UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 10-Q

(Mark One)

☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES AND EXCHANGE ACT OF 1934

For the quarterly period ended March 31, 2024

OR

☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES AND EXCHANGE ACT OF 1934

For the transition period from to

Commission File Number: 001-38915

IDEAYA Biosciences, Inc.

(Exact name of registrant as specified in its charter)

Delaware	47-4268251
(State or other jurisdiction of incorporation or organization)	(I.R.S. Employer Identification No.)
7000 Shoreline Court, Suite 350 South San Francisco, California	94080
(Address of principal executive offices)	(Zip Code)

(650) 443-6209

(telephone number, including area code)

Securities registered pursuant to Section 12(b) of the Act:

Title of each class	Trading Symbol(s)	Name of each exchange on which registered
Common Stock, $0.0001 par value per share	IDYA	Nasdaq Global Select Market

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. Yes ☒ No ☐

Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§ 232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files). Yes ☒ No ☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and “emerging growth company” in Rule 12b-2 of the Exchange Act.

Large accelerated filer	☒	Accelerated filer	☐
Non-accelerated filer	☐	Smaller reporting company	☐
		Emerging growth company	☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act). Yes ☐ No ☒

As of May 3, 2024, the registrant had 75,686,628 shares of common stock, $0.0001 par value per share, outstanding.

NOTE REGARDING FORWARD-LOOKING STATEMENTS

This Quarterly Report on Form 10-Q contains forward-looking statements. We intend such forward-looking statements to be covered by the safe harbor provisions for forward-looking statements contained in Section 27A of the Securities Act of 1933, as amended (the “Securities Act”), and Section 21E of the Securities Exchange Act of 1934, as amended (the “Exchange Act”). All statements other than statements of historical facts contained in this Form 10-Q, including statements regarding our future results of operations and financial position, business strategy, prospective products, product approvals, research and development costs, timing and likelihood of success, plans and objectives of management for future operations and future results of anticipated products, are forward-looking statements. These statements involve known and unknown risks, uncertainties and other important factors that may cause our actual results, performance or achievements to be materially different from any future results, performance or achievements expressed or implied by the forward-looking statements.

In some cases, you can identify forward-looking statements by terms such as “may,” “will,” “should,” “expect,” “plan,” “anticipate,” “could,” “intend,” “target,” “project,” “contemplate,” “believe,” “estimate,” “predict,” “potential” or “continue” or the negative of these terms or other similar expressions. The forward-looking statements in this Quarterly Report on Form 10-Q are only predictions. We have based these forward-looking statements largely on our current expectations and projections about future events and financial trends that we believe may affect our business, financial condition and results of operations. These forward-looking statements speak only as of the date of this Quarterly Report on Form 10-Q and are subject to a number of risks, uncertainties and assumptions described under the sections in this Quarterly Report on Form 10-Q entitled “Risk Factors” and “Management’s Discussion and Analysis of Financial Condition and Results of Operations” and elsewhere in this Quarterly Report on Form 10-Q. These forward-looking statements are subject to numerous risks, including, without limitation, the following:

•the scope, progress, results and costs of developing our product candidates or any other future product candidates, and conducting preclinical studies and clinical trials, including our darovasertib Phase /2/3 clinical trials, IDE397 Phase 1/2 clinical trials, IDE161 Phase 1 clinical trial and our GSK101 (IDE705) clinical trial;

•our clinical and regulatory development plans;

•the scope, progress, results and costs related to the research and development of our precision medicine target and biomarker discovery platform, including costs related to the development of our proprietary libraries and database of tumor genetic information and specific cancer-target dependency networks;

•our expectations about the impact of macroeconomic developments, such as health epidemics or pandemics, macro-economic uncertainties, social unrest, geopolitical hostilities, natural disasters or other catastrophic events, on our business, and operations, including clinical trials, manufacturing suppliers and collaborators, and on our results of operations and financial condition;

•the availability of companion diagnostics for biomarkers associated with our product candidates and any future product candidates, or the cost of coordinating and/or collaborating with certain diagnostic companies for the manufacture and supply of companion diagnostics;

•the timing of and costs involved in obtaining and maintaining regulatory approval (or certification in certain foreign jurisdictions) for any of current or future product candidates and companion diagnostics, and any related restrictions, limitations, and/or warnings in the label of an approved product candidate;

•our expectations regarding the potential market size and size of the potential patient populations for darovasertib, IDE397, IDE161, our other product candidates and any future product candidates, if approved for commercial use;

•the timing and amount of any option exercised, milestone, royalty or other payments we may or may not receive pursuant to any current or future collaboration or license agreement, including under the Collaboration, Option and License Agreement with an affiliate of GSK plc, GLAXOSMITHKLINE INTELLECTUAL PROPERTY (NO. 4), Limited (“GSK”);

•our ability to maintain existing, and establish new, strategic collaborations, licensing or other arrangements and the financial terms of any such agreements, including our Collaboration, Option and License Agreement with GSK, our Clinical Supply and Collaboration Agreement with Gilead Sciences, Inc., our Clinical Trial Collaboration and Supply Agreement with MSD International Business GmbH, our Clinical

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Trial Collaboration and Supply Agreements with Pfizer Inc., our Clinical Trial Collaboration and Supply Agreement with Amgen Inc., our License Agreement with Novartis and our Option and License Agreement with Cancer Research Technologies Ltd. (“CRT”), and University of Manchester;

•the timing of commencement of future nonclinical studies and clinical trials and research and development programs;

•our ability to acquire, discover, develop and advance product candidates into, and successfully complete, clinical trials;

•our intentions and our ability to establish collaborations and/or partnerships;

•the timing or likelihood of regulatory filings and approvals for our product candidates;

•our commercialization, marketing and manufacturing capabilities and expectations;

•our intentions with respect to the commercialization of our product candidates;

•the pricing and reimbursement of our product candidates, if approved;

•the implementation of our business model and strategic plans for our business, product candidates and technology platforms, including additional indications for which we may pursue;

•the scope of protection we are able to establish and maintain for intellectual property rights covering our product candidates, including the projected terms of patent protection;

•our potential involvement in lawsuits in connection with enforcing our intellectual property rights;

•our potential involvement in third party interference, opposition, derivation or similar proceedings with respect to our patent rights and other challenges to our patent rights and patent infringement claims;

•estimates of our expenses, future revenue, capital requirements, our needs for additional financing and our ability to obtain additional capital;

•our future financial performance; and

•developments and projections relating to our competitors and our industry, including competing therapies and procedures.

Moreover, we operate in an evolving environment. New risk factors and uncertainties may emerge from time to time, and it is not possible for management to predict all risk factors and uncertainties.

Because forward-looking statements are inherently subject to risks and uncertainties, some of which cannot be predicted or quantified and some of which are beyond our control, you should not rely on these forward-looking statements as predictions of future events. The events and circumstances reflected in our forward-looking statements may not occur or be achieved, and actual results could differ materially from those projected in the forward-looking statements. We qualify all of our forward-looking statements by these cautionary statements. Except as required by applicable law, we do not plan to publicly update or revise any forward-looking statements contained herein, whether as a result of any new information, future events, changed circumstances or otherwise.

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IDEAYA Biosciences, Inc.

Form 10-Q for Quarterly Period Ended March 31, 2024

Table of Contents

PART I—FINANCIAL INFORMATION	4
Item 1. Financial Statements (Unaudited)	4
Condensed Balance Sheets	4
Condensed Statements of Operations and Comprehensive Loss	5
Condensed Statements of Stockholders’ Equity	6
Condensed Statements of Cash Flows	7
Notes to Condensed Financial Statements (Unaudited)	8
Item 2. Management’s Discussion and Analysis of Financial Condition and Results of Operations	26
Item 3. Quantitative and Qualitative Disclosures About Market Risk	44
Item 4. Controls and Procedures	44
PART II—OTHER INFORMATION	45
Item 1. Legal Proceedings	45
Item 1A. Risk Factors	45
Item 2. Unregistered Sales of Equity Securities and Use of Proceeds	46
Item 3. Defaults Upon Senior Securities	46
Item 4. Mine Safety Disclosures	46
Item 5. Other information	46
Item 6. Exhibits	47
SIGNATURES	48

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PART I—FINANCIAL INFORMATION

Item 1. Financial Statements (UNAUDITED).

IDEAYA Biosciences, Inc.

Condensed Balance Sheets

(in thousands, except share and per share amounts)

(Unaudited)

	March 31,			December 31,
	2024			2023
Assets
Current assets
Cash and cash equivalents	$	108,345		$	157,018
Short-term marketable securities		590,427			368,096
Accounts receivable		15			18
Prepaid expenses and other current assets		10,566			7,500
Total current assets		709,353			532,632
Restricted cash		757			757
Long-term marketable securities		242,636			107,492
Property and equipment, net		6,909			6,164
Right-of-use assets		1,780			2,246
Other non-current assets		92			25
Total assets	$	961,527		$	649,316
Liabilities and Stockholders’ Equity
Current liabilities
Accounts payable	$	6,290		$	6,598
Accrued liabilities		17,519			18,756
Operating lease liabilities, current		1,151			1,747
Total current liabilities		24,960			27,101
Long-term operating lease liabilities		1,256			1,125
Total liabilities		26,216			28,226
Commitments and contingencies (Note 6)
Stockholders’ equity
Preferred stock, $0.0001 par value, 10,000,000 shares authorized as of    March 31, 2024 and December 31, 2023; no shares issued and    outstanding as of March 31, 2024 and December 31, 2023		—			—
Common stock, $0.0001 par value, 300,000,000 shares authorized as of    March 31, 2024 and December 31, 2023; 74,764,628 and 65,039,369     shares issued and outstanding as of March 31, 2024 and    December 31, 2023		7			7
Additional paid-in capital		1,324,163			968,885
Accumulated other comprehensive (loss) income		(923	)		562
Accumulated deficit		(387,936	)		(348,364	)
Total stockholders’ equity		935,311			621,090
Total liabilities and stockholders’ equity	$	961,527		$	649,316

The accompanying notes are an integral part of these condensed financial statements.

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IDEAYA Biosciences, Inc.

Condensed Statements of Operations and Comprehensive Loss

(in thousands, except share and per share amounts)

(Unaudited)

	Three Months Ended March 31,
	2024			2023
Collaboration revenue	$	—		$	7,880
Total revenue		—			7,880
Operating expenses
Research and development		42,805			27,859
General and administrative		8,212			6,300
Total operating expenses		51,017			34,159
Loss from operations		(51,017	)		(26,279	)
Other income
Interest income and other income, net		11,445			2,639
Net loss	$	(39,572	)	$	(23,640	)
Unrealized (losses) gains on marketable securities		(1,485	)		1,466
Comprehensive loss	$	(41,057	)	$	(22,174	)
Net loss per common share, basic and diluted	$	(0.53	)	$	(0.49	)
Weighted-average common shares outstanding, basic and diluted		75,108,484			48,370,074

The accompanying notes are an integral part of these condensed financial statements.

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IDEAYA Biosciences, Inc.

Condensed Statements of Stockholders’ Equity

(in thousands, except share amounts)

(Unaudited)

							Accumulated
					Additional		Other						Total
	Common Stock				Paid-In		Comprehensive			Accumulated			Stockholders'
	Shares		Amount		Capital		Income (Loss)			Deficit			Equity
Balances as of December 31, 2023		65,039,369	$	7	$	968,885	$	562		$	(348,364	)	$	621,090
Issuance of common stock related to at-the-market offering program, net of issuance costs		9,260,382		—		343,505								343,505
Issuance of common stock upon exercise of stock options		464,877		—		5,461								5,461
Stock-based compensation						6,312								6,312
Other comprehensive loss								(1,485	)					(1,485	)
Net loss											(39,572	)		(39,572	)
Balances as of March 31, 2024		74,764,628	$	7	$	1,324,163	$	(923	)	$	(387,936	)	$	935,311
Balances as of December 31, 2022		48,193,179	$	5	$	587,724	$	(2,871	)	$	(235,403	)	$	349,455
Issuance of common stock related to at-the-market offering program, net of issuance costs		142,160				2,504								2,504
Issuance of common stock upon exercise of stock options		55,055				366								366
Stock-based compensation						3,659								3,659
Other comprehensive income								1,466						1,466
Net loss											(23,640	)		(23,640	)
Balances as of March 31, 2023		48,390,394	$	5	$	594,253	$	(1,405	)	$	(259,043	)	$	333,810

The accompanying notes are an integral part of these condensed financial statements.

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IDEAYA Biosciences, Inc.

Condensed Statements of Cash Flows

(in thousands)

(Unaudited)

	Three Months Ended March 31,
	2024			2023
Cash flows from operating activities
Net loss	$	(39,572	)	$	(23,640	)
Adjustments to reconcile net loss to net cash used in operating activities
Depreciation and amortization		616			588
Net amortization (accretion) of premiums (discounts) on marketable securities		(6,314	)		(1,557	)
Stock-based compensation		6,312			3,659
Amortization of right-of-use assets		466			372
Changes in assets and liabilities
Accounts receivable		3			(257	)
Prepaid expenses and other assets		(3,133	)		1,373
Accounts payable		(453	)		(12	)
Accrued and other liabilities		(1,273	)		(419	)
Contract liabilities		—			(7,498	)
Lease liabilities		(465	)		(451	)
Net cash used in operating activities		(43,813	)		(27,842	)
Cash flows from investing activities
Purchases of property and equipment, net		(1,325	)		(43	)
Purchases of marketable securities		(475,781	)		(72,296	)
Maturities of marketable securities		123,135			95,860
Net cash (used in) provided by investing activities		(353,971	)		23,521
Cash flows from financing activities
Proceeds from issuance of common stock related to at-the-market offering program, net of issuance costs		343,650			2,560
Proceeds from exercise of common stock options		5,461			366
Net cash provided by financing activities		349,111			2,926
Net decrease in cash, cash equivalents and restricted cash		(48,673	)		(1,395	)
Cash, cash equivalents and restricted cash
Cash, cash equivalents and restricted cash, at beginning of period		157,775			68,738
Cash, cash equivalents and restricted cash, at end of period	$	109,102		$	67,343
Reconciliation of cash, cash equivalents and restricted cash
Cash and cash equivalents	$	108,345		$	67,237
Restricted cash		757			106
Cash, cash equivalents and restricted cash	$	109,102		$	67,343
Supplemental disclosure of cash flow information:
Cash paid for interest	$	12		$	13
Supplemental non-cash investing and financing activities:
Purchases of property and equipment in accounts payable and accrued liabilities	$	183		$	746
Accrued ATM costs	$	145		$	56

The accompanying notes are an integral part of these condensed financial statements.

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IDEAYA Biosciences, Inc.

Notes to Condensed Financial Statements (Unaudited)

1. Organization

Description of the Business

IDEAYA Biosciences, Inc. (the “Company”) is a precision medicine oncology company committed to the discovery and development of targeted therapeutics for patient populations selected using molecular diagnostics. The Company is headquartered in South San Francisco, California and was incorporated in the State of Delaware in June 2015. To date, the Company has been primarily engaged in business planning, research, development, recruiting and raising capital.

Follow-On Offering

On April 27, 2023, the Company completed an underwritten public follow-on offering. The offering consisted of 8,858,121 shares of the Company's common stock, par value $0.0001 per share (“common stock”), at an offering price to the public of $18.50 per share, including 1,418,920 shares of common stock upon the exercise in full of the overallotment option by the underwriters, as well as pre-funded warrants to purchase 2,020,270 shares of common stock at a public offering price of $18.4999 per underlying share, in each case before underwriting discounts and commissions. Pursuant to the offering, the Company received aggregate gross proceeds of approximately $201.3 million, before deducting underwriting discounts and commissions and other offering expenses, resulting in net proceeds of approximately $188.7 million, after deducting underwriting discounts and commissions and other offering expenses.

On October 27, 2023, the Company completed an underwritten public follow-on offering. The offering consisted of 5,797,872 shares of common stock at an offering price to the public of $23.50 per share, including 797,872 shares of common stock upon the exercise in full of the overallotment option by the underwriters, as well as pre-funded warrants to purchase 319,150 shares of common stock at a public offering price of $23.4999 per underlying share, in each case before underwriting discounts and commissions. Pursuant to the offering, the Company received aggregate gross proceeds of approximately $143.7 million, before deducting underwriting discounts and commissions and other offering expenses, resulting in net proceeds of approximately $134.6 million, after deducting underwriting discounts and commissions and other offering expenses.

At-the-Market Offering

On June 26, 2023, the Company filed a new Registration Statement on Form S-3 (File No. 333- 272936) under the Securities Act as an automatic shelf registration statement as a “well-known seasoned issuer”, as defined in Rule 405 under the Securities Act. On June 26, 2023, the Company also entered into a new Open Market Sales Agreement, or June 2023 Sales Agreement, with Jefferies LLC (“Jefferies”) relating to an at-the-market offering program under which the Company may offer and sell, from time to time at its sole discretion, shares of common stock having aggregate gross proceeds of up to $250.0 million through Jefferies as sales agent.

During the reporting period for the quarter ended March 31, 2024, the Company sold an aggregate of 6,115,516 shares of common stock for aggregate net proceeds of $215.9 million at a weighted average sales price of approximately $36.39 per share under the at-the-market offering pursuant to the June 2023 Sales Agreement with Jefferies as sales agent.

On January 19, 2024, the Company entered into a new Open Market Sales Agreement, or January 2024 Sales Agreement, with Jefferies relating to an at-the-market offering program under which the Company may offer and sell, from time to time at its sole discretion, shares of common stock having aggregate gross proceeds of up to $350.0 million through Jefferies as sales agent.

During the reporting period for the quarter ended March 31, 2024, the Company sold an aggregate of 3,144,866 shares of common stock for aggregate net proceeds of $127.6 million at a weighted average sales price of approximately $41.53 per share under the at-the-market offering pursuant to the January 2024 Sales Agreement with Jefferies as sales agent.

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As of March 31, 2024, $219.4 million of common stock remained available to be sold under the at-the-market facility associated with the January 2024 Sales Agreement.

The Company may cancel its at-the-market program at any time upon written notice, pursuant to its terms.

Liquidity

The Company has incurred significant losses and negative cash flows from operations in all periods since inception and had an accumulated deficit of $387.9 million as of March 31, 2024.

The Company has financed its operations primarily through the sale and issuance of common stock and the upfront payment and certain milestone payments received from GSK.

To date, none of the Company’s product candidates have been approved for sale, and the Company has not generated any revenue from commercial products since inception. Management expects operating losses to continue and increase for the foreseeable future, as the Company progresses clinical development activities for its lead product candidates. The Company’s prospects are subject to risks, expenses and uncertainties frequently encountered by companies in the biotechnology industry as discussed under Risks and Uncertainties in Note 2. While the Company has been able to raise multiple rounds of financing, there can be no assurance that in the event the Company requires additional financing, such financing will be available on terms which are favorable or at all. Failure to generate sufficient cash flows from operations, raise additional capital or reduce certain discretionary spending would have a material adverse effect on the Company’s ability to achieve its intended business objectives.

As of March 31, 2024, the Company had cash, cash equivalents and marketable securities of $941.4 million. Management believes that the Company’s current cash, cash equivalents and marketable securities will be sufficient to fund its planned operations for at least 12 months from the date of the issuance of these financial statements.

2. Summary of Significant Accounting Policies

Basis of Presentation

These condensed financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“GAAP”) and the rules and regulations of the United States Securities and Exchange Commission (“SEC”) for interim reporting.

Certain information and footnote disclosures normally included in annual financial statements prepared in accordance with GAAP have been condensed or omitted. Accordingly, the unaudited condensed financial statements should be read in conjunction with the audited financial statements and the related 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 20, 2024.

Unaudited Condensed Financial Statements

The accompanying financial information for the three months ended March 31, 2024 and March 31, 2023 are unaudited. The unaudited condensed financial statements have been prepared on the same basis as the annual audited financial statements and, in the opinion of management, reflect all adjustments, which include only normal recurring adjustments, necessary to present fairly the Company’s financial position as of March 31, 2024 and its results of operations for the three months ended March 31, 2024 and March 31, 2023 and cash flows for the three months ended March 31, 2024 and March 31, 2023. The results for interim periods are not necessarily indicative of the results expected for the full fiscal year or any other periods.

Use of Estimates

The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities as of the date of the financial statements and the reported amounts of revenue and expenses during the reporting period. Such estimates include useful lives of property and equipment, determination of the discount rate for operating leases, accruals for research and development activities, revenue recognition, stock-based

9

compensation, and income taxes. On an ongoing basis, management reviews these estimates and assumptions. Changes in facts and circumstances may alter such estimates and actual results could differ from those estimates.

Risks and Uncertainties

The Company operates in a dynamic and highly competitive industry and is subject to risks and uncertainties common to early-stage companies in the biotechnology industry, including, but not limited to, development by competitors of new technological innovations, protection of proprietary technology, dependence on key personnel, contract manufacturers, contract research organizations and collaboration partners, compliance with government regulations and the need to obtain additional financing to fund operations. Product candidates currently under development will require significant additional research and development efforts, including extensive preclinical studies and clinical trials and regulatory approval, prior to commercialization. These efforts require significant amounts of additional capital, adequate personnel infrastructure and extensive compliance and reporting. The Company believes that changes in any of the following areas could have a material adverse effect on the Company’s future financial position, results of operations, or cash flows: ability to obtain future financing; advances and trends in new technologies and industry standards; results of clinical trials and collaboration activities; regulatory approval and market acceptance of the Company’s products; development of sales channels; certain strategic relationships; litigation or claims against the Company based on intellectual property, patent, product, regulatory, or other factors; and the Company’s ability to attract and retain employees necessary to support its growth.

Products developed by the Company require approvals from the U.S. Food and Drug Administration (“FDA”) or other international regulatory agencies prior to commercial sales. There can be no assurance that the Company’s research and development will be successfully completed, that adequate protection for the Company’s intellectual property will be obtained or maintained, that the products will receive the necessary approvals, or that any approved products will be commercially viable. If the Company was denied approval, approval was delayed or the Company was unable to maintain approval, it could have a materially adverse impact on the Company. Even if the Company’s product development efforts are successful, it is uncertain when, if ever, the Company will generate revenue from product sales. The Company operates in an environment of rapid change in technology and substantial competition from other pharmaceutical and biotechnology companies. In addition, the Company is dependent upon the services of its employees, consultants and other third parties.

The Company has expended and will continue to expend substantial funds to complete the research, development and clinical testing of product candidates. The Company also will be required to expend additional funds to establish commercial-scale manufacturing arrangements and to provide for the marketing and distribution of products that receive regulatory approval. The Company may require additional funds to commercialize its products. The Company is unable to entirely fund these efforts with its current financial resources. If adequate funds are unavailable on a timely basis from operations or additional sources of financing, the Company may have to delay, reduce the scope of or eliminate one or more of its research or development programs which would materially and adversely affect its business, financial condition and operations.

Concentration of Credit Risk

Financial instruments that potentially subject the Company to a concentration of credit risk consist of cash, cash equivalents and marketable securities. Substantially all the Company’s cash is held by two financial institutions that management believes are of high credit quality. Such deposits may, at times, exceed federally insured limits.

The Company’s investment policy addresses credit ratings, diversification, and maturity dates.

The Company invests its cash equivalents and marketable securities in money market funds, U.S. government securities, commercial paper, and corporate bonds. The Company limits its credit risk associated with cash equivalents and marketable securities by placing them with banks and institutions it believes are creditworthy and in highly rated investments and, by policy, limits the amount of credit exposure with any one commercial issuer. The Company has not experienced any credit losses on its deposits of cash, cash equivalents or marketable securities.

Summary of Significant Accounting Policies

There have been no material changes in the accounting policies from those disclosed in the financial statements and the related notes included in the Company's Annual Report on Form 10-K, filed with the SEC on February 20, 2024.

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Recent Accounting Pronouncements

From time to time, new accounting pronouncements are issued by the Financial Accounting Standards Board (“FASB”) under its accounting standard codifications (“ASC”) or other standard setting bodies and adopted by the Company as of the specified effective date, unless otherwise discussed below.

New Accounting Pronouncements, Not yet Adopted:

On October 2023, the FASB issued ASU 2023-06, Disclosure Improvements: Codification Amendments in Response to the SEC's Disclosure Update and Simplification Initiative, which modifies the disclosure or presentation requirements related to variety of FASB Accounting Standard Codification topics. The effective date for each amendment will be the date on which the SEC's removal of that related disclosure from Regulation S-X or Regulation S-K is effective. If by June 30, 2027, the SEC has not removed the applicable requirement from Regulation S-X or Regulation S-K, the pending content of the associated amendment will be removed from the Codification and will not become effective for any entities. The Company is currently evaluating the effect of adopting this ASU.

On December 14, 2023, the FASB issued ASU 2023-09, Improvements to Income Tax Disclosures, which amends the guidance in ASC 740, Income Taxes. The ASU is intended to improve the transparency of income tax disclosures by requiring (1) consistent categories and greater disaggregation of information in the rate reconciliation and (2) income taxes paid disaggregated by jurisdiction. It also includes certain other amendments to improve the effectiveness of income tax disclosures. The ASU’s amendments are effective for public business entities for annual periods beginning after December 15, 2024. Entities are permitted to early adopt the standard “for annual financial statements that have not yet been issued or made available for issuance.” Adoption is either prospectively or retrospectively; the Company will adopt this ASU on a prospective basis. The Company is currently evaluating the impact of the ASU but does not expect any material impacts upon adoption.

3. Fair Value Measurement and Marketable Securities

The Company applies fair value accounting for all financial assets and liabilities and non-financial assets and liabilities that are recognized or disclosed at fair value in the financial statements on a recurring basis. Fair value is an exit price, representing the amount that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants. As such, fair value is a market-based measurement that should be determined based on assumptions that market participants would use in pricing an asset or liability. As a basis for considering such assumptions, a three-tier fair value hierarchy has been established, which prioritizes the inputs used in measuring fair value as follows:

Level 1—Observable inputs, such as quoted prices in active markets for identical assets or liabilities at the measurement date.

Level 2—Observable inputs other than Level 1 prices such as quoted prices for similar assets or liabilities, quoted prices in markets that are not active, or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities.

Level 3—Unobservable inputs which reflect management’s best estimate of what market participants would use in pricing the asset or liability at the measurement date. Consideration is given to the risk inherent in the valuation technique and the risk inherent in the inputs to the model.

In determining fair value, the Company utilizes valuation techniques that maximize the use of observable inputs and minimize the use of unobservable inputs to the extent possible as well as considers counterparty credit risk in its assessment of fair value.

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As of March 31, 2024, financial assets measured and recognized at fair value are as follows (in thousands):

		March 31, 2024
		Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Estimated Fair Value
Assets
U.S. government securities(1)	Level 2	$	519,487	$	71	$	(542	)	$	519,016
Corporate bonds	Level 2		151,971		44		(396	)		151,619
Commercial paper(2)	Level 2		232,426		—		(98	)		232,328
Marketable securities			903,884		115		(1,036	)		902,963
Money market funds(3)	Level 1		37,953							37,953
Total fair value of assets		$	941,837	$	115	$	(1,036	)	$	940,916

(1)$10.9 million was included in cash and cash equivalents on the condensed balance sheets due to securities with purchase dates within 90 days of maturity dates.

(2)$59.0 million was included in cash and cash equivalents on the condensed balance sheets due to securities with purchase dates within 90 days of maturity dates.

(3)Included in cash and cash equivalents on the condensed balance sheets.

As of December 31, 2023, financial assets measured and recognized at fair value are as follows (in thousands):

		December 31, 2023
		Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Estimated Fair Value
Assets
U.S. government securities(1)	Level 2	$	412,679	$	591	$	(135	)	$	413,135
Corporate bonds	Level 2		53,983		197		(32	)		54,148
Commercial paper(2)	Level 2		126,601	—			(58	)		126,543
Marketable securities			593,263		788		(225	)		593,826
Money market funds(3)	Level 1		38,300		—		—			38,300
Total fair value of assets		$	631,563	$	788	$	(225	)	$	632,126

(1)$37.8 million was included in cash and cash equivalents on the condensed balance sheets due to securities with purchase dates within 90 days of maturity dates.

(2)$80.4 million was included in cash and cash equivalents on the condensed balance sheets due to securities with purchase dates within 90 days of maturity dates.

(3)Included in cash and cash equivalents on the condensed balance sheets.

As of March 31, 2024 and December 31, 2023, all marketable securities had a remaining maturity of less than three years. There were no financial liabilities measured and recognized at fair value as of March 31, 2024 and December 31, 2023.

The Company considers available evidence in evaluating potential other-than-temporary impairments of its marketable securities, including the duration and extent to which fair value is less than cost, and the Company’s ability and intent to hold the investment. As of March 31, 2024 and December 31, 2023, the Company held certain securities in an unrealized loss position. These unrealized losses were considered to be temporary as the Company expects to recover the entire amortized cost basis on the securities in unrealized loss positions based on the creditworthiness of the underlying issuer, and the Company neither intends to sell these securities nor considers it more likely than not that the Company would be required to sell any such security before its anticipated recovery. As a result, the Company did not consider any of these investments to be other-than-temporarily impaired at March 31, 2024 and December 31, 2023.

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4. Balance Sheet Components

Property and Equipment, Net

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

	Useful Life	March 31,			December 31,
	(In Years)	2024			2023
Laboratory equipment	5	$	11,636		$	11,455
Computer equipment	3		261			261
Software	3		231			231
Leasehold improvements	Shorter of useful life or lease term		4,115			3,321
Furniture and fixtures	5		832			507
Total property and equipment			17,075			15,775
Less: Accumulated depreciation and amortization			(10,166	)		(9,611	)
Property and equipment, net		$	6,909		$	6,164

Depreciation and amortization expense was $0.6 million and $0.6 million for the three months ended March 31, 2024 and March 31, 2023, respectively.

Accrued Liabilities

Accrued liabilities consisted of the following (in thousands):

	March 31,		December 31,
	2024		2023
Accrued research and development expenses	$	12,220	$	10,676
Accrued salaries and benefits		4,260		6,974
Legal and professional fees		856		959
Other		183		147
Accrued liabilities	$	17,519	$	18,756

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5. Operating Leases

The Company leases its laboratory and office facilities at 7000 Shoreline Court, South San Francisco for approximately 29,000 square feet with an expiration date in September 2024.

In June 2023, the Company entered into a lease agreement for approximately 44,000 square feet of space at 5000 Shoreline Court, South San Francisco, California. The lease term is expected to commence in the third quarter of 2024 and the lease term is one hundred twenty months. The Company has an option to extend the lease term for a total of two consecutive five-year periods.

In November 2023, the Company entered into a lease agreement for approximately 5,700 square feet of space at 11710 El Camino Real, San Diego, California for corporate office space. The lease term commenced in December 2023 and expires in March 2028. The Company has an option to renew the lease for 3 years.

Future minimum lease payments under operating leases included on the Company's condensed balance sheet are as follows:

As of March 31, 2024	Operating Leases
2024	$	1,381
2025		386
2026		398
2027		410
2028		106
Total future minimum lease payments		2,681
Less: imputed interest		(274	)
Total operating lease liabilities	$	2,407

The following table summarizes other information about the Company's operating leases:

	As of
	March 31, 2024			December 31, 2023
Remaining Lease Term		2.3			2.4
Discount Rate		8.3	%		8.0	%

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Operating lease costs were $0.5 million and $0.4 million for the quarters ended March 31, 2024 and March 31, 2023, respectively. Variable lease costs were $0.4 million for the quarters ended March 31, 2024 and March 31, 2023. Variable lease costs represent additional costs incurred, related to administration, maintenance and property tax costs incurred, which are billed based on both usage and as a percentage of the Company's share of total square footage.

During the quarters ended March 31, 2024 and March 31, 2023, cash paid for amounts included in the measurement of lease liabilities and included within cash used in operating activities in the statement of cash flows was $0.5 million.

6. Commitments and Contingencies

Contingencies

From time to time, the Company may be involved in litigation related to claims that arise in the ordinary course of its business activities. The Company accrues for these matters when it is probable that future expenditures will be made and these expenditures can be reasonably estimated. As of March 31, 2024, the Company does not believe that any such matters, individually or in the aggregate, will have a material adverse effect on the Company’s financial position, results of operations or cash flows.

Indemnification

The Company enters into standard indemnification arrangements in the ordinary course of business with vendors, clinical trial sites and other parties. Pursuant to these arrangements, the Company indemnifies, holds harmless and agrees to reimburse the indemnified parties for losses suffered or incurred by the indemnified party. The term of these indemnification agreements is generally perpetual any time after the execution of the agreement. The maximum potential amount of future payments the Company could be required to make under these arrangements is not determinable. The Company has never incurred costs to defend lawsuits or settle claims related to these indemnification agreements. Accordingly, the Company has not recorded a liability related to such indemnification agreements as of March 31, 2024.

7. Income Taxes

For the three months ended March 31, 2024 and March 31, 2023, the Company did not record a federal or state income tax provision due to its recurring net losses. In addition, the Company has taken a full valuation allowance against its net deferred tax assets as the Company believes it is not more likely than not that the benefit will be realized.

The Company is under audit in California for tax years 2020-2021.

8. Common Stock

As of March 31, 2024 and December 31, 2023, the Company’s certificate of incorporation authorized the Company to issue 300,000,000 shares of common stock at a par value of $0.0001 per share. Each share of common stock is entitled to one vote. The holders of common stock are also entitled to receive dividends whenever funds are legally available and when declared by the Company’s board of directors. As of March 31, 2024 and December 31, 2023, no dividends have been declared to date.

On April 27, 2023, the Company completed an underwritten public follow-on offering. The offering consisted of 8,858,121 shares of common stock at an offering price to the public of $18.50 per share, including 1,418,920 shares of common stock upon the exercise in full of the overallotment option by the underwriters, as well as pre-funded warrants to purchase 2,020,270 shares of common stock at a public offering price of $18.4999 per underlying share, in each case before underwriting discounts and commissions. Pursuant to the offering, the Company received aggregate gross proceeds of approximately $201.3 million, before deducting underwriting discounts and commissions and other offering expenses, resulting in net proceeds of approximately $188.7 million, after deducting underwriting discounts and commissions and other offering expenses.

On October 27, 2023, the Company completed an underwritten public follow-on offering. The offering consisted of 5,797,872 shares of common stock at an offering price to the public of $23.50 per share, including 797,872 shares of common stock upon the exercise in full of the overallotment option by the underwriters, as well as pre-funded warrants to purchase 319,150 shares of common stock at a public offering price of $23.4999 per underlying share, in

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each case before underwriting discounts and commissions. Pursuant to the offering, the Company received aggregate gross proceeds of approximately $143.7 million, before deducting underwriting discounts and commissions and other offering expenses, resulting in net proceeds of approximately $134.6 million, after deducting underwriting discounts and commissions and other offering expenses.

As of March 31, 2024, the following aggregate warrants to purchase shares of the Company’s common stock were issued and outstanding:

Issue Date	Expiration Date	Exercise Price per Share	Number of Shares subject to Outstanding Warrants
April 27, 2023	None	$.0001	2,020,270
October 27, 2023	None	$.0001	319,150

The warrants are classified as a component of Stockholders’ Equity within Additional Paid-in-Capital. The warrants are classified as equity because they are freestanding financial instruments that are legally detachable and separately exercisable from the equity instruments, are immediately exercisable, do not embody an obligation for the Company to repurchase its shares, are indexed to the Company’s common stock and meet the equity classification criteria. The warrants will not expire until they are fully exercised. As of March 31, 2024, no shares underlying the warrants had been exercised.

The Company had reserved common stock for future issuance as follows:

	March 31,	December 31,
	2024	2023
Outstanding options under the 2015, 2019 and 2023 Plans	7,874,924	6,269,975
Shares available for grant under the 2019 Plan	1,638,170	964,622
Shares available for grant under the 2023 Inducement Plan	382,500	524,300
Shares available under the Employee Stock Purchase Plan	1,968,367	1,317,974
Pre-funded warrants issued and outstanding	2,339,420	2,339,420
Total	14,203,381	11,416,291

9. Stock-Based Compensation

2023 Inducement Plan

On February 24, 2023, the Company adopted the IDEAYA Biosciences, Inc. 2023 Employment Inducement Award Plan (the “2023 Inducement Plan”), pursuant to which the Company reserved 1,000,000 shares of its common stock to be used exclusively for grants of awards to individuals who were not previously employees or directors of the Company as an inducement material to the individual’s entry into employment with the Company within the meaning of Rule 5635(c)(4) of the Nasdaq Listing Rules. The 2023 Inducement Plan was approved by the Company’s board of directors without stockholder approval in accordance with such rule. Options granted under the 2023 Inducement Plan have a term of 10 years and generally vest over a 4-year period with 1-year cliff vesting.

As of March 31, 2024, the number of shares available for issuance under the 2023 Inducement Plan was 382,500.

2019 Incentive Award Plan

In May 2019, the Company’s board of directors adopted and the Company’s stockholders approved the 2019 Incentive Award Plan (the “2019 Plan”), under which the Company may grant cash and equity-based incentive awards to the Company’s employees, consultants and directors. Following the effectiveness of the 2019 Plan, the Company will not make any further grants under the 2015 Equity Incentive Plan (the “2015 Plan”). However, the 2015 Plan continues to govern the terms and conditions of the outstanding awards granted under it. Shares of common stock subject to awards granted under the 2015 Plan that are forfeited or lapse unexercised and which following the effective date of the 2019 Plan are not issued under the 2015 Plan will be available for issuance under the 2019 Plan.

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Options granted under the 2019 Plan may be either incentive stock options (“ISOs”) or nonqualified stock options (“NSOs”). ISOs may be granted only to Company employees (including officers and directors who are also employees). NSOs may be granted to Company employees, directors and consultants.

The 2019 Plan is subject to an annual increase on the first day of each year beginning in 2020 and ending in 2029, equal to the lesser of 4% of the shares outstanding on the last day of the immediately preceding fiscal year, and such smaller number of shares as determined by the Company's board of directors. Options granted under the 2019 Plan have a term of 10 years (or five years if granted to a 10% stockholder) and generally vest over a 4-year period with 1-year cliff vesting.

As of March 31, 2024, the number of shares available for issuance under the 2019 Plan was 1,638,170.

2015 Equity Incentive Plan

In 2015, the Company established its 2015 Plan which provides for the granting of stock options to employees, directors and consultants of the Company. Options granted under the 2015 Plan may be either ISOs or NSOs.

2019 Employee Stock Purchase Plan

In May 2019, the Company’s board of directors adopted and the Company’s stockholders approved the 2019 Employee Stock Purchase Plan (the “ESPP”). The ESPP provides eligible employees with the opportunity to acquire an ownership interest in the Company through periodic payroll deductions up to 15% of eligible compensation. The offering period is determined by the Company in its discretion but may not exceed 27 months. The per-share purchase price on the applicable exercise date for an offering period is equal to the lesser of 85% of the fair market value of the common stock at either the first business day or last business day of the offering period, provided that no more than 4,000 shares of common stock may be purchased by any one employee during each offering period.

The ESPP is intended to constitute an “employee stock purchase plan” under Section 423(b) of the Internal Revenue Code of 1986, as amended. A total of 195,000 shares of common stock were initially reserved for issuance under the ESPP, subject to an annual increase on January 1 of each year, beginning on January 1, 2020, equal to the lesser of 1% of the shares outstanding on the last day of the immediately preceding fiscal year and such smaller number of shares as may be determined by the Company's board of directors, provided, however, that no more than 2,500,000 shares may be issued under the ESPP.

As of March 31, 2024, the number of shares available for issuance under the ESPP was 1,968,367. For the quarters ended March 31, 2024 and 2023, the Company recorded $0.1 million and $0.2 million, respectively, of compensation expense related to employee participation in the ESPP.

Stock-Based Compensation Expense

Total stock-based compensation expense recorded related to awards granted to employees and non-employees was as follows (in thousands):

	Three Months Ended March 31,
	2024		2023
Research and development	$	3,784	$	2,087
General and administrative		2,528		1,572
Total stock-based compensation expense	$	6,312	$	3,659

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Stock Options

Activity under the Company’s 2015 and 2019 Plans and 2023 Inducement Plan is set forth below:

	Outstanding Options
	Shares			Weighted- Average Exercise Price		Weighted- Average Remaining Contractual Term (Years)		Aggregate Intrinsic Value (Millions)
Balance, January 1, 2024		6,269,975		$	15.53		7.82	$	128.49
Options granted		2,195,438		$	45.91
Options exercised		(464,877	)	$	11.75
Options canceled		(125,612	)	$	19.29
Balance, March 31, 2024		7,874,924		$	24.18		8.36	$	157.56
Exercisable as of March 31, 2024		2,807,378		$	13.34		6.84	$	84.70
Vested and expected to vest as of    March 31, 2024		7,874,924		$	24.18		8.36	$	157.56

The weighted-average grant-date fair value of options granted during the three months ended March 31, 2024 and March 31, 2023 was $33.00 and $12.57 per share, respectively. The aggregate intrinsic value of options exercised for the three months ended March 31, 2024 and March 31, 2023 was $14.5 million and $0.6 million, respectively. Intrinsic values are calculated as the difference between the exercise price of the underlying options and the fair value of the common stock on the date of exercise.

As of March 31, 2024 and December 31, 2023, total unrecognized stock-based compensation expense for stock options was $105.8 million and $41.1 million, respectively, which is expected to be recognized over a weighted-average period of 2.92 years and 2.59 years, respectively.

Black-Scholes Assumptions

The fair values of options were calculated using the assumptions set forth below:

	Three Months Ended March 31,
	2024	2023
Expected term	6.08 years	6.08 years
Expected volatility	80.2% - 81.3%	85.4% - 85.9%
Risk-free interest rate	4.0% - 4.3%	3.6% - 4.1%
Dividend yield	0%	0%

Expected term. The expected term represents the weighted-average period the stock options are expected to remain outstanding and is based on the options’ vesting terms, contractual terms and industry peers, as the Company does not have sufficient historical information to develop reasonable expectations about future exercise patterns and post-vesting employment termination behavior.

Expected Volatility. The expected volatility is based on the Company's historical stock price volatility. The historical stock price volatility is calculated based on a period of time commensurate with the expected term assumption for each grant.

Risk-Free Interest Rate. The risk-free rate assumption is based on U.S. Treasury instruments whose term was consistent with the expected term of the Company’s stock options.

Expected Dividend Rate. The Company has not paid and does not anticipate paying any dividends in the near future. Accordingly, the Company has estimated the dividend yield to be zero.

The Company accounts for forfeitures as they occur.

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Fair Value of Common Stock

The fair value of the Company’s common stock is determined based on the market price on the date of grant.

10. Significant Agreements

GSK Collaboration, Option and License Agreement

In June 2020, the Company entered into the Collaboration, Option and License Agreement (the “GSK Collaboration Agreement”), with an affiliate of GSK plc, GLAXOSMITHKLINE INTELLECTUAL PROPERTY (NO. 4), Limited (“GSK”), pursuant to which the Company and GSK have entered into a collaboration for its synthetic lethality programs targeting MAT2A, Pol Theta and Werner Helicase. On July 27, 2020, ("the Effective Date"), the Company and GSK received Hart-Scott-Rodino Antitrust Improvements Act clearance, or HSR Clearance, and the GSK Collaboration Agreement became effective.

Pursuant to the GSK Collaboration Agreement, GSK paid the Company $100.0 million on July 31, 2020. As of March 31, 2024, GSK has made aggregate payments in the amount of $13.0 million for the achievement of certain development and regulatory milestones with respect to Pol Theta and WRN products.

GSK Collaboration - MAT2A Program

Under the MAT2A program, the Company led research and development through early clinical development stage, and GSK had an exclusive option to obtain an exclusive license to continue development of and commercialize MAT2A products arising out of the MAT2A program, or the Option. The Company delivered an Option data package resulting from its conduct of a dose escalation portion of a MAT2A Phase 1 monotherapy clinical trial pursuant to the GSK Collaboration Agreement, following which the Option was exercisable within a specified time period. In August 2022, the Company received notice from GSK waiving its rights to exercise its Option, or the MAT2A Option Waiver, pursuant to the GSK Collaboration Agreement. As such, the Company retains and fully owns all right, title and interest in and to IDE397 and the MAT2A program, including all worldwide commercial rights thereto. The Company will be responsible for the costs of further research and clinical development activities that the Company conduct for the MAT2A program following the MAT2A Option Waiver.

GSK Collaboration - Pol Theta Program

Pursuant to the GSK Collaboration Agreement, GSK holds a global, exclusive license to develop and commercialize Pol Theta products arising out of the Pol Theta program. The Company and GSK collaborated on preclinical research for the Pol Theta program, and GSK is leading clinical development for the Pol Theta program. GSK is responsible for all research and development costs for the Pol Theta program.

The Company will be eligible to receive total development and regulatory milestones of up to $485.0 million, with respect to each Pol Theta product, including as applicable, for multiple Pol Theta products that target certain alternative protein domains or are based on alternative modalities. Additionally, the Company will be eligible to receive up to $475.0 million of commercial milestones with respect to each Pol Theta product. The Company is also entitled to receive tiered royalties on global net sales of Pol Theta products by GSK, its affiliates and their sublicensees ranging from high single digit to sub-teen double-digit percentages, subject to certain customary reductions.

In June 2022, the Company announced the nomination of a Pol Theta Helicase Inhibitor development candidate, or DC, and in August 2022, announced the achievement of an initial preclinical development milestone in connection with ongoing IND-enabling studies to support evaluation of Pol Theta Helicase Inhibitor DC, triggering a $3.0 million milestone payment, which the Company received in October 2022.

An IND was submitted and was cleared by the FDA in August 2023 to enable clinical evaluation in combination with niraparib, triggering a $7.0 million milestone payment.

The Company has the potential to achieve an additional $10.0 million development milestone upon initiation of Phase 1 clinical dose expansion, as well as potential further aggregate late-stage development and regulatory milestones of up to $465.0 million.

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GSK Collaboration - Werner Helicase Program

Pursuant to the GSK Collaboration Agreement, GSK holds a global, exclusive license to develop and commercialize WRN products arising out of the WRN program. The Company and GSK are collaborating on ongoing preclinical research for the WRN program, and GSK will lead clinical development for the WRN program, with IDEAYA responsible for 20% and GSK responsible for 80% of such global research and development costs. The cost-sharing percentages will be adjusted based on the actual ratio of U.S. to global profits for WRN products, as measured three and six years after global commercial launch thereof.

The Company will be eligible to receive total development milestones of up to $485.0 million, with respect to each WRN product, including as applicable, for multiple WRN products that are based on alternative modalities. Additionally, the Company will be eligible to receive up to $475.0 million of commercial milestones with respect to each WRN product. The Company will be entitled to receive 50% of U.S. net profits and tiered royalties on global non-U.S. net sales of WRN products by GSK, its affiliates and their sublicensees ranging from high single digit to sub-teen double-digit percentages, subject to certain customary reductions. The Company will have a right to opt-out of the 50% U.S. net profit share and corresponding research and development cost share for the WRN program, and would be eligible to receive tiered royalties on U.S. net sales of WRN products by GSK, its affiliates and their sublicensees at the same royalty rates as for global non-U.S. net sales thereafter, with economic adjustments based on the stage of the WRN program at the time of opt-out.

In October 2023, the Company earned a $3.0 million milestone from GSK in connection with IND-enabling studies for the Werner Helicase Inhibitor DC.

GSK Collaboration - General

Under the terms of the GSK Collaboration Agreement, subject to certain exceptions, the Company and GSK will not, directly or through third parties, develop or commercialize other products whose primary and intended mechanism of action is the modulation of WRN or Pol Theta for an agreed upon period of time. The Company and GSK have formed a joint steering committee, joint development committees, and joint commercialization committees responsible for coordinating all activities under the GSK Collaboration Agreement. Ownership of intellectual property developed under the GSK Collaboration Agreement is allocated between or shared by the parties depending on development and subject matter.

GSK’s royalty obligations continue with respect to each country and each product until the later of (i) the date on which such product is no longer covered by certain intellectual property rights in such country and (ii) the 10th anniversary of the first commercial sale of such product in such country.

Each party has the right to sublicense its rights under the GSK Collaboration Agreement subject to certain conditions.

The GSK Collaboration Agreement will continue in effect on a product-by-product and country-by-country basis until the expiration of the obligation to make payments under the GSK Collaboration Agreement with respect to such product in each country, unless earlier terminated by either party pursuant to its terms. Either party may terminate the GSK Collaboration Agreement for the other party’s insolvency or certain uncured breaches. The Company may terminate the GSK Collaboration Agreement if GSK or any of its sublicensees or affiliates challenge certain patents of the Company. GSK may terminate the GSK Collaboration Agreement in its entirety or on a target-by-target basis upon 90-day notice to the Company.

Novartis License Agreement

In September 2018, the Company entered into a license agreement with Novartis to develop and commercialize Novartis’ LXS196 (also known as IDE196), a Phase 1 PKC inhibitor, for the treatment of cancers having GNAQ and GNA11 mutations. The Company renamed Novartis’ LXS196 oncology as IDE196, and which has a non-proprietary name of darovasertib. Under the license agreement, Novartis granted to us a worldwide, exclusive, sublicensable license to research, develop, manufacture, and commercialize certain defined compounds and

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products, including IDE196 and certain other PKC inhibitors as well as companion diagnostic products, collectively referred to as the licensed products, for any purpose.

The Company paid Novartis an upfront payment of $2.5 million and issued 263,615 shares of its Series B redeemable convertible preferred stock concurrently with the execution of the license agreement. Subject to completion of certain clinical and regulatory development milestones, the Company agreed to make milestone payments in the aggregate of up to $9.0 million, and subject to achievement of certain commercial sales milestones, the Company agreed to make milestone payments in the aggregate of up to $20.0 million. The Company also agreed to pay mid to high single-digit tiered royalty payments based on annual worldwide net sales of licensed products, payable on a licensed product-by-licensed product and country by country basis until the latest of the expiration of the last to expire exclusively licensed patent, the expiration of regulatory exclusivity, and the ten year anniversary of the first commercial sale of such product in such country. The royalty payments are subject to reductions for lack of patent coverage, loss of market exclusivity, and payment obligations for third-party licenses.

Pfizer Clinical Trial Collaboration and Supply Agreements

In March 2020, the Company entered into a clinical trial collaboration and supply agreement with Pfizer, Inc., or the Pfizer Agreement, as amended in September 2020, April 2021, September 2021 and May 2023. Pursuant to the Pfizer Agreement, Pfizer supplies the Company with their MEK inhibitor, binimetinib, and their cMET inhibitor, crizotinib, to evaluate combinations of darovasertib independently with each of the Pfizer compounds, in patients with tumors harboring activating GNAQ or GNA11 mutations. Under the Pfizer Agreement, the Company is the sponsor of the combination studies and will provide darovasertib and pay for the costs of the combination studies. Pfizer will provide binimetinib and crizotinib for use in the clinical trial at no cost to the Company. The Pfizer Agreement provides that the Company and Pfizer will jointly own clinical data generated from the clinical trial and will also jointly own inventions, if any, relating to the combined use of darovasertib and binimetinib, or independently, to the combined use of darovasertib and crizotinib. The Company and Pfizer have formed a joint development committee responsible for coordinating all regulatory and other activities under the agreement.

In March 2022, the Company and Pfizer entered into a second clinical trial collaboration and supply agreement, or the Second Pfizer Agreement, pursuant to which the Company is evaluating darovasertib and crizotinib as a combination therapy in MUM in a planned Phase 2/3 potential registration-enabling clinical trial. Pursuant to the Second Pfizer Agreement, the Company is the sponsor of the combination trial and the Company will provide darovasertib and pay for the costs of the combination trial; Pfizer will provide crizotinib for the planned combination trial at no cost to us for up to an agreed-upon number of MUM patients. The Company and Pfizer will jointly own clinical data from the planned combination trial and all inventions relating to the combined use of darovasertib and crizotinib. The Company and Pfizer have formed a joint development committee responsible for coordinating all regulatory and other activities under the Second Pfizer Agreement.

Separately, in March 2022, the Company and Pfizer also entered into a third clinical trial collaboration and supply agreement, or the Third Pfizer Agreement, pursuant to which the Company may, subject to preclinical validation and FDA feedback and guidance, evaluate darovasertib and crizotinib, as a combination therapy in cMET-driven tumors such as NSCLC and/or HCC in a Phase 1 clinical trial. Pursuant to the Third Pfizer Agreement, the Company is the sponsor of the planned combination trial, and the Company will provide darovasertib and pay for the costs of the combination trial; Pfizer will provide crizotinib for the planned combination trial at no cost to us.

In May 2023, the Company continued our relationship with Pfizer by entering into Amendment No. 4 to the Pfizer Agreement relating to the supply of crizotinib in support of this Phase 2 clinical trial, pursuant to which Pfizer will continue to provide us with an additional defined quantity of crizotinib at no cost.

The Company also expanded its relationship with Pfizer in May 2023 under an Amendment No. 1 to the Second Pfizer Agreement to support the Phase 2/3 registrational trial to evaluate darovasertib and crizotinib as a combination therapy in MUM. Under the as-amended Second Pfizer Agreement, Pfizer will provide the Company with a first defined quantity of crizotinib at no cost, as well as an additional second defined quantity of crizotinib at a lump-sum cost. Under Amendment No. 1 to the Second Pfizer Agreement, the Company and Pfizer also terminated the Third Pfizer Agreement.

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Cancer Research UK and University of Manchester Exclusive Option and License Agreement

In January 2022, the Company exercised its option for an exclusive worldwide license covering a broad class of PARG inhibitors from Cancer Research Technology Ltd. and the University of Manchester, and in connection therewith, paid a one-time option exercise fee of £250,000. The Company will be obligated to make payments to CRT aggregating up to a total of £19.5 million upon the achievement of specific development and regulatory approval events for development of a PARG inhibitor in oncologic diseases. The Company will also pay low single-digit tiered royalties, and potentially also sales-based milestones, to CRT based on net sales of licensed products. In addition, in the event the Company sublicenses the intellectual property, it will also be obligated to pay CRT a specified percentage of any sublicense revenue.

In April 2023, the Company incurred an obligation to pay milestone payments in an aggregate amount of £750,000 to CRT based upon the achievement of certain milestones relating to first and second tumor histologies in connection with the Phase 1 portion of the Phase 1/2 clinical trial in oncologic diseases.

The Company will be obligated to make additional payments to CRT aggregating up to £18.75 million upon the achievement of specific development and regulatory approval events for development of a PARG inhibitor in oncologic diseases, including an aggregate of up to £1.5 million and up to £2.25 for the achievement of certain Phase 2 and Phase 3 development milestones, respectively, in each case as relating to first and second tumor histologies.

Amgen Clinical Trial Collaboration and Supply Agreement

In July 2022, the Company entered into a clinical trial collaboration and supply agreement with Amgen Inc., or the Amgen CTCSA, to clinically evaluate IDE397 in combination with AMG 193, the Amgen investigational MTA-cooperative PRMT5 inhibitor, in patients having MTAP-null solid tumors, in a Phase 1/2 clinical trial. Under the mutually non-exclusive Amgen CTCSA, the Company will provide IDE397 drug supply to Amgen, who will be the sponsor of the Phase 1 clinical combination trial evaluating IDE397 and AMG 193. Each party will pay for fifty percent (50%) of the external third-party costs of the combination study. Each party will be responsible for its own internal costs and expenses in support of the combination study. The Company and Amgen will jointly oversee clinical development of the combination therapy through a Joint Oversight Committee responsible for coordinating all regulatory and other activities under the Amgen CTCSA. The parties will jointly own collaboration data and combination-related intellectual property, if any, arising from the combination clinical trial. The Company and Amgen each retain commercial rights to its respective compounds, including with respect to use as a monotherapy agent or combination agent.

Gilead Clinical Study Collaboration and Supply Agreement

In November 2023, the Company entered into a clinical study collaboration and supply agreement with Gilead Sciences, Inc., or the Gilead CSCSA, to clinically evaluate IDE397 in combination with Trodelvy (sacituzumab-govitecan-hziy), a Trop-2 directed ADC, in patients having MTAP-deletion bladder cancer, in a Phase 1 clinical trial. Under the mutually non-exclusive Gilead CSCSA, the Company will receive Trodelvy drug supply from Gilead and will sponsor the Phase 1 clinical combination trial evaluating ID397 and Trodelvy. Gilead will bear internal or external costs incurred in connection with its supply of Trodelvy. The Company will bear all internal and external costs and expenses associated with the conduct of the combination study. The Company and Gilead will jointly oversee clinical development of the combination therapy through a Joint Steering Committee responsible for coordinating all regulatory and other activities under the Gilead CSCSA. The Company and Gilead each retain commercial rights to its respective compounds, including with respect to use as a monotherapy agent or combination agent.

Merck Clinical Trial Collaboration and Supply Agreement

In March 2024, the Company entered Clinical Trial Collaboration and Supply Agreement, or the Merck CTCSA, with MSD International Business GmbH, a subsidiary of Merck & Co., Inc., Rahway, NJ, USA, or Merck. The Company is planning to evaluate IDE161 in a combination study with KEYTRUDA® (pembrolizumab), Merck's

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anti-PD-1 therapy, in patients with MSI-high and MSS endometrial cancer. Pursuant to the Merck CTCSA, the Company is the sponsor of the combination study and the Company will provide the IDE161 compound and pay for the costs of the combination study. Merck will provide KEYTRUDA at no cost to the Company. The Company and Merck will jointly own clinical data from the combination. Each party retains commercial rights to its respective compounds, including with respect to use as a monotherapy or combination agent.

11. Revenue Recognition

The Company recognizes revenue in accordance with ASC 606 for the GSK Collaboration Agreement (see Note 10, Significant Agreements).

Disaggregation of Revenue

The Company recognized no revenue for the quarter ended March 31, 2024 and $7.9 million for the quarter ended March 31, 2023. The $7.9 million revenue for the quarter ended March 31, 2023 consisted of $7.6 million, $0.2 million, and $0.1 million related to the WRN, MAT2A & Pol Theta programs, respectively. The Company completed all performance obligations related to the upfront payment under the GSK Collaboration Agreement as of December 31, 2023. Future collaboration revenue recognized under the GSK Collaboration Agreement will be related to future milestone payments as they are earned.

Contract Balances

As of March 31, 2024 and December 31, 2023, the Company had no accounts receivable and no contract liabilities related to the GSK Collaboration Agreement.

The Company has identified the following six performance obligations associated with the GSK Collaboration Agreement:

(i)Preclinical and Phase 1 Monotherapy clinical research and development services under the MAT2A program (“MAT2A R&D Services”)

(ii)Preclinical research services and the related license to IDEAYA-owned technology under the Pol Theta program (“Pol Theta R&D Services”)

(iii)Preclinical research services and the related license to IDEAYA-owned technology under the WRN program (“WRN R&D Services”)

(iv)Material right associated with the option to license IDEAYA-owned technology under the MAT2A program (“Option”)

(v)Material right associated with the option to license to IDEAYA-owned technology under the MAT2A program to the extent necessary for preclinical activities in preparation for the MAT2A Combination Trial (“Preclinical MAT2A License”)

(vi)Material right associated with the supply of MAT2A product for the MAT2A Combination Trial (“MAT2A Supply”)

The Company recognizes revenue related to amounts allocated to the MAT2A R&D services as the underlying services are performed over the period through the delivery of the Option data package, which is generated from its conduct of the dose escalation portion of the MAT2A Phase 1 monotherapy clinical trial. The Company uses its internal research and development capability and also engages third-party clinical research organizations, or CROs, for which the Company acts as a principal. The Company has delivered the Option data package to GSK. Accordingly, the performance obligation related to the MAT2A R&D services has been fulfilled.

With respect to the Pol Theta and WRN programs, the Company identified two promises: (1) granting of the license to develop and commercialize Pol Theta and WRN products, respectively, and (2) the preclinical research services. The Company has determined that these two promises are not distinct within the context of the contract.

For the Pol Theta product, the Company achieved and earned a $7.0 million payment for a milestone in August 2023 based on acceptance of the IND by the FDA, payment. An earlier preclinical development $3.0 million milestone

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payment from GSK was achieved in August 2022 in connection with ongoing IND-enabling studies to support evaluation of GSK101. The Company has the potential to receive an additional $10.0 million milestone payment upon initiation of Phase 1 clinical dose expansion.

For the WRN product, the Company achieved and earned a $3.0 million payment for a milestone in October 2023 in connection with IND-enabling studies for the Werner Helicase Inhibitor DC. The Company is, in collaboration with GSK, targeting an IND submission in 2024 to enable first-in-human clinical evaluation of its Werner Helicase Inhibitor DC in high MSI tumors.

The Company recognized revenue related to amounts allocated to the Pol Theta R&D Services and WRN R&D Services as the underlying services are performed over the period through the completion of the Pol Theta and WRN preclinical research programs, respectively. Within 90 days from the end of each calendar quarter, GSK reimbursed the Pol Theta program costs incurred by the Company. Within 75 days from the end of each calendar quarter, the Company and GSK determined the amounts of WRN program costs incurred by both parties and the net amount owed by GSK to the Company or by the Company to GSK, which was paid within 75 days from such determination by a reimbursing party. The Company used its internal research capability and may also engage third-party clinical research organizations, or CROs, in transferring the Pol Theta R&D services and WRN R&D services, for which the Company acts as a principal. The Company completed Pol Theta R&D services during December 2022. Accordingly, the performance obligation related to the Pol Theta R&D services has been fulfilled. The Company completed WRN R&D services during December 2023. Accordingly, the performance obligation related to the WRN R&D services has been fulfilled.

As of March 31, 2024, there are no remaining performance obligations related to the WRN, Pol Theta and MAT2A program.

Significant judgments

In applying ASC 606 to the GSK Collaboration Agreement, the Company made the following judgments that significantly affect the timing and amount of revenue recognition:

(i) Determination of the transaction price, including whether any variable consideration is included at inception of the contract

The transaction price is the amount of consideration that the Company expects to be entitled to in exchange for transferring promised goods or services to the customer. The transaction price must be determined at inception of a contract and may include amounts of variable consideration. However, there is a constraint on inclusion of variable consideration in the transaction price, if there is uncertainty at inception of the contract as to whether such consideration will be recognized in the future.

The decision as to whether or not it is probable that a significant reversal of revenue will occur in the future, depends on the likelihood and magnitude of the reversal and is highly susceptible to factors outside the Company’s influence (for example, the Company cannot determine the outcome of clinical trials; the Company cannot determine if or when the counterparty will initiate or complete clinical trials; and the Company cannot determine if or when an regulatory agency provides any approval). In addition, the uncertainty is not expected to be resolved for a long period and finally, the Company has limited experience in the field. Therefore, at inception of the GSK Collaboration Agreement, development and regulatory milestones were fully constrained and were not included in the transaction price based on the factors noted above.

The Company constrains estimates of other variable consideration, such as reimbursable program costs, to amounts that are not expected to result in a significant revenue reversal in the future. The Company re-evaluates the transaction price, including the estimated variable consideration included in the transaction price and all constrained amounts, in each reporting period and as uncertain events are resolved or other changes in circumstances occur.

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12. Net Loss Per Share Attributable to Common Stockholders

The following table sets forth the computation of basic and diluted net loss per share attributable to common stockholders (in thousands, except share and per share data):

	Three Months Ended March 31,
	2024			2023
Numerator:
Net loss attributable to common stockholders	$	(39,572	)	$	(23,640	)
Denominator:
Weighted-average common shares outstanding, basic and diluted(1)		75,108,484			48,370,074
Net loss per share attributable to common stockholders, basic and diluted	$	(0.53	)	$	(0.49	)

(1) The shares underlying the pre-funded warrants to purchase shares of the Company's common stock have been included in the calculation of the weighted-average number of shares outstanding, basic and diluted, for the three months ended March 31, 2024.

The following outstanding shares of potentially dilutive securities were excluded from the computation of diluted net loss per share attributable to common stockholders for the periods presented because including them would have been antidilutive:

	As of March 31,
	2024	2023
Options to purchase common stock	7,874,924	6,874,959
Total	7,874,924	6,874,959

13. Subsequent Events

Subsequent to March 31, 2024, from April 1, 2024 through April 24, 2024, the Company sold an aggregate of 922,000 shares of common stock for aggregate gross proceeds of $37.2 million at a weighted average sales price of approximately $40.40 per share under the at-the-market offering pursuant to the January 2024 Sales Agreement with Jefferies as sales agent, generating net proceeds of approximately $36.5 million, after deducting underwriting discounts and commissions and other estimated offering expense. As of April 24, 2024, approximately $182.1 million of common stock remained available to be sold under the ATM facility.

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Item 2. Management’s Discussion and Analysis of Financial Condition and Results of Operations.

The following discussion and analysis of our financial condition and results of operations should be read in conjunction with our financial statements and related notes appearing elsewhere in this Quarterly Report on Form 10-Q. Some of the information contained in this discussion and analysis or set forth elsewhere in this Quarterly Report on Form 10-Q, including information with respect to our plans and strategy for our business, includes forward-looking statements that involve risks and uncertainties. As a result of many factors, including those factors set forth in the “Risk Factors” section of this Quarterly Report on Form 10-Q, our actual results could differ materially from the results described, in or implied, by these forward-looking statements. Please also see the section of this Quarterly Report on Form 10-Q titled “Forward-Looking Statements.”

Overview

We are a precision medicine oncology company committed to the discovery and development of targeted therapeutics for patient populations selected using molecular diagnostics. Our approach integrates small molecule drug discovery with extensive capabilities in identifying and validating translational biomarkers to develop targeted therapies for select patient populations that are most likely to benefit from these targeted therapies. Our small molecule drug discovery expertise includes discovery and development of small molecule therapeutics. We are applying these capabilities to develop a robust pipeline in precision medicine oncology.

Our clinical pipeline includes four potential first-in-class clinical-stage product candidates – darovasertib (PKC), IDE397 (MAT2A), IDE161 (PARG) and GSK101 (Pol Theta Helicase). We own or control all commercial rights of the three most-advanced of these product candidates: darovasertib, IDE397, and IDE161. We are also advancing our Werner Helicase program for which a development candidate has been selected in collaboration with GlaxoSmithKline, or GSK and, subject to investigational new drug-, or IND-, enabling studies, are targeting an IND in 2024. We also have multiple earlier-stage preclinical programs. We have established selective, value-accretive collaborations with leading pharmaceutical companies to support our clinical development activities.

Darovasertib – PKC Inhibitor Clinical Candidate in Uveal Melanoma and GNAQ/11 Melanomas

Darovasertib (IDE196) is our most advanced clinical-stage product candidate, which we in-licensed from Novartis. Darovasertib is a potent, selective small molecule inhibitor of protein kinase C, or PKC, which we are developing for genetically-defined cancers having GNAQ or GNA11 gene mutations. PKC is a protein kinase that functions downstream of the GTPases GNAQ and GNA11.

We have achieved double-digit patient enrollment and have opened multiple clinical sites, including international sites, in our potential registration-enabling Phase 2/3 clinical trial, designated as IDE196-002. The purpose of the clinical trial is to evaluate darovasertib in combination with crizotinib, Pfizer’s investigational cMET inhibitor, in patients having metastatic uveal melanoma, or MUM, with human leukocyte antigen-, or HLA-A*02:01 negative, or HLA-A2(-), serotype, as part of a second Clinical Trial Collaboration and Supply Agreement, or Second Pfizer agreement, with Pfizer. We are targeting clinical program update(s) in 2024.

We are planning to enroll additional HLA-A*02:01 positive, or HLA-A2(+), patients as an independent clinical strategy to address HLA-A2(+) MUM patients, in our ongoing Phase 2 clinical trial, designated as IDE196-001. We are further evaluating darovasertib in combination with crizotinib in the Phase 2 expansion arm of IDE196-001 in patients with GNAQ/11 melanomas, including metastatic cutaneous melanoma.

We separately initiated and have achieved double-digit patient enrollment in our Phase 2 clinical trial, designated as IDE196-009, evaluating darovasertib as single-agent neoadjuvant and adjuvant therapy in patients having primary uveal melanoma, or UM, with ongoing enrollment and multiple clinical sites open. A clinical efficacy update on over 30 patients and an U.S. Food and Drug Administration, or FDA, regulatory guidance update are both targeted in the second half of 2024.

We are also supporting evaluation of darovasertib as single-agent neoadjuvant and adjuvant therapy in primary UM in an ongoing investigator-sponsored clinical trial, or IST, captioned as “Neoadjuvant / Adjuvant trial of Darovasertib in Ocular Melanoma”, or NADOM, led by St. Vincent’s Hospital in Sydney with the participation of Alfred Health and the Royal Victorian Eye and Ear Hospital in Melbourne. The interim results from the trial have

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been accepted for an oral presentation at the upcoming 2024 American Society of Clinical Oncology, or ASCO, annual meeting in June 2024.

We are pursuing a clinical strategy for darovasertib to broadly address uveal melanoma, alternatively referred to as ocular melanoma, in both primary and metastatic settings. Greater than 90% of uveal melanoma patients have tumors harboring GNAQ or GNA11 mutations. There are no FDA approved systemic therapies for primary UM, as either neoadjuvant or adjuvant therapies. There are likewise no FDA approved therapies for patients having MUM with HLA-A*02:01 negative, or HLA-A2(-), serotype. These primary UM patients and HLA-A2(-) MUM patients collectively represent approximately 85% of all ocular melanoma patients. We have a separate, independent clinical strategy to address HLA-A*02:01 positive, or HLA-A2(+), MUM patients.

The potentially addressable patient population for MUM is estimated to include an annual incidence of approximately 4,500 patients across the United States, or U.S., and Europe, with an estimated total prevalence of approximately 14,000 patients in the U.S. and Europe. (Neo)Adjuvant UM represents a significant expansion opportunity for darovasertib – with a potential annual incidence of approximately 8,700 patients aggregate in U.S. and Europe and with an estimated total prevalence of approximately 100,000 patients in the U.S. and Europe.

We own or control all commercial rights in our darovasertib program in uveal melanoma, including in MUM and in primary UM, subject to certain economic obligations pursuant to our exclusive, worldwide license to darovasertib with Novartis.

Darovasertib – Potential Registration-Enabling Clinical Trial in First-Line HLA-A2(-) MUM

The protocol of the Phase 2/3 clinical trial design incorporates guidance and feedback following our Type C meeting with the FDA in March 2023. This protocol includes an integrated Phase 2/3 open-label study-in-study design in first-line MUM patients with an HLA-A2(-) serotype. The clinical trial design employs a Phase 2 portion with median progression free survival, or PFS, as a primary endpoint for potential accelerated approval. Patients enrolled in Phase 2 will continue on treatment within the same study and will be considered, together with additional enrolled patients, to evaluate overall survival, or OS, as the primary endpoint of the Phase 3 portion of the clinical trial to support a potential confirmational approval.

In the Phase 2 portion of the clinical trial, approximately 230 patients will be randomized on a 2:1 basis for treatment with the darovasertib and crizotinib combination in the treatment arm or investigators choice in the control arm, selected from (a) a combination of ipilimumab (ipi) and nivolumab (nivo), (b) PD1-targeted monotherapy or (c) dacarbazine. The treatment arm of the Phase 2 portion of the clinical trial includes a nested study to confirm the move forward combination dose for the integrated Phase 2/3 clinical trial – including cohorts at the Phase 2 expansion doses of (i) darovasertib 300 mg BID + crizotinib 200 mg BID and (ii) darovasertib 200 mg BID + crizotinib 200 mg BID. Under the nested study design, patients enrolled in the cohort at the move forward dose will be included within the Phase 2/3 registrational clinical trial. The Phase 2 portion of the clinical trial contemplates an efficacy and safety data set of approximately 200 patients randomized 2:1 with the treatment arm at the move forward dose to support a potential accelerated approval based on median PFS by blinded independent central review, or BICR, as a primary endpoint. Accelerated approval is intended to allow for earlier approval of drugs that treat serious conditions and fill an unmet medical need based on a demonstration of effectiveness on a surrogate endpoint.

Patients enrolled in Phase 2 at the selected dose would continue on treatment and be included in the Phase 3 study analysis, supplemented by enrollment of approximately 120 additional patients into the Phase 3 portion of the clinical trial, with 2:1 randomization on the same basis as the Phase 2 portion. Efficacy data from the Phase 3 could support potential approval using median OS as a primary endpoint.

In May 2023, we expanded our relationship with Pfizer to support the Phase 2/3 registrational trial to evaluate darovasertib and crizotinib as a combination therapy in MUM by entering into Amendment No. 1 to the Second Pfizer Agreement. Under the as-amended Second Pfizer Agreement, Pfizer will provide us with a first defined quantity of crizotinib at no cost, as well as an additional second defined quantity of crizotinib at a lump-sum cost. We anticipate that the supply of crizotinib under the Second Pfizer Agreement, as amended, will be sufficient to support the planned Phase 2 and Phase 3 portions of the Phase 2/3 potentially registrational clinical trial.

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In parallel, we are continuing to evaluate darovasertib in our ongoing Phase 2 clinical trial, designated as IDE196-001, as a combination therapy with crizotinib in MUM patients. We are the sponsor of this Phase 2 clinical trial and are collaborating with Pfizer on this Phase 2 clinical trial pursuant to the Pfizer Agreement.

Prevalence of HLA-A2*02:01 Negative Serotype in MUM

Data from darovasertib clinical trials in MUM demonstrate that approximately 70% of MUM patients with known HLA-A*02:01, or HLA-A2 status were HLA-A2(-). As reported at ESMO 2023, the HLA-A2 status was known in subsets of patients enrolled in clinical trials evaluating darovasertib. Prevalence of HLA-A2(+) and HLA-A2(-) in MUM patients was determined from a first data set of n=149 MUM patients treated with darovasertib as monotherapy or in a combination arm of a clinical trial, and separately in a second data set of n=118 MUM patients treated with the darovasertib and crizotinib combination. These data include 102 of 149 (68%) of patients in the all-treatment subset and 81 of 118 (69%) patients in the darovasertib and crizotinib combination treatment subset.

Darovasertib – Strategy for HLA-A*02:01 Positive MUM

Based on clinical data from the Phase 2 clinical trial evaluating darovasertib and crizotinib in MUM as reported at ESMO 2023, and based on the darovasertib mechanism of action, we anticipate darovasertib will have clinical activity independent of HLA-A2 status in GNAQ/11-mutation cancers.

We are planning to enroll additional HLA-A*02:01 positive, or HLA-A2(+), patients as an independent clinical strategy to address HLA-A2(+) MUM patients, in our ongoing Phase 2 clinical trial, designated as IDE196-001. This strategy demonstrates our commitment to fully address the high unmet medical need in MUM. Such clinical trial data from darovasertib and crizotinib combination treatment in HLA-A2(+) MUM could support publication and potential inclusion in NCCN Clinical Practice Guidelines in Oncology.

Darovasertib – Orphan Drug Designation in UM and Fast Track Designation in MUM

In April 2022, the FDA designated darovasertib as an Orphan Drug in UM, including primary and metastatic disease under 21 C.F.R Part 316. Under an Orphan Drug designation, darovasertib may be entitled to certain tax credits for qualifying clinical trial expenses, exemption from certain user fees and, subject to FDA approval of a New Drug Application, or NDA, for darovasertib in UM, eligibility for seven years of statutory marketing exclusivity. As an FDA-designated Orphan Drug, darovasertib may also be excluded from certain mandatory price negotiation provisions of the 2022 Inflation Reduction Act, if approved.

In November 2022, the FDA granted Fast Track designation to our development program investigating darovasertib in combination with crizotinib in adult patients being treated for MUM. The Fast Track designation makes our darovasertib and crizotinib development program eligible for various expedited regulatory review processes, including generally more frequent FDA interactions, such as meetings and written communications, potential eligibility for rolling review of a future NDA and potential accelerated approval and priority review of an NDA.

Darovasertib - Neoadjuvant and Adjuvant Therapy in Uveal Melanoma (UM)

We are clinically evaluating the potential for darovasertib as neoadjuvant or adjuvant therapy, or both, also referred to as (neo)adjuvant therapy, in primary, non-metastatic UM patients. We previously reported preliminary clinical data in the neoadjuvant setting showing evidence of anti-tumor activity that we believe supports further clinical evaluation of darovasertib to determine its potential as a neoadjuvant therapy to either save the eye by avoiding enucleation, or to reduce the tumor thickness in the eye, enabling treatment with less radiation to preserve vision, and as an adjuvant therapy, to potentially extend relapse free survival.

We have initiated and achieved double-digit patient enrollment in our company-sponsored Phase 2 clinical trial designated as IDE196-009, with ongoing enrollment and multiple clinical sites open. The purpose of the clinical trial is to evaluate single-agent darovasertib as neoadjuvant treatment of primary UM prior to primary interventional treatment of enucleation or radiation therapy and also as adjuvant therapy following the primary treatment. A

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clinical efficacy update on over 30 patients and an FDA regulatory guidance update are both targeted in the second half of 2024.

The IDE196-009 clinical protocol includes neoadjuvant treatment with darovasertib to maximum benefit up to 6 months, primary treatment, then up to 6 months of follow-up adjuvant therapy.

In the neoadjuvant setting, one cohort of UM patients with large tumors will be treated with darovasertib until maximum benefit or six months, at which time they will undergo a primary interventional treatment. The neoadjuvant endpoint for this large-sized tumor cohort is eye preservation. For example, a patient who would otherwise have undergone enucleation would instead be eligible for radiation treatment. Another neoadjuvant cohort of UM patients with small or medium sized tumors will be treated with darovasertib until maximum benefit or six months, at which time they will undergo radiation therapy. Neoadjuvant endpoints for this small- or medium-sized tumor cohort include (i) reducing the radiation dose that the patient receives, relative to the radiation dose they would have otherwise received without the neoadjuvant treatment, and (ii) functional vision preservation.

In the adjuvant setting, each of the two neoadjuvant cohorts will be treated with darovasertib for up to six months as follow-up adjuvant therapy after the primary interventional treatment. The adjuvant endpoints for this portion of the clinical trial include relapse free survival and useful vision.

We are additionally supporting evaluation of darovasertib as (neo)adjuvant therapy in primary UM in the ongoing NADOM IST. Pursuant to an as-amended protocol for the NADOM study, uveal melanoma patients who would otherwise undergo enucleation are instead treated with single agent darovasertib as neoadjuvant treatment for up to six months or maximum benefit. This reflects an increase in potential treatment duration versus the initial approach of one month neoadjuvant therapy, following which these patients will undergo a primary interventional treatment. Patients will subsequently be treated with darovasertib for up to six months as follow-up adjuvant therapy after the primary interventional treatment. The topline results from the trial have been accepted for an oral presentation at the upcoming 2024 ASCO annual meeting.

Darovasertib – Expansion Opportunity in GNAQ/11 Melanomas

We have initiated a Phase 2 expansion arm in our IDE196-001 clinical trial evaluating the darovasertib and crizotinib combination in GNAQ/11 melanomas, including metastatic cutaneous melanoma, based on observed preliminary clinical efficacy. There are currently no FDA approved therapies in this indication in this genetically-defined patient population.

The GNAQ/11 prevalence in cutaneous melanoma has been reported at approximately 5% in The Cancer Genome Atlas. The GNAQ/11 cutaneous melanoma estimated annual incidence is approximately 5,000 patients in the United States and 8,000 patients in the EU28, and the estimated total prevalence of GNAQ/11 cutaneous melanoma is approximately 70,000 patients in the United States and 110,000 patients in the EU28. It has been reported that approximately 12.5% to 15% of cutaneous melanoma patients have been reported to develop metastatic disease.

IDE397 – MAT2A Inhibitor in Tumors with MTAP Deletion

IDE397 is a clinical-stage, potent, selective small molecule inhibitor of methionine adenosyltransferase 2a, or MAT2A, which we are developing for patients having solid tumors with MTAP deletion. The prevalence of methylthioadenosine phosphorylase, or MTAP, gene deletion is estimated to be approximately 15% of human solid tumors. MTAP deletion in patient tumors is identified by commercial or institutional next generation sequencing, or NGS, panels or by MTAP immunohistochemistry, or IHC, assay with confirmation by NGS.

MTAP-null cells lack the ability to metabolize 5-methylthioadenosine, or MTA, which is an essential step in a biochemical pathway involved in salvaging the metabolite S-adenosyl methionine, or SAM. Increased levels of MTA partially inhibit the methyltransferase PRMT5 for which SAM is the methyl-donor substrate for methylation of various proteins. This partial inhibition of PRMT5 by increased levels of MTA renders MTAP-null cells more dependent on the activity of MAT2A, an enzyme that is responsible for the synthesis of SAM. Because of this enhanced dependence, loss of MTAP results in synthetic lethality when MAT2A is pharmacologically inhibited.

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We are enrolling patients into a Phase 2 clinical trial designated as IDE397-001 to evaluate IDE397 for patients having certain tumors with MTAP gene deletion. We are proceeding with enrollment of MTAP-deletion patients into a monotherapy Phase 2 expansion cohort with an initial focus on high priority solid tumor types, including non-small cell lung cancer, or NSCLC, and bladder cancers. We have selected a move-forward Phase 2 expansion dose for IDE397 monotherapy in MTAP-deletion squamous NSCLC, based on adverse event profile and preliminary clinical efficacy observed, including multiple partial responses by RECIST 1.1. MTAP-deletion squamous NSCLC is estimated to have a global annual incidence greater than 100,000 patients. In addition, multiple partial responses by RECIST 1.1 have also been observed in MTAP-deletion bladder cancer with IDE397 monotherapy and evaluation is ongoing for further potential Phase 2 expansion in this tumor type.

We are collaborating with Amgen to clinically evaluate IDE397 in combination with AMG 193, the Amgen investigational MTA-cooperative PRMT5 inhibitor, in patients having tumors with MTAP deletion, in an Amgen-sponsored clinical trial pursuant to our Clinical Trial Collaboration and Supply Agreement with Amgen, or the Amgen CTCSA.

The combination of IDE397 with AMG 193 is a novel and potential first-in-class synthetic lethality combination which targets two distinct and mechanistically complementary nodes of the MTAP methylation pathway – MAT2A and PRMT5, providing a complementary approach for targeting MTAP-null tumors.

In August 2023, Amgen initiated and dosed a first patient in the IDE397 /AMG 193 combination study, following FDA authorization to proceed with the clinical trial. This Phase 1/2 clinical trial (NCT: 05975073) will evaluate the safety, tolerability, pharmacokinetics, pharmacodynamics and efficacy of IDE397 in combination with AMG 193, with an initial focus for expansion in NSCLC patients and an estimated enrollment of approximately 180 patients. Enrollment is ongoing in the dose escalation portion of this Phase 1/2 clinical trial. We are targeting the development of a joint publication strategy in 2024.

We are separately collaborating with Gilead to clinically evaluate IDE397 in combination with sacituzumab-govitecan-hziy, or Trodelvy, Gilead’s Trop-2 directed anti-body conjugate, or ADC, in patients having MTAP deletion bladder cancer, in the Phase 1 IDEAYA-sponsored clinical trial pursuant to a Clinical Study Collaboration and Supply Agreement, or Gilead CSCSA, with Gilead Sciences, Inc., or Gilead. Trial initiation activities for the IDE397 and Trodelvy clinical combination are ongoing and the dosing of a first patient is anticipated in mid-year, or the second or third quarters of, 2024.

We own all rights, title, and interest in and to IDE397 and the MAT2A program, including all worldwide commercial rights thereto.

IDE161 – PARG Inhibitor in Tumors with Homologous Recombination Deficiency

We are evaluating IDE161, a small molecule inhibitor of poly (ADP-ribose) glycohydrolase, or PARG, being evaluated in a Phase 1/2 clinical trial designated as IDE161-001 for patients having tumors with homologous recombination deficiency, or HRD, and potentially other genetic and/or molecular signatures. PARG is a novel target in a clinically validated biological pathway. PARG functions as a regulator of DNA repair in the same biochemical pathway as poly-(ADP-ribose) polymerase, or PARP. PARG hydrolyzes poly (ADP-ribose), or PAR, chains that are polymerized by PARP enzymes, completing the PAR cycle. Small molecule inhibitors of PARG result in a dose dependent increase in cellular PAR after DNA damage. PARG is a mechanistically distinct target relative to PARP.

We are progressing with enrollment of patients having tumors with HRD into the Phase 1 expansion portion of the Phase 1/2 clinical trial in selected priority tumors. In parallel, we are also continuing with Phase 1 dose optimization to confirm a move-forward expansion dose for the planned Phase 2 portion of the clinical trial. We are targeting an initial Phase 2 monotherapy expansion in HRD solid tumors in the second half of 2024. We are also validating IDE161 combination opportunities preclinically and targeting identification of potential combination(s) in 2024.

The expansion portion of the Phase 1 trial has a strategic focus in estrogen receptor positive, or ER+, human epidermal growth factor receptor 2 negative, or Her2(-), breast cancer with HRD, as well as other solid tumors with

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HRD, such as endometrial cancer, colorectal cancer and prostate cancer. The ER+, Her2-, HRD+ breast cancer focus represents approximately 10% to 14% of breast cancer patients.

In September 2023, we received Fast Track Designation from the FDA for IDE161 for ovarian cancer and breast cancer indications. Specifically, for IDE161, Fast Track Designation was received for the treatment of adult patients having advanced or metastatic ovarian cancer with germline or somatic BRCA 1/2 mutations who are platinum resistant and have received prior antiangiogenic and PARP inhibitor therapies. The Fast Track Designation was also received for IDE161 for the treatment of adult patients having advanced or metastatic HR+, Her2- breast cancer with germline or somatic BRCA 1/2 mutations who have progressed following treatment with at least one line of a hormonal therapy, a CDK4/6 inhibitor therapy and a PARP inhibitor therapy.

We entered into an exclusive license under the Evaluation, Option and License Agreement, by and among the Company, Cancer Research Technologies Ltd., also known as Cancer Research United Kingdom, or CRT, and the University of Manchester, pursuant to which we hold exclusive worldwide license rights covering a broad class of PARG inhibitors.

In April 2023, we incurred an obligation to pay milestone payments in an aggregate amount of £750,000 to CRT based upon the achievement of certain milestones relating to first and second tumor histologies in connection with the Phase 1 portion of the IDE161-001 Phase 1/2 clinical trial in oncologic diseases. We will be obligated to make additional payments to CRT aggregating up to £18.75 million upon the achievement of specific development and regulatory approval events for development of a PARG inhibitor in oncologic diseases, including an aggregate of up to £1.5 million and up to £2.25 for the achievement of certain Phase 2 and Phase 3 development milestones, respectively, in each case as relating to first and second tumor histologies.

In March 2024, we entered into the Clinical Trial Collaboration and Supply Agreement, or Merck CTCSA, with MSD International Business GmbH, a subsidiary of Merck & Co., Inc., Rahway, NJ, USA. We are planning to evaluate IDE161 in a combination study with KEYTRUDA® (pembrolizumab), Merck's anti-PD-1 therapy, in patients with high microsatellite instability, or MSI, and microsatellite stable, or MSS, endometrial cancer. We are targeting a first-patient dosing for this study in the second half of 2024.

KEYTRUDA® is a registered trademark of Merck Sharp & Dohme LLC, a subsidiary of Merck & Co., Inc., Rahway, NJ, USA.

We own or control all commercial rights in our PARG program, subject to certain economic obligations pursuant to our exclusive, worldwide license to certain PARG inhibitors, including IDE161, with CRT and University of Manchester.

GSK101 (IDE705) - Pol Theta Helicase Inhibitor in tumors with Homologous Recombination Deficiency

We discovered GSK101 (IDE705), our DNA Polymerase Theta, or Pol Theta, Helicase inhibitor clinical development candidate, and evaluated GSK101 in preclinical studies in collaboration with GSK. GSK101 targets the helicase domain of the Pol Theta protein for patients having solid tumors with BRCA or other mutations associated with HRD.

Pol Theta is involved in a DNA repair process called microhomology mediated end joining, or MMEJ, that is utilized when homologous recombination mediated repair is compromised, as happens in the case of certain BRCA1 or BRCA2 mutations. The expression of Pol Theta is largely absent in normal cells, but tumor cells harboring double strand break repair defects, such as BRCA1 or BRCA2 mutations, show higher Pol Theta expression and synthetic lethality when Pol Theta is inhibited. Pol Theta is a large protein with two functional domains: a DNA polymerase domain and an ATP-dependent DNA helicase domain, sometimes referred to as an ATPase domain, linked by a RAD51 central region.

GSK is evaluating GSK101 in combination with niraparib, the GSK small molecule inhibitor of PARP for the treatment of patients having tumors with BRCA or other HR mutations, or HRD, in a GSK-sponsored Phase 1 clinical trial. GSK has dosed the first patient and enrollment is ongoing in the dose escalation portion of this study.

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GSK is leading clinical development of GSK101 pursuant to the Collaboration, Option and License Agreement with GSK, or GSK Collaboration Agreement. GSK is responsible for all research and development costs for the Pol Theta program.

We have the potential to receive an additional $10.0 million milestone payment upon initiation of Phase 1 clinical dose expansion. In August 2023, we achieved and earned a $7.0 million milestone based on acceptance of the IND by the FDA, for which payment was received in October 2023. An earlier preclinical development $3.0 million milestone payment from GSK was achieved in August 2022 in connection with ongoing IND-enabling studies to support evaluation of GSK101.

We have the potential to earn further aggregate late-stage development and regulatory milestones of up to $465 million. Upon commercialization, we will be eligible to receive up to $475 million of commercial milestones, and tiered royalties on global net sales of GSK101 – ranging from high single-digit to sub-teen double-digit percentages, subject to certain customary reductions.

WRN Inhibitors in Tumors with High Microsatellite Instability

We are advancing our preclinical IND-enabling studies and other preclinical research in collaboration with GSK for an inhibitor targeting Werner Helicase, or WRN, for patients having tumors with high MSI.

WRN protein is a RecQ enzyme involved in the maintenance of genome integrity. Germline loss of function mutations in WRN lead to premature aging and pre-disposition to cancer. MSI is a change in the DNA content of a tumor cell in which the number of repeats of microsatellites, short repeated sequences of DNA, differ as cells divide. High MSI is present in about 15% of gastrointestinal tumor cancers, including in approximately 22% of stomach adenocarcinoma and 16% of colorectal cancer. Tumors with high MSI are routinely assessed in multiple diagnostic profiling tests.

WRN is a protein having several functional domains, and we have shown that the helicase functional domain of WRN is responsible for this synthetic lethal interaction, as reflected in our publication in Cell Press - iScience, Werner Syndrome Helicase is Required for the Survival of Cancer Cells with Microsatellite Instability (March 2019).

We have demonstrated in vivo efficacy with tumor regression and PD response in a relevant high MSI model. We have observed selectivity of our Werner Helicase inhibitor and validation of the synthetic lethal relationship to tumors with high MSI over tumors with MSS based on a lack of in vivo pharmacological response in relevant MSS xenograft models.

A Werner Helicase Inhibitor development candidate, or DC, has been selected in collaboration with GSK. We, in collaboration with GSK, have completed the IND-enabling GLP toxicology studies and we are targeting an IND submission in the second half of 2024 to enable first-in-human clinical evaluation of Werner Helicase Inhibitor DC for patients having tumors with high MSI. Subject to IND submission and clearance, GSK will lead clinical development for the Werner Helicase program. GSK is responsible for 80% of global research and development costs and IDEAYA is responsible for 20% of such costs. GSK holds a global, exclusive license to develop and commercialize the Werner Helicase Inhibitor DC.

In October 2023, we achieved and earned a $3 million milestone in connection with IND-enabling studies. We have the potential to earn up to an additional $17 million aggregate milestone payments through early Phase 1 clinical studies, including $7.0 million upon IND clearance. We are also eligible to receive additional future aggregate total development milestones of up to $465 million. Upon commercialization, we will be eligible to receive up to $475 million of commercial milestones, 50% of U.S. net profits and tiered royalties on global non-U.S. net sales of the Werner Helicase Inhibitor DC – ranging from high single-digit to sub-teen double-digit percentages, subject to certain customary reductions.

Next-Generation Precision Medicine Pipeline Programs

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We have initiated early preclinical research programs focused on pharmacological inhibition of several new targets, or NTs, for patients with solid tumors characterized by defined biomarkers based on genetic mutations and/or molecular signatures. We believe these research programs have the potential for discovery and development of first-in-class or unique-in-class or best-in-class therapeutics. We are targeting development candidate nominations in the second half of 2024 for multiple NTs, including a development candidate to treat MTAP-deletion solid tumors to enable a potential wholly-owned clinical combination with IDE397. Collectively, we believe these efforts will further advance our multi-pronged clinical and business strategy. We own or control all commercial rights in our next-generation NT programs.

New Target and Biomarker Discovery Platform

Since inception of the company, our core research has and continues to be focused on precision medicine oncology, with synthetic lethality as a central tenet. We have invested significantly and continue to invest in capabilities for identification and validation of new precision medicine targets and biomarkers for patient selection. For targets of interest, we advance our research to discover therapeutic drugs and to further qualify relevant biomarkers.

Prospectus Supplement - At-the-Market Facility

In June 2023, we entered into an Open Market Sales Agreement, or June 2023 Sales Agreement, with Jefferies LLC (Jefferies) relating to an at-the-market offering program under which we may offer and sell, from time to time at our sole discretion, shares of our common stock, par value $0.0001 per share (“common stock”), having aggregate gross proceeds of up to $250.0 million through Jefferies as sales agent.

During the quarter ended March 31, 2024, pursuant to the June 2023 Open Market Sales Agreement, with Jefferies as a sales agent, we sold an aggregate of 6,115,516 shares of common stock through at-the-market offerings for aggregate net proceeds of $215.9 million, after deducting underwriting discounts and commissions and other offering expenses, at a weighted average sales price of approximately $36.39 per share.

On January 19, 2024, we entered into a new Open Market Sales Agreement, or January 2024 Sales Agreement, with Jefferies relating to an at-the-market offering program under which we may offer and sell, from time to time at our sole discretion, shares of common stock having aggregate gross proceeds of up to $350.0 million through Jefferies as sales agent.

During the quarter ended March 31, 2024, pursuant to the January 2024 Sales Agreement, we sold an aggregate of 3,144,866 shares of common stock through at-the-market offerings for aggregate net proceeds of $127.6 million at a weighted average sales price of approximately $41.53 per share. As of March 31, 2024, approximately $219.4 million of common stock remained available to be sold under the ATM facility.

Subsequent to March 31, 2024, from April 1, 2024 through April 24, 2024, we sold an aggregate of 922,000 shares of common stock for aggregate gross proceeds of approximately $37.2 million at a weighted average sales price of approximately $40.40 per share through at-the-market offerings, generating net proceeds of approximately $36.5 million, after deducting underwriting discounts and commissions and other estimated offering expense, pursuant to the January 2024 Sales Agreement with Jefferies as sales agent. As of April 24, 2024, approximately $182.1 million of common stock remained available to be sold under the ATM facility.

We may cancel our at-the-market program at any time upon written notice, pursuant to its terms.

Corporate Update

We do not have any products approved for sale and have not generated any product revenue since inception. We have funded our operations primarily through the sale and issuance of common stock and the upfront payment and certain milestone payments received from GSK. As of March 31, 2024, we had cash, cash equivalents and marketable securities of $941.4 million, consisting primarily of money market funds, U.S. government securities, commercial paper, and corporate bonds.

Since our inception in June 2015, we have devoted substantially all of our resources to discovering and developing our product candidates. We have incurred significant operating losses to date and expect that our operating expenses

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will increase significantly as we advance our product candidates through preclinical and clinical development; seek regulatory approval, and prepare for, and, if approved, proceed to commercialization; acquire, discover, validate and develop additional product candidates; obtain, maintain, protect and enforce our intellectual property portfolio; and hire additional personnel. Certain program costs that contribute to our operating expenses have been and/or will be reimbursed by GSK pursuant to the GSK Collaboration Agreement, including 100% of costs we incur for research we perform in connection with the Pol Theta program and 80% of the aggregate program costs incurred by us and GSK for research each of us performs for the Werner Helicase program. We anticipate that payments which we may make to Amgen will also contribute to our operating expenses as they are reimbursed by us pursuant to the Amgen CTCSA, including 50% of external costs Amgen incurs in connection with the Amgen-sponsored and executed IDE397 / AMG 193 Combination Study. We anticipate that we will also incur costs in accordance with the Gilead CSCSA. Gilead will bear internal or external costs incurred in connection with its supply of Trodelvy. We will bear all internal and external costs and expenses associated with the conduct of the combination study. We further anticipate that we will also incur costs in accordance with the Merck CTCSA. Merck will provide KEYTRUDA for the combination study at no cost to us. We will bear all internal and external costs and expenses associated with the conduct of the combination study. In addition, we expect to incur additional costs associated with operating as a public company.

Our net losses were $39.6 million and $23.6 million for the three months ended March 31, 2024 and March 31, 2023, respectively. As of March 31, 2024, we had an accumulated deficit of $387.9 million.

Our ability to generate product revenue will depend on the successful development, regulatory approval and eventual commercialization of one or more of our product candidates, ourselves, or for some programs, in collaboration with our strategic partners.

Until such time as we can generate significant revenue from product sales, if ever, we expect to finance our operations through the sale of equity, debt financings, or other capital sources, including potential collaborations with other companies or other strategic transactions. Adequate funding may not be available to us on acceptable terms, or at all. If we fail to raise capital or enter into such agreements as and when needed, we may have to significantly delay, scale back or discontinue the development and commercialization of our product candidates.

As of March 31, 2024, we had cash, cash equivalents, and short-term and long-term marketable securities of $941.4 million.

We believe that our cash, cash equivalents, and short-term and long-term marketable securities will be sufficient to fund our planned operations for at least twelve months from the date of the issuance of our Quarterly Report on Form 10-Q filed May 7, 2024.

These funds will support our efforts through potential achievement of multiple preclinical and clinical milestones across multiple programs.

Components of Operating Results

Collaboration Revenues

To date, we have not generated any revenue from product sales, and we do not expect to generate any revenue from product sales unless and until we are able to initiate a registrational clinical trial, obtain regulatory approval and commercialize one of our product candidates in the future. Our revenue consists exclusively of collaboration revenue under the GSK Collaboration Agreement, including amounts that are recognized related to previously received upfront payments and amounts due and payable to us for research and development services. The amount of revenue recognized related to the GSK Collaboration Agreement, including as related to the previously received upfront payment or to certain development milestone payments, may vary considerably by period and certain components thereof may generally decrease year-over-year as we satisfy remaining performance obligations, for example, relating to the Pol Theta and WRN R&D Services. As of March 31, 2024, we have fully recognized the contract liabilities related to the upfront payment and reimbursements for the research and development performance obligations under the GSK Collaboration Agreement. There are no remaining contract liabilities as of March 31, 2024 as we concluded all the research and development performance obligations under the GSK Collaboration Agreement. The future revenue recognition will be contingent on additional milestone earned, profit sharing and royalties on any net product sales under our collaborations. We expect that any revenue we recognize or generate under the GSK Collaboration Agreement will fluctuate from period to period due to period to period variability in milestone payments and other payments.

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Operating Expenses

Research and Development Expenses

Substantially all of our research and development expenses consist of expenses incurred in connection with discovery and development of our product candidates. These expenses include certain payroll and personnel-related expenses, including salaries, employee benefit costs and stock-based compensation expenses for our research and product development employees, fees to third parties to conduct certain research and development activities on our behalf including fees to CMOs and CROs in support of manufacturing and clinical activity for darovasertib, IDE397, IDE161 and WRN, consulting costs, costs for laboratory supplies, costs for product licenses and allocated overhead, including rent, equipment, depreciation, information technology costs and utilities. We expense both internal and external research and development expenses as they are incurred.

We have entered into various agreements with CMOs and CROs. Our research and development accruals are estimated based on the level of services performed, progress of the studies, including the phase or completion of events, and contracted costs. The estimated costs of research and development provided, but not yet invoiced, are included in accrued liabilities on the balance sheet. If the actual timing of the performance of services or the level of effort varies from the original estimates, we will adjust the accrual accordingly. Payments made to CMOs and CROs under these arrangements in advance of the performance of the related services are recorded as prepaid expenses and other current assets until the services are rendered.

Costs of certain activities, such as preclinical studies, are generally recognized based on an evaluation of the progress to completion of specific tasks. Nonrefundable payments made prior to the receipt of goods or services that will be used or rendered for future research and development activities are deferred and capitalized as prepaid expenses and other current assets on our balance sheet. The capitalized amounts are recognized as expense as the goods are delivered or the related services are performed.

We do not allocate our internal costs by product candidate, including internal costs, such as payroll and other personnel expenses, laboratory supplies and allocated overhead. With respect to internal costs, several of our departments support multiple product candidate research and development programs, and therefore the costs cannot be allocated to a particular product candidate or development program. The following table summarizes our external clinical development expenses by program:

	Three Months Ended
	March 31, 2024		December 31, 2023
External clinical development expenses (1):
Darovasertib	$	10,869	$	8,050
IDE397 (2)		2,926		3,499
IDE161		2,695		3,132
Personnel related and stock-based compensation		12,254		10,213
Other research and development expenses		14,061		13,876
Total research and development expenses	$	42,805	$	38,770

	Three Months Ended
	March 31, 2024		March 31, 2023
External clinical development expenses (1):
Darovasertib	$	10,869	$	4,720
IDE397 (2)		2,926		3,251
IDE161		2,695		723
Personnel related and stock-based compensation		12,254		8,870
Other research and development expenses		14,061		10,295
Total research and development expenses	$	42,805	$	27,859

(1)External clinical development expenses include manufacturing and clinical trial costs. These expenses are primarily for services provided by external consultants, CMOs and CROs.

(2)IDE397 includes costs from Amgen Clinical Trial Collaboration and Supply Agreement.

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We are focusing substantially all of our resources on the development of our product candidates. We expect our research and development expenses to increase substantially during the next few years, as we seek to initiate and/or advance clinical trials for our product candidates, complete our clinical program, pursue regulatory approval of our product candidates and prepare for a possible commercial launch. Predicting the timing or the cost to complete our clinical program or validation of our commercial manufacturing and supply processes is difficult and delays may occur because of many factors, including factors outside of our control. For example, if the FDA or other regulatory authorities were to require us to conduct clinical trials beyond those that we currently anticipate, or if we experience significant delays in enrollment in any of our clinical trials, we could be required to expend significant additional financial resources and time on the completion of clinical development. Furthermore, we are unable to predict when or if our product candidates will receive regulatory approval with any certainty.

General and Administrative Expenses

General and administrative expenses consist primarily of payroll and personnel-related expenses, including salaries, employee benefit costs and stock-based compensation expense, professional fees for legal, patent, consulting, accounting and tax services, allocated overhead, including rent, equipment, depreciation, information technology costs and utilities, and other general operating expenses not otherwise classified as research and development expenses.

We anticipate that our general and administrative expenses will increase, as a result of increased personnel costs, including salaries, benefits and stock-based compensation expense, patent costs for our product candidates, expanded infrastructure and higher consulting, legal and accounting services associated with maintaining compliance with our Nasdaq stock exchange listing and requirements of the Securities and Exchange Commission, or the SEC, investor relations costs and director and officer insurance policy premiums associated with being a public company.

Other Income (Expense)

Interest Income and Other Income (Expense), Net

Interest income and other income (expense), net consists primarily of interest income earned on our cash, cash equivalents and marketable securities.

Results of Operations

A discussion regarding our financial condition and results of operations for the three months ended March 31, 2024 compared to the three months ended December 31, 2023 and three months ended March 31, 2023 is presented below.

Comparison of Three Months Ended March 31, 2024 and December 31, 2023

The following table summarizes our results of operations for the periods indicated (in thousands):

	Three Months Ended
	March 31, 2024			December 31, 2023			Change			% Change
Revenue:
Collaboration revenue	$	—		$	3,923		$	(3,923	)		(100	%)
Operating expenses:
Research and development		42,805			38,770			4,035			10	%
General and administrative		8,212			7,068			1,144			16	%
Loss from operations		(51,017	)		(41,915	)		(9,102	)		22	%
Interest income and other income, net		11,445			7,960			3,485			44	%
Net loss	$	(39,572	)	$	(33,955	)	$	(5,617	)		17	%

Collaboration Revenue

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There was no collaboration revenue recognized for the three months ended March 31, 2024 compared to $3.9 million for the three months ended December 31, 2023. We completed all performance obligations related to the upfront payment under the GSK Collaboration Agreement as of December 31, 2023. Future collaboration revenue recognized under the GSK Collaboration Agreement will be related to future milestone payments as they are earned.

Research and Development Expenses

Research and development expenses increased by $4.0 million, or 10%, during the three months ended March 31, 2024 compared to the three months ended December 31, 2023 due to an increase of $3.9 million primarily driven by our potentially registration-enabling darovasertib clinical trial and Werner Helicase program expenses, $0.8 million in stock-based compensation related to our annual option grants and $1.2 million in personnel-related expenses, including salaries and benefits to support our growth, and $0.3 million in costs for facilities and software to support our research and development programs, which was partially offset by a decrease of $2.2 million driven by timing of clinical pharmacology studies and CMC manufacturing costs for darovasertib.

General and Administrative Expenses

General and administrative expenses increased by $1.1 million, or 16%, during the three months ended March 31, 2024 compared to the three months ended December 31, 2023. The increase in general and administrative expenses was primarily due to increases of $0.7 million in stock-based compensation related to our annual option grants and $0.4 million personnel-related expenses, including salaries and benefits to support our growth.

Interest Income and Other Income (Expense), Net

Interest income increased by $3.5 million, or 44%, during the three months ended March 31, 2024 compared to the three months ended December 31, 2023, primarily due to higher investment balances and interest rates.

Comparison of Three Months Ended March 31, 2024 and 2023

The following table summarizes our results of operations for the periods indicated (in thousands):

	Three Months Ended March 31,
	2024			2023			Change			% Change
Revenue:
Collaboration revenue	$	—		$	7,880		$	(7,880	)		(100	%)
Operating expenses:
Research and development		42,805			27,859			14,946			54	%
General and administrative		8,212			6,300			1,912			30	%
Loss from operations		(51,017	)		(26,279	)		(24,738	)		94	%
Interest income and other income, net		11,445			2,639			8,806			334	%
Net loss	$	(39,572	)	$	(23,640	)	$	(15,932	)		67	%

Collaboration Revenue

There was no collaboration revenue recognized for the three months ended March 31, 2024 compared to $7.9 million for the three months ended March 31, 2023. We completed all performance obligations related to the upfront payment under the GSK Collaboration Agreement as of December 31, 2023. Future collaboration revenue recognized under the GSK Collaboration Agreement will be related to future milestone payments as they are earned.

Research and Development Expenses

Research and development expenses increased by $14.9 million, or 54%, during the three months ended March 31, 2024 compared to the three months ended March 31, 2023. The increase in research and development expenses was primarily due to increases of $11.0 million in fees paid to CROs, CMOs and consultants related to the advancement of our lead product candidates through preclinical and clinical studies, $1.7 million in stock-based compensation and

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$1.7 million in personnel-related expenses, including salaries and benefits, to support our growth, and $0.5 million in costs for laboratory supplies, facilities, and software to support our research and development programs.

General and Administrative Expenses

General and administrative expenses increased by $1.9 million, or 30%, during the three months ended March 31, 2024 compared to three months ended March 31, 2023. The increase in general and administrative expenses was primarily due to increases of $0.8 million for consulting and legal services, and $1.0 million in stock-based compensation and $0.3 million in personnel-related expenses, including salaries and benefits, related to an increase in headcount to support our growth, partially offset by a decrease of $0.2 million in facility costs due to larger allocation to research & development expenses.

Interest Income and Other Income (Expense), Net

Interest income increased by $8.8 million, or 334%, during the three months ended March 31, 2024 compared to the three months ended March 31, 2023, primarily due to higher investment balances and interest rates.

Liquidity and Capital Resources; Plan of Operations

Sources of Liquidity

We have funded our operations primarily through the sale and issuance of common stock and the upfront payment and certain milestone payments received from GSK. As of March 31, 2024, we had cash, cash equivalents and marketable securities of $941.4 million, consisting primarily of money market funds, U.S. government securities, commercial paper, and corporate bonds.

Material Cash Requirements

We have incurred net losses since our inception. For the three months ended March 31, 2024 and three months ended March 31, 2023, we had net losses of $39.6 million and $23.6 million, respectively, and we expect to incur substantial additional losses in future periods. As of March 31, 2024, we had an accumulated deficit of $387.9 million. Based on our current business plan, we believe that our existing cash, cash equivalents and marketable securities will be sufficient to fund our planned operations for at least the next 12 months from the issuance date of this Quarterly Report on Form 10-Q.

To date, we have not generated any product revenue. We do not expect to generate any meaningful product revenue unless and until we obtain regulatory approval of and commercialize any of our product candidates, and we do not know when, or if, it will occur. We expect to continue to incur significant losses for the foreseeable future, and we expect the losses to increase as we continue the development of, and seek regulatory approvals for, our product candidates and begin to commercialize any approved products. We are subject to all of the risks typically related to the development of new product candidates, and we may encounter unforeseen expenses, difficulties, complications, delays and other unknown factors that may adversely affect our business. Moreover, we expect to incur additional costs associated with operating as a public company.

We will continue to require additional capital to develop our product candidates and fund operations for the foreseeable future. We may seek to raise capital through private or public equity or debt financings, collaboration or other arrangements with corporate sources, or through other sources of financing. Adequate additional funding may not be available to us on acceptable terms or at all. Our failure to raise capital as and when needed would have a negative impact on our financial condition and our ability to pursue our business strategies. We anticipate that we will need to raise substantial additional capital, the requirements for which will depend on many factors, including:

•the scope, timing, rate of progress and costs of our drug discovery, preclinical development activities, laboratory testing and clinical trials for our product candidates;

•the number and scope of clinical programs we decide to pursue;

•the scope and costs of manufacturing development and commercial manufacturing activities;

•the extent to which we acquire or in-license other product candidates and technologies;

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•the cost, timing and outcome of regulatory review of our product candidates;

•the costs of preparing, filing and prosecuting patent applications, maintaining and enforcing our intellectual property rights and defending intellectual property-related claims;

•our ability to establish and maintain collaborations on favorable terms, if at all;

•our efforts to enhance operational systems and our ability to attract, hire and retain qualified personnel, including personnel to support the development of our product candidates;

•the costs associated with being a public company; and

•the cost and timing associated with commercializing our product candidates, if they receive marketing approval.

A change in the outcome of any of these or other variables with respect to the development of any of our product candidates could significantly change the costs and timing associated with the development of that product candidate. Furthermore, our operating plans may change in the future, and we will continue to require additional capital to meet operational needs and capital requirements associated with such operating plans. If we raise additional funds by issuing equity securities, our stockholders may experience dilution. Any future debt financing into which we enter may impose upon us additional covenants that restrict our operations, including limitations on our ability to incur liens or additional debt, pay dividends, repurchase our common stock, make certain investments or engage in certain merger, consolidation or asset sale transactions. Any debt financing or additional equity that we raise may contain terms that are not favorable to us or our stockholders. If we are unable to raise additional funds when needed, we may be required to delay, reduce, or terminate some or all of our development programs and clinical trials. We may also be required to sell or license to others rights to our product candidates in certain territories or indications that we would prefer to develop and commercialize ourselves.

We lease our laboratory and office facilities in 7000 Shoreline Court, South San Francisco, California under an operating lease with an expiration date in September 2024. In May 2018, we amended our 7000 Shoreline Court facility lease agreement to expand the size of the original premises by adding approximately 7,340 rentable square feet of additional space. In September 2019, we further amended our 7000 Shoreline Court facility lease agreement to expand the size of the premises by adding 5,588 rentable square feet of additional space. In April 2024, we again amended our 7000 Shoreline Court facility lease agreement to extend the expiration date from July 2024 to September 2024. As a result, we expect to make the total lease payments of $1.5 million through September 2024.

In June 2023, we entered into a lease agreement for 43,966 square feet of space at 5000 Shoreline Court, South San Francisco, California. The lease term is expected to commence in the third quarter of 2024 and the lease term is one hundred twenty months.

In November 2023, we additionally entered into a lease for an office located in San Diego, California, where we occupy approximately 5,700 square feet of office space. The lease commenced in December 2023 and expires in March 2028.

We enter into contracts in the normal course of business with third-party contract organizations for preclinical and clinical studies and testing, manufacture and supply of our preclinical and clinical materials and providing other services and products for operating purposes. These contracts generally provide for termination following a certain period after notice, and therefore we believe that our non-cancelable obligations under these agreements are not material.

Pursuant to the GSK Collaboration Agreement, GSK holds a global, exclusive license to develop and commercialize WRN products arising out of the WRN program. We and GSK are collaborating on ongoing preclinical research for the WRN program, and GSK will lead clinical development for the WRN program, with IDEAYA responsible for 20% and GSK responsible for 80% of such global research and development costs. The cost-sharing percentages will be adjusted based on the actual ratio of U.S. to global profits for WRN products, as measured three and six years after global commercial launch thereof.

In September 2018, we entered into a license agreement with Novartis to develop and commercialize Novartis’ LXS196 (also known as IDE196), a Phase 1 PKC inhibitor, for the treatment of cancers having GNAQ and GNA11

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mutations. We renamed Novartis’ LXS196 oncology as IDE196, and which has a non-proprietary name of darovasertib. Under the license agreement, Novartis granted to us a worldwide, exclusive, sublicensable license to research, develop, manufacture, and commercialize certain defined compounds and products, including IDE196 and certain other PKC inhibitors as well as companion diagnostic products, collectively referred to as the licensed products, for any purpose.

We paid Novartis an upfront payment of $2.5 million and issued 263,615 shares of our Series B redeemable convertible preferred stock concurrently with the execution of the license agreement. Subject to completion of certain clinical and regulatory development milestones, we agreed to make milestone payments in the aggregate of up to $9.0 million, and subject to achievement of certain commercial sales milestones, we agreed to make milestone payments in the aggregate of up to $20.0 million. We also agreed to pay mid to high single-digit tiered royalty payments based on annual worldwide net sales of licensed products, payable on a licensed product-by-licensed product and country by country basis until the latest of the expiration of the last to expire exclusively licensed patent, the expiration of regulatory exclusivity, and the ten year anniversary of the first commercial sale of such product in such country. The royalty payments are subject to reductions for lack of patent coverage, loss of market exclusivity, and payment obligations for third-party licenses.

In March 2020, we entered into the Pfizer Agreement. Pursuant to the Pfizer Agreement, as amended in September 2020, April 2021, September 2021 and May 2023, Pfizer supplies us with their MEK inhibitor, binimetinib, and their cMET inhibitor, crizotinib, to evaluate combinations of darovasertib independently with each of the Pfizer compounds, in patients with tumors harboring activating GNAQ or GNA11 mutations. Under the Pfizer Agreement, we are the sponsor of the combination studies and will provide darovasertib and pay for the costs of the combination studies. Pfizer will provide binimetinib and crizotinib for use in the clinical trial at no cost to us. We have further expanded the scope of our relationship with Pfizer, entering into additional agreements to facilitate evaluation of darovasertib in combination with crizotinib in a potential registrations clinical trial in MUM and separately, in combination with crizotinib in other cMET-driven tumor indications.

In March 2022, we and Pfizer entered into the Second Pfizer Agreement pursuant to which we may, subject to FDA feedback and guidance, evaluate darovasertib and crizotinib as a combination therapy in MUM in a planned Phase 2/3 potential registration-enabling clinical trial. Pursuant to the Second Pfizer Agreement, we are the sponsor of the planned combination trial and we will provide darovasertib and pay for the costs of the combination trial; Pfizer will provide crizotinib for the planned combination trial at no cost to us for up to an agreed-upon number of MUM patients. Separately, in March 2022, we and Pfizer also entered into the Third Pfizer Agreement pursuant to which we may, subject to preclinical validation and FDA feedback and guidance, evaluate darovasertib and crizotinib, as a combination therapy in cMET-driven tumors such as NSCLC and/or HCC in a Phase 1 clinical trial. Pursuant to the Third Pfizer Agreement, we are the sponsor of the planned combination trial, and we will provide darovasertib and pay for the costs of the combination trial; Pfizer will provide crizotinib for the planned combination trial at no cost to us. In May 2023, we continued our relationship with Pfizer by entering into Amendment No. 4 to the Pfizer Agreement relating to the supply of crizotinib in support of this Phase 2 clinical trial, pursuant to which Pfizer will continue to provide us with an additional defined quantity of crizotinib at no cost.

We also expanded our relationship with Pfizer in May 2023 under an Amendment No. 1 to the Second Pfizer Agreement to support the Phase 2/3 registrational trial to evaluate darovasertib and crizotinib as a combination therapy in MUM. Under the as-amended Second Pfizer Agreement, Pfizer will provide us with a first defined quantity of crizotinib at no cost, as well as an additional second defined quantity of crizotinib at a lump-sum cost. Under Amendment No. 1 to the Second Pfizer Agreement, we also terminated the Third Pfizer Agreement.

In January 2022, we exercised our option for an exclusive worldwide license rights covering a broad class of PARG inhibitors from Cancer Research Technology Ltd. (CRT) and the University of Manchester, and in connection therewith, paid a one-time option exercise fee of £250,000.

In addition to an upfront fee of £100,000 and the one-time option exercise fee of £250,000, each of which have been paid, we have certain potential milestone-dependent financial obligations, including: (a) subject to completion of specific development and regulatory approval events for development of a PARG inhibitor in oncologic diseases, payments of up to £19.5 million per broad disease classification block – for example, in oncologic diseases, up to £13.0 million aggregate for a first achievement of such clinical and regulatory milestones and up to £6.5 million aggregate for a second achievement of such clinical and regulatory milestones; (b) subject to certain sales-based milestones based on net sales of licensed products. payments of up to £9 million per broad disease classification

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block – for example, in oncologic diseases, up to £6.0 million aggregate for a first achievement of such sales milestones and up to £3.0 million aggregate for a second achievement of such sales milestones; and (c) low single-digit tiered royalty payments based on aggregate worldwide net sales of al products, payable on a product-by-product and country-by-country basis until the later of the last-to-expire patent covering such product in such country and the ten year anniversary of the first commercial sale of such licensed product in such country. The royalty payments are subject to reductions for payment obligations in the event third-party licenses are required to develop or commercialize the product or if the product is not covered by certain patents.

In April 2023, we incurred an obligation to pay milestone payments in an aggregate amount of £750,000 to CRT based upon the achievement of certain milestones relating to first and second tumor histologies in connection with the Phase 1 portion of the Phase 1/2 clinical trial in oncologic diseases. After the achievement of this milestone, we will be obligated to make future milestone payments to CRT aggregating up to £18.75 million upon the achievement of specific development and regulatory approval events for development of a PARG inhibitor in oncologic diseases. This includes an aggregate of up to £1.5 million and up to £2.25 million for the achievement of certain Phase 2 and Phase 3 development milestones, respectively, in each case as relating to first (e.g., a breast cancer) and second (e.g., ovarian cancer) tumor histologies.

We pay all expenses associated with prosecution and maintenance and each party bears its own costs for enforcement. If we abandon the patents covering inventions developed under the agreement as project intellectual property, Cancer Research UK will thereafter be responsible for prosecuting and maintaining such patents. If we abandon such patents, Cancer Research UK and University of Manchester will be responsible for paying the expenses associated with the prosecution and maintenance of such patents.

Following our exercise of the option, if we sublicense certain intellectual property developed under the agreement or Cancer Research UK background patents specifically relating to PARG, we will also have an obligation to pay to Cancer Research UK low double digit percentage of sublicense revenue we receive, if any. If the agreement is terminated due to our material breach, then we are eligible to receive a percentage of sublicensing revenue that Cancer Research UK receives for licensing intellectual property.

In July 2022, we entered into the Amgen CTCSA to clinically evaluate IDE397 in combination with AMG 193 in patients having MTAP-null solid tumors, in a Phase 1/2 clinical trial. Under the mutually non-exclusive Amgen CTCSA, we will provide IDE397 drug supply to Amgen, who will be the sponsor of the Phase 1 clinical combination trial evaluating IDE397 and AMG 193. Each party will pay for fifty percent (50%) of the external third-party costs of the combination study. Each party will be responsible for its own internal costs and expenses in support of the combination study. We and Amgen will jointly oversee clinical development of the combination therapy through a Joint Oversight Committee responsible for coordinating all regulatory and other activities under the Amgen CTCSA. The parties will jointly own collaboration data and combination-related intellectual property, if any, arising from the combination clinical trial. We and Amgen each retain commercial rights to our respective compounds, including with respect to use as a monotherapy agent or combination agent.

In November 2023, we entered into the Gilead CSCSA with Gilead to clinically evaluate IDE397 in combination with Trodelvy (sacituzumab-govitecan-hziy), a Trop-2 directed ADC, in patients having MTAP-deletion bladder cancer, in a Phase 1 clinical trial. Under the mutually non-exclusive Gilead CSCSA, we will receive Trodelvy drug supply from Gilead and will sponsor the Phase 1 clinical combination trial evaluating ID397 and Trodelvy. Gilead will bear internal or external costs incurred in connection with its supply of Trodelvy. We will bear all internal and external costs and expenses associated with the conduct of the combination study. We and Gilead will jointly oversee clinical development of the combination therapy through a Joint Steering Committee responsible for coordinating all regulatory and other activities under the Gilead CSCSA. We and Gilead each retain commercial rights to our respective compounds, including with respect to use as a monotherapy agent or combination agent.

In March 2024, we entered into the Merck CTCSA with Merck. We are planning to evaluate IDE161 in a combination study with KEYTRUDA® (pembrolizumab), Merck's anti-PD-1 therapy, in patients with MSI-high and MSS endometrial cancer. Pursuant to the Merck CTCSA, we are the sponsor of the combination study and we will provide the IDE161 compound and pay for the costs of the combination study. Merck will provide KEYTRUDA at no cost to us. We will jointly own clinical data from the combination and all inventions relating to the combined use

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of IDE161 and pembrolizumab. Each party retains commercial rights to its respective compounds, including with respect to use as a monotherapy or combination agent.

Adequate additional funding may not be available to us on acceptable terms or at all.

See the section of this Quarterly Report on Form 10-Q titled “Part I, Item 1A. – Risk Factors” for additional risks associated with our substantial capital requirements.

Off-Balance Sheet Arrangements

We have not entered into any off-balance sheet arrangements as defined in the rules and regulations of the SEC.

Summary Statement of Cash Flows

The following table sets forth the primary sources and uses of cash, cash equivalents, and restricted cash for each of the periods presented below (in thousands):

	Three Months Ended March 31,
	2024			2023
Net cash provided by (used in):
Operating activities	$	(43,813	)	$	(27,842	)
Investing activities		(353,971	)		23,521
Financing activities		349,111			2,926
Net decrease in cash, cash equivalents and restricted cash	$	(48,673	)	$	(1,395	)

Cash Flows from Operating Activities

Net cash used in operating activities was $43.8 million for the three months ended March 31, 2024. Cash used in operating activities was primarily due to the use of funds in our operations to develop our product candidates resulting in a net loss of $39.6 million, adjusted for net non-cash charges of $1.1 million and changes in net operating assets and liabilities of $5.3 million. Our non-cash charges consisted of $6.3 million in stock-based compensation, $0.6 million in depreciation and $0.5 million of the amortization of right of use assets, partially offset by $6.3 million accretion of discounts on marketable securities. The net change in our operating assets and liabilities consisted primarily of $3.1 million in prepaid and other assets, $1.3 million accrued and other liabilities due to CRO fees in support of research and manufacturing activities, $0.5 million in lease liabilities, and $0.5 million in accounts payable.

Net cash used in operating activities was $27.8 million for the three months ended March 31, 2023. Cash used in operating activities was primarily due to the use of funds in our operations to develop our product candidates resulting in a net loss of $23.6 million, adjusted for net non-cash charges of $3.1 million and changes in net operating assets and liabilities of $7.3 million. Our non-cash charges consisted of $3.7 million in stock-based compensation, $0.6 million in depreciation and $0.4 million amortization of right-of-use assets, partially offset by $1.6 million accretion of discount on marketable securities. The net change in our operating assets and liabilities consisted primarily of decreases of $7.5 million in contract liabilities due to revenue recognized under the GSK Collaboration Agreement, $0.5 million in lease liabilities, $0.4 million in accrued liabilities, and $0.3 million in accounts receivable from GSK for estimated program costs under the GSK Collaboration Agreement, partially offset by a decrease of $1.4 million in prepaid and other current assets.

Cash Flows from Investing Activities

Net cash used in investing activities was $354.0 million for the three months ended March 31, 2024, which consisted primarily of $475.8 million used to purchase marketable securities and $1.3 million used to purchase property and equipment, partially offset by $123.1 million provided by maturities of marketable securities.

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Net cash provided by investing activities was $23.5 million for the three months ended March 31, 2023, which consisted of $95.9 million provided by maturities of marketable securities, partially offset by $72.3 million used to purchase marketable securities.

Cash Flows from Financing Activities

Net cash provided by financing activities was $349.1 million for the three months ended March 31, 2024, which consisted primarily of $343.7 million of net proceeds from sales under our ATM facility and $5.5 million of proceeds from exercise of common stock options.

Net cash provided by financing activities was $2.9 million for the three months ended March 31, 2023, which consisted primarily of $2.6 million of net proceeds from sales under our ATM facility and $0.4 million of net proceeds from exercise of common stock options.

Critical Accounting Policies

Our financial statements have been prepared in accordance with U.S. generally accepted accounting principles, or GAAP. The preparation of these financial statements requires us to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the financial statements and the reported revenue recognized and expenses incurred during the reporting periods. Our estimates are based on our historical experience and on various other factors that we believe are reasonable under the circumstances, the results of which form the basis for making judgments about the carrying value of assets and liabilities that are not readily apparent from other sources. Actual results may differ from these estimates under different assumptions or conditions. We believe that the accounting policies discussed below are critical to understanding our historical and future performance, as these policies relate to the more significant areas involving management’s judgments and estimates.

For more detail on our critical accounting policies, refer to Note 2 in the unaudited interim condensed financial statements appearing elsewhere in this Quarterly Report on Form 10-Q, and the notes to the financial statements appearing elsewhere in our Annual Report on Form 10-K filed with the SEC on February 20, 2024. For the three months ended March 31, 2024, there were no material changes to our critical accounting policies from those disclosed in our Annual Report on Form 10-K filed with the SEC on February 20, 2024.

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Item 3. Quantitative and Qualitative Disclosures About Market Risk.

Interest Rate Sensitivity

The market risk inherent in our financial instruments and in our financial position represents the potential loss arising from adverse changes in interest rates or exchange rates. As of March 31, 2024, we had cash, cash equivalents and marketable securities of $941.4 million, consisting of bank deposits, interest-bearing money market funds, investments in U.S. government securities, commercial paper, and corporate bonds, for which the fair value would be affected by changes in the general level of U.S. interest rates. Even if the fair value of certain government securities, commercial paper, and corporate bonds is affected by changes in U.S. interest rates, the principal of such instruments will be due to us upon maturity.

While we are seeing, and expect to continue to see, record inflation and elevated interest rates due to geopolitical and macroeconomic events, such as the ongoing Ukraine-Russia conflict and related sanctions, the Israel-Hamas conflict, and the banking sector volatility, we do not believe that inflation, interest rate changes or exchange rate fluctuations have had a significant impact on our results of operations for any periods presented herein.

Item 4. Controls and Procedures.

Limitations on Effectiveness of Controls and Procedures

In designing and evaluating our disclosure controls and procedures, management recognizes that any controls and procedures, no matter how well designed and operated, can provide only reasonable assurance of achieving the desired control objectives. In addition, the design of disclosure controls and procedures must reflect the fact that there are resource constraints and that management is required to apply judgment in evaluating the benefits of possible controls and procedures relative to their costs.

Evaluation of Disclosure Controls and Procedures

Our management, with the participation of our Chief Executive Officer and Chief Financial Officer, evaluated, as of the end of the period covered by this Quarterly Report on Form 10-Q, the effectiveness of our disclosure controls and procedures (as defined in Rules 13a-15(e) and 15d-15(e) under the Exchange Act. Based on that evaluation, our Chief Executive Officer and Chief Financial Officer concluded that our disclosure controls and procedures were effective at the reasonable assurance level as of March 31, 2024.

Changes in Internal Control over Financial Reporting

There was no change in our internal control over financial reporting identified in connection with the evaluation required by Rule 13a-15(e) and 15d-15(e) of the Exchange Act that occurred during the period covered by this Quarterly Report on Form 10-Q that has materially affected, or is reasonably likely to materially affect, our internal control over financial reporting.

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PART II—OTHER INFORMATION

Item 1. Legal Proceedings.

From time to time, we may become involved in litigation or other legal proceedings. We are not currently a party to any litigation or legal proceedings that, in the opinion of our management, are likely to have a material adverse effect on our business. Regardless of outcome, litigation can have an adverse impact on our business, financial condition, results of operations and prospects because of defense and settlement costs, diversion of management resources and other factors.

Item 1A. Risk Factors.

In addition to other information contained elsewhere in this Quarterly Report on Form 10-Q, you should carefully consider the risk factors discussed in Part I, Item 1A. Risk Factors in our Annual Report on Form 10-K filed with the SEC on February 20, 2024 (the “Annual Report”), which could materially affect our business, financial condition, or future results. As of the date of this Quarterly Report on Form 10-Q, there have been no material changes to the risk factors disclosed in our Annual Report.

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Item 2. Unregistered Sales of Equity Securities and Use of Proceeds.

Unregistered Sales of Equity Securities

None.

Use of Proceeds from the Sale of Registered Securities

Not applicable.

Issuer Purchases of Equity Securities

None.

Item 3. Defaults Upon Senior Securities.

Not applicable.

Item 4. Mine Safety Disclosures.

Not applicable.

Item 5. Other information.

Not applicable.

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Exhibit Index

Item 6. Exhibits.

Exhibit Number	Exhibit Description	Incorporated by Reference			Filed Herewith
		Form	Date	Number
3.1	Amended and Restated Certificate of Incorporation.	8-K	5/28/2019	3.1
3.2	Amended and Restated Bylaws.	8-K	5/28/2019	3.2
4.1	Reference is made to Exhibits 3.1 through 3.2.
4.2	Form of Common Stock Certificate.	S-1/A	5/13/2019	4.2
4.3	Description of Common Stock.	10-K	2/20/2024	4.3
4.4	Form of April 2023 Pre-funded Warrant	8-K	4/27/2023	4.1
4.5	Form of October 2023 Pre-funded Warrant	8-K	10/27/2023	4.1
10.1†	Clinical Trial Collaboration and Supply Agreement by and between MSD International Business GmbH and IDEAYA Biosciences, Inc., dated as of March 8, 2024				X
31.1	Certification of the Chief Executive Officer pursuant to Rule 13a-14(a) and Rule 15d-14(a) under the Securities Exchange Act of 1934, as adopted pursuant to Section 302 of the Sarbanes-Oxley Act of 2002.				X
31.2	Certification of the Chief Financial Officer pursuant to Rule 13a-14(a) and Rule 15d-14(a) under the Securities Exchange Act of 1934, as adopted pursuant to Section 302 of the Sarbanes-Oxley Act of 2002.				X
32.1*	Certification pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002.				X
101.INS	Inline XBRL Instance Document – the instance document does not appear in the Interactive Data File because its XBRL tags are embedded within the Inline XBRL document.				X
101.SCH	Inline XBRL Taxonomy Extension Schema with Embedded Linkbase Documents .				X
104	Cover Page Interactive Data File (embedded with the Inline XBRL document)				X

† Certain information in this exhibit has been excluded pursuant to Regulation S-K, Item 601(b)(10).

* The certification attached as Exhibit 32.1 that accompanies this Quarterly Report on Form 10-Q is not deemed filed with the SEC and is not to be incorporated by reference into any filing of IDEAYA Biosciences, Inc. under the Securities Act of 1933, as amended, or the Securities Exchange Act of 1934, as amended, whether made before or after the date of this Form 10-Q, irrespective of any general incorporation language contained in such filing.

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SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned thereto duly authorized.

	IDEAYA Biosciences, Inc.
Date: May 7, 2024	By:	/s/ Yujiro Hata
		Yujiro Hata
		President and Chief Executive Officer
		(Principal Executive Officer)
Date: May 7, 2024	By:	/s/ Andres Ruiz Briseno
		Andres Ruiz Briseno
		Senior Vice President, Head of Finance and Investor Relations
		(Principal Financial and Accounting Officer)

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