2020, we have had one additional significant operating lease that had not yet commenced with total minimum lease payments of approximately $85.6 million.

Income Taxes

12 Months Ended

Dec. 31, 2020

Income Tax Disclosure [Abstract]

Income Taxes

Pretax losses were generated by both domestic and foreign operations as follows (in thousands):


	Year ended December 31,
	2020		2019
U.S. net loss before income taxes	$	(112,827)	$	(46,363)
Foreign net loss before income taxes	(5,277)		—
Net loss before income taxes	$	(118,104)	$	(46,363)

The following table presents the current and deferred income tax provision (benefit) for federal and state income taxes (in thousands):


	Year ended December 31,
	2020		2019
Current tax provision:
Federal	$	—	$	—
State	16		15
Foreign	410		—
Total current tax provision	426		15
Deferred tax provision:
Federal	—		—
State	—		—
Foreign	18		—
Total deferred tax provision	18		—
Total provision for income taxes:	$	444	$	15

The following table is a reconciliation of the expected tax computed at the U.S. statutory federal income tax rate to the total provision for income taxes (in thousands):


	Year ended December 31,
	2020				2019
Expected tax at 21%	$	(24,802)	21.0	%	$	(9,730)	21.0	%
State income tax, net of federal tax	273		(0.3)	%	(3,167)		6.8	%
Limited liability company loss	—		—	%	4		—	%
Non-deductible expenses	—		—	%	164		(0.3)	%
Research credits	(4,025)		3.4	%	(1,424)		3.1	%
Share-based compensation	(1,718)		1.5	%	—		—	%
Other	146		(0.1)	%	(2)		—	%
Section 162(m) limitations	2,956		(2.5)	%	—		—	%
Change in valuation allowance	27,614		(23.4)	%	14,170		(30.6)	%
Provision for income taxes	$	444	(0.4)	%	$	15	0.0	%

Deferred income taxes as of the following period reflect the net tax effects of temporary differences between the carrying amounts of assets and liabilities for financial reporting purposes and the amounts used for income tax purposes.

Significant components of our net deferred tax asset or liability are as follows (in thousands):


	December 31,
	2020		2019
Deferred tax assets
Net operating loss	$	45,730	$	25,053
Compensation	892		148
Share-based compensation	1,691		—
ASC 842 lease liability	425		693
Accrued liabilities	632		1
Research credits	7,528		3,503
Total gross deferred tax assets	56,898		29,398
Valuation allowance	(56,261)		(28,647)
Net deferred tax assets	637		751
Deferred tax liabilities
Depreciable assets	(145)		(97)
ASC 842 right of use asset	(502)		(654)
In-process research and development	(2,463)		(2,463)
Other	(7)		—
Deferred tax liabilities	(3,117)		(3,214)
Net deferred tax liabilities	$	(2,480)	$	(2,463)

Realization of a portion of our deferred tax assets is dependent upon our generating sufficient taxable income in future years to obtain benefit from the reversal of temporary differences. Management considered all available evidence under existing tax law and anticipated expiration of tax statutes and determined that a valuation allowance of $56.3 million and $28.6 million was required as of December 31, 2020 and 2019, for those deferred tax assets that are not expected to provide future tax benefits.

The acquisition of Kalyra resulted in an allocation of the purchase price to In-process Research and Development (IPR&D). Intangible assets acquired in a business combination that are used for IPR&D activities are considered indefinite lived until the completion or abandonment of the associated research and development efforts. As a result of being treated as an indefinite lived asset, the deferred tax liability is not considered to be a future source of taxable income for purposes of determining the Company’s realizability of definite lived deferred tax assets and the amount of the valuation allowance to record. We have adopted an accounting policy to not consider indefinite lived deferred tax liabilities as a future source of taxable income with respect to determining the realizability of indefinite lived deferred tax assets and the amount of valuation allowance recorded against the deferred asset related to the federal net operating losses generated beginning January 1, 2018 and the California R&D tax credits, which do not expire.

At December 31, 2020, we have federal and state net operating loss ("NOL") carryforwards of approximately $183.0 million and $85.1 million, respectively. The federal NOL carryforwards generated prior to January 1, 2018 begin to expire in 2033. The federal NOL carryforwards generated after 2017 of $162.0 million can be carried forward indefinitely and can be available to offset future taxable income each year. The state NOL carryforwards begin to expire in 2033. At December 31, 2020, the Company has foreign NOL carryforwards related to Chinese operations of approximately $5.8 million that begin to expire in 2025.

At December 31, 2020, we have federal and state research tax credit carryforwards, net of reserves, of approximately $5.2 million and $2.3 million, respectively. The federal credit carryforwards begin to expire in 2033, and the state credit carryforwards do not expire and can be carried forward indefinitely until utilized.

We have not completed a study to determine whether an ownership change per the provisions of Section 382 of the Internal Revenue Code of 1986, as amended, as well as similar state provisions, has occurred. Utilization of our net operating loss and income tax credit carryforwards may be subject to a substantial annual limitation due to ownership changes that may have occurred or that could occur in the future. These ownership changes may limit the amount of the net operating loss and

income tax credit carryover that can be utilized annually to offset future taxable income. In general, an “ownership change” as defined by Section 382 of the Code results from a transaction or series of transactions over a three-year period resulting in an ownership change of more than 50 percentage points of the outstanding stock of a company by certain stockholders.

Uncertain Tax Positions

In accordance with authoritative guidance, the impact of an uncertain income tax position on the income tax return must be recognized at the largest amount that is more-likely-than-not to be sustained upon audit by the relevant taxing authority. An uncertain income tax position will not be recognized if it has less than a 50% likelihood of being sustained.

The following table reconciles the beginning and ending amount of unrecognized tax benefits for the years ended December 31, 2020 and 2019 (in thousands):


	December 31,
	2020		2019
Gross unrecognized tax benefits at the beginning of the year	$	1,124	$	741
Increase related to current year tax positions	661		383
Increase related to prior year tax positions	197		—
Decrease related to prior year tax positions	(50)		—
Gross unrecognized tax benefits at end of the year	$	1,932	$	1,124

Included in the balance of unrecognized tax benefits at December 31, 2020 is $1.7 million that, if recognized, would not impact our income tax benefit or effective tax rate as long as our deferred tax asset remains subject to a valuation allowance. We do not expect any significant increases or decreases to our unrecognized tax benefits within the next 12 months.

We recognize interest and penalties related to unrecognized tax positions within the income tax expense line in the accompanying consolidated statements of operations. There were no accrued interest and penalties associated with uncertain tax positions as of December 31, 2020 or 2019.

The Company files federal and state income tax returns in the United States as well as income tax returns in Australia and China. Due to the Company's unutilized NOL carryforwards and credits in the United States, all years remain subject to income tax examination by authorities. The Company's Australian and Chinese tax returns remain subject to income tax examination by the taxing authorities for years beginning 2020. The Company is not currently under examination by federal, state or foreign jurisdictions.

In response to the COVID-19 pandemic, the Coronavirus Act, Relief and Economic Security Act (CARES Act) was signed into law in the U.S. in March 2020. The CARES Act adjusted a number of provisions of the tax code, including the eligibility of certain deductions and the treatment of net operating losses and tax credits. The enactment of the CARES Act did not result in any material adjustments to the Company's income tax provision for the year ended December 31, 2020, or to its deferred tax assets as of December 31, 2020.

California NOL carryforwards for any taxable year beginning on or after January 1, 2020, and before January 1, 2023 for any Corporation with a net business or modified adjusted gross income of more than $1.0 million for the taxable year. The bill also limits business credit utilization to offset a maximum of $5.0 million of California tax, including the California Research Credit. The Company does not expect any material impacts related to this tax law change.

- 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 + Details

Net Loss Per Common Share/Class A Common Unit

12 Months Ended

Dec. 31, 2020

Earnings Per Share [Abstract]

Net Loss Per Common Share/Class A Common Unit

Basic and diluted net loss per common share/Class A common unit were calculated as follows (in thousands except per share amounts):


	Year ended December 31,
	2020		2019
Numerator:
Net loss attributable to Zentalis	$	(117,841)	$	(45,663)
Denominator:
Weighted average number of common shares/Class A common units outstanding, basic and diluted	28,113		5,597
Net loss per common share	$	(4.19)	$	—
Net loss per Class A common unit	$	—	$	(8.16)

Our potential and dilutive securities, which include outstanding stock options, unvested RSAs, unvested RSUs and preferred units, have been excluded from the computation of diluted net loss per common share/Class A common unit as the effect would be anti-dilutive. We considered the impact of presenting a separate earnings per unit calculation for Class B common units. However, as earnings and losses are only allocable to Class B common units after the applicable threshold had been met, and such thresholds had not been met for earnings per unit purposes, no losses were allocated to Class B common units.

The following common stock/Class A common unit equivalents have been excluded from the calculations of diluted net loss per common share/Class A common unit because their inclusion would be antidilutive (in thousands).


	Year ended December 31,
	2020	2019
Preferred units, as if converted to Class A common units	—	9,950
Incentive units—Class B common units	—	2,671
Outstanding stock options	3,121	—
Unvested RSAs	742	—
Unvested RSUs	675	—
	4,538	12,621

Employee Savings Plan	12 Months Ended
Employee Savings Plan	Dec. 31, 2020
Retirement Benefits [Abstract]
Employee Savings Plan	Employee Savings PlanWe have an employee savings plan pursuant to Section 401(k) of the Internal Revenue Code. All employees are eligible to participate provided that they meet the requirements of the plan. The Company did not begin making matching contributions under the plan until subsequent to December 31, 2020.

- Definition

The entire disclosure for retirement benefits.

+ References

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+ Details

Related Party Disclosures	12 Months Ended
Related Party Disclosures	Dec. 31, 2020
Related Party Transactions [Abstract]
Related Party Disclosures	Related Party Disclosures Kalyra Pharmaceuticals, Inc. On December 21, 2017, we acquired 17,307,692 shares of Series B preferred stock of Kalyra Pharmaceuticals, Inc. for a per share price of twenty-six cents ($0.26) or approximately $4.5 million. The management team and stockholders of Kalyra are also stockholders of the Company. Prior to the investment, we entered into a license agreement and a master services agreement with Kalyra. The license agreement was signed and commenced on December 31, 2014 for the exclusive rights to develop and commercialize products derived from Kalyra’s technology in the initial area of oncology. The license agreement and all rights were subsequently sold from Kalyra to Recurium IP Holdings, LLC (“Recurium IP”), an entity with common ownership to Kalyra prior to the Zentalis investment. Under the agreement, we have agreed to make payments to Recurium IP based on specific milestones. In addition, the Company shall pay mid- to high-single digit percentage royalties on net product sales to Recurium IP and sublicense fees on any consideration paid to us by a sublicensor. All payments are based on Recurium Equity, LLC’s, an affiliated company of Recurium IP, equity ownership stake in us as of December 2020. The license agreement will terminate upon the later of the last expiration of the patent rights or 15 years from the date of commencement. The Master Services Agreement (“MSA”) was entered into in January 2015 and states that Kalyra may provide research and development services to us and that we shall reimburse such expenses on a time and materials basis based on the initial statements of work. For the years ended December 31, 2020 and 2019, we incurred approximately zero dollars and five thousand dollars of expense with Kalyra that was eliminated in consolidation for research and development services provided, respectively. As of December 31, 2020 and 2019, zero and seventeen thousand dollars was due to Kalyra and eliminated in consolidation. We entered into an Intercompany Services Agreement (“ISA”) with Kalyra in January 2018 which states that we may provide research and development services to Kalyra and that Kalyra shall reimburse such expenses on a time and materials basis. For the years ended December 31, 2020 and 2019, we provided $0.2 million and $0.7 million of research and development services to Kalyra that was eliminated in consolidation, respectively. As of December 31, 2020 and 2019, twenty-two thousand dollars and $0.2 million was due from Kalyra and eliminated in consolidation, respectively. On June 1, 2020, we entered into an equipment purchase and sale agreement with Kalyra to purchase $0.4 million of equipment and related intangible assets to be used in our operations. As of December 31, 2020, there was no balance due to Kalyra for this transaction. Tempus Kimberly Blackwell, M.D., is a member of the Company's board of directors and is also the Chief Medical Officer of Tempus Labs, Inc. ("Tempus"). The Company entered into a Master Services Agreement with Tempus in December 2020 to provide data licensing and research services. There were no fees incurred for services performed by Tempus for the years ended December 31, 2020 and 2019.

Selected Quarterly Financial Data (Unaudited)

12 Months Ended

Dec. 31, 2020

Quarterly Financial Information Disclosure [Abstract]

Selected Quarterly Financial Data (Unaudited)

Selected quarterly financial data is as follows:


	Three months ended
	3/31/2020		6/30/2020		9/30/2020				12/31/2020
Operating Expenses
Research and development	$	13,258	$	17,452	$	24,670			$	29,521
General and administrative	3,141		$	9,924	$	10,097			10,724
Total operating expenses	16,399		27,376		34,767				40,245
Operating loss	(16,399)		(27,376)		(34,767)				(40,245)
Other Income (Expense)
Investment and other income (expense), net	164		$	84	$	120			315
Net loss before income taxes	(16,235)		(27,292)		(34,647)				(39,930)
Income tax expense	—		—		$	18			426
Net loss	(16,235)		(27,292)		(34,665)		$	—	(40,356)
Net loss attributable to noncontrolling interests	(109)		(435)		(110)				(53)
Net loss attributable to Zentalis	$	(16,126)	$	(26,857)	$	(34,555)			$	(40,303)
Net loss per common share outstanding, basic and diluted			$	(0.78)	$	(0.91)			$	(1.01)
Net loss per Class A common unit outstanding, basic and diluted	$	(2.88)
Common shares/units used in computing net loss per share/Class A common unit, basic and diluted	5,601		34,353		37,959				39,936


	Three months ended
	3/31/2019		6/30/2019		9/30/2019				12/31/2019
Operating Expenses
Research and development	$	7,089	$	8,689	$	10,739			$	11,869
General and administrative	1,633		1,946		1,844				3,036
Total operating expenses	8,722		10,635		12,583				14,905
Operating loss	(8,722)		(10,635)		(12,583)				(14,905)
Other Income (Expense)
Investment and other income (expense), net	62		49		12				359
Net loss before income taxes	(8,660)		(10,586)		(12,571)				(14,546)
Income tax expense	3		11		1				—
Net loss	(8,663)		(10,597)		(12,572)		$	—	(14,546)
Net loss attributable to noncontrolling interests	(320)		(127)		(228)				(40)
Net loss attributable to Zentalis	$	(8,343)	$	(10,470)	$	(12,344)			$	(14,506)
Net loss per Class A common unit outstanding, basic and diluted	$	(1.49)	$	(1.87)	$	(2.20)			$	(2.59)
Common units used in computing net loss per Class A common unit, basic and diluted	5,594		5,594		5,599				5,601

Subsequent Events

12 Months Ended

Dec. 31, 2020

Subsequent Events [Abstract]

Subsequent Events

New York Office Lease

In March 2021, we entered into a lease for approximately 31,362 square feet of office space in New York, New York. The targeted lease commencement date is November 2021 and will continue for 120 months thereafter. We also pay for various operating costs, including utilities and real property taxes. The agreement contains extension rights allowing us to extend the term of the lease for five years at the then market rate. The agreement contains an early termination provision exercisable after the eighth anniversary of the commencement date.

The expected future minimum lease obligation are as follows (in thousands):


Year-ending December 31,	Payment Amount
2021	$	—
2022	1,458
2023	1,458
2024	1,459
2025	1,782
Thereafter	11,970
Total minimum lease payments:	$	18,127

Summary of Significant Accounting Policies (Policies)

12 Months Ended

Dec. 31, 2020

Accounting Policies [Abstract]

Basis of Presentation

Consolidation

Noncontrolling Interests

Use of Estimates

Cash and Cash Equivalents and Restricted Cash

Cash and Cash Equivalents

Restricted CashUnder the terms of our office leases, we are required to maintain a letter of credit as a security deposit during the term of such leases. At December 31, 2020 and 2019, restricted cash of $1.3 million and $0.2 million, respectively, was pledged as collateral for the letters of credit.

Marketable Securities

Marketable SecuritiesMarketable securities are investments with original maturities of more than ninety days from the date of purchase that we have the ability to liquidate to find current operations. Accordingly, those investments with contractual maturities greater than one year from the date of purchase are classified as short-term investments on the accompanying consolidated balance sheets. Marketable securities are considered available-for-sale and are carried at fair value with unrealized gains and losses recorded in other comprehensive income (loss) and included as a separate component of stockholders' equity. The cost of marketable securities is adjusted for amortization of premiums or accretion of discounts to maturity, and such amortization or accretion is included in investment and other income, net through an allowance account. We use the specific identification method for calculating realized gains and losses on marketable securities sold. Realized gains and losses on marketable securities, if any, are included in investment and other income, net in the consolidated statements of operations.

Fair Value of Financial Instruments

Concentrations of Credit Risk and Sources of Supply

We rely on third-party manufacturers for the supply of active pharmaceutical ingredients.

Accounts Receivable from Government Grants, Net

Property and Equipment, Net

Leases

Impairment of Long-Lived Assets

Goodwill and In-Process Research and Development

Research and Development Expenses

Clinical Trial Expenses

contracts depends on factors such as the successful enrollment or treatment of patients or the completion of other clinical trial milestones.

Share-Based Compensation

Income Taxes

Accumulated Other Comprehensive Income

Accumulated other comprehensive income is the result of unrealized gains and losses on marketable securities.

Net Loss per Common Share/Class A Common Unit Outstanding

Adoption and Pending Adoption of Recent Accounting Pronouncements

The following table provides a brief description of recently issued accounting standards, those adopted in the current period and those not yet adopted:

Standard

Description

Effective Date

Effect on the Financial
Statements or Other
Significant Matters

In March 2020, the FASB issued ASU 2020-03, Codification Improvements to Financial Instruments.

The Guidance makes improvements to financial instrument guidance, including the current expected credit losses guidance.

January 1, 2020

We have adopted the new guidance as of January 1, 2020. The impact of adoption was not material to the consolidated financial statements.

In January 2020, the FASB issued ASU 2020-01, Investments — Equity Securities (Topic 321).

This standard clarifies the interaction between accounting standards related to equity securities (ASC 321), equity method investments (ASC 323), and certain derivatives (ASC 815)

January 1, 2021

January 1, 2020

We have adopted the new guidance as of January 1, 2020. The impact of adoption was not material to the consolidated financial statements.

In December 2019, the FASB issued ASU 2019-12, Simplifying the Accounting for Income Taxes.

January 1, 2020

We have adopted the new guidance as of January 1, 2020. The impact of adoption was not material to the consolidated financial statements.

Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2020

Accounting Policies [Abstract]

Recently Issued Accounting Standards Adopted and Not Yet Adopted

The following table provides a brief description of recently issued accounting standards, those adopted in the current period and those not yet adopted:

Standard

Description

Effective Date

Effect on the Financial
Statements or Other
Significant Matters

In March 2020, the FASB issued ASU 2020-03, Codification Improvements to Financial Instruments.

The Guidance makes improvements to financial instrument guidance, including the current expected credit losses guidance.

January 1, 2020

We have adopted the new guidance as of January 1, 2020. The impact of adoption was not material to the consolidated financial statements.

In January 2020, the FASB issued ASU 2020-01, Investments — Equity Securities (Topic 321).

This standard clarifies the interaction between accounting standards related to equity securities (ASC 321), equity method investments (ASC 323), and certain derivatives (ASC 815)

January 1, 2021

January 1, 2020

We have adopted the new guidance as of January 1, 2020. The impact of adoption was not material to the consolidated financial statements.

In December 2019, the FASB issued ASU 2019-12, Simplifying the Accounting for Income Taxes.

January 1, 2020

We have adopted the new guidance as of January 1, 2020. The impact of adoption was not material to the consolidated financial statements.

Business Combinations (Tables)

12 Months Ended

Dec. 31, 2020

Business Combinations [Abstract]

Schedule of Assets and Liabilities of VIE

Total assets and liabilities of Kalyra as of December 31, 2020 and 2019 are as follows (in thousands):


	December 31,
	2020		2019
Cash and cash equivalents	$	417	$	712
Other current assets	82		21
In-process research and development	8,800		8,800
Goodwill	3,736		3,736
Other long-term assets	—		14
Accounts payable and accrued expenses	83		391
Deferred tax liability	2,463		2,463
Noncontrolling interests	6,705		6,821

Reconciliation Of Equity Attributable to Noncontrolling Interest

The following is a reconciliation of equity (net assets) attributable to the noncontrolling interest (in thousands):


	December 31,
	2020		2019
Noncontrolling interest at beginning of period	$	6,821	$	7,536
Net loss attributable to noncontrolling interest	(116)		(715)
Noncontrolling interest at end of period	$	6,705	$	6,821

- Definition

Tabular disclosure of the significant judgments and assumptions made in determining whether a variable interest (as defined) held by the entity requires the variable interest entity (VIE) (as defined) to be consolidated and (or) disclose information about its involvement with the VIE, individually or in aggregate (as applicable); the nature of restrictions, if any, on the consolidated VIE's assets and on the settlement of its liabilities reported by an entity in its statement of financial position, including the carrying amounts of such assets and liabilities; the nature of, and changes in, the risks associated with involvement in the VIE; how involvement with the VIE affects the entity's financial position, financial performance, and cash flows; the lack of recourse if creditors (or beneficial interest holders) of the consolidated VIE have no recourse to the general credit of the primary beneficiary (if applicable); the terms of arrangements, giving consideration to both explicit arrangements and implicit variable interests, if any, that could require the entity to provide financial support to the VIE, including events or circumstances that could expose the entity to a loss; the methodology used by the entity for determining whether or not it is the primary beneficiary of the variable interest entity; the significant factors considered and judgments made in determining that the power to direct the activities of a VIE that most significantly impact the VIE's economic performance are shared (as defined); the carrying amounts and classification of assets and liabilities of the VIE included in the statement of financial position; the entity's maximum exposure to loss, if any, as a result of its involvement with the VIE, including how the maximum exposure is determined and significant sources of the entity's exposure to the VIE; a comparison of the carrying amounts of the assets and liabilities and the entity's maximum exposure to loss; information about any liquidity arrangements, guarantees, and (or) other commitments by third parties that may affect the fair value or risk of the entity's variable interest in the VIE; whether or not the entity has provided financial support or other support (explicitly or implicitly) to the VIE that it was not previously contractually required to provide or whether the entity intends to provide that support, including the type and amount of the support and the primary reasons for providing the support; and supplemental information the entity determines necessary to provide.

+ References + Details

Fair Value Measurement (Tables)

12 Months Ended

Dec. 31, 2020

Fair Value Disclosures [Abstract]

Components of Available-for-sale Marketable Securities

Available-for-sale marketable securities consisted of the following (in thousands):


	December 31, 2020
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Estimated Fair Value
Commercial paper	$	147,382	$	14	$	(8)	$	147,388
Corporate debt securities	23,576		1		(6)		23,571
US government agencies	81,455		32		(1)		81,486
US Treasury securities	31,105		4		—		31,109
	$	283,518	$	51	$	(15)	$	283,554

Contractual Maturities of Available-for-sale Debt Securities

Contractual maturities of available-for-sale debt securities are as follows (in thousands):


	December 31, 2020
	Estimated Fair Value
Due within one year	$	247,455
After one but within five years	36,099
	$	283,554

Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis


	December 31, 2020						December 31, 2019
	Level 1		Level 2		Total estimated fair value		Level 1		Level 2		Total estimated fair value
Cash equivalents:
Money market funds	$	24,016	$	—	$	24,016	$	62,961	$	—	$	62,961


Corporate debt securities	—		4,999		4,999		—		—		—
Total cash equivalents:	24,016		4,999		29,015		62,961		—		62,961

Available-for-sale marketable securities:
Commercial paper	—		147,388		147,388		—		—		—
Corporate debt securities	—		23,571		23,571		—		—		—
US government agencies	—		81,486		81,486		—		—		—
US Treasury securities	31,109		—		31,109		—		—		—
Total available-for-sale marketable securities:	31,109		252,445		283,554		—		—		—

Total assets measured at fair value	$	55,125	$	257,444	$	312,569	$	62,961	$	—	$	62,961

Prepaid Expenses and Other Assets (Tables)

12 Months Ended

Dec. 31, 2020

Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]

Summary of Prepaid Expenses and Other Assets

Prepaid expenses and other assets consisted of the following (in thousands):


	December 31,
	2020		2019
Prepaid insurance	$	1,021	$	150
Prepaid software licenses and maintenance	563		238
Foreign R&D credit refund	692		—
Prepaid research and development expenses	5,963		2,985
Interest receivable	478		—
Other prepaid expenses	441		266
Total prepaid expenses and other current assets	9,158		3,639
Less long-term portion	2,976		2,134
Total prepaid expenses and other assets, current	$	6,182	$	1,505

Property and Equipment, net (Tables)

12 Months Ended

Dec. 31, 2020

Property, Plant and Equipment [Abstract]

Summary of Property and Equipment, net

Property and equipment, net consisted of the following (in thousands):


	December 31,
	2020		2019
Computer and office equipment	$	529	$	243
Lab equipment	424		401
Leasehold improvements	49		24
Construction in process	347		—
Subtotal	1,349		668
Accumulated depreciation and amortization	(250)		(167)
Property and equipment, net	$	1,099	$	501

Accrued Expenses (Tables)

12 Months Ended

Dec. 31, 2020

Payables and Accruals [Abstract]

Schedule of Accrued Expenses

Accrued expenses consist of the following (in thousands):


	December 31,
	2020		2019
Accrued research and development expenses	$	11,947	$	5,465
Accrued employee expenses	5,649		2,977
Accrued general and administrative expenses	996		1,356
Lease liability	902		781
Income taxes payable	410		—
Other	36		29
Total accrued expenses	$	19,940	$	10,608

Convertible Preferred Units (Tables)

12 Months Ended

Dec. 31, 2020

Equity [Abstract]

Schedule of Temporary Equity


	December 31, 2019
Series	Units Authorized	Shares Issued and Outstanding	Liquidation Value		Carrying Value
Series A convertible preferred units	1,579,309	1,579,309	$	18,320	$	18,226
Series B convertible preferred units	3,523,739	3,523,739	43,800		41,604
Series C convertible preferred units	5,714,300	4,847,106	84,824		81,876
Total	10,817,348	9,950,154	$	146,944	$	141,706

Equity and Share-based Compensation (Tables)

12 Months Ended

Dec. 31, 2020

Equity [Abstract]

Schedule of Share-based Compensation Expense

Total share-based compensation expense related to share based awards was comprised of the following (in thousands):


	Year ended December 31,
	2020		2019
Research and development expense	$	7,296	$	339
General and administrative expense	15,850		278
Total share-based compensation expense	$	23,146	$	617

Share-based compensation expense by type of share-based award (in thousands):


	Year ended December 31,
	2020		2019
Profits interest award units	$	329	$	617
Stock options	6,925		—
RSAs and RSUs	15,892		—
	$	23,146	$	617

Share-based Compensation Expense by Type of Share-based Award


	December 31, 2020
	Unrecognized Expense		Remaining Weighted-Average Recognition Period (Years)
Stock options	$	45,501	3.5
RSAs	2,197		2.5
RSUs	13,078		1.0

Summary of Profits Interest Unites Award Activity

The following table provides a summary of the profits interest units award activity under the Plan. The amounts include profits interest units granted to both employees and non-employees:


	Number of Units	Weighted Average Fair Value
Outstanding at December 31, 2018	1,612,311	$	1.56
Granted	1,095,545	$	2.73
Forfeited	(37,188)	$	1.62
Outstanding at December 31, 2019	2,670,668	$	2.04
Granted	70,000	$	3.06
Cancelled upon conversion	(2,740,668)	$	2.07
Outstanding at December 31, 2020	—	$	—

Schedule of Valuation Assumptions

The fair value of the profits interest award units was estimated using an option pricing model with the following assumptions:


	Year ended December 31,
	2020	2019
Members’ equity value (in thousands)	$271,207	$197,041 - $271,207
Threshold amounts (in thousands)	$309,824	$143,800 - $309,824
Risk-free rate	1.5%	1.5%
Volatility	75.0%	75.0%
Time to liquidity (in years)	1.1	1.1 - 1.8
Lack of marketability discount	26.5%	18.8% - 26.4%
Grant date fair value	$3.06	$1.88 - $3.06

The fair value of the stock options granted during the year ended December 31, 2020 was determined with the following assumptions:


			Year ended December 31,
			2020
Expected volatility			76.4% - 78.7%
Average expected term (in years)			1.0 - 6.0
Risk-free interest rate			0.1% - 0.5%
Expected dividend yield			—%

Summary of Stock option Activity

The following table provides a summary of the stock option activity under the 2020 Plan. The amounts include incentive units granted to both employees and non-employees (in thousands, unless otherwise noted):


	Number of Shares	Weighted Average Exercise Price		Weighted Average Remaining Contractual Term (Years)	Aggregate Intrinsic Value
Outstanding at December 31, 2019	—
Granted	3,137,746
Cancelled	(16,525)
Outstanding at December 31, 2020	3,121,221	$	25.45	9.4	$82,691
Vested and expected to vest at December 31, 2020	3,121,221	$	25.45	9.4	$82,691
Exercisable at December 31, 2020	42,691	$	22.07	9.3	$1,275

Summary of RSA Activity

The following table provides a summary of the RSA activity. The amounts include incentive units granted to both employees and non-employees:


	Number of Shares	Weighted Average Grant Date Fair Value
Outstanding at December 31, 2019	—	$	—
Conversion of unvested profit interest award units into RSAs	1,160,277	$	2.91
Vested	(409,259)	$	2.70
Forfeited	(8,607)	$	2.70
Outstanding at December 31, 2020	742,411	$	3.03

Summary of RUS Activity

The following table provides a summary of the restricted stock unit ("RSU") activity under the 2020 Plan. The amounts include incentive units granted to both employees and non-employees:


	Number of Shares	Weighted Average Grant Date Fair Value
Outstanding at December 31, 2019	—	$	—
Granted	1,145,875	$	23.75
Vested	(426,625)	$	23.75
Forfeited	(44,493)	$	23.75
Outstanding at December 31, 2020	674,757	$	23.75

Commitment and Contingencies (Tables)

12 Months Ended

Dec. 31, 2020

Commitments and Contingencies Disclosure [Abstract]

Summary of Operating Lease Terms

The following table presents the weighted average remaining lease term and weighted average discount rates related to our operating leases as of December 31, 2020:


Weighted average remaining lease term (in years)			1.8
Weighted average discount rate			10.7%

Schedule of Future Minimum Operating Lease Payments

Approximate annual future minimum operating lease payments as of December 31, 2020 are as follows (in thousands):


Year	Amount
2021	$	1,052
2022	1,005
2023	187



Total minimum lease payments:	2,244
Less: imputed interest	245
Total operating lease liabilities	1,999
Less: current portion	902
Lease liability, net of current portion	$	1,097

The expected future minimum lease obligation are as follows (in thousands):


Year-ending December 31,	Payment Amount
2021	$	—
2022	1,458
2023	1,458
2024	1,459
2025	1,782
Thereafter	11,970
Total minimum lease payments:	$	18,127

Income Taxes (Tables)

12 Months Ended

Dec. 31, 2020

Income Tax Disclosure [Abstract]

Schedule of Income before Income Tax, Domestic and Foreign

Pretax losses were generated by both domestic and foreign operations as follows (in thousands):


	Year ended December 31,
	2020		2019
U.S. net loss before income taxes	$	(112,827)	$	(46,363)
Foreign net loss before income taxes	(5,277)		—
Net loss before income taxes	$	(118,104)	$	(46,363)

Schedule of Components of Income Tax Expense (Benefit)

The following table presents the current and deferred income tax provision (benefit) for federal and state income taxes (in thousands):


	Year ended December 31,
	2020		2019
Current tax provision:
Federal	$	—	$	—
State	16		15
Foreign	410		—
Total current tax provision	426		15
Deferred tax provision:
Federal	—		—
State	—		—
Foreign	18		—
Total deferred tax provision	18		—
Total provision for income taxes:	$	444	$	15

Schedule of Effective Income Tax Rate Reconciliation

The following table is a reconciliation of the expected tax computed at the U.S. statutory federal income tax rate to the total provision for income taxes (in thousands):


	Year ended December 31,
	2020				2019
Expected tax at 21%	$	(24,802)	21.0	%	$	(9,730)	21.0	%
State income tax, net of federal tax	273		(0.3)	%	(3,167)		6.8	%
Limited liability company loss	—		—	%	4		—	%
Non-deductible expenses	—		—	%	164		(0.3)	%
Research credits	(4,025)		3.4	%	(1,424)		3.1	%
Share-based compensation	(1,718)		1.5	%	—		—	%
Other	146		(0.1)	%	(2)		—	%
Section 162(m) limitations	2,956		(2.5)	%	—		—	%
Change in valuation allowance	27,614		(23.4)	%	14,170		(30.6)	%
Provision for income taxes	$	444	(0.4)	%	$	15	0.0	%

Schedule of Deferred Tax Assets and Liabilities

Significant components of our net deferred tax asset or liability are as follows (in thousands):


	December 31,
	2020		2019
Deferred tax assets
Net operating loss	$	45,730	$	25,053
Compensation	892		148
Share-based compensation	1,691		—
ASC 842 lease liability	425		693
Accrued liabilities	632		1
Research credits	7,528		3,503
Total gross deferred tax assets	56,898		29,398
Valuation allowance	(56,261)		(28,647)
Net deferred tax assets	637		751
Deferred tax liabilities
Depreciable assets	(145)		(97)
ASC 842 right of use asset	(502)		(654)
In-process research and development	(2,463)		(2,463)
Other	(7)		—
Deferred tax liabilities	(3,117)		(3,214)
Net deferred tax liabilities	$	(2,480)	$	(2,463)

Schedule of Unrecognized Tax Benefits Roll Forward

The following table reconciles the beginning and ending amount of unrecognized tax benefits for the years ended December 31, 2020 and 2019 (in thousands):


	December 31,
	2020		2019
Gross unrecognized tax benefits at the beginning of the year	$	1,124	$	741
Increase related to current year tax positions	661		383
Increase related to prior year tax positions	197		—
Decrease related to prior year tax positions	(50)		—
Gross unrecognized tax benefits at end of the year	$	1,932	$	1,124

Net Loss Per Common Share/Class A Common Unit (Tables)

12 Months Ended

Dec. 31, 2020

Earnings Per Share [Abstract]

Schedule of Basic and Diluted Net Loss Per Unit

Basic and diluted net loss per common share/Class A common unit were calculated as follows (in thousands except per share amounts):


	Year ended December 31,
	2020		2019
Numerator:
Net loss attributable to Zentalis	$	(117,841)	$	(45,663)
Denominator:
Weighted average number of common shares/Class A common units outstanding, basic and diluted	28,113		5,597
Net loss per common share	$	(4.19)	$	—
Net loss per Class A common unit	$	—	$	(8.16)

Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Unit


	Year ended December 31,
	2020	2019
Preferred units, as if converted to Class A common units	—	9,950
Incentive units—Class B common units	—	2,671
Outstanding stock options	3,121	—
Unvested RSAs	742	—
Unvested RSUs	675	—
	4,538	12,621

Selected Quarterly Financial Data (Unaudited) (Tables)

12 Months Ended

Dec. 31, 2020

Quarterly Financial Information Disclosure [Abstract]

Schedule of Quarterly Results

Selected quarterly financial data is as follows:


	Three months ended
	3/31/2020		6/30/2020		9/30/2020				12/31/2020
Operating Expenses
Research and development	$	13,258	$	17,452	$	24,670			$	29,521
General and administrative	3,141		$	9,924	$	10,097			10,724
Total operating expenses	16,399		27,376		34,767				40,245
Operating loss	(16,399)		(27,376)		(34,767)				(40,245)
Other Income (Expense)
Investment and other income (expense), net	164		$	84	$	120			315
Net loss before income taxes	(16,235)		(27,292)		(34,647)				(39,930)
Income tax expense	—		—		$	18			426
Net loss	(16,235)		(27,292)		(34,665)		$	—	(40,356)
Net loss attributable to noncontrolling interests	(109)		(435)		(110)				(53)
Net loss attributable to Zentalis	$	(16,126)	$	(26,857)	$	(34,555)			$	(40,303)
Net loss per common share outstanding, basic and diluted			$	(0.78)	$	(0.91)			$	(1.01)
Net loss per Class A common unit outstanding, basic and diluted	$	(2.88)
Common shares/units used in computing net loss per share/Class A common unit, basic and diluted	5,601		34,353		37,959				39,936


	Three months ended
	3/31/2019		6/30/2019		9/30/2019				12/31/2019
Operating Expenses
Research and development	$	7,089	$	8,689	$	10,739			$	11,869
General and administrative	1,633		1,946		1,844				3,036
Total operating expenses	8,722		10,635		12,583				14,905
Operating loss	(8,722)		(10,635)		(12,583)				(14,905)
Other Income (Expense)
Investment and other income (expense), net	62		49		12				359
Net loss before income taxes	(8,660)		(10,586)		(12,571)				(14,546)
Income tax expense	3		11		1				—
Net loss	(8,663)		(10,597)		(12,572)		$	—	(14,546)
Net loss attributable to noncontrolling interests	(320)		(127)		(228)				(40)
Net loss attributable to Zentalis	$	(8,343)	$	(10,470)	$	(12,344)			$	(14,506)
Net loss per Class A common unit outstanding, basic and diluted	$	(1.49)	$	(1.87)	$	(2.20)			$	(2.59)
Common units used in computing net loss per Class A common unit, basic and diluted	5,594		5,594		5,599				5,601

Subsequent Events (Tables)

12 Months Ended

Dec. 31, 2020

Subsequent Events [Abstract]

Schedule of Future Minimum Operating Lease Payments

Approximate annual future minimum operating lease payments as of December 31, 2020 are as follows (in thousands):


Year	Amount
2021	$	1,052
2022	1,005
2023	187



Total minimum lease payments:	2,244
Less: imputed interest	245
Total operating lease liabilities	1,999
Less: current portion	902
Lease liability, net of current portion	$	1,097

The expected future minimum lease obligation are as follows (in thousands):


Year-ending December 31,	Payment Amount
2021	$	—
2022	1,458
2023	1,458
2024	1,459
2025	1,782
Thereafter	11,970
Total minimum lease payments:	$	18,127

Organization and Business (Details) $ / shares in Units, $ in Thousands						1 Months Ended	2 Months Ended	12 Months Ended
	Aug. 03, 2020 USD ($) $ / shares shares	May 19, 2020 USD ($) executive	Apr. 07, 2020 USD ($) $ / shares shares	Apr. 02, 2020 $ / shares shares	Dec. 21, 2017	Sep. 30, 2015 USD ($)	Mar. 31, 2016 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Class of Stock [Line Items]
Exchange ratio					1
Proceeds from issuance of common stock in initial public offering, net			$ 190,000					$ 172,482	$ 0
Issuance fees and expenses			17,600
Contributions from noncontrolling interest owners		$ 20,000						$ 18,424
Zentera Stock Plan
Class of Stock [Line Items]
Number of executives entering restricted stock agreement \| executive		2
Unvested RSAs \| Zentera Stock Plan
Class of Stock [Line Items]
Restricted stock vesting period (in years)		4 years
Zentera Sublicenses
Class of Stock [Line Items]
Ownership percentage								60.20%
IPO
Class of Stock [Line Items]
Share price (in dollars per sharee) \| $ / shares				$ 18.00
Proceeds from issuance of common stock in initial public offering, net			190,000
Issuance fees and expenses			$ 17,600
Follow-On Offering
Class of Stock [Line Items]
Gross proceeds from issuance of common stock	$ 166,000
Expenses and Fees from the Issuance of Common Stock	$ 10,800
Common Stock \| IPO
Class of Stock [Line Items]
Share price (in dollars per sharee) \| $ / shares			$ 18.00
Number of shares converted (in shares) \| shares				25,288,854
Number of shares issued and sold (in shares) \| shares			10,557,000
Common Stock \| Underwriters
Class of Stock [Line Items]
Share price (in dollars per sharee) \| $ / shares			$ 18.00
Number of shares issued and sold (in shares) \| shares	618,750		1,377,000
Common Stock \| Follow-On Offering
Class of Stock [Line Items]
Share price (in dollars per sharee) \| $ / shares	$ 35.00
Number of shares issued and sold (in shares) \| shares	4,743,750
Unvested RSAs \| IPO
Class of Stock [Line Items]
Number of shares converted (in shares) \| shares				1,160,277
Series A Preferred Units
Class of Stock [Line Items]
Issuance fees and expenses		$ 1,600				$ 100	$ 39

Summary of Significant Accounting Policies (Details) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 21, 2017
Variable Interest Entity [Line Items]
Restricted cash	$ 1,320,000	$ 243,000
Allowance for credit loss	$ 0	$ 0
Operating lease, liability, current, balance sheet location [Extensible List]	us-gaap:AccruedLiabilitiesCurrent	us-gaap:AccruedLiabilitiesCurrent
Operating lease, liability, noncurrent, balance sheet location [Extensible List]	us-gaap:OtherLiabilitiesNoncurrent	us-gaap:OtherLiabilitiesNoncurrent
Minimum \| Equipment
Variable Interest Entity [Line Items]
Property, plant and equipment, useful life (years)	3 years
Maximum
Variable Interest Entity [Line Items]
Property, plant and equipment, useful life (years)	5 years
Kalyra Pharmaceuticals, Inc.
Variable Interest Entity [Line Items]
Ownership percentage			25.00%

Business Combinations - Narrative (Details) - Kalyra Pharmaceuticals, Inc. $ in Millions	Dec. 21, 2017 USD ($)
Variable Interest Entity [Line Items]
Cash payments to acquire interest	$ 4.5
Ownership percentage	25.00%

Business Combinations - Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Variable Interest Entity [Line Items]
Cash and cash equivalents	$ 54,951	$ 67,246
In-process research and development	8,800	8,800
Goodwill	3,736	3,736
Deferred tax liability	2,480	2,463
VIE, Primary Beneficiary
Variable Interest Entity [Line Items]
Cash and cash equivalents	417	712
Other current assets	82	21
In-process research and development	8,800	8,800
Goodwill	3,736	3,736
Other long-term assets	0	14
Accounts payable and accrued expenses	83	391
Deferred tax liability	2,463	2,463
Noncontrolling interests	$ 6,705	$ 6,821	$ 7,536

Business Combinations - Rollforward of Noncontrolling Interest (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Net loss attributable to noncontrolling interests	$ (53)	$ (110)	$ (435)	$ (109)	$ (40)	$ (228)	$ (127)	$ (320)	$ (707)	$ (715)
VIE, Primary Beneficiary
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Noncontrolling interest at beginning of period				$ 6,821				$ 7,536	6,821	7,536
Net loss attributable to noncontrolling interests									(116)	(715)
Noncontrolling interest at end of period	$ 6,705				$ 6,821				$ 6,705	$ 6,821

- Definition

Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which is directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent (that is, noncontrolling interest, previously referred to as minority interest).

+ References + Details

Fair Value Measurement - Components of Available-for-sale Marketable Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 283,518
Gross Unrealized Gains	51
Gross Unrealized Losses	(15)
Debt securities, available-for-sale, fair value	283,554	$ 0
Commercial paper
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	147,382
Gross Unrealized Gains	14
Gross Unrealized Losses	(8)
Debt securities, available-for-sale, fair value	147,388	0
Corporate debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	23,576
Gross Unrealized Gains	1
Gross Unrealized Losses	(6)
Debt securities, available-for-sale, fair value	23,571	0
US government agencies
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	81,455
Gross Unrealized Gains	32
Gross Unrealized Losses	(1)
Debt securities, available-for-sale, fair value	81,486	0
US Treasury securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	31,105
Gross Unrealized Gains	4
Gross Unrealized Losses	0
Debt securities, available-for-sale, fair value	$ 31,109	$ 0

Fair Value Measurement - Narrative (Details) $ in Thousands	Dec. 31, 2020 USD ($) security
Fair Value Disclosures [Abstract]
Number of available-for-sale securities in unrealized loss position \| security	17
Debt securities fair market value	$ 69,500
Fair value of available-for-sale securities in unrealized loss position	$ 15,000

Fair Value Measurement - Contractual Maturities of Available-for-sale Securities (Details) $ in Thousands	Dec. 31, 2020 USD ($)
Fair Value Disclosures [Abstract]
Due within one year	$ 247,455
After one but within five years	36,099
Amortized Cost	$ 283,554

Fair Value Measurement - Fair Value of Assets Measured on a Recurring Basis (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Cash equivalents	$ 29,015	$ 62,961
Marketable securities, available for sale	283,554	0
Total fair value of assets	312,569	62,961
Level 1
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Cash equivalents	24,016	62,961
Marketable securities, available for sale	31,109	0
Total fair value of assets	55,125	62,961
Level 2
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Cash equivalents	4,999	0
Marketable securities, available for sale	252,445	0
Total fair value of assets	257,444	0
Commercial paper
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Marketable securities, available for sale	147,388	0
Commercial paper \| Level 1
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Marketable securities, available for sale	0	0
Commercial paper \| Level 2
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Marketable securities, available for sale	147,388	0
Corporate debt securities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Marketable securities, available for sale	23,571	0
Corporate debt securities \| Level 1
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Marketable securities, available for sale	0	0
Corporate debt securities \| Level 2
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Marketable securities, available for sale	23,571	0
US government agencies
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Marketable securities, available for sale	81,486	0
US government agencies \| Level 1
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Marketable securities, available for sale	0	0
US government agencies \| Level 2
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Marketable securities, available for sale	81,486	0
US Treasury securities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Marketable securities, available for sale	31,109	0
US Treasury securities \| Level 1
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Marketable securities, available for sale	31,109	0
US Treasury securities \| Level 2
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Marketable securities, available for sale	0	0
Money market funds
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Cash equivalents	24,016	62,961
Money market funds \| Level 1
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Cash equivalents	24,016	62,961
Money market funds \| Level 2
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Cash equivalents	0	0
Corporate debt securities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Cash equivalents	4,999	0
Corporate debt securities \| Level 1
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Cash equivalents	0	0
Corporate debt securities \| Level 2
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Cash equivalents	$ 4,999	$ 0

Prepaid Expenses and Other Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Prepaid insurance	$ 1,021	$ 150
Prepaid software licenses and maintenance	563	238
Foreign R&D credit refund	692	0
Prepaid research and development expenses	5,963	2,985
Interest receivable	478	0
Other prepaid expenses	441	266
Total prepaid expenses and other current assets	9,158	3,639
Less long-term portion	2,976	2,134
Total prepaid expenses and other assets, current	$ 6,182	$ 1,505

Property and Equipment, net - Summary (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Property, Plant and Equipment [Line Items]
Subtotal	$ 1,349	$ 668
Accumulated depreciation and amortization	(250)	(167)
Property and equipment, net	1,099	501
Computer and office equipment
Property, Plant and Equipment [Line Items]
Subtotal	529	243
Lab equipment
Property, Plant and Equipment [Line Items]
Subtotal	424	401
Leasehold improvements
Property, Plant and Equipment [Line Items]
Subtotal	49	24
Construction in process
Property, Plant and Equipment [Line Items]
Subtotal	$ 347	$ 0

Property and Equipment, net - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Property, Plant and Equipment [Abstract]
Depreciation and amortization	$ 160	$ 111

Accrued Expenses (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Payables and Accruals [Abstract]
Accrued research and development expenses	$ 11,947	$ 5,465
Accrued employee expenses	5,649	2,977
Accrued general and administrative expenses	996	1,356
Lease liability	902	781
Income taxes payable	410	0
Other	36	29
Total accrued expenses	$ 19,940	$ 10,608

Convertible Preferred Units - Narrative (Details) - USD ($)			1 Months Ended				2 Months Ended	3 Months Ended	8 Months Ended	12 Months Ended
	May 19, 2020	Apr. 07, 2020	Feb. 29, 2020	Sep. 30, 2019	Dec. 31, 2017	Sep. 30, 2015	Mar. 31, 2016	Apr. 02, 2020	Aug. 31, 2018	Dec. 31, 2020	Dec. 31, 2019
Class of Stock [Line Items]
Shares issued (in shares)											9,950,154,000
Net proceeds from issuance of convertible preferred units										$ 14,228,000	$ 81,876,000
Issuance costs of financing		$ 17,600,000
Dividends declared (in dollars per share)								$ 0
Automatic conversion feature, minimum gross cash proceeds received in a public offering										$ 75,000,000.0
Series A Preferred Units
Class of Stock [Line Items]
Convertible preferred units issued (in shares)						1,293,104
Par value per share (in dollars per share)						$ 11.60	$ 11.60
Shares issued (in shares)							286,205				1,579,309,000
Gross proceeds from issuance of convertible preferred units						$ 15,000,000.0	$ 3,300,000
Net proceeds from issuance of convertible preferred units						14,900,000
Issuance costs of financing	$ 1,600,000					$ 100,000	$ 39,000
Conversion price (in dollars per share)										$ 11.60
Liquidation preference (in dollars per share)										11.60
Series B Preferred Units
Class of Stock [Line Items]
Par value per share (in dollars per share)					$ 12.43				$ 12.43
Shares issued (in shares)					2,735,320				788,419		3,523,739,000
Gross proceeds from issuance of convertible preferred units					$ 34,000,000.0				$ 9,800,000
Net proceeds from issuance of convertible preferred units					32,100,000				9,500,000
Issuance costs of financing					$ 1,900,000				$ 300,000
Conversion price (in dollars per share)										12.43
Liquidation preference (in dollars per share)										12.43
Series C Preferred Units
Class of Stock [Line Items]
Par value per share (in dollars per share)			$ 17.50	$ 17.50						17.50	$ 17.50
Shares issued (in shares)			867,194	4,847,106							4,847,106,000
Gross proceeds from issuance of convertible preferred units			$ 15,200,000	$ 84,800,000
Net proceeds from issuance of convertible preferred units			14,200,000	81,900,000
Issuance costs of financing			$ 1,000,000.0	$ 2,900,000
Conversion price (in dollars per share)										17.50
Liquidation preference (in dollars per share)										$ 17.50

Convertible Preferred Units - Schedule of Units Authorized, Issued, and Outstanding (Details) - USD ($) $ in Thousands	Feb. 29, 2020	Dec. 31, 2019	Sep. 30, 2019	Aug. 31, 2018	Dec. 31, 2017	Mar. 31, 2016
Class of Stock [Line Items]
Units authorized (in shares)		10,817,348,000
Shares issued (in shares)		9,950,154,000
Shares outstanding (in shares)		9,950,154,000
Liquidation Value		$ 146,944
Carrying Value		$ 141,706
Series A Preferred Units
Class of Stock [Line Items]
Units authorized (in shares)		1,579,309,000
Shares issued (in shares)		1,579,309,000				286,205
Shares outstanding (in shares)		1,579,309,000
Liquidation Value		$ 18,320
Carrying Value		$ 18,226
Series B Preferred Units
Class of Stock [Line Items]
Units authorized (in shares)		3,523,739,000
Shares issued (in shares)		3,523,739,000		788,419	2,735,320
Shares outstanding (in shares)		3,523,739,000
Liquidation Value		$ 43,800
Carrying Value		$ 41,604
Series C Preferred Units
Class of Stock [Line Items]
Units authorized (in shares)		5,714,300,000
Shares issued (in shares)	867,194	4,847,106,000	4,847,106
Shares outstanding (in shares)		4,847,106,000
Liquidation Value		$ 84,824
Carrying Value		$ 81,876

Equity and Share-based Compensation - Narrative (Details) $ / shares in Units, $ in Thousands					1 Months Ended			2 Months Ended	8 Months Ended	12 Months Ended
	Aug. 03, 2020 USD ($) $ / shares shares	May 19, 2020 USD ($)	Apr. 07, 2020 USD ($) $ / shares shares	Apr. 02, 2020 $ / shares shares	Apr. 30, 2020 shares	Dec. 31, 2017 USD ($) shares	Sep. 30, 2015 USD ($)	Mar. 31, 2016 USD ($)	Aug. 31, 2018 USD ($)	Dec. 31, 2020 USD ($) $ / shares shares	Dec. 31, 2019 USD ($) shares	Mar. 15, 2021 shares	Sep. 30, 2019 shares	Dec. 21, 2017 shares
Class of Stock [Line Items]
Common stock issued (in shares)						5,187,554				41,040,286
Common stock outstanding (in shares)						5,187,554				41,040,286
Common stock subject to future vesting provisions (in shares)						406,831
Common stock, shares authorized (in shares)				250,000,000						250,000,000
Common stock, par value (in dollars per share) \| $ / shares				$ 0.001						$ 0.001
Preferred stock, shares authorized (in shares)				10,000,000						10,000,000
Preferred stock, par value (in dollars per share) \| $ / shares				$ 0.001						$ 0.001
Proceeds from issuance of common stock in initial public offering, net \| $			$ 190,000							$ 172,482	$ 0
Issuance fees and expenses \| $			17,600
Options, weighted average grant date fair value (dollars per share) \| $ / shares										$ 16.79
IPO
Class of Stock [Line Items]
Share price (in dollars per sharee) \| $ / shares				$ 18.00
Proceeds from issuance of common stock in initial public offering, net \| $			190,000
Issuance fees and expenses \| $			$ 17,600
Follow-On Offering
Class of Stock [Line Items]
Expenses and Fees from the Issuance of Common Stock \| $	$ 10,800
Gross proceeds from issuance of common stock \| $	$ 166,000
2020 ESPP
Class of Stock [Line Items]
Employee Stock Purchase Program (ESPP), Number of shares available, initial term in calculation (shares)					450,000
Employee Stock Purchase Program (ESPP), Number of shares available, percentage term in calculation (percent)					0.01
Employee Stock Purchase Program (ESPP), Number of shares available, other term in calculation (shares)					1,500,000
Amended 2020 ESPP \| Subsequent Event
Class of Stock [Line Items]
Employee Stock Purchase Plan (ESPP), shares in ESPP reserve												2,000,000
Series A Preferred Units
Class of Stock [Line Items]
Preferred units authorized (in shares)						1,638,000
Issuance fees and expenses \| $		$ 1,600					$ 100	$ 39
Series B Preferred Units
Class of Stock [Line Items]
Preferred units authorized (in shares)						3,621,000
Issuance fees and expenses \| $						$ 1,900			$ 300
Class A Common Units
Class of Stock [Line Items]
Common units, authorized (in shares)						15,000,000					20,000,000		20,000,000
Stock issued (in shares)										0	7,093
Common units subject to future vesting conditions (in shares)										0	9,572
Class B Common Units
Class of Stock [Line Items]
Common units, authorized (in shares)						872,620					3,458,522		3,458,522
Stock issued upon conversion of units (in shares)						703,000
Class B Common Units \| The Plan
Class of Stock [Line Items]
Shares authorized to be issued under plan (in shares)														3,458,522
Class B Common Units \| The 2020 Plan \| Maximum
Class of Stock [Line Items]
Shares authorized to be issued under plan (in shares)					1,250,000
Common Stock \| Corporate Conversion
Class of Stock [Line Items]
Stock issued (in shares)				0
Common Stock \| IPO
Class of Stock [Line Items]
Stock issued upon conversion of units (in shares)				25,288,854
Stock issued (in dollars per share) \| $ / shares			$ 18.00
Number of shares issued and sold (in shares)			10,557,000
Share price (in dollars per sharee) \| $ / shares			$ 18.00
Common Stock \| Underwriters
Class of Stock [Line Items]
Number of shares issued and sold (in shares)	618,750		1,377,000
Share price (in dollars per sharee) \| $ / shares			$ 18.00
Common Stock \| Follow-On Offering
Class of Stock [Line Items]
Number of shares issued and sold (in shares)	4,743,750
Share price (in dollars per sharee) \| $ / shares	$ 35.00
Common Stock \| The 2020 Plan
Class of Stock [Line Items]
Shares authorized to be issued under plan (in shares)					5,600,000
Percent of common stock outstanding used as threshold to calculate shares available for issuance					5.00%
Unvested RSAs \| IPO
Class of Stock [Line Items]
Stock issued upon conversion of units (in shares)				1,160,277
Outstanding stock options
Class of Stock [Line Items]
Generally expected vesting term of the option contract (in years)										10 years

Equity and Share-based Compensation - Share-based Compensation (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation expense	$ 23,146	$ 617
Research and development expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation expense	7,296	339
General and administrative expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation expense	$ 15,850	$ 278

Equity and Share-based Compensation - Share-based Compensation Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation expense	$ 23,146	$ 617
Profit interest award units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation expense	329	617
Outstanding stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation expense	6,925	0
RSAs and RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation expense	$ 15,892	$ 0

Equity and Share-based Compensation - Unrecognized Compensation Cost (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2020 USD ($)
Outstanding stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized expense, stock options	$ 45,501
Remaining Weighted-Average Recognition Period (years)	3 years 6 months
Unvested RSAs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized expense, other than options	$ 2,197
Remaining Weighted-Average Recognition Period (years)	2 years 6 months
Unvested RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized expense, other than options	$ 13,078
Remaining Weighted-Average Recognition Period (years)	1 year

Equity and Share-based Compensation - Fair Value Assumptions for Profit Interest Awards (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Members’ equity value (in thousands)	$ 308,582	$ (80,106)
Profit Interest Awards
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Members’ equity value (in thousands)	271,207	197,041
Threshold amounts (in thousands)	$ 309,824	$ 143,800
Risk free rate (as a percent)	1.50%	1.50%
Volatility (as a percent)	75.00%	75.00%
Time to liquidity (in years)	1 year 1 month 6 days
Lack of marketability discount (as a percent)	26.50%
Grant date fair value (in dollars per share)	$ 3,060.00	$ 3.06	$ 2.73
Profit Interest Awards \| Minimum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Time to liquidity (in years)		1 year 1 month 6 days
Lack of marketability discount (as a percent)		18.80%
Grant date fair value (in dollars per share)		$ 1,880
Profit Interest Awards \| Maximum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Time to liquidity (in years)		1 year 9 months 18 days
Lack of marketability discount (as a percent)		26.40%
Grant date fair value (in dollars per share)		$ 3,060.00

Equity and Share-based Compensation - Summary of Option Activity (Details) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2020 USD ($) $ / shares shares
Stock Option Activity
Outstanding at December 31, 2019 (in shares)	0
Options granted (in shares)	3,137,746
Options cancelled (in shares)	(16,525)
Outstanding at December 31, 2020 (in shares)	3,121,221
Stock Options Weighted Average Exercise Price
Options outstanding, Weighted average exercise price per share - December 31, 2020 (in $ per share) \| $ / shares	$ 25.45
Stock Option Activity, Additional Disclosures
Options outstanding, Weighted average remaining contractual term	9 years 4 months 24 days
Options outstanding, Aggregate intrinsic value (in USD) \| $	$ 82,691
Options vested and expected to vest, Number of options (in shares)	3,121,221
Options vested and expected to vest, Weighted average exercise price per share (in $ per share) \| $ / shares	$ 25.45
Options vested and expected to vest, Weighted average remaining contractual term	9 years 4 months 24 days
Options vested and expected to vest, Aggregate intrinsic value (in USD) \| $	$ 82,691
Options exercisable, Number of options (in shares)	42,691
Options exercisable, Weighted average exercise price per share (in $ per share) \| $ / shares	$ 22.07
Options exercisable, Weighted average remaining contractual term	9 years 3 months 18 days
Options exercisable, Aggregate intrinsic value (in USD) \| $	$ 1,275

Equity and Share-based Compensation - Fair Value Assumptions for Stock Options (Details) - Outstanding stock options	12 Months Ended
	Dec. 31, 2020
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Expected dividend yield	0.00%
Minimum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Volatility (as a percent)	76.40%
Average expected term (in years)	1 year
Risk free rate (as a percent)	0.10%
Maximum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Volatility (as a percent)	78.70%
Average expected term (in years)	6 years
Risk free rate (as a percent)	0.50%

Equity and Share-based Compensation - Equity instruments Other than Options (Details) - $ / shares	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Profit Interest Awards
Activity
Outstanding at the beginning of the period (in shares)	2,670,668	1,612,311
Granted (in shares)		70,000	1,095,545
Forfeited (in shares)		(2,740,668)	(37,188)
Outstanding at the end of the period (in shares)	0	2,670,668	1,612,311
Weighted Average Grant Date Fair Value
Outstanding, Weighted average grant date fair value beginning of the period (in dollars per share)	$ 2.04	$ 1.56
Granted, (in dollars per share)	3,060.00	3.06	$ 2.73
Forfeited (in dollars per share)		2.07	1.62
Outstanding, Weighted average grant date fair value end of the period (in dollars per share)	$ 0	$ 2.04	$ 1.56
Restricted Stock Awards (RSAs)
Activity
Outstanding at the beginning of the period (in shares)	0
Conversion of unvested profit interest award units into RSAs (shares)	1,160,277
Vested (shares)	(409,259)
Forfeited (in shares)	(8,607)
Outstanding at the end of the period (in shares)	742,411	0
Weighted Average Grant Date Fair Value
Outstanding, Weighted average grant date fair value beginning of the period (in dollars per share)	$ 0
Conversion of unvested profit interest award units into RSAs (in dollars per share)	2.91
Vested (in dollars per share)	2.70
Forfeited (in dollars per share)	2.70
Outstanding, Weighted average grant date fair value end of the period (in dollars per share)	$ 3.03	$ 0
Restricted Stock Units (RSUs)
Activity
Outstanding at the beginning of the period (in shares)	0
Granted (in shares)	1,145,875
Vested (shares)	(426,625)
Forfeited (in shares)	(44,493)
Outstanding at the end of the period (in shares)	674,757	0
Weighted Average Grant Date Fair Value
Outstanding, Weighted average grant date fair value beginning of the period (in dollars per share)	$ 0
Granted, (in dollars per share)	23.75
Vested (in dollars per share)	23.75
Forfeited (in dollars per share)	23.75
Outstanding, Weighted average grant date fair value end of the period (in dollars per share)	$ 23.75	$ 0

Commitment and Contingencies - Summary of Operating Lease Terms (Details)	Dec. 31, 2020
Commitments and Contingencies Disclosure [Abstract]
Weighted average remaining lease term (in years)	1 year 9 months 18 days
Weighted average discount rate	10.70%

Commitment and Contingencies - Future Minimum Lease Payments (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Commitments and Contingencies Disclosure [Abstract]
2021	$ 1,052
2022	1,005
2023	187
Total minimum lease payments:	2,244
Less: imputed interest	245
Total operating lease liabilities	1,999
Lease liability	902	$ 781
Lease liability, net of current portion	$ 1,097

Commitment and Contingencies - Narrative (Details) $ in Millions	1 Months Ended	12 Months Ended
	Nov. 30, 2021 ft²	Dec. 31, 2020 USD ($) ft² option	Dec. 31, 2019 USD ($)
Lessee, Lease, Description [Line Items]
Operating lease, rent expense \| $		$ 1.1	$ 0.8
Operating lease payments \| $		1.0	$ 0.7
Total minimum lease payments on leases not yet commenced \| $		$ 85.6
San Diego \| Building
Lessee, Lease, Description [Line Items]
Area of leased space (in square feet)		11,121
Potential annual increase to lease rent (percent)		0.030
Area of subleased space (in square feet)		2,333
Number of renewal options \| option		2
Operating lease, renewal term (in years)		5 years
New York \| Building
Lessee, Lease, Description [Line Items]
Area of leased space (in square feet)		4,800
Potential annual increase to lease rent (percent)		0.030
Forecast \| San Diego \| Building
Lessee, Lease, Description [Line Items]
Potential annual increase to lease rent (percent)	0.030
Lease not yet commenced, area of leased space (in square feet)	117,929
Forecast \| San Diego \| Temporary Leased Building
Lessee, Lease, Description [Line Items]
Lease not yet commenced, area of leased space (in square feet)	13,251

Income Taxes - Net Loss before Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Income Tax Disclosure [Abstract]
U.S. net loss before income taxes	$ (112,827)	$ (46,363)
Foreign net loss before income taxes	(5,277)	0
Net loss before income taxes	$ (118,104)	$ (46,363)

Income Taxes - Provision/Benefit (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019
Current tax provision:
Federal									$ 0	$ 0
State									16	15
Foreign									410	0
Total current tax provision									426	15
Deferred tax provision:
Federal									0	0
State									0	0
Foreign									18	0
Total deferred tax provision									18	0
Total provision for income taxes:	$ 426	$ 18	$ 0	$ 0	$ 0	$ 1	$ 11	$ 3	$ 444	$ 15

Income Taxes - Effective Income Tax Reconciliation (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019
Effective Income Tax Rate Reconciliation, Amount
Expected tax at 21%									$ (24,802)	$ (9,730)
State income tax, net of federal tax									273	(3,167)
Limited liability company loss									0	4
Non-deductible expenses									0	164
Research credits									(4,025)	(1,424)
Share-based compensation									(1,718)	0
Other									$ 146	$ (2)
Section 162(m) limitations									(0.025)	0
Change in valuation allowance									$ 27,614	$ 14,170
Total provision for income taxes:	$ 426	$ 18	$ 0	$ 0	$ 0	$ 1	$ 11	$ 3	$ 444	$ 15
Effective Income Tax Rate Reconciliation, Percent
Expected tax at 21%									21.00%	21.00%
State income tax, net of federal tax									(0.30%)	6.80%
Limited liability company loss									0	0
Non-deductible expenses									0.00%	(0.30%)
Research credits									3.40%	3.10%
Share-based compensation									1.50%	0.00%
Section 162(m) limitations									$ 2,956	$ 0
Other									(0.10%)	0.00%
Change in valuation allowance									(23.40%)	(30.60%)
Provision for income taxes									(0.40%)	0.00%

Income Taxes Net Deferred Tax Asset or Liability (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Deferred tax assets
Net operating loss	$ 45,730	$ 25,053
Compensation	892	148
Share-based compensation	1,691	0
ASC 842 lease liability	425	693
Accrued liabilities	632	1
Research credits	7,528	3,503
Total gross deferred tax assets	56,898	29,398
Valuation allowance	(56,261)	(28,647)
Net deferred tax assets	637	751
Deferred tax liabilities
Depreciable assets	(145)	(97)
ASC 842 right of use asset	(502)	(654)
In-process research and development	(2,463)	(2,463)
Other	(7)	0
Deferred tax liabilities	(3,117)	(3,214)
Net deferred tax liabilities	$ (2,480)	$ (2,463)

Income Taxes - Narrative (Details) - USD ($)	Dec. 31, 2020	Dec. 31, 2019
Operating Loss Carryforwards [Line Items]
Deferred tax assets, valuation allowance	$ 56,261,000	$ 28,647,000
Unrecognized tax benefits that would not impact effective tax rate	1,700,000
Accrued interest and penalties associated with uncertain tax positions	0	0
Domestic Tax Authority
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	183,000,000.0
Operating loss carryforwards, not subject to expiration	162,000,000.0
Deferred tax assets, tax credit carryforwards	5,200,000
Foreign Tax Authority
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	5,800,000
State and Local Jurisdiction
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards		$ 85,100,000
Deferred tax assets, tax credit carryforwards	$ 2,300,000

Income Taxes - Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Gross unrecognized tax benefits at the beginning of the year	$ 1,124	$ 741
Increase related to current year tax positions	661	383
Decrease related to prior year tax positions	197	0
Decrease related to prior year tax positions	(50)	0
Gross unrecognized tax benefits at end of the year	$ 1,932	$ 1,124

Net Loss Per Common Share/Class A Common Unit - Calculation (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019
Numerator:
Net loss attributable to Zentalis	$ (40,303)	$ (34,555)	$ (26,857)	$ (16,126)	$ (14,506)	$ (12,344)	$ (10,470)	$ (8,343)	$ (117,841)	$ (45,663)
Denominator:
Weighted average number of common shares/Class A common units outstanding, basic and diluted (in shares)	39,936	37,959	34,353	5,601					28,113	5,597
Common Stock
Denominator:
Net loss per common share/Class A common unit (USD per share)	$ (1.01)	$ (0.91)	$ (0.78)		$ (2.59)	$ (2.20)	$ (1.87)	$ (1.49)	$ (4.19)	$ 0
Class A Common Units
Denominator:
Net loss per common share/Class A common unit (USD per share)				$ (2.88)	$ 5,601,000	$ 5,599,000	$ 5,594,000	$ 5,594,000	$ 0	$ (8.16)

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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Reference 13: http://fasb.org/us-gaap/role/ref/legacyRef
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-URI http://asc.fasb.org/extlink&oid=114001798&loc=d3e33918-111571

Reference 22: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 32
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8933-108599

Reference 23: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
-Section 50
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=109234566&loc=d3e22658-107794

+ Details

Net Loss Per Common Share/Class A Common Unit - Antidilutive Securities (Details) - shares shares in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per unit (in shares)	4,538	12,621
Preferred units, as if converted to Class A common units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per unit (in shares)	0	9,950
Incentive units—Class B common units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per unit (in shares)	0	2,671
Outstanding stock options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per unit (in shares)	3,121	0
Unvested RSAs
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per unit (in shares)	742	0
Unvested RSUs
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per unit (in shares)	675	0

Related Party Disclosures (Details) - USD ($) $ / shares in Units, $ in Thousands			12 Months Ended
	Jun. 01, 2020	Dec. 21, 2017	Dec. 31, 2020	Dec. 31, 2019
Related Party Transaction [Line Items]
Number of shares acquired (in shares)			0
Capital Addition Purchase Commitments
Related Party Transaction [Line Items]
Equipment purchase and sale agreement	$ 400
Affiliated Entity \| Master Services Agreement
Related Party Transaction [Line Items]
Expenses from transactions with related party			$ 0	$ 5,000
Due to related parties			0	17,000
Affiliated Entity \| Intercompany Services Agreement
Related Party Transaction [Line Items]
Revenue from related parties			200	700
Due from related parties			$ 22,000	$ 200
VIE, Primary Beneficiary \| Kalyra Pharmaceuticals, Inc.
Related Party Transaction [Line Items]
Share price (in dollars per share)		$ 0.26
Cash payments to acquire interest		$ 4,500
Agreement term (in years)			15 years
VIE, Primary Beneficiary \| Series B Preferred Units \| Kalyra Pharmaceuticals, Inc.
Related Party Transaction [Line Items]
Number of shares acquired (in shares)		17,307,692

Selected Quarterly Financial Data (Unaudited) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019
Operating Expenses
Research and development	$ 29,521	$ 24,670	$ 17,452	$ 13,258	$ 11,869	$ 10,739	$ 8,689	$ 7,089	$ 84,901	$ 38,386
General and administrative	10,724	10,097	9,924	3,141	3,036	1,844	1,946	1,633	33,886	8,459
Total operating expenses	40,245	34,767	27,376	16,399	14,905	12,583	10,635	8,722	118,787	46,845
Operating loss	(40,245)	(34,767)	(27,376)	(16,399)	(14,905)	(12,583)	(10,635)	(8,722)	(118,787)	(46,845)
Other Income (Expense)
Investment and other income (expense), net	315	120	84	164	359	12	49	62	683	482
Net loss before income taxes	(39,930)	(34,647)	(27,292)	(16,235)	(14,546)	(12,571)	(10,586)	(8,660)	(118,104)	(46,363)
Income tax expense	426	18	0	0	0	1	11	3	444	15
Net loss	(40,356)	(34,665)	(27,292)	(16,235)	(14,546)	(12,572)	(10,597)	(8,663)	(118,548)	(46,378)
Net loss attributable to noncontrolling interests	(53)	(110)	(435)	(109)	(40)	(228)	(127)	(320)	(707)	(715)
Net loss attributable to Zentalis	$ (40,303)	$ (34,555)	$ (26,857)	$ (16,126)	$ (14,506)	$ (12,344)	$ (10,470)	$ (8,343)	$ (117,841)	$ (45,663)
Common shares/units used in computing net loss per share/Class A common unit, basic and diluted (in shares)	39,936	37,959	34,353	5,601					28,113	5,597
Common Stock
Other Income (Expense)
Net loss per share/unit outstanding, basic and diluted (USD per share)	$ (1.01)	$ (0.91)	$ (0.78)		$ (2.59)	$ (2.20)	$ (1.87)	$ (1.49)	$ (4.19)	$ 0
Class A Common Units
Other Income (Expense)
Net loss per share/unit outstanding, basic and diluted (USD per share)				$ (2.88)	$ 5,601,000	$ 5,599,000	$ 5,594,000	$ 5,594,000	$ 0	$ (8.16)

Subsequent Events (Details) $ in Thousands	1 Months Ended
Subsequent Events (Details) $ in Thousands	Mar. 31, 2021 USD ($) ft²	Dec. 31, 2020 USD ($)
Expected Operating Lease Obligation
2021		$ 1,052
2022		1,005
2023		187
Total minimum lease payments:		$ 2,244
Subsequent Event \| Office Space, 120 Month Lease Term
Subsequent Event [Line Items]
Operating leases not yet commenced, term	120 months
Operating lease not yet commenced, option to extend	five
New York \| Building \| Forecast
Expected Operating Lease Obligation
2021	$ 0
2022	1,458
2023	1,458
2024	1,459
2025	1,782
Thereafter	11,970
Total minimum lease payments:	$ 18,127
New York \| Building \| Subsequent Event \| Office Space, 120 Month Lease Term
Subsequent Event [Line Items]
Lease not yet commenced, area of leased space (in square feet) \| ft²	31,362

Label	Element	Value
Restricted Cash, Noncurrent	us-gaap_RestrictedCashNoncurrent	$ 1,320,000
Restricted Cash, Noncurrent	us-gaap_RestrictedCashNoncurrent	$ 243,000