Zentalis Pharmaceuticals (ZNTL) 10-Q 9 Aug 24 2024 Q2 Quarterly report Financial data

Cover

Cover - shares	6 Months Ended
	Jun. 30, 2024	Aug. 07, 2024
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Jun. 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		71,107,967
Entity Central Index Key	0001725160
Amendment Flag	false
Document Fiscal Period Focus	Q2
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2024

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Current assets
Cash and cash equivalents	$ 36,976	$ 28,038
Marketable securities, available-for-sale	389,409	454,881
Prepaid expenses and other current assets	13,231	13,799
Total current assets	439,616	496,718
Property and equipment, net	5,337	5,819
Operating lease right-of-use assets	33,474	35,916
Prepaid expenses and other assets	6,836	6,818
Goodwill	3,736	3,736
Restricted cash	2,681	2,681
Total assets	491,680	551,688
Current liabilities
Accounts payable	20,440	14,926
Accrued expenses	46,252	54,441
Total current liabilities	66,692	69,367
Long-term lease liability	41,318	43,150
Other long-term liabilities	1,089	1,780
Total liabilities	109,099	114,297
Commitments and contingencies
EQUITY
Preferred stock, $0.001 par value; 10,000,000 shares authorized; no shares issued and outstanding at June 30, 2024 and December 31, 2023	0	0
Common stock, $0.001 par value; 250,000,000 shares authorized; 71,106,719 and 70,765,554 shares issued and outstanding at June 30, 2024 and December 31, 2023, respectively	71	70
Additional paid-in capital	1,349,135	1,323,576
Accumulated other comprehensive income	140	2,194
Accumulated deficit	(966,765)	(888,556)
Total stockholders’ equity	382,581	437,284
Noncontrolling interests	0	107
Total equity	382,581	437,391
Total liabilities and stockholders’ equity	$ 491,680	$ 551,688

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical) - $ / shares	Jun. 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)	71,106,719	70,765,554
Common stock outstanding (in shares)	71,106,719	70,765,554

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Income Statement [Abstract]
License Revenue	$ 0	$ 0	$ 40,560	$ 0
Operating Expenses
Research and development	48,386	42,684	97,971	91,268
Zentera in-process research and development	0	45,568	0	45,568
General and administrative	16,762	15,664	32,502	32,033
Total operating expenses	65,148	103,916	130,473	168,869
Loss from operations	(65,148)	(103,916)	(89,913)	(168,869)
Other Income (Expense)
Investment and other income (expense), net	(22,863)	4,451	12,085	8,560
Net loss before income taxes	(88,011)	(99,465)	(77,828)	(160,309)
Income tax expense (benefit)	266	(605)	409	(497)
Loss on equity method investment	0	13,704	0	16,014
Net loss	(88,277)	(112,564)	(78,237)	(175,826)
Net loss attributable to noncontrolling interests	0	(37)	(28)	(80)
Net loss attributable to Zentalis	$ (88,277)	$ (112,527)	$ (78,209)	$ (175,746)
Net loss per common share outstanding, basic (in dollars per share)	$ (1.24)	$ (1.85)	$ (1.10)	$ (2.93)
Net loss per common share outstanding, diluted (in dollars per share)	$ (1.24)	$ (1.85)	$ (1.10)	$ (2.93)
Common shares used in computing net loss per share, basic (in shares)	71,040	60,790	70,969	60,038
Common shares used in computing net loss per share, diluted (in shares)	71,040	60,790	70,969	60,038

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Comprehensive Loss (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Statement of Comprehensive Income [Abstract]
Net loss	$ (88,277)	$ (112,564)	$ (78,237)	$ (175,826)
Other comprehensive income (loss):
Unrealized income (loss) on marketable securities	(633)	218	(2,054)	1,015
Total comprehensive loss	(88,910)	(112,346)	(80,291)	(174,811)
Comprehensive loss attributable to noncontrolling interests	0	(37)	(28)	(80)
Comprehensive loss attributable to Zentalis	$ (88,910)	$ (112,309)	$ (80,263)	$ (174,731)

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Operating Activities:
Consolidated net loss	$ (88,277)	$ (112,564)	$ (78,237)	$ (175,826)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	327	344	651	704
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	13,704	0	16,014
Share-based compensation			25,544	27,075
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			(2,253)	0
Accretion of discounts on marketable securities, net			(4,960)	(6,483)
Deferred income taxes			0	(853)
Deconsolidation of Kalyra			(79)	0
Changes in operating assets and liabilities:
Prepaid expenses and other assets			550	(3,922)
Accounts payable and accrued liabilities			(3,452)	(5,805)
Operating lease right-of-use assets and liabilities, net			696	544
Net cash used in operating activities			(87,113)	(128,558)
Investing Activities:
Purchases of marketable securities			(29,509)	(189,085)
Proceeds from maturities of marketable securities			125,700	304,457
Proceeds from sale of property and equipment			65	0
Purchases of property and equipment			(221)	(319)
Net cash provided by investing activities			96,035	115,053
Financing Activities:
Proceeds from issuance of common stock, net			0	235,680
Proceeds from issuance of common stock under equity incentive plans			257	1,314
Net-settlement of restricted stock unit vesting			(241)	0
Net cash provided by financing activities			16	236,994
Net increase in cash, cash equivalents and restricted cash			8,938	223,489
Cash, cash equivalents and restricted cash at beginning of period			30,719	45,696
Cash, cash equivalents and restricted cash at end of period	39,657	269,185	39,657	269,185
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents [Abstract]
Cash and cash equivalents	36,976	266,558	36,976	266,558
Restricted cash	2,681	2,627	2,681	2,627
Total cash, cash equivalents and restricted cash reported in the Condensed Consolidated Statement of Cash Flows	$ 39,657	$ 269,185	$ 39,657	$ 269,185

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	27,075		27,075
Other comprehensive (loss) income	1,015			1,015
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)		218,000
Issuance of common stock upon exercise of options, net (in shares)		51,000
Issuance of common stock upon exercise of options, net	941		941
Shares issued under employee stock purchase plan (in shares)		25,000
Shares issued under employee stock purchase plan	373		373
Cancellation of restricted stock awards (in shares)		(3,000)
Net loss attributable to non-controlling interest	(80)					(80)
Net loss attributable to Zentalis	(175,746)				(175,746)
Ending balance (in shares) at Jun. 30, 2023		70,604,000
Ending balance at Jun. 30, 2023	523,282	$ 70	1,295,520	(338)	(772,111)	141
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 Mar. 31, 2023		59,442,000
Beginning balance at Mar. 31, 2023	385,665	$ 59	1,045,568	(556)	(659,584)	178
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Share-based compensation expense	13,342		13,342
Other comprehensive (loss) income	218			218
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)		79,000
Issuance of common stock upon exercise of options, net (in shares)		51,000
Issuance of common stock upon exercise of options, net	941		941
Cancellation of restricted stock awards (in shares)		(1,000)
Net loss attributable to non-controlling interest	(37)					(37)
Net loss attributable to Zentalis	(112,527)				(112,527)
Ending balance (in shares) at Jun. 30, 2023		70,604,000
Ending balance at Jun. 30, 2023	$ 523,282	$ 70	1,295,520	(338)	(772,111)	141
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	25,544		25,544
Other comprehensive (loss) income	(2,054)			(2,054)
Issuance and withholding of common stock in connection with restricted stock unit vesting, net (in shares)		322,000
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)		18,000
Shares issued under employee stock purchase plan	248		248
Net loss attributable to non-controlling interest	(28)					(28)
Net loss attributable to Zentalis	$ (78,209)				(78,209)
Ending balance (in shares) at Jun. 30, 2024	71,106,719	71,107,000
Ending balance at Jun. 30, 2024	$ 382,581	$ 71	1,349,135	140	(966,765)	0
Beginning balance (in shares) at Mar. 31, 2024		71,013,000
Beginning balance at Mar. 31, 2024	458,771	$ 70	1,336,416	773	(878,488)	0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Share-based compensation expense	12,711		12,711
Other comprehensive (loss) income	(633)			(633)
Issuance and withholding of common stock in connection with restricted stock unit vesting, net (in shares)		94,000
Issuance and withholding of common stock in connection with restricted stock unit vesting, net	1	$ 1
Issuance of common stock upon exercise of options, net	8		8
Net loss attributable to non-controlling interest	0
Net loss attributable to Zentalis	$ (88,277)				(88,277)
Ending balance (in shares) at Jun. 30, 2024	71,106,719	71,107,000
Ending balance at Jun. 30, 2024	$ 382,581	$ 71	$ 1,349,135	$ 140	$ (966,765)	$ 0

Organization and Business

Organization and Business	6 Months Ended
	Jun. 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	6 Months Ended
	Jun. 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 June 30, 2024 using the qualitative and quantitative assessment and determined that no impairment existed, and no charges were recorded. Significant Accounting Policies During the six months ended June 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.

Significant Transactions

Significant Transactions	6 Months Ended
	Jun. 30, 2024
Equity Method Investments and Joint Ventures [Abstract]
Significant Transactions	Significant Transactions Immunome In January 2024, Immunome, Inc. (“Immunome”) and Zentalis Pharmaceuticals, Inc. entered into an exclusive, worldwide license agreement under which Immunome licensed from Zentalis ZPC-21, a preclinical ROR1 antibody-drug conjugate (“ADC”) and stock issuance agreement (the “Stock Issuance Agreement”). The upfront consideration from Immunome amounted to $15.0 million in cash and $20.0 million in shares of Immunome common stock, with the shares valued at the trailing 30-day volume-weighted average price. On the date of execution of the transaction, the Immunome common stock was valued at $25.6 million. The performance obligation associated with this upfront payment was met as of March 31, 2024, and $40.6 million, comprised of cash and the fair value of the Immunome stock on the date of execution of the transaction, was recognized as license revenue, within the condensed consolidated statement of operations. The stock acquired was recorded at fair value on the date of acquisition, within marketable securities, available for sale on the condensed consolidated balance sheet. Pursuant to the terms of the Stock Issuance Agreement, Zentalis agreed to hold and not sell greater than 50% of the shares until the six-month anniversary of the closing date, subject to certain exceptions. Changes in fair value of the Immunome stock for the three and six months ended June 30, 2024 amounted to a reduction of $28.9 million and an increase of $2.3 million, respectively, recorded as a component of investment and other income, net within the condensed consolidated statement of operations. There were no disposals of the acquired stock during the three and six months ended June 30, 2024.

Business Combinations

Business Combinations	6 Months Ended
	Jun. 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 with 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 June 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): June 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	6 Months Ended
	Jun. 30, 2024
Fair Value Disclosures [Abstract]
Fair Value Measurement	Fair Value Measurement Available-for-sale marketable debt securities consisted of the following (in thousands): June 30, 2024 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value Commercial paper $ 15,337 $ 1 $ (2) $ 15,336 Corporate debt securities 251,641 246 (76) 251,811 US government agencies 40,940 1 (10) 40,931 US treasury securities 53,539 1 (22) 53,518 $ 361,457 $ 249 $ (110) $ 361,596 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 June 30, 2024, twenty-two of our available-for-sale debt securities with a fair market value of $193.9 million were in a gross unrealized loss position of $0.1 million. Twenty-one have been in a gross unrealized loss position of $0.1 million for less than one year and one has been in a gross unrealized loss position of less than $0.1 million 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 June 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): June 30, 2024 December 31, 2023 Estimated Fair Value Due within one year $ 272,370 $ 267,336 After one but within five years 89,226 187,545 $ 361,596 $ 454,881 The Company had $0.5 million in contingent consideration liabilities as of June 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 June 30, 2024 and December 31, 2023 (in thousands): June 30, 2024 Level 1 Level 2 Level 3 Total estimated fair value Financial assets: Cash equivalents: Money market funds $ 11,256 $ — $ — $ 11,256 Total cash equivalents: 11,256 — — 11,256 Available-for-sale marketable securities: Commercial paper — 15,336 — 15,336 Corporate debt securities — 251,811 — 251,811 US government agencies — 40,931 — 40,931 US treasury securities — 53,518 — 53,518 Immunome equity securities 27,813 — — 27,813 Total available-for-sale marketable securities: 27,813 361,596 — 389,409 Total assets measured at fair value $ 39,069 $ 361,596 $ — $ 400,665 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 The following significant unobservable inputs were used in the valuation of the contingent consideration payable to Zentera pursuant to the Termination Agreement at June 30, 2024: Contingent Consideration Liability Fair Value as of June 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 June 30, 2024 $ 500

Prepaid Expenses and Other Asse

Prepaid Expenses and Other Assets	6 Months Ended
	Jun. 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): June 30, December 31, 2024 2023 Prepaid insurance $ 778 $ 747 Prepaid software licenses and maintenance 566 691 Foreign R&D credit refund 821 500 Prepaid research and development expenses 12,567 13,640 Interest receivable 3,279 3,337 Sublease assets 819 1,471 Other prepaid expenses 1,237 231 Total prepaid expenses and other assets 20,067 20,617 Less long-term portion 6,836 6,818 Total prepaid expenses and other assets, current $ 13,231 $ 13,799

Property and Equipment, net

Property and Equipment, net	6 Months Ended
	Jun. 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): June 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 (3,636) (3,148) Property and equipment, net $ 5,337 $ 5,819 Depreciation and amortization expense for the three months ended June 30, 2024 and 2023 was approximately $327 thousand and $344 thousand, respectively. Depreciation and amortization expense for the six months ended June 30, 2024 and 2023 was $651 thousand and $704 thousand, respectively.

Accrued Expenses

Accrued Expenses	6 Months Ended
	Jun. 30, 2024
Payables and Accruals [Abstract]
Accrued Expenses	Accrued Expenses Accrued expenses consist of the following (in thousands): June 30, December 31, 2024 2023 Accrued research and development expenses $ 36,145 $ 36,261 Accrued employee expenses 6,471 14,477 Accrued general and administrative expenses 612 1,032 Lease liability 2,709 2,623 Contingent consideration 500 500 Income Taxes payable 425 281 Accrued legal expenses 479 1,047 Total accrued expenses 47,341 56,221 Less long-term portion 1,089 1,780 Total accrued expenses $ 46,252 $ 54,441

Stockholders_ Equity

Stockholders’ Equity	6 Months Ended
	Jun. 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 June 30, 2024, 11,480,796 shares were subject to outstanding awards under the 2020 Plan and 2,811,551 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 June 30, 2024, 2,409,816 shares were subject to outstanding awards under the 2022 Inducement Plan and 840,184 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 Six Months Ended 2024 2023 2024 2023 Research and development expense $ 4,155 $ 5,985 $ 8,895 $ 11,858 General and administrative expense 8,556 7,357 16,649 15,217 Total share-based compensation expense $ 12,711 $ 13,342 $ 25,544 $ 27,075 Share-based compensation expense by type of share-based award (in thousands): Three Months Ended Six Months Ended 2024 2023 2024 2023 Stock Options $ 9,553 $ 10,205 $ 19,427 $ 20,814 Employee Stock Purchase Plan 138 111 191 216 RSAs and RSUs 3,020 3,026 5,926 6,045 $ 12,711 $ 13,342 $ 25,544 $ 27,075 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 six months ended June 30, 2024 and June 30, 2023 was determined with the following assumptions: June 30, 2024 June 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 3.8% - 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 June 30, 2024 was 1,894,676. 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 June 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): June 30, 2024 Unrecognized Remaining Stock options $ 80,212 2.64 RSUs 28,793 3.01 ESPP $ 140 0.25

Commitments and Contingencies

Commitments and Contingencies	6 Months Ended
	Jun. 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 June 30, 2024 are as follows (in thousands): Year Operating Leases 2024 (remaining) $ 3,330 2025 6,799 2026 7,278 2027 7,451 2028 7,760 Thereafter 31,019 Total minimum lease payments: 63,637 Less: imputed interest (19,610) Total operating lease liabilities 44,027 Less: current portion (2,709) Lease liability, net of current portion $ 41,318 The weighted-average remaining lease term of our operating leases is approximately 8.3 years.

Net Income (Loss) Per Common Sh

Net Income (Loss) Per Common Share	6 Months Ended
	Jun. 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 Six Months Ended 2024 2023 2024 2023 Numerator: Net income (loss) attributable to Zentalis $ (88,277) $ (112,527) $ (78,209) $ (175,746) Denominator: Weighted average number of common shares outstanding, basic and diluted 71,040 60,790 70,969 60,038 Net loss per common share $ (1.24) $ (1.85) $ (1.10) $ (2.93) 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). June 30, 2024 2023 Outstanding stock options 11,488 10,085 Unvested RSAs — 42 Unvested RSUs 2,403 1,499 13,891 11,626

Pay vs Performance Disclosure

Pay vs Performance Disclosure - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Pay vs Performance Disclosure
Net loss attributable to Zentalis	$ (88,277)	$ (112,527)	$ (78,209)	$ (175,746)

Insider Trading Arrangements

Insider Trading Arrangements	3 Months Ended	6 Months Ended
	Jun. 30, 2024 shares	Jun. 30, 2024 shares
Trading Arrangements, by Individual
Rule 10b5-1 Arrangement Adopted	false
Non-Rule 10b5-1 Arrangement Adopted	false
Non-Rule 10b5-1 Arrangement Terminated	false
Diana Hausman, M.D [Member]
Trading Arrangements, by Individual
Material Terms of Trading Arrangement		On May 2, 2024, a Rule 10b5-1 trading arrangement intended to satisfy the affirmative defense of Rule 10b5-1(c), originally adopted on December 5, 2023 by Diana Hausman, M.D., the Company’s former Chief Medical Officer, for the sale of up to 13,244 shares of the Company’s common stock until May 31, 2025, was terminated.
Name	Diana Hausman, M.D
Title	Chief Medical Officer
Rule 10b5-1 Arrangement Terminated	true
Termination Date	May 2, 2024
Aggregate Available	13,244	13,244
Jan Skvarka [Member]
Trading Arrangements, by Individual
Material Terms of Trading Arrangement		On June 17, 2024, a Rule 10b5-1 trading arrangement intended to satisfy the affirmative defense of Rule 10b5-1(c), originally adopted on November 16, 2023 by Jan Skvarka, a member of the Company’s Board of Directors, for the sale of up to 11,368 shares of the Company’s common stock until December 31, 2024, was terminated.
Name	Jan Skvarka
Title	Board of Directors
Rule 10b5-1 Arrangement Terminated	true
Termination Date	June 17, 2024
Aggregate Available	11,368	11,368

Interim Unaudited Financial S_2

Interim Unaudited Financial Statements (Policies)	6 Months Ended
	Jun. 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.

Business Combinations (Tables)

Business Combinations (Tables)	6 Months Ended
	Jun. 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): June 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)	6 Months Ended
	Jun. 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): June 30, 2024 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value Commercial paper $ 15,337 $ 1 $ (2) $ 15,336 Corporate debt securities 251,641 246 (76) 251,811 US government agencies 40,940 1 (10) 40,931 US treasury securities 53,539 1 (22) 53,518 $ 361,457 $ 249 $ (110) $ 361,596 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): June 30, 2024 December 31, 2023 Estimated Fair Value Due within one year $ 272,370 $ 267,336 After one but within five years 89,226 187,545 $ 361,596 $ 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 June 30, 2024 and December 31, 2023 (in thousands): June 30, 2024 Level 1 Level 2 Level 3 Total estimated fair value Financial assets: Cash equivalents: Money market funds $ 11,256 $ — $ — $ 11,256 Total cash equivalents: 11,256 — — 11,256 Available-for-sale marketable securities: Commercial paper — 15,336 — 15,336 Corporate debt securities — 251,811 — 251,811 US government agencies — 40,931 — 40,931 US treasury securities — 53,518 — 53,518 Immunome equity securities 27,813 — — 27,813 Total available-for-sale marketable securities: 27,813 361,596 — 389,409 Total assets measured at fair value $ 39,069 $ 361,596 $ — $ 400,665 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 June 30, 2024: Contingent Consideration Liability Fair Value as of June 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 June 30, 2024 $ 500

Prepaid Expenses and Other As_2

Prepaid Expenses and Other Assets (Tables)	6 Months Ended
	Jun. 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): June 30, December 31, 2024 2023 Prepaid insurance $ 778 $ 747 Prepaid software licenses and maintenance 566 691 Foreign R&D credit refund 821 500 Prepaid research and development expenses 12,567 13,640 Interest receivable 3,279 3,337 Sublease assets 819 1,471 Other prepaid expenses 1,237 231 Total prepaid expenses and other assets 20,067 20,617 Less long-term portion 6,836 6,818 Total prepaid expenses and other assets, current $ 13,231 $ 13,799

Property and Equipment, net (Ta

Property and Equipment, net (Tables)	6 Months Ended
	Jun. 30, 2024
Property, Plant and Equipment [Abstract]
Summary of Property and Equipment, net	Property and equipment, net consisted of the following (in thousands): June 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 (3,636) (3,148) Property and equipment, net $ 5,337 $ 5,819

Accrued Expenses (Tables)

Accrued Expenses (Tables)	6 Months Ended
	Jun. 30, 2024
Payables and Accruals [Abstract]
Schedule of Accrued Expenses	Accrued expenses consist of the following (in thousands): June 30, December 31, 2024 2023 Accrued research and development expenses $ 36,145 $ 36,261 Accrued employee expenses 6,471 14,477 Accrued general and administrative expenses 612 1,032 Lease liability 2,709 2,623 Contingent consideration 500 500 Income Taxes payable 425 281 Accrued legal expenses 479 1,047 Total accrued expenses 47,341 56,221 Less long-term portion 1,089 1,780 Total accrued expenses $ 46,252 $ 54,441

Stockholders_ Equity (Tables)

Stockholders’ Equity (Tables)	6 Months Ended
	Jun. 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 Six Months Ended 2024 2023 2024 2023 Research and development expense $ 4,155 $ 5,985 $ 8,895 $ 11,858 General and administrative expense 8,556 7,357 16,649 15,217 Total share-based compensation expense $ 12,711 $ 13,342 $ 25,544 $ 27,075 Share-based compensation expense by type of share-based award (in thousands): Three Months Ended Six Months Ended 2024 2023 2024 2023 Stock Options $ 9,553 $ 10,205 $ 19,427 $ 20,814 Employee Stock Purchase Plan 138 111 191 216 RSAs and RSUs 3,020 3,026 5,926 6,045 $ 12,711 $ 13,342 $ 25,544 $ 27,075
Schedule of Fair Value Assumptions for Stock Options	The fair value of the stock options granted during the six months ended June 30, 2024 and June 30, 2023 was determined with the following assumptions: June 30, 2024 June 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 3.8% - 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 June 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): June 30, 2024 Unrecognized Remaining Stock options $ 80,212 2.64 RSUs 28,793 3.01 ESPP $ 140 0.25

Commitments and Contingencies (

Commitments and Contingencies (Tables)	6 Months Ended
	Jun. 30, 2024
Commitments and Contingencies Disclosure [Abstract]
Schedule of Future Minimum Operating Lease Payments	Approximate annual future minimum operating lease payments as of June 30, 2024 are as follows (in thousands): Year Operating Leases 2024 (remaining) $ 3,330 2025 6,799 2026 7,278 2027 7,451 2028 7,760 Thereafter 31,019 Total minimum lease payments: 63,637 Less: imputed interest (19,610) Total operating lease liabilities 44,027 Less: current portion (2,709) Lease liability, net of current portion $ 41,318

Net Income (Loss) Per Common _2

Net Income (Loss) Per Common Share (Tables)	6 Months Ended
	Jun. 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 Six Months Ended 2024 2023 2024 2023 Numerator: Net income (loss) attributable to Zentalis $ (88,277) $ (112,527) $ (78,209) $ (175,746) Denominator: Weighted average number of common shares outstanding, basic and diluted 71,040 60,790 70,969 60,038 Net loss per common share $ (1.24) $ (1.85) $ (1.10) $ (2.93)
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). June 30, 2024 2023 Outstanding stock options 11,488 10,085 Unvested RSAs — 42 Unvested RSUs 2,403 1,499 13,891 11,626

Significant Transactions (Detai

Significant Transactions (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended			6 Months Ended
	Jan. 31, 2024	Jun. 30, 2024	Mar. 31, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Schedule of Equity Method Investments [Line Items]
License Revenue		$ 0		$ 0	$ 40,560	$ 0
Fair value of the Immunome stock, increase (reduction)		(22,863)		$ 4,451	12,085	$ 8,560
Immunome, Inc
Schedule of Equity Method Investments [Line Items]
Upfront consideration, cash	$ 15,000
Upfront consideration, value of shares	$ 20,000
Trailing volume-weighted average price period (in days)	30 days
Value of common stock	$ 25,600
License Revenue			$ 40,600
Percent of shares to be hold and not sold	50%
Anniversary term of shares to be held and not sold (in months)	6 months
Fair value of the Immunome stock, increase (reduction)		$ (28,900)			$ 2,300

Business Combinations - Narrati

Business Combinations - Narrative (Details) - USD ($)	Dec. 21, 2017	Jun. 30, 2024	Dec. 31, 2023
Variable Interest Entity [Line Items]
Assets		$ 491,680,000	$ 551,688,000
Liabilities		109,099,000	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		6 Months Ended		12 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 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 interests	$ 0	$ (37)	(28)	$ (80)
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 interests			(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	Jun. 30, 2024	Dec. 31, 2023
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 361,457	$ 452,686
Gross Unrealized Gains	249	2,299
Gross Unrealized Losses	(110)	(104)
Estimated Fair Value	361,596	454,881
Commercial paper
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	15,337	75,227
Gross Unrealized Gains	1	60
Gross Unrealized Losses	(2)	(15)
Estimated Fair Value	15,336	75,272
Corporate debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	251,641	229,896
Gross Unrealized Gains	246	2,036
Gross Unrealized Losses	(76)	0
Estimated Fair Value	251,811	231,932
US government agencies
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	40,940	83,025
Gross Unrealized Gains	1	100
Gross Unrealized Losses	(10)	(78)
Estimated Fair Value	40,931	83,047
US treasury securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	53,539	64,538
Gross Unrealized Gains	1	103
Gross Unrealized Losses	(22)	(11)
Estimated Fair Value	$ 53,518	$ 64,630

Fair Value Measurement - Narrat

Fair Value Measurement - Narrative (Details) $ in Thousands	Jun. 30, 2024 USD ($) security potential_milestone_payment	Dec. 31, 2023 USD ($)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Number of available-for-sale securities in unrealized loss position | security	22
Debt securities fair market value	$ 193,900
Fair market value of available-for-sale securities in unrealized loss position	$ 100
Number of available-for-sale securities in unrealized loss position for less than one year | security	21
Gross unrealized loss position for less than one year	$ 100
Number of available-for-sale securities in unrealized loss position for more than one year | security	1
Gross unrealized loss position for more than one year (less than)	$ 100
Contingent consideration	500	$ 500
Zentera | Collaborative Arrangement, Transaction with Party to Collaborative Arrangement
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Contingent consideration	$ 500
Number of potential milestone payments | potential_milestone_payment	1

Fair Value Measurement - Contra

Fair Value Measurement - Contractual Maturities of Available-for-sale Debt Securities (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Fair Value Disclosures [Abstract]
Due within one year	$ 272,370	$ 267,336
After one but within five years	89,226	187,545
Total	$ 361,596	$ 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	Jun. 30, 2024	Dec. 31, 2023
Financial assets:
Cash equivalents	$ 11,256	$ 4,755
Marketable securities, available-for-sale	361,596	454,881
Immunome equity securities	27,813
Total available-for-sale marketable securities:	389,409	454,881
Total assets measured at fair value	400,665	459,636
Financial liabilities:
Contingent consideration	500	500
Total financial liabilities	500	500
Level 1
Financial assets:
Cash equivalents	11,256	4,755
Immunome equity securities	27,813
Total available-for-sale marketable securities:	27,813	0
Total assets measured at fair value	39,069	4,755
Financial liabilities:
Contingent consideration	0	0
Total financial liabilities	0	0
Level 2
Financial assets:
Cash equivalents	0	0
Immunome equity securities	0
Total available-for-sale marketable securities:	361,596	454,881
Total assets measured at fair value	361,596	454,881
Financial liabilities:
Contingent consideration	0	0
Total financial liabilities	0	0
Level 3
Financial assets:
Cash equivalents	0	0
Immunome equity securities	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	15,336	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	15,336	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	251,811	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	251,811	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	40,931	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	40,931	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	53,518	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	53,518	64,630
US treasury securities | Level 3
Financial assets:
Marketable securities, available-for-sale	0	0
Money market funds
Financial assets:
Cash equivalents	11,256	4,755
Money market funds | Level 1
Financial assets:
Cash equivalents	11,256	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	Jun. 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	6 Months Ended
	Jun. 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	Jun. 30, 2024	Dec. 31, 2023
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Prepaid insurance	$ 778	$ 747
Prepaid software licenses and maintenance	566	691
Foreign R&D credit refund	821	500
Prepaid research and development expenses	12,567	13,640
Interest receivable	3,279	3,337
Sublease assets	819	1,471
Other prepaid expenses	1,237	231
Total prepaid expenses and other assets	20,067	20,617
Less long-term portion	6,836	6,818
Total prepaid expenses and other assets, current	$ 13,231	$ 13,799

Property and Equipment, net - S

Property and Equipment, net - Summary (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Property, Plant and Equipment [Line Items]
Subtotal	$ 8,973	$ 8,967
Accumulated depreciation and amortization	(3,636)	(3,148)
Property and equipment, net	5,337	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		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Property, Plant and Equipment [Abstract]
Depreciation and amortization	$ 327	$ 344	$ 651	$ 704

Accrued Expenses (Details)

Accrued Expenses (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Payables and Accruals [Abstract]
Accrued research and development expenses	$ 36,145	$ 36,261
Accrued employee expenses	6,471	14,477
Accrued general and administrative expenses	612	1,032
Lease liability	2,709	2,623
Contingent consideration	500	500
Income Taxes payable	425	281
Accrued legal expenses	479	1,047
Total accrued expenses	47,341	56,221
Less long-term portion	1,089	1,780
Total accrued expenses	$ 46,252	$ 54,441

Stockholders_ Equity - Narrativ

Stockholders’ Equity - Narrative (Details) - USD ($)		1 Months Ended	6 Months Ended
	Jun. 15, 2023	Apr. 30, 2020	Jun. 30, 2024	Jun. 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)			11,500,000
Employee Stock Purchase Plan
Class of Stock [Line Items]
Number of shares reserved for future issuance (in shares)			1,894,676
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)			2,400,000
The 2020 Plan
Class of Stock [Line Items]
Non-option equity instruments, outstanding (in shares)			11,480,796
Number of shares available for future grants (in shares)			2,811,551
2022 Inducement Plan
Class of Stock [Line Items]
Non-option equity instruments, outstanding (in shares)			2,409,816
Number of shares available for future grants (in shares)			840,184
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		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation expense	$ 12,711	$ 13,342	$ 25,544	$ 27,075
Research and development expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation expense	4,155	5,985	8,895	11,858
General and administrative expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation expense	$ 8,556	$ 7,357	$ 16,649	$ 15,217

Stockholders_ Equity - Share-_2

Stockholders’ Equity - Share-based Compensation Expense by Award Type (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation expense	$ 12,711	$ 13,342	$ 25,544	$ 27,075
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation expense	9,553	10,205	19,427	20,814
Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation expense	138	111	191	216
RSAs and RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation expense	$ 3,020	$ 3,026	$ 5,926	$ 6,045

Stockholders_ Equity - Fair Val

Stockholders’ Equity - Fair Value Assumptions for Stock Options (Details) - Stock Options	6 Months Ended
	Jun. 30, 2024	Jun. 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	3.80%	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	6 Months Ended
	Jun. 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	6 Months Ended
	Jun. 30, 2024 USD ($)
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized expense, stock options	$ 80,212
Remaining Weighted-Average Recognition Period (years)	2 years 7 months 20 days
RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized expense, other than stock options	$ 28,793
Remaining Weighted-Average Recognition Period (years)	3 years 3 days
ESPP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized expense, other than stock options	$ 140
Remaining Weighted-Average Recognition Period (years)	3 months

Commitments and Contingencies -

Commitments and Contingencies - Narrative (Details) $ in Millions	1 Months Ended		6 Months Ended
	Jun. 30, 2024 USD ($)	Dec. 31, 2023 ft²	Jun. 30, 2024 USD ($)
Lessee, Lease, Description [Line Items]
Operating lease, weighted-average remaining lease term (in years)	8 years 3 months 18 days		8 years 3 months 18 days
Sublease income			$ 0.7
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	Jun. 30, 2024	Dec. 31, 2023
Commitments and Contingencies Disclosure [Abstract]
2024 (remaining)	$ 3,330
2025	6,799
2026	7,278
2027	7,451
2028	7,760
Thereafter	31,019
Total minimum lease payments:	63,637
Less: imputed interest	(19,610)
Total operating lease liabilities	44,027
Less: current portion	(2,709)	$ (2,623)
Lease liability, net of current portion	$ 41,318	$ 43,150

Net Income (Loss) Per Common _3

Net Income (Loss) Per Common Share - Schedule of Basic and Diluted Net Income (Loss) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Numerator:
Net income (loss) attributable to Zentalis	$ (88,277)	$ (112,527)	$ (78,209)	$ (175,746)
Denominator:
Weighted average number of common shares outstanding for basic (in shares)	71,040	60,790	70,969	60,038
Weighted average number of common shares outstanding for diluted earnings per share (in shares)	71,040	60,790	70,969	60,038
Net loss per common share, basic (in dollars per share)	$ (1.24)	$ (1.85)	$ (1.10)	$ (2.93)
Net loss per common share, diluted (in dollars per share)	$ (1.24)	$ (1.85)	$ (1.10)	$ (2.93)

Net Income (Loss) Per Common _4

Net Income (Loss) Per Common Share - Antidilutive Securities (Details) - shares shares in Thousands	6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per unit (in shares)	13,891	11,626
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)	11,488	10,085
Unvested RSAs
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per unit (in shares)	0	42
Unvested RSUs
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per unit (in shares)	2,403	1,499