Zentalis Pharmaceuticals (ZNTL) 10-Q 12 Nov 24 2024 Q3 Quarterly report Financial data

Cover

Cover - shares	9 Months Ended
	Sep. 30, 2024	Nov. 01, 2024
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Sep. 30, 2024
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	10275 Science Center Dr.
Entity Address, Address Line Two	Suite 200
Entity Address, City or Town	San Diego,
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	92121
City Area Code	858
Local Phone Number	263-4333
Title of 12(b) Security	Common Stock,$0.001 par value per share
Trading Symbol	ZNTL
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		71,265,400
Entity Central Index Key	0001725160
Amendment Flag	false
Document Fiscal Period Focus	Q3
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2024

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Current assets
Cash and cash equivalents	$ 41,320	$ 28,038
Marketable securities, available-for-sale	349,932	454,881
Prepaid expenses and other current assets	9,018	13,799
Total current assets	400,270	496,718
Property and equipment, net	5,016	5,819
Operating lease right-of-use assets	33,403	35,916
Prepaid expenses and other assets	5,609	6,818
Goodwill	3,736	3,736
Restricted cash	2,627	2,681
Total assets	450,661	551,688
Current liabilities
Accounts payable	8,202	14,926
Accrued expenses	46,675	54,441
Total current liabilities	54,877	69,367
Long-term lease liability	40,457	43,150
Other long-term liabilities	996	1,780
Total liabilities	96,330	114,297
Commitments and contingencies
EQUITY
Preferred stock, $0.001 par value; 10,000,000 shares authorized; no shares issued and outstanding at September 30, 2024 and December 31, 2023	0	0
Common stock, $0.001 par value; 250,000,000 shares authorized; 71,149,666 and 70,765,554 shares issued and outstanding at September 30, 2024 and December 31, 2023, respectively	71	70
Additional paid-in capital	1,359,589	1,323,576
Accumulated other comprehensive income	1,594	2,194
Accumulated deficit	(1,006,923)	(888,556)
Total stockholders’ equity	354,331	437,284
Noncontrolling interests	0	107
Total equity	354,331	437,391
Total liabilities and stockholders’ equity	$ 450,661	$ 551,688

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical) - $ / shares	Sep. 30, 2024	Dec. 31, 2023
Statement of Financial Position [Abstract]
Preferred stock, par value (in dollars per share)	$ 0.001	$ 0.001
Preferred stock, shares authorized (in shares)	10,000,000	10,000,000
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares authorized (in shares)	250,000,000	250,000,000
Common stock issued (in shares)	71,149,666	70,765,554
Common stock outstanding (in shares)	71,149,666	70,765,554

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Income Statement [Abstract]
License Revenue	$ 0	$ 0	$ 40,560	$ 0
Operating Expenses
Research and development	36,824	46,765	134,795	138,033
Zentera in-process research and development	0	0	0	45,568
General and administrative	14,608	15,953	47,110	47,986
Total operating expenses	51,432	62,718	181,905	231,587
Loss from operations	(51,432)	(62,718)	(141,345)	(231,587)
Other Income (Expense)
Investment and other income (expense), net	11,247	7,209	23,332	15,769
Net loss before income taxes	(40,185)	(55,509)	(118,013)	(215,818)
Income tax expense (benefit)	(27)	31	382	(466)
Loss on equity method investment	0	0	0	16,014
Net loss	(40,158)	(55,540)	(118,395)	(231,366)
Net loss attributable to noncontrolling interests	0	(12)	(28)	(92)
Net loss attributable to Zentalis	$ (40,158)	$ (55,528)	$ (118,367)	$ (231,274)
Net loss per common share outstanding, basic (in dollars per share)	$ (0.56)	$ (0.79)	$ (1.67)	$ (3.64)
Net loss per common share outstanding, diluted (in dollars per share)	$ (0.56)	$ (0.79)	$ (1.67)	$ (3.64)
Weighted average number of common shares outstanding, basic (in shares)	71,111	70,612	71,017	63,601
Weighted average number of common shares outstanding, diluted (in shares)	71,111	70,612	71,017	63,601

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Comprehensive Loss (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Statement of Comprehensive Income [Abstract]
Net loss	$ (40,158)	$ (55,540)	$ (118,395)	$ (231,366)
Other comprehensive income (loss):
Unrealized income (loss) on marketable securities	1,454	(21)	(600)	994
Total comprehensive loss	(38,704)	(55,561)	(118,995)	(230,372)
Comprehensive loss attributable to noncontrolling interests	0	(12)	(28)	(92)
Comprehensive loss attributable to Zentalis	$ (38,704)	$ (55,549)	$ (118,967)	$ (230,280)

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023
Operating Activities:
Consolidated net loss	$ (118,395)	$ (231,366)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	972	1,052
Operating lease right-of-use asset and fixed asset impairment	0	4,953
Noncash consideration portion of Zentera in-process research and development	0	15,045
Loss on equity method investment	0	16,014
Share-based compensation	35,906	40,942
Loss on disposal of equipment	(13)	(4)
Non-cash impact of license revenue	(25,560)	0
Non-cash recognized mark-to-market of equity securities	(7,920)	0
Accretion of discounts on marketable securities, net	(6,605)	(8,602)
Deferred income taxes	0	(853)
Deconsolidation of Kalyra	(79)	0
Changes in operating assets and liabilities:
Prepaid expenses and other assets	5,990	(5,199)
Accounts payable and accrued liabilities	(15,460)	522
Operating lease right-of-use assets and liabilities, net	6	273
Net cash used in operating activities	(131,158)	(167,223)
Investing Activities:
Purchases of marketable securities	(88,745)	(453,195)
Proceeds from maturities of marketable securities	199,700	451,207
Proceeds from sale of marketable securities	33,479	0
Proceeds from sale of property and equipment	65	0
Purchases of property and equipment	(221)	(410)
Net cash provided by (used in) investing activities	144,278	(2,398)
Financing Activities:
Proceeds from issuance of common stock, net	0	235,680
Proceeds from issuance of common stock under equity incentive plans	349	1,623
Net-settlement of restricted stock unit vesting	(241)	0
Net cash provided by financing activities	108	237,303
Net increase in cash, cash equivalents and restricted cash	13,228	67,682
Cash, cash equivalents and restricted cash at beginning of period	30,719	45,696
Cash, cash equivalents and restricted cash at end of period	43,947	113,378
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents [Abstract]
Cash and cash equivalents	41,320	110,751
Restricted cash	2,627	2,627
Total cash, cash equivalents and restricted cash reported in the Condensed Consolidated Statement of Cash Flows	$ 43,947	$ 113,378

Condensed Consolidated Statem_4

Condensed Consolidated Statements of Stockholders’ Equity - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-In Capital	Accumulated Other Comprehensive Income	Accumulated Deficit	Noncontrolling Interests
Beginning balance (in shares) at Dec. 31, 2022		59,280,000
Beginning balance at Dec. 31, 2022	$ 434,024	$ 59	$ 1,031,462	$ (1,353)	$ (596,365)	$ 221
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Share-based compensation expense	40,942		40,942
Other comprehensive (loss) income	994			994
Issuance of common stock in connection with an equity offering, net of underwriting discounts, commissions and offering costs (in shares)		11,033,000
Issuance of common stock in connection with an equity offering, net of underwriting discounts, commissions and offering costs	235,680	$ 11	235,669
Issuance of common stock in connection with restricted stock unit vesting (in shares)		235,000
Issuance of common stock upon exercise of options, net (in shares)		54,000
Issuance of common stock upon exercise of options, net	995		995
Shares issued under employee stock purchase plan (in shares)		42,000
Shares issued under employee stock purchase plan	628		628
Cancellation of restricted stock awards (in shares)		(3,000)
Net loss attributable to non-controlling interest	(92)					(92)
Net loss attributable to Zentalis	(231,274)				(231,274)
Ending balance (in shares) at Sep. 30, 2023		70,641,000
Ending balance at Sep. 30, 2023	481,897	$ 70	1,309,696	(359)	(827,639)	129
Beginning balance (in shares) at Dec. 31, 2022		59,280,000
Beginning balance at Dec. 31, 2022	$ 434,024	$ 59	1,031,462	(1,353)	(596,365)	221
Ending balance (in shares) at Dec. 31, 2023	70,765,554	70,767,000
Ending balance at Dec. 31, 2023	$ 437,391	$ 70	1,323,576	2,194	(888,556)	107
Beginning balance (in shares) at Jun. 30, 2023		70,604,000
Beginning balance at Jun. 30, 2023	523,282	$ 70	1,295,520	(338)	(772,111)	141
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Share-based compensation expense	13,867		13,867
Other comprehensive (loss) income	(21)			(21)
Issuance of common stock in connection with restricted stock unit vesting (in shares)		17,000
Issuance of common stock upon exercise of options, net (in shares)		3,000
Issuance of common stock upon exercise of options, net	54		54
Shares issued under employee stock purchase plan (in shares)		17,000
Shares issued under employee stock purchase plan	255		255
Net loss attributable to non-controlling interest	(12)					(12)
Net loss attributable to Zentalis	(55,528)				(55,528)
Ending balance (in shares) at Sep. 30, 2023		70,641,000
Ending balance at Sep. 30, 2023	$ 481,897	$ 70	1,309,696	(359)	(827,639)	129
Beginning balance (in shares) at Dec. 31, 2023	70,765,554	70,767,000
Beginning balance at Dec. 31, 2023	$ 437,391	$ 70	1,323,576	2,194	(888,556)	107
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Share-based compensation expense	35,906		35,906
Other comprehensive (loss) income	(600)			(600)
Issuance and withholding of common stock in connection with restricted stock unit vesting, net (in shares)		335,000
Issuance and withholding of common stock in connection with restricted stock unit vesting, net	$ (240)	$ 1	(241)
Issuance of common stock in connection with restricted stock unit vesting (in shares)	1,000
Deconsolidation of Kalyra	$ (79)					(79)
Issuance of common stock upon exercise of options, net (in shares)	1,000
Issuance of common stock upon exercise of options, net	$ 8		8
Shares issued under employee stock purchase plan (in shares)		48,000
Shares issued under employee stock purchase plan	340		340
Net loss attributable to non-controlling interest	(28)					(28)
Net loss attributable to Zentalis	$ (118,367)				(118,367)
Ending balance (in shares) at Sep. 30, 2024	71,149,666	71,150,000
Ending balance at Sep. 30, 2024	$ 354,331	$ 71	1,359,589	1,594	(1,006,923)	0
Beginning balance (in shares) at Jun. 30, 2024		71,107,000
Beginning balance at Jun. 30, 2024	382,581	$ 71	1,349,135	140	(966,765)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Share-based compensation expense	10,362		10,362
Other comprehensive (loss) income	1,454			1,454
Issuance of common stock in connection with restricted stock unit vesting (in shares)		13,000
Shares issued under employee stock purchase plan (in shares)		30,000
Shares issued under employee stock purchase plan	92		92
Net loss attributable to non-controlling interest	0
Net loss attributable to Zentalis	$ (40,158)				(40,158)
Ending balance (in shares) at Sep. 30, 2024	71,149,666	71,150,000
Ending balance at Sep. 30, 2024	$ 354,331	$ 71	$ 1,359,589	$ 1,594	$ (1,006,923)	$ 0

Organization and Business

Organization and Business	9 Months Ended
	Sep. 30, 2024
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization and Business	Organization and Business Organization Zentalis Pharmaceuticals, Inc. (“Zentalis,” “We” or the “Company”) is a clinical-stage biopharmaceutical company discovering and developing small molecule therapeutics targeting fundamental biological pathways of cancers. The Company’s lead product candidate, azenosertib (ZN-c3), is a potentially first-in-class and best-in-class WEE1 inhibitor for advanced solid tumors and hematologic malignancies. The Company manages its operations as a single segment for the purposes of assessing performance and making operating decisions. All of the Company’s tangible assets are held in the United States. Liquidity

Interim Unaudited Financial Sta

Interim Unaudited Financial Statements	9 Months Ended
	Sep. 30, 2024
Accounting Policies [Abstract]
Interim Unaudited Financial Statements	Interim Unaudited Financial Statements Basis of Presentation The accompanying interim unaudited condensed consolidated financial statements have been prepared in accordance with United States generally accepted accounting principles (“U.S. GAAP”) and with the rules and regulations of the U.S. Securities and Exchange Commission (“SEC”) related to a quarterly report on Form 10-Q. The year-end condensed consolidated balance sheet data was derived from the Company’s audited financial statements but do not include all disclosures required by U.S. GAAP. These interim unaudited condensed consolidated financial statements and notes thereto should be read in conjunction with the Company’s audited financial statements and notes thereto included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2023, filed with the SEC on February 27, 2024. The unaudited financial information for the interim periods presented herein reflects all adjustments which, in the opinion of management, are necessary for a fair presentation of the financial condition and results of operation for the periods presented, with such adjustments consisting only of normal recurring adjustments. Certain reclassifications have been made to the prior period condensed consolidated balance sheet to conform to the current period presentation. The accompanying interim unaudited condensed consolidated financial statements include our wholly-owned subsidiaries and Kalyra Pharmaceuticals, Inc. (“Kalyra”), a variable interest entity (“VIE”) for which we were the primary beneficiary until Kalyra was dissolved in January 2024 (See Note 4 - Business Combinations for additional information). All intercompany transactions and balances have been eliminated in consolidation. Following the dissolution of Kalyra, we no longer have an interest in any VIEs. 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. Goodwill 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”). 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 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 as of September 30, 2024 using the qualitative and quantitative assessment and determined that no impairment existed, and no charges were recorded. Significant Accounting Policies During the nine months ended September 30, 2024 we adopted the following significant accounting policies not previously reported in the Company’s significant accounting policies as described in its Annual Report on Form 10-K for the fiscal year ended December 31, 2023 . Investments in Equity Securities We carry investments in equity securities at fair value and record the changes in fair values in the Consolidated Statement of Operations as a component of Investment and other income, net. Revenue Recognition and Collaborative Arrangements The Company generates revenues from payments received under collaborative agreements and license agreements. At contract execution, we analyze our collaborative arrangements and license agreements to assess whether both parties are active participants in the activities and are exposed to significant risks and rewards and therefore are within the scope of ASC 808, Collaborative arrangements (“ASC 808”). ASC 808 does not address the recognition and measurement of payments from collaborative arrangements and instead refers companies to use other authoritative accounting literature. For collaboration arrangements within the scope of ASC 808 that contain multiple elements, we first determine which elements of the collaboration reflect a vendor-customer relationship and therefore are within the scope of ASC 606, Revenue from Contracts with Customers. When we determine elements of a collaboration agreement do not reflect a vendor-customer relationship, we consistently apply a reasonable and rational policy election we made by analogizing to authoritative accounting literature. We evaluate the income statement classification for presentation of amounts due from or owed to other participants in a collaboration arrangement based on the nature of each separate activity. To determine revenue recognition for contracts with customers, we perform the following five steps: (i) identify the contract(s) with the customer; (ii) identify the performance obligations in the contract, including whether they are distinct in the context of the contract; (iii) determine the transaction price, including the constraint on variable consideration; (iv) allocate the transaction price to the performance obligations in the contract; and (v) recognize revenue when (or as) we satisfy the performance obligations.

Significant Transactions

Significant Transactions	9 Months Ended
	Sep. 30, 2024
Equity Method Investments and Joint Ventures [Abstract]
Significant Transactions	Significant Transactions Immunome In January 2024, the Company and Immunome, Inc. (“Immunome”) entered into an exclusive, worldwide license agreement under which Immunome licensed from Zentalis ZPC-21 (now known as IM-1021), a preclinical ROR1 antibody-drug conjugate (“ADC”) and proprietary ADC technology platform (the “Immunome License Agreement”). Simultaneously, the Company and Immunome entered into a stock issuance agreement (together with the Immunome License Agreement, the “Immunome Agreements”). The upfront consideration from Immunome amounted to $40.6 million, which consisted of $15.0 million in cash and approximately 2.3 million shares (quantified using a 30-day volume average price) of Immunome common stock valued at approximately $25.6 million on the date of acquisition and presented within marketable securities, available for sale on the condensed consolidated balance sheet. Changes to the fair value of the Immunome stock are recorded as a component of investment and other income, net within the condensed consolidated statement of operations. The Company is eligible to receive up to $275.0 million in development, regulatory and sales milestones as well as tiered royalties on net sales of licensed products. The Company determined that the Immunome Agreements fall within the scope of ASC 606, Revenue from Contracts with Customers (ASC 606) as Immunome has contracted to obtain goods and services that are an output of ordinary activities and is a customer. Furthermore, subsequent to the execution of the Immunome Agreements, the Company is no longer an active participant in the research and is no longer exposed to the significant risks and rewards of the research. Management of the Company determined there was one combined performance obligation for the Immunome Agreements and know-how given the deliverables are not distinct. The Company evaluated the performance obligation within the Immunome Agreements and determined the combined performance obligation was satisfied at a point in time with Immunome as the Immunome Agreements represents a right to use the functional intellectual property as it exists at the time of the Immunome Agreements, the customer has significant risk and rewards of ownership of the asset and the customer has accepted the asset with the transfer of know-how within the quarter ended March 31, 2024. In addition, variable consideration consisting of milestone payments was evaluated based on the Company’s analysis that the possibility of achieving any of the milestone payments was remote, and therefore determined to be constrained and excluded from the transaction price. Royalties will be recognized when the underlying sales occur based on estimates and a true-up of the estimated royalty revenue to the actual royalties earned will be recorded when royalty reports are received. No License revenue related to the transaction price was recognized during the three months ended September 30, 2024 and 2023. During the nine months ended September 30, 2024 and 2023, the Company recognized $40.6 million and zero in License revenue related to the transaction price. During the nine months ended September 30, 2024 and 2023, the Company did not recognize revenue from milestone payments or royalties. See Note 12—Subsequent Events for disclosure of the Company’s sale of ZPC-21 and its proprietary ADC technology platform to Immunome that occurred in October 2024. Pfizer In April 2022, the Company and Pfizer entered into a securities purchase agreement (the “Pfizer Securities Purchase Agreement”) and the Pfizer Development Agreement relating to the Company’s product candidate, azenosertib (together with the Pfizer Securities Purchase Agreement, the “Pfizer Agreements”). As part of the Pfizer Securities Purchase Agreement, Pfizer agreed to purchase 953,834 shares of the Company’s common stock for $26.21 per share for total proceeds of $25 million. As the Company and Pfizer are both active participants in various research activities and both parties are exposed to significant risks and rewards, the Pfizer Agreements are being accounted for under ASC 808, Collaborative arrangements. The Company considered by analogy the ASC 606 criteria for combining contracts and determined that the Pfizer Agreements should be combined into a single contract because they were negotiated and executed in contemplation of one another. Furthermore, management concluded that no parts of the Pfizer Agreements are within the scope of ASC 606, Revenue from Contracts with Customers, as Pfizer was not deemed to be a customer of research and development services. The Company determined that the Pfizer Development Agreement contained two components: (i) the parties joint development activities for azenosertib and (ii) access to the information generated in the related development activities.

Business Combinations

Business Combinations	9 Months Ended
	Sep. 30, 2024
Business Combination, Asset Acquisition, and Joint Venture Formation [Abstract]
Business Combinations	Business Combinations Kalyra Pharmaceuticals, Inc. On December 21, 2017, we acquired $4.5 million of Kalyra’s Series B Preferred Stock representing a 25% equity interest in Kalyra for purposes of entering the analgesics therapeutic research space. The acquisition price was paid entirely in cash. On January 10, 2024, Kalyra was dissolved and we no longer have an ownership interest in Kalyra. The dissolution and deconsolidation of Kalyra had an immaterial impact on our consolidated financial statements. In accordance with the authoritative guidance, we concluded that, prior to its dissolution, Kalyra was a business consisting of inputs, employees, intellectual property and processes capable of producing outputs. Additionally, we concluded that Kalyra was a VIE, we were the primary beneficiary and had the power to direct the activities that most significantly affected Kalyra’s economic performance through common management and our board representation. Prior to December 21, 2017, the Company and Kalyra transacted for the delivery of research and development services and support. The financial position and results of operations of Kalyra were included in our consolidated financial statements from the date of the initial investment up until the dissolution of Kalyra on January 10, 2024. Pursuant to authoritative guidance, we recorded the identifiable assets, liabilities and noncontrolling interests in Kalyra at their fair value upon initial consolidation. The identified goodwill was comprised of the workforce and expected synergies from combining the entities . T otal assets and liabilities of Kalyra as of September 30, 2024 and December 31, 2023 are zero and immaterial, respectively. The liabilities recognized as a result of consolidating Kalyra did not represent additional claims on our general assets. Pursuant to the authoritative guidance, the equity interest in Kalyra not owned by Zentalis was reported as a noncontrolling interest on our condensed consolidated balance sheets. The following is a reconciliation of equity (net assets) attributable to the noncontrolling interest (in thousands): September 30, December 31, 2024 2023 Noncontrolling interest at beginning of period $ 107 $ 221 Net loss attributable to noncontrolling interest (28) (114) Deconsolidation of Kalyra (79) — Noncontrolling interest at end of period $ — $ 107

Fair Value Measurement

Fair Value Measurement	9 Months Ended
	Sep. 30, 2024
Fair Value Disclosures [Abstract]
Fair Value Measurement	Fair Value Measurement Available-for-sale marketable debt securities consisted of the following (in thousands): September 30, 2024 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value Commercial paper $ 8,481 $ 1 $ — $ 8,482 Corporate debt securities 252,649 1,486 (18) 254,117 US government agencies 7,975 11 — 7,986 US treasury securities 79,233 142 (28) 79,347 $ 348,338 $ 1,640 $ (46) $ 349,932 December 31, 2023 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value Commercial paper $ 75,227 $ 60 $ (15) $ 75,272 Corporate debt securities 229,896 2,036 — 231,932 US government agencies 83,025 100 (78) 83,047 US treasury securities 64,538 103 (11) 64,630 $ 452,686 $ 2,299 $ (104) $ 454,881 As of September 30, 2024, four of our available-for-sale debt securities with a fair market value of $39.5 million were in a gross unrealized loss position of $46 thousand. Four have been in a gross unrealized loss position of $46 thousand for less than one year and none have been in a gross unrealized loss position for more than one year. 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 September 30, 2024, 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): September 30, 2024 December 31, 2023 Estimated Fair Value Due within one year $ 260,779 $ 267,336 After one but within five years 89,153 187,545 $ 349,932 $ 454,881 The Company had $0.5 million in contingent consideration liabilities as of September 30, 2024 related to the agreement to terminate its Collaboration and License Agreements with Zentera. The contingent consideration balance is limited to one potential milestone payment measured at fair value. The fair value of the contingent consideration is estimated based on the monetary value of the milestone discounted for the probability of achieving the milestone and a present value factor based on the timing of when the milestone is expected to be achieved. The value for the contingent consideration balance is based on significant inputs not observable in the market which represents Level 3 measurement within the fair value hierarchy. The following table summarizes the financial assets and liabilities that are measured on a recurring basis at fair value as of September 30, 2024 and December 31, 2023 (in thousands): September 30, 2024 Level 1 Level 2 Level 3 Total estimated fair value Financial assets: Cash equivalents: Money market funds $ 10,171 $ — $ — $ 10,171 Total cash equivalents: 10,171 — — 10,171 Available-for-sale marketable securities: Commercial paper — 8,482 — 8,482 Corporate debt securities — 254,117 — 254,117 US government agencies — 7,986 — 7,986 US treasury securities — 79,347 — 79,347 Total available-for-sale marketable securities: — 349,932 — 349,932 Total assets measured at fair value $ 10,171 $ 349,932 $ — $ 360,103 Financial liabilities: Contingent consideration — — 500 500 Total financial liabilities $ — $ — $ 500 $ 500 December 31, 2023 Level 1 Level 2 Level 3 Total estimated fair value Financial assets: Cash equivalents: Money market funds $ 4,755 $ — $ — $ 4,755 Total cash equivalents: 4,755 — — 4,755 Available-for-sale marketable securities: Commercial paper — 75,272 — 75,272 Corporate debt securities — 231,932 — 231,932 US government agencies — 83,047 — 83,047 US treasury securities — 64,630 — 64,630 Total available-for-sale marketable securities: — 454,881 — 454,881 Total assets measured at fair value $ 4,755 $ 454,881 $ — $ 459,636 Financial liabilities: Contingent consideration — — 500 500 Total financial liabilities $ — $ — $ 500 $ 500 During the three months ended September 30, 2024, we divested 2,298,586 shares of Immunome. Our proceeds from the sale of the equity securities were approximately $33.5 million in the three and nine months ended September 30, 2024. We recorded equity investment gains of $5.7 million and $7.9 million during the three and nine months September 30, 2024. The following significant unobservable inputs were used in the valuation of the contingent consideration payable to Zentera pursuant to the Termination Agreement at September 30, 2024: Contingent Consideration Liability Fair Value as of September 30, 2024 Valuation Technique Unobservable Input Range (in thousands) Milestone payment $ 500 Discounted cash flow Likelihood of occurrence 1.0% - 2.4% Discount rate 40% Expected term Perpetuity The following table reflects the activity for the Company’s contingent consideration, measured at fair value using Level 3 inputs (in thousands): Contingent consideration at December 31, 2023 500 Changes in the fair value of contingent consideration — Contingent consideration at September 30, 2024 $ 500

Prepaid Expenses and Other Asse

Prepaid Expenses and Other Assets	9 Months Ended
	Sep. 30, 2024
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Prepaid Expenses and Other Assets	Prepaid Expenses and Other Assets Prepaid expenses and other assets consisted of the following (in thousands): September 30, December 31, 2024 2023 Prepaid insurance $ 513 $ 747 Prepaid software licenses and maintenance 430 691 Foreign R&D credit refund 403 500 Prepaid research and development expenses 8,121 13,640 Interest receivable 3,305 3,337 Sublease assets 659 1,471 Other prepaid expenses 1,196 231 Total prepaid expenses and other assets 14,627 20,617 Less long-term portion 5,609 6,818 Total prepaid expenses and other assets, current $ 9,018 $ 13,799

Property and Equipment, net

Property and Equipment, net	9 Months Ended
	Sep. 30, 2024
Property, Plant and Equipment [Abstract]
Property and Equipment, net	Property and Equipment, net Property and equipment, net consisted of the following (in thousands): September 30, December 31, 2024 2023 Lab equipment $ 3,382 $ 3,069 Leasehold improvements 4,168 4,235 Office equipment and furniture 1,280 1,340 Computer equipment 143 150 Construction in progress — 173 Subtotal 8,973 8,967 Accumulated depreciation and amortization (3,957) (3,148) Property and equipment, net $ 5,016 $ 5,819 Depreciation and amortization expense for the three months ended September 30, 2024 and 2023 was approximately $321 thousand and $348 thousand, respectively. Depreciation and amortization expense for the nine months ended September 30, 2024 and 2023 was $972 thousand and $1.1 million, respectively.

Accrued Expenses

Accrued Expenses	9 Months Ended
	Sep. 30, 2024
Payables and Accruals [Abstract]
Accrued Expenses	Accrued Expenses Accrued expenses consist of the following (in thousands): September 30, December 31, 2024 2023 Accrued research and development expenses $ 32,743 $ 36,261 Accrued employee expenses 10,826 14,477 Accrued general and administrative expenses 422 1,032 Lease liability 2,809 2,623 Contingent consideration 500 500 Income Taxes payable 152 281 Accrued legal expenses 219 1,047 Total accrued expenses 47,671 56,221 Less long-term portion 996 1,780 Total accrued expenses $ 46,675 $ 54,441

Stockholders_ Equity

Stockholders’ Equity	9 Months Ended
	Sep. 30, 2024
Equity [Abstract]
Stockholders’ Equity	Stockholders’ Equity Follow-on Offering of Common Stock On June 15, 2023, we completed a follow-on offering in which we issued and sold 11,032,656 shares of common stock at a public offering price of $22.66 per share. The total gross proceeds for the offering were approximately $250.0 million, before deducting offering expenses of $14.3 million payable by us. Share-based Compensation Effective April 2020, the Company’s Board of Directors adopted, and the Company’s stockholders approved, the 2020 Incentive Award Plan (the “2020 Plan”), which allows for grants to selected employees, consultants and non-employee members of the Board of Directors. We currently grant stock options and restricted stock units (“RSUs”), under the 2020 Plan. Awards may be made under the 2020 Plan covering up to 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. At September 30, 2024, 10,462,700 shares were subject to outstanding awards under the 2020 Plan and 3,816,197 shares were available for future grants of share-based awards under the 2020 Plan. In July 2022, the Company’s Board of Directors approved the Zentalis Pharmaceuticals, Inc. 2022 Employment Inducement Incentive Award Plan (the “2022 Inducement Plan”), which is used exclusively for the grant of equity awards to new employees as an inducement material to the employees’ entering into employment with the Company. The Board of Directors has reserved 3,275,000 shares of the Company’s common stock for issuance pursuant to awards granted under the 2022 Inducement Plan. At September 30, 2024, 2,704,400 shares were subject to outstanding awards under the 2022 Inducement Plan and 545,600 shares were available for future grants of share-based awards under the 2022 Inducement Plan. Total share-based compensation expense related to share based awards was comprised of the following (in thousands): Three Months Ended Nine Months Ended 2024 2023 2024 2023 Research and development expense $ 3,083 $ 5,854 $ 11,979 $ 17,712 General and administrative expense 7,279 8,013 23,927 23,230 Total share-based compensation expense $ 10,362 $ 13,867 $ 35,906 $ 40,942 Share-based compensation expense by type of share-based award (in thousands): Three Months Ended Nine Months Ended 2024 2023 2024 2023 Stock Options $ 8,357 $ 10,408 $ 27,784 $ 31,222 Employee Stock Purchase Plan 139 87 330 303 RSAs and RSUs 1,866 3,372 7,792 9,417 $ 10,362 $ 13,867 $ 35,906 $ 40,942 Stock Options and Restricted Stock Units The exercise price of stock options granted is equal to the closing price of the Company’s 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 nine months ended September 30, 2024 and September 30, 2023 was determined with the following assumptions: September 30, 2024 September 30, 2023 Expected volatility 75.3% - 78.4% 77.5% - 80.8% Average expected term (in years) 5.9 - 6.1 5.5 - 6.1 Risk-free interest rate 3.7% - 4.6% 3.4% - 4.2% Expected dividend yield — % — % Employee Stock Purchase Plan Effective April 2020, the Company’s Board of Directors adopted, and the Company’s stockholders approved the Zentalis Pharmaceuticals, Inc. 2020 Employee Stock Purchase Plan (the “ESPP”), which was subsequently amended and restated effective March 15, 2021. The maximum aggregate number of shares of the Company’s common stock available for issuance under the ESPP at September 30, 2024 was 1,865,179. Under the terms of the ESPP, the Company’s employees may elect to have up to 20% of their compensation, up to a maximum value of $25,000 per calendar year, withheld to purchase shares of the Company’s common stock for a purchase price equal to 85% of the lower of the fair market value per share (at closing) of the Company’s common stock on (i) the first trading day of a six-month offering period, or (ii) the applicable purchase date, defined as the last trading day of the six-month offering period. The weighted average assumptions used to estimate the fair value of stock purchase rights under the ESPP during the period ended are as follows: Ended September 30, 2024 ESPP Volatility 107.3 % Expected term (years) 0.5 Risk free rate 5.4 % Expected dividend yield — Compensation Expense Summary 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): September 30, 2024 Unrecognized Remaining Stock options $ 68,108 2.41 RSUs 21,453 2.77

Commitments and Contingencies

Commitments and Contingencies	9 Months Ended
	Sep. 30, 2024
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	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 settlement. 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 that require a loss liability to be recorded. Lease Termination In December 2023, we entered into a lease for approximately 4,115 square feet of office space in New York, New York. The lease commenced in December 2023 and had a lease term through August 2027. In June 2024, we entered into an agreement to terminate this lease in exchange for consideration of $0.5 million. Leases Our commitments include payments related to operating leases. Approximate annual future minimum operating lease payments as of September 30, 2024 are as follows (in thousands): Year Operating Leases 2024 (remaining) $ 1,584 2025 6,799 2026 7,278 2027 7,451 2028 7,760 Thereafter 31,019 Total minimum lease payments: 61,891 Less: imputed interest (18,625) Total operating lease liabilities 43,266 Less: current portion (2,809) Lease liability, net of current portion $ 40,457 The weighted-average remaining lease term of our operating leases is approximately 8.0 years.

Net Income (Loss) Per Common Sh

Net Income (Loss) Per Common Share	9 Months Ended
	Sep. 30, 2024
Earnings Per Share [Abstract]
Net Income (Loss) Per Common Share	Net Income (Loss) Per Common Share Basic and diluted net income (loss) per common share were calculated as follows (in thousands except per share amounts): Three Months Ended Nine Months Ended 2024 2023 2024 2023 Numerator: Net income (loss) attributable to Zentalis $ (40,158) $ (55,528) $ (118,367) $ (231,274) Denominator: Weighted average number of common shares outstanding, basic and diluted 71,111 70,612 71,017 63,601 Net loss per common share $ (0.56) $ (0.79) $ (1.67) $ (3.64) Our potential and dilutive securities, which include outstanding stock options, unvested RSAs and unvested RSUs have been excluded from the computation of diluted net loss per common share as the effect would be anti-dilutive. The following common stock equivalents have been excluded from the calculations of diluted net income (loss) per common share because their inclusion would be antidilutive (in thousands). September 30, 2024 2023 Outstanding stock options 11,214 10,260 Unvested RSAs — 4 Unvested RSUs 1,953 1,476 13,167 11,740

Subsequent Events

Subsequent Events	9 Months Ended
	Sep. 30, 2024
Subsequent Events [Abstract]
Subsequent Events	Subsequent Events Immunome Asset Sale

Pay vs Performance Disclosure

Pay vs Performance Disclosure - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Pay vs Performance Disclosure
Net loss attributable to Zentalis	$ (40,158)	$ (55,528)	$ (118,367)	$ (231,274)

Insider Trading Arrangements

Insider Trading Arrangements	3 Months Ended
	Sep. 30, 2024
Trading Arrangements, by Individual
Rule 10b5-1 Arrangement Adopted	false
Non-Rule 10b5-1 Arrangement Adopted	false
Rule 10b5-1 Arrangement Terminated	false
Non-Rule 10b5-1 Arrangement Terminated	false

Interim Unaudited Financial S_2

Interim Unaudited Financial Statements (Policies)	9 Months Ended
	Sep. 30, 2024
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The accompanying interim unaudited condensed consolidated financial statements have been prepared in accordance with United States generally accepted accounting principles (“U.S. GAAP”) and with the rules and regulations of the U.S. Securities and Exchange Commission (“SEC”) related to a quarterly report on Form 10-Q. The year-end condensed consolidated balance sheet data was derived from the Company’s audited financial statements but do not include all disclosures required by U.S. GAAP. These interim unaudited condensed consolidated financial statements and notes thereto should be read in conjunction with the Company’s audited financial statements and notes thereto included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2023, filed with the SEC on February 27, 2024. The unaudited financial information for the interim periods presented herein reflects all adjustments which, in the opinion of management, are necessary for a fair presentation of the financial condition and results of operation for the periods presented, with such adjustments consisting only of normal recurring adjustments. Certain reclassifications have been made to the prior period condensed consolidated balance sheet to conform to the current period presentation.
Consolidation	The accompanying interim unaudited condensed consolidated financial statements include our wholly-owned subsidiaries and Kalyra Pharmaceuticals, Inc. (“Kalyra”), a variable interest entity (“VIE”) for which we were the primary beneficiary until Kalyra was dissolved in January 2024 (See Note 4 - Business Combinations for additional information). All intercompany transactions and balances have been eliminated in consolidation. Following the dissolution of Kalyra, we no longer have an interest in any VIEs.
Use of Estimates	Use of Estimates The preparation of consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the 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.
Goodwill	Goodwill 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”).
Investments in Equity Securities	Investments in Equity Securities We carry investments in equity securities at fair value and record the changes in fair values in the Consolidated Statement of Operations as a component of Investment and other income, net.
Revenue Recognition and Collaborative Arrangements	Revenue Recognition and Collaborative Arrangements The Company generates revenues from payments received under collaborative agreements and license agreements. At contract execution, we analyze our collaborative arrangements and license agreements to assess whether both parties are active participants in the activities and are exposed to significant risks and rewards and therefore are within the scope of ASC 808, Collaborative arrangements (“ASC 808”). ASC 808 does not address the recognition and measurement of payments from collaborative arrangements and instead refers companies to use other authoritative accounting literature. For collaboration arrangements within the scope of ASC 808 that contain multiple elements, we first determine which elements of the collaboration reflect a vendor-customer relationship and therefore are within the scope of ASC 606, Revenue from Contracts with Customers. When we determine elements of a collaboration agreement do not reflect a vendor-customer relationship, we consistently apply a reasonable and rational policy election we made by analogizing to authoritative accounting literature. We evaluate the income statement classification for presentation of amounts due from or owed to other participants in a collaboration arrangement based on the nature of each separate activity. To determine revenue recognition for contracts with customers, we perform the following five steps: (i) identify the contract(s) with the customer; (ii) identify the performance obligations in the contract, including whether they are distinct in the context of the contract; (iii) determine the transaction price, including the constraint on variable consideration; (iv) allocate the transaction price to the performance obligations in the contract; and (v) recognize revenue when (or as) we satisfy the performance obligations.

Business Combinations (Tables)

Business Combinations (Tables)	9 Months Ended
	Sep. 30, 2024
Business Combination, Asset Acquisition, and Joint Venture Formation [Abstract]
Schedule of Reconciliation of Equity Attributable to Noncontrolling Interest	The following is a reconciliation of equity (net assets) attributable to the noncontrolling interest (in thousands): September 30, December 31, 2024 2023 Noncontrolling interest at beginning of period $ 107 $ 221 Net loss attributable to noncontrolling interest (28) (114) Deconsolidation of Kalyra (79) — Noncontrolling interest at end of period $ — $ 107

Fair Value Measurement (Tables)

Fair Value Measurement (Tables)	9 Months Ended
	Sep. 30, 2024
Fair Value Disclosures [Abstract]
Schedule of Components of Available-for-sale Marketable Securities	Available-for-sale marketable debt securities consisted of the following (in thousands): September 30, 2024 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value Commercial paper $ 8,481 $ 1 $ — $ 8,482 Corporate debt securities 252,649 1,486 (18) 254,117 US government agencies 7,975 11 — 7,986 US treasury securities 79,233 142 (28) 79,347 $ 348,338 $ 1,640 $ (46) $ 349,932 December 31, 2023 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value Commercial paper $ 75,227 $ 60 $ (15) $ 75,272 Corporate debt securities 229,896 2,036 — 231,932 US government agencies 83,025 100 (78) 83,047 US treasury securities 64,538 103 (11) 64,630 $ 452,686 $ 2,299 $ (104) $ 454,881
Schedule of Contractual Maturities of Available-for-sale Debt Securities	Contractual maturities of available-for-sale debt securities are as follows (in thousands): September 30, 2024 December 31, 2023 Estimated Fair Value Due within one year $ 260,779 $ 267,336 After one but within five years 89,153 187,545 $ 349,932 $ 454,881
Schedule of Fair Value of Assets and Liabilities Measured on a Recurring Basis	The following table summarizes the financial assets and liabilities that are measured on a recurring basis at fair value as of September 30, 2024 and December 31, 2023 (in thousands): September 30, 2024 Level 1 Level 2 Level 3 Total estimated fair value Financial assets: Cash equivalents: Money market funds $ 10,171 $ — $ — $ 10,171 Total cash equivalents: 10,171 — — 10,171 Available-for-sale marketable securities: Commercial paper — 8,482 — 8,482 Corporate debt securities — 254,117 — 254,117 US government agencies — 7,986 — 7,986 US treasury securities — 79,347 — 79,347 Total available-for-sale marketable securities: — 349,932 — 349,932 Total assets measured at fair value $ 10,171 $ 349,932 $ — $ 360,103 Financial liabilities: Contingent consideration — — 500 500 Total financial liabilities $ — $ — $ 500 $ 500 December 31, 2023 Level 1 Level 2 Level 3 Total estimated fair value Financial assets: Cash equivalents: Money market funds $ 4,755 $ — $ — $ 4,755 Total cash equivalents: 4,755 — — 4,755 Available-for-sale marketable securities: Commercial paper — 75,272 — 75,272 Corporate debt securities — 231,932 — 231,932 US government agencies — 83,047 — 83,047 US treasury securities — 64,630 — 64,630 Total available-for-sale marketable securities: — 454,881 — 454,881 Total assets measured at fair value $ 4,755 $ 454,881 $ — $ 459,636 Financial liabilities: Contingent consideration — — 500 500 Total financial liabilities $ — $ — $ 500 $ 500
Schedule of Measurement Inputs for Contingent Consideration Liability	The following significant unobservable inputs were used in the valuation of the contingent consideration payable to Zentera pursuant to the Termination Agreement at September 30, 2024: Contingent Consideration Liability Fair Value as of September 30, 2024 Valuation Technique Unobservable Input Range (in thousands) Milestone payment $ 500 Discounted cash flow Likelihood of occurrence 1.0% - 2.4% Discount rate 40% Expected term Perpetuity
Schedule of Activity for Contingent Consideration	The following table reflects the activity for the Company’s contingent consideration, measured at fair value using Level 3 inputs (in thousands): Contingent consideration at December 31, 2023 500 Changes in the fair value of contingent consideration — Contingent consideration at September 30, 2024 $ 500

Prepaid Expenses and Other As_2

Prepaid Expenses and Other Assets (Tables)	9 Months Ended
	Sep. 30, 2024
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): September 30, December 31, 2024 2023 Prepaid insurance $ 513 $ 747 Prepaid software licenses and maintenance 430 691 Foreign R&D credit refund 403 500 Prepaid research and development expenses 8,121 13,640 Interest receivable 3,305 3,337 Sublease assets 659 1,471 Other prepaid expenses 1,196 231 Total prepaid expenses and other assets 14,627 20,617 Less long-term portion 5,609 6,818 Total prepaid expenses and other assets, current $ 9,018 $ 13,799

Property and Equipment, net (Ta

Property and Equipment, net (Tables)	9 Months Ended
	Sep. 30, 2024
Property, Plant and Equipment [Abstract]
Summary of Property and Equipment, net	Property and equipment, net consisted of the following (in thousands): September 30, December 31, 2024 2023 Lab equipment $ 3,382 $ 3,069 Leasehold improvements 4,168 4,235 Office equipment and furniture 1,280 1,340 Computer equipment 143 150 Construction in progress — 173 Subtotal 8,973 8,967 Accumulated depreciation and amortization (3,957) (3,148) Property and equipment, net $ 5,016 $ 5,819

Accrued Expenses (Tables)

Accrued Expenses (Tables)	9 Months Ended
	Sep. 30, 2024
Payables and Accruals [Abstract]
Schedule of Accrued Expenses	Accrued expenses consist of the following (in thousands): September 30, December 31, 2024 2023 Accrued research and development expenses $ 32,743 $ 36,261 Accrued employee expenses 10,826 14,477 Accrued general and administrative expenses 422 1,032 Lease liability 2,809 2,623 Contingent consideration 500 500 Income Taxes payable 152 281 Accrued legal expenses 219 1,047 Total accrued expenses 47,671 56,221 Less long-term portion 996 1,780 Total accrued expenses $ 46,675 $ 54,441

Stockholders_ Equity (Tables)

Stockholders’ Equity (Tables)	9 Months Ended
	Sep. 30, 2024
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): Three Months Ended Nine Months Ended 2024 2023 2024 2023 Research and development expense $ 3,083 $ 5,854 $ 11,979 $ 17,712 General and administrative expense 7,279 8,013 23,927 23,230 Total share-based compensation expense $ 10,362 $ 13,867 $ 35,906 $ 40,942 Share-based compensation expense by type of share-based award (in thousands): Three Months Ended Nine Months Ended 2024 2023 2024 2023 Stock Options $ 8,357 $ 10,408 $ 27,784 $ 31,222 Employee Stock Purchase Plan 139 87 330 303 RSAs and RSUs 1,866 3,372 7,792 9,417 $ 10,362 $ 13,867 $ 35,906 $ 40,942
Schedule of Fair Value Assumptions for Stock Options	The fair value of the stock options granted during the nine months ended September 30, 2024 and September 30, 2023 was determined with the following assumptions: September 30, 2024 September 30, 2023 Expected volatility 75.3% - 78.4% 77.5% - 80.8% Average expected term (in years) 5.9 - 6.1 5.5 - 6.1 Risk-free interest rate 3.7% - 4.6% 3.4% - 4.2% Expected dividend yield — % — %
Schedule of Fair Value Assumptions for ESPP	The weighted average assumptions used to estimate the fair value of stock purchase rights under the ESPP during the period ended are as follows: Ended September 30, 2024 ESPP Volatility 107.3 % Expected term (years) 0.5 Risk free rate 5.4 % Expected dividend yield —
Schedule of Unrecognized Compensation Cost	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): September 30, 2024 Unrecognized Remaining Stock options $ 68,108 2.41 RSUs 21,453 2.77

Commitments and Contingencies (

Commitments and Contingencies (Tables)	9 Months Ended
	Sep. 30, 2024
Commitments and Contingencies Disclosure [Abstract]
Schedule of Future Minimum Operating Lease Payments	Approximate annual future minimum operating lease payments as of September 30, 2024 are as follows (in thousands): Year Operating Leases 2024 (remaining) $ 1,584 2025 6,799 2026 7,278 2027 7,451 2028 7,760 Thereafter 31,019 Total minimum lease payments: 61,891 Less: imputed interest (18,625) Total operating lease liabilities 43,266 Less: current portion (2,809) Lease liability, net of current portion $ 40,457

Net Income (Loss) Per Common _2

Net Income (Loss) Per Common Share (Tables)	9 Months Ended
	Sep. 30, 2024
Earnings Per Share [Abstract]
Schedule of Basic and Diluted Net Income (Loss) Per Unit	Basic and diluted net income (loss) per common share were calculated as follows (in thousands except per share amounts): Three Months Ended Nine Months Ended 2024 2023 2024 2023 Numerator: Net income (loss) attributable to Zentalis $ (40,158) $ (55,528) $ (118,367) $ (231,274) Denominator: Weighted average number of common shares outstanding, basic and diluted 71,111 70,612 71,017 63,601 Net loss per common share $ (0.56) $ (0.79) $ (1.67) $ (3.64)
Schedule of Antidilutive Securities Excluded from Computation of Diluted Net Income (Loss) Per Common Share	The following common stock equivalents have been excluded from the calculations of diluted net income (loss) per common share because their inclusion would be antidilutive (in thousands). September 30, 2024 2023 Outstanding stock options 11,214 10,260 Unvested RSAs — 4 Unvested RSUs 1,953 1,476 13,167 11,740

Significant Transactions (Detai

Significant Transactions (Details) - USD ($)	1 Months Ended		3 Months Ended		9 Months Ended
	Jan. 31, 2024	Apr. 30, 2022	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023
Schedule of Equity Method Investments [Line Items]
License revenue			$ 0	$ 0	$ 40,560,000	$ 0
Total proceeds					0	235,680,000
Common stock, value, issued			71,000		71,000		$ 70,000
Immunome, Inc
Schedule of Equity Method Investments [Line Items]
License revenue	$ 40,600,000		0	0	40,600,000	0
Upfront consideration, cash	$ 15,000,000
Upfront consideration, shares purchased (in shares)	2,300,000
Trailing volume-weighted average price period (in days)	30 days
Value of common stock	$ 25,600,000
Receivable	$ 275,000,000
Revenue from milestone payments or royalties					0	0
Pfizer | Pfizer Agreements
Schedule of Equity Method Investments [Line Items]
Share price (in dollars per share)		$ 26.21
Total proceeds		$ 25,000,000
Common stock, value, issued		20,800,000
Common stock, value, issued, premium (discount)		$ 4,200,000
Decrease in research and development expense			$ 100,000	$ 500,000	$ 900,000	$ 700,000
Pfizer | Pfizer Agreements | Common Stock
Schedule of Equity Method Investments [Line Items]
Number of shares issued and sold (in shares)		953,834

Business Combinations - Narrati

Business Combinations - Narrative (Details) - USD ($)	Dec. 21, 2017	Sep. 30, 2024	Dec. 31, 2023
Variable Interest Entity [Line Items]
Assets		$ 450,661,000	$ 551,688,000
Liabilities		96,330,000	114,297,000
Kalyra Pharmaceuticals, Inc.
Variable Interest Entity [Line Items]
Cash payments to acquire interest	$ 4,500,000
Ownership percentage	25%
Kalyra Pharmaceuticals, Inc. | Variable Interest Entity, Not Primary Beneficiary
Variable Interest Entity [Line Items]
Assets		0	0
Liabilities		$ 0	$ 0

Business Combinations - Reconci

Business Combinations - Reconciliation of Equity (Net Assets) Attributable to Noncontrolling Interest (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Noncontrolling interest at beginning of period			$ 107
Net loss attributable to noncontrolling interest	$ 0	$ (12)	(28)	$ (92)
Deconsolidation of Kalyra			(79)
Noncontrolling interest at end of period	0		0		$ 107
VIE, Primary Beneficiary
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Noncontrolling interest at beginning of period			107	$ 221	221
Net loss attributable to noncontrolling interest			(28)		(114)
Deconsolidation of Kalyra			(79)		0
Noncontrolling interest at end of period	$ 0		$ 0		$ 107

Fair Value Measurement - Compon

Fair Value Measurement - Components of Available-for-sale Marketable Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 348,338	$ 452,686
Gross Unrealized Gains	1,640	2,299
Gross Unrealized Losses	(46)	(104)
Estimated Fair Value	349,932	454,881
Commercial paper
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	8,481	75,227
Gross Unrealized Gains	1	60
Gross Unrealized Losses	0	(15)
Estimated Fair Value	8,482	75,272
Corporate debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	252,649	229,896
Gross Unrealized Gains	1,486	2,036
Gross Unrealized Losses	(18)	0
Estimated Fair Value	254,117	231,932
US government agencies
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	7,975	83,025
Gross Unrealized Gains	11	100
Gross Unrealized Losses	0	(78)
Estimated Fair Value	7,986	83,047
US treasury securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	79,233	64,538
Gross Unrealized Gains	142	103
Gross Unrealized Losses	(28)	(11)
Estimated Fair Value	$ 79,347	$ 64,630

Fair Value Measurement - Narrat

Fair Value Measurement - Narrative (Details)	3 Months Ended	9 Months Ended
	Sep. 30, 2024 USD ($) security potential_milestone_payment shares	Sep. 30, 2024 USD ($) security potential_milestone_payment	Sep. 30, 2023 USD ($)	Dec. 31, 2023 USD ($)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Number of available-for-sale securities in unrealized loss position | security	4	4
Debt securities fair market value	$ 39,500,000	$ 39,500,000
Fair market value of available-for-sale securities in unrealized loss position	$ 46,000	$ 46,000
Number of available-for-sale securities in unrealized loss position for less than one year | security	4	4
Gross unrealized loss position for less than one year	$ 46,000	$ 46,000
Number of available-for-sale securities in unrealized loss position for more than one year | security	0	0
Gross unrealized loss position for more than one year (less than)	$ 0	$ 0
Contingent consideration	500,000	500,000		$ 500,000
Equity investment gains		7,920,000	$ 0
Zentera | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Contingent consideration	$ 500,000	$ 500,000
Number of potential milestone payments | potential_milestone_payment	1	1
Immunome, Inc
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Divested shares (in shares) | shares	2,298,586
Proceeds from the sale of the equity securities	$ 33,500,000	$ 33,500,000
Equity investment gains	$ 5,700,000	$ 7,900,000

Fair Value Measurement - Contra

Fair Value Measurement - Contractual Maturities of Available-for-sale Debt Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Fair Value Disclosures [Abstract]
Due within one year	$ 260,779	$ 267,336
After one but within five years	89,153	187,545
Total	$ 349,932	$ 454,881

Fair Value Measurement - Fair V

Fair Value Measurement - Fair Value of Assets and Liabilities Measured on a Recurring Basis (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Financial assets:
Cash equivalents	$ 10,171	$ 4,755
Marketable securities, available-for-sale	349,932	454,881
Total available-for-sale marketable securities:	349,932	454,881
Total assets measured at fair value	360,103	459,636
Financial liabilities:
Contingent consideration	500	500
Total financial liabilities	500	500
Level 1
Financial assets:
Cash equivalents	10,171	4,755
Total available-for-sale marketable securities:	0	0
Total assets measured at fair value	10,171	4,755
Financial liabilities:
Contingent consideration	0	0
Total financial liabilities	0	0
Level 2
Financial assets:
Cash equivalents	0	0
Total available-for-sale marketable securities:	349,932	454,881
Total assets measured at fair value	349,932	454,881
Financial liabilities:
Contingent consideration	0	0
Total financial liabilities	0	0
Level 3
Financial assets:
Cash equivalents	0	0
Total available-for-sale marketable securities:	0	0
Total assets measured at fair value	0	0
Financial liabilities:
Contingent consideration	500	500
Total financial liabilities	500	500
Commercial paper
Financial assets:
Marketable securities, available-for-sale	8,482	75,272
Commercial paper | Level 1
Financial assets:
Marketable securities, available-for-sale	0	0
Commercial paper | Level 2
Financial assets:
Marketable securities, available-for-sale	8,482	75,272
Commercial paper | Level 3
Financial assets:
Marketable securities, available-for-sale	0	0
Corporate debt securities
Financial assets:
Marketable securities, available-for-sale	254,117	231,932
Corporate debt securities | Level 1
Financial assets:
Marketable securities, available-for-sale	0	0
Corporate debt securities | Level 2
Financial assets:
Marketable securities, available-for-sale	254,117	231,932
Corporate debt securities | Level 3
Financial assets:
Marketable securities, available-for-sale	0	0
US government agencies
Financial assets:
Marketable securities, available-for-sale	7,986	83,047
US government agencies | Level 1
Financial assets:
Marketable securities, available-for-sale	0	0
US government agencies | Level 2
Financial assets:
Marketable securities, available-for-sale	7,986	83,047
US government agencies | Level 3
Financial assets:
Marketable securities, available-for-sale	0	0
US treasury securities
Financial assets:
Marketable securities, available-for-sale	79,347	64,630
US treasury securities | Level 1
Financial assets:
Marketable securities, available-for-sale	0	0
US treasury securities | Level 2
Financial assets:
Marketable securities, available-for-sale	79,347	64,630
US treasury securities | Level 3
Financial assets:
Marketable securities, available-for-sale	0	0
Money market funds
Financial assets:
Cash equivalents	10,171	4,755
Money market funds | Level 1
Financial assets:
Cash equivalents	10,171	4,755
Money market funds | Level 2
Financial assets:
Cash equivalents	0	0
Money market funds | Level 3
Financial assets:
Cash equivalents	$ 0	$ 0

Fair Value Measurement - Measur

Fair Value Measurement - Measurement Inputs for Contingent Consideration Liability (Details) $ in Thousands	Sep. 30, 2024 USD ($)	Dec. 31, 2023 USD ($)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Contingent consideration	$ 500	$ 500
Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Contingent consideration	$ 500	$ 500
Level 3 | Discounted cash flow | Likelihood of occurrence | Minimum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input	0.010
Level 3 | Discounted cash flow | Likelihood of occurrence | Maximum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input	0.024
Level 3 | Milestone payment | Discount rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input	0.40
Level 3 | Milestone payment | Discounted cash flow
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Contingent consideration	$ 500

Fair Value Measurement - Activi

Fair Value Measurement - Activity for Contingent Consideration (Details) - Contingent Consideration Liability $ in Thousands	9 Months Ended
	Sep. 30, 2024 USD ($)
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Contingent consideration, beginning balance	$ 500
Changes in the fair value of contingent consideration	0
Contingent consideration, ending balance	$ 500

Prepaid Expenses and Other As_3

Prepaid Expenses and Other Assets (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Prepaid insurance	$ 513	$ 747
Prepaid software licenses and maintenance	430	691
Foreign R&D credit refund	403	500
Prepaid research and development expenses	8,121	13,640
Interest receivable	3,305	3,337
Sublease assets	659	1,471
Other prepaid expenses	1,196	231
Total prepaid expenses and other assets	14,627	20,617
Less long-term portion	5,609	6,818
Total prepaid expenses and other assets, current	$ 9,018	$ 13,799

Property and Equipment, net - S

Property and Equipment, net - Summary (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Property, Plant and Equipment [Line Items]
Subtotal	$ 8,973	$ 8,967
Accumulated depreciation and amortization	(3,957)	(3,148)
Property and equipment, net	5,016	5,819
Lab equipment
Property, Plant and Equipment [Line Items]
Subtotal	3,382	3,069
Leasehold improvements
Property, Plant and Equipment [Line Items]
Subtotal	4,168	4,235
Office equipment and furniture
Property, Plant and Equipment [Line Items]
Subtotal	1,280	1,340
Computer equipment
Property, Plant and Equipment [Line Items]
Subtotal	143	150
Construction in progress
Property, Plant and Equipment [Line Items]
Subtotal	$ 0	$ 173

Property and Equipment, net - N

Property and Equipment, net - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Property, Plant and Equipment [Abstract]
Depreciation and amortization	$ 321	$ 348	$ 972	$ 1,052

Accrued Expenses (Details)

Accrued Expenses (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Payables and Accruals [Abstract]
Accrued research and development expenses	$ 32,743	$ 36,261
Accrued employee expenses	10,826	14,477
Accrued general and administrative expenses	422	1,032
Lease liability	2,809	2,623
Contingent consideration	500	500
Income Taxes payable	152	281
Accrued legal expenses	219	1,047
Total accrued expenses	47,671	56,221
Less long-term portion	996	1,780
Total accrued expenses	$ 46,675	$ 54,441

Stockholders_ Equity - Narrativ

Stockholders’ Equity - Narrative (Details) - USD ($)		1 Months Ended	9 Months Ended
	Jun. 15, 2023	Apr. 30, 2020	Sep. 30, 2024	Sep. 30, 2023	Jul. 31, 2022
Class of Stock [Line Items]
Issuance of common stock upon exercise of options, net (less than) (in shares)			1,000
Shares issued upon vesting of certain RSAs (less than) (in shares)			1,000
Stock Options
Class of Stock [Line Items]
Generally expected vesting term of the option contract (in years)			10 years
Expected dividend yield			0%	0%
Options outstanding (in shares)			11,200,000
Employee Stock Purchase Plan
Class of Stock [Line Items]
Number of shares reserved for future issuance (in shares)			1,865,179
Expected dividend yield			0%
ESPP maximum percent of compensation to contribute			20%
Maximum contribution amount			$ 25,000
ESPP purchase price of common stock, percent of market price			85%
Offering period (in months)			6 months
RSUs
Class of Stock [Line Items]
Non-option equity instruments, outstanding (in shares)			2,000,000
The 2020 Plan
Class of Stock [Line Items]
Non-option equity instruments, outstanding (in shares)			10,462,700
Number of shares available for future grants (in shares)			3,816,197
2022 Inducement Plan
Class of Stock [Line Items]
Non-option equity instruments, outstanding (in shares)			2,704,400
Number of shares available for future grants (in shares)			545,600
Number of shares reserved for future issuance (in shares)					3,275,000
Follow On Offering
Class of Stock [Line Items]
Gross proceeds from issuance of common stock	$ 250,000,000
Expenses and fees from the issuance of common stock	$ 14,300,000
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%
Common Stock | Follow On Offering
Class of Stock [Line Items]
Number of shares issued and sold (in shares)	11,032,656
Share price (in dollars per share)	$ 22.66
Common Class B | The 2020 Plan | Maximum
Class of Stock [Line Items]
Shares authorized to be issued under plan (in shares)		1,250,000

Stockholders_ Equity - Share-ba

Stockholders’ Equity - Share-based Compensation Expense by Expense Type (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation expense	$ 10,362	$ 13,867	$ 35,906	$ 40,942
Research and development expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation expense	3,083	5,854	11,979	17,712
General and administrative expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation expense	$ 7,279	$ 8,013	$ 23,927	$ 23,230

Stockholders_ Equity - Share-_2

Stockholders’ Equity - Share-based Compensation Expense by Award Type (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation expense	$ 10,362	$ 13,867	$ 35,906	$ 40,942
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation expense	8,357	10,408	27,784	31,222
Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation expense	139	87	330	303
RSAs and RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation expense	$ 1,866	$ 3,372	$ 7,792	$ 9,417

Stockholders_ Equity - Fair Val

Stockholders’ Equity - Fair Value Assumptions for Stock Options (Details) - Stock Options	9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Expected volatility, minimum	75.30%	77.50%
Expected volatility, maximum	78.40%	80.80%
Risk-free interest rate, minimum	3.70%	3.40%
Risk-free interest rate, maximum	4.60%	4.20%
Expected dividend yield	0%	0%
Minimum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Average expected term (in years)	5 years 10 months 24 days	5 years 6 months
Maximum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Average expected term (in years)	6 years 1 month 6 days	6 years 1 month 6 days

Stockholders_ Equity - Fair V_2

Stockholders’ Equity - Fair Value Assumptions for ESPP (Details) - Employee Stock Purchase Plan	9 Months Ended
	Sep. 30, 2024
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Volatility	107.30%
Expected term (years)	6 months
Risk free rate	5.40%
Expected dividend yield	0%

Stockholders_ Equity - Unrecogn

Stockholders’ Equity - Unrecognized Compensation Cost (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2024 USD ($)
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized expense, stock options	$ 68,108
Remaining Weighted-Average Recognition Period (years)	2 years 4 months 28 days
RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized expense, other than stock options	$ 21,453
Remaining Weighted-Average Recognition Period (years)	2 years 9 months 7 days

Commitments and Contingencies -

Commitments and Contingencies - Narrative (Details) $ in Millions	1 Months Ended		9 Months Ended
	Jun. 30, 2024 USD ($)	Dec. 31, 2023 ft²	Sep. 30, 2024 USD ($)
Lessee, Lease, Description [Line Items]
Operating lease, weighted-average remaining lease term (in years)			8 years
Sublease income			$ 1.1
New York City | Building
Lessee, Lease, Description [Line Items]
Area of leased space (in square feet) | ft²		4,115
Gain on lease termination	$ 0.5

Commitments and Contingencies_2

Commitments and Contingencies - Future Minimum Lease Payments (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Commitments and Contingencies Disclosure [Abstract]
2024 (remaining)	$ 1,584
2025	6,799
2026	7,278
2027	7,451
2028	7,760
Thereafter	31,019
Total minimum lease payments:	61,891
Less: imputed interest	(18,625)
Total operating lease liabilities	43,266
Less: current portion	(2,809)	$ (2,623)
Lease liability, net of current portion	$ 40,457	$ 43,150

Net Income (Loss) Per Common _3

Net Income (Loss) Per Common Share - Schedule of Earnings Per Share, Basic and Diluted (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Numerator:
Net Income (Loss) Attributable to Parent	$ (40,158)	$ (55,528)	$ (118,367)	$ (231,274)
Denominator:
Weighted average number of common shares outstanding, basic (in shares)	71,111	70,612	71,017	63,601
Weighted average number of common shares outstanding, diluted (in shares)	71,111	70,612	71,017	63,601
Net loss per common share, basic (in dollars per share)	$ (0.56)	$ (0.79)	$ (1.67)	$ (3.64)
Net loss per common share, diluted (in dollars per share)	$ (0.56)	$ (0.79)	$ (1.67)	$ (3.64)

Net Income (Loss) Per Common _4

Net Income (Loss) Per Common Share - Antidilutive Securities (Details) - shares shares in Thousands	9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per unit (in shares)	13,167	11,740
Stock Options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per unit (in shares)	11,214	10,260
RSAs
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per unit (in shares)	0	4
RSUs
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per unit (in shares)	1,953	1,476

Subsequent Events (Details)

Subsequent Events (Details) - Immunome, Inc - USD ($) shares in Millions, $ in Millions	1 Months Ended
	Jan. 31, 2024	Oct. 31, 2024
Subsequent Event [Line Items]
Contract with customer, volume-weighted average price, period	30 days
Value of common stock	$ 25.6
Subsequent Event
Subsequent Event [Line Items]
Contract with customer liability value of shares		1.8
Value of common stock		$ 21.9
Contingent consideration		$ 5