smmt-20260630

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 EXCHANGE ACT OF 1934

For the quarterly period ended June 30, 2026


☐			TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from _________ to _________

Commission File Number: 001-36866

_______________________________

Summit Therapeutics Inc.

(Exact name of registrant as specified in its charter)

_____________________


Delaware						37-1979717
(State or other jurisdiction of incorporation or organization)						(I.R.S. Employer Identification No.)

601 Brickell Key Drive, Suite 1000,

Miami, FL

(Address of principal executive offices)

33131

(Zip Code)

305-203-2034

(Registrant’s telephone number, including area code)

Not Applicable

(Former name or former address and former fiscal year, if changed since last report)

_________________

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, $0.01 par value per share	SMMT	The Nasdaq Stock Market LLC

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, a 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 July 17, 2026, there were 797,749,602 shares of common stock, par value $0.01 per share, outstanding.

TABLE OF CONTENTS


		Page
Cautionary Note Regarding Forward-Looking Statements		1
PART I	FINANCIAL INFORMATION	3
Item 1.	Financial Statements (Unaudited)	3
	Condensed Consolidated Balance Sheets	3
	Condensed Consolidated Statements of Operations and Comprehensive Loss	4
	Condensed Consolidated Statements of Stockholders' Equity	5
	Condensed Consolidated Statements of Cash Flows	6
	Notes to Unaudited Condensed Consolidated Financial Statements	7
Item 2.	Management's Discussion and Analysis of Financial Condition and Results of Operations	20
Item 3.	Quantitative and Qualitative Disclosures About Market Risk	36
Item 4.	Controls and Procedures	36
PART II	OTHER INFORMATION	38
Item 1.	Legal Proceedings	38
Item 1A.	Risk Factors	39
Item 2.	Unregistered Sales of Equity Securities and Use of Proceeds	39
Item 3.	Defaults Upon Senior Securities	39
Item 4.	Mine Safety Disclosures	39
Item 5.	Other Information	39
Item 6.	Exhibits	40
Signatures		41

CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS

This Quarterly Report on Form 10-Q contains “forward-looking statements” within the meaning of the Private Securities Litigation Reform Act of 1995, Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), regarding the future financial performance, business prospects and growth of Summit Therapeutics Inc., that involve substantial risks and uncertainties. All statements contained in this Quarterly Report on Form 10-Q, other than statements of historical fact, including statements regarding our strategy, future operations, future financial position, future revenues, projected costs, prospects, plans and objectives of management, are forward-looking statements. The words “anticipate,” “believe,” “estimate,” “expect,” “intend,” “may,” “plan,” “predict,” “project,” “target,” “potential,” “will,” “would,” “could,” “should,” “continue,” and similar expressions are intended to identify forward-looking statements, although not all forward-looking statements contain these identifying words. The forward-looking statements in this Quarterly Report on Form 10-Q include, among other things, statements about:

•the ability to develop a successful product candidate under the License Agreement (as defined in Part I, Item 1 Financial Statements, Note 1 Organization);

•our ability to raise sufficient additional funds to make payments under the License Agreement, and fund ongoing operations and capital needs;

•the timing of and the ability to effectively execute clinical development of ivonescimab;

•the timing, costs, conduct and outcomes of clinical trials for any product candidates, including ivonescimab;

•our plans with respect to possible future collaborations and partnering arrangements;

•the potential benefits of possible future acquisitions or investments in other businesses, products or technologies;

•our plans to pursue research and development of other future product candidates;

•our estimates regarding the potential market opportunity and patient population for commercializing our product candidates, if approved for commercial use;

•our sales, marketing and distribution capabilities and strategy;

•our ability to establish and maintain arrangements with third parties, such as contract research organizations, contract manufacturing organizations, suppliers and distributors;

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

•our estimates regarding expenses, future revenues, capital requirements and needs for additional financing;

•the impact of government laws and regulations in the United States and in foreign countries;

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

•whether regulatory authorities determine that additional trials or data are necessary in order to accept a new drug application for review and/or approval;

•our competitive position;

•our ability to attract and retain key scientific or management personnel;

•the impact of public health epidemics, such as the novel coronavirus pandemic, natural disasters or geopolitical instability, the response to such events and the potential effects of such events on our business, financial results, supply chain and market;

•the outcome of pending, threatened, and future legal proceedings;

•our expectations regarding the anticipated timeline and our planned use of our cash, cash equivalents and short-term investments, future financial performance and our ability to continue as a going concern;

•estimates regarding stock-based compensation;

•general economic conditions, including economic slowdowns or other adverse economic conditions, such as periods of increased or prolonged inflation; and

•other risks and uncertainties, including those described under the heading “Risk Factors” included in this Quarterly Report on Form 10-Q and in our most recent Annual Report on Form 10-K for the year ended December 31, 2025, filed with the U.S. Securities and Exchange Commission (“SEC”) on February 23, 2026 (the “Annual Report”).

We may not actually achieve the plans, intentions or expectations disclosed in our forward-looking statements, and you should not place undue reliance on our forward-looking statements. Actual results or events could differ materially from the plans, intentions and expectations disclosed in the forward-looking statements we make. We have included important factors in the cautionary statements included in this Quarterly Report on Form 10-Q, particularly in the “Risk Factors” and

"Management's Discussion and Analysis of Financial Condition and Results of Operations" sections in this Quarterly Report on Form 10-Q, that we believe could cause actual results or events to differ materially from the forward-looking statements that we make. Our forward-looking statements do not reflect the potential impact of any future acquisitions, mergers, dispositions, joint ventures or investments we may make.

You should read this Quarterly Report on Form 10-Q and the documents that we have filed as exhibits to this Quarterly Report on Form 10-Q completely and with the understanding that our actual future results may be materially different from what we expect. We do not assume any obligation to update any forward-looking statements.

PART I - FINANCIAL INFORMATION

Item 1. Financial Statements.

Summit Therapeutics Inc.

Condensed Consolidated Balance Sheets

(in thousands, except share and per share data)

(Unaudited)


	June 30, 2026		December 31, 2025
Assets
Current assets:
Cash and cash equivalents	$	419,365	$	225,266
Restricted cash	317		316
Short-term investments	271,313		488,182
Prepaid expenses and other current assets	29,583		6,537
Total current assets	720,578		720,301

Non-current assets:
Property and equipment, net	1,781		1,059
Operating lease right-of-use assets	19,410		20,616
Goodwill	1,968		2,001
Other assets	8,448		7,205
Total assets	$	752,185	$	751,182

Liabilities and stockholders' equity
Current liabilities:
Accounts payable	$	22,896	$	20,292
Accrued liabilities	65,055		32,100
Accrued compensation	9,443		14,925
Operating lease liabilities, current portion	3,550		3,388
Other current liabilities	2,622		2,283
Total current liabilities	103,566		72,988

Non-current liabilities:
Operating lease liabilities, net of current portion	16,834		17,502
Other non-current liabilities	1,802		1,832
Total liabilities	122,202		92,322
Commitments and contingencies (Note 12)
Stockholders' equity:
Preferred stock, $0.01 par value, 20,000,000 shares authorized; none issued and outstanding at June 30, 2026 and December 31, 2025, respectively	—		—
Common stock, $0.01 par value: 1,000,000,000 shares authorized; 793,120,362 and 775,371,200 shares issued and outstanding at June 30, 2026 and December 31, 2025, respectively	7,931		7,754
Additional paid-in capital	3,324,000		2,947,805
Accumulated other comprehensive loss	(2,665)		(2,540)
Accumulated deficit	(2,699,283)		(2,294,159)
Total stockholders' equity	629,983		658,860
Total liabilities and stockholders' equity	$	752,185	$	751,182

The accompanying notes are an integral part of the unaudited condensed consolidated financial statements.

Summit Therapeutics Inc.

Condensed Consolidated Statements of Operations and Comprehensive Loss

(in thousands, except share and per share data)

(Unaudited)


	Three Months Ended June 30,				Six Months Ended June 30,
	2026		2025		2026		2025

Operating expenses:
Research and development (1)	$	157,733	$	208,021	$	290,351	$	259,286

General and administrative	62,763		360,416		125,357		376,002
Total operating expenses	220,496		568,437		415,708		635,288
Other income, net	4,796		2,729		10,584		6,667


Net loss	$	(215,700)	$	(565,708)	$	(405,124)	$	(628,621)

Net loss per share:
Basic and diluted	$	(0.28)	$	(0.76)	$	(0.52)	$	(0.85)
Weighted average common shares outstanding:
Basic and diluted	778,184,568		742,615,007		776,824,812		740,358,044
Other comprehensive income (loss):
Foreign currency translation adjustments	34		(189)		118		(334)

Unrealized loss on short-term investments	(67)		—		(243)		(133)
Comprehensive loss	$	(215,733)	$	(565,897)	$	(405,249)	$	(629,088)

(1) Refer to Note 11 – Related Party Transactions for expenses incurred.

The accompanying notes are an integral part of the unaudited condensed consolidated financial statements.

Summit Therapeutics Inc.

Condensed Consolidated Statements of Stockholders' Equity

(in thousands, except share data)

(Unaudited)


	Common Stock			Additional Paid-In Capital		Accumulated Other Comprehensive Loss		Accumulated Deficit		Total Stockholders' Equity
	Shares	Amount
Balance at December 31, 2025	775,371,200	$	7,754	$	2,947,805	$	(2,540)	$	(2,294,159)	$	658,860
Issuance of common stock under stock purchase plans and exercise of stock options	646,274	6		3,791		—		—		3,797
Stock-based compensation	—	—		72,791		—		—		72,791
Net other comprehensive loss	—	—		—		(92)		—		(92)
Net loss	—	—		—		—		(189,424)		(189,424)
Balance at March 31, 2026	776,017,474	$	7,760	$	3,024,387	$	(2,632)	$	(2,483,583)	$	545,932
Issuance of common stock upon exercise of stock options	670,453	7		3,658		—		—		3,665
Proceeds from at-the-market offering, net of commissions of $3,463 (2)	16,432,435	164		227,249		—		—		227,413
Stock-based compensation	—	—		68,706				—		68,706
Net other comprehensive loss	—	—		—		(33)		—		(33)
Net loss	—	—		—		—		(215,700)		(215,700)
Balance at June 30, 2026	793,120,362	$	7,931	$	3,324,000	$	(2,665)	$	(2,699,283)	$	629,983


	Common Stock			Additional Paid-In Capital		Accumulated Other Comprehensive Loss		Accumulated Deficit		Total Stockholders' Equity
	Shares	Amount
Balance at December 31, 2024	737,626,004	$	7,376	$	1,598,230	$	(2,285)	$	(1,214,573)	$	388,748
Issuance of common stock under stock purchase plans and exercise of stock options and warrants (2)	3,983,386	40		7,637		—		—		7,677
Stock-based compensation	—	—		11,096		—		—		11,096
Net other comprehensive loss	—	—		—		(278)				(278)
Net loss	—	—		—		—		(62,913)		(62,913)
Balance at March 31, 2025	741,609,390	$	7,416	$	1,616,963	$	(2,563)	$	(1,277,486)	$	344,330
Issuance of common stock upon exercise of stock options and warrants (2)	1,197,282	12		2,210		—		—		2,222
Stock-based compensation	—	—		478,784		—		—		478,784
Net other comprehensive loss	—	—		—		(189)		—		(189)
Net loss	—	—		—		—		(565,708)		(565,708)
Balance at June 30, 2025	742,806,672	$	7,428	$	2,097,957	$	(2,752)	$	(1,843,194)	$	259,439

(2) Refer to Note 11 – Related Party Transactions.

The accompanying notes are an integral part of the unaudited condensed consolidated financial statements.

Summit Therapeutics Inc.

Condensed Consolidated Statements of Cash Flows

(in thousands)

(Unaudited)


	Six Months Ended June 30,
	2026		2025
Cash flows from operating activities:
Net loss	$	(405,124)	$	(628,621)
Adjustments to reconcile net loss to net cash used in operating activities:
Amortization of discount on short-term investments	(7,186)		(3,989)
Unrealized foreign exchange loss (gain)	220		(463)
Depreciation	90		62
Stock-based compensation	141,497		489,880


Change in operating assets and liabilities:
Prepaid expenses and other current assets	(23,046)		(81)
Other assets	(1,243)		(3,672)
Accounts payable	2,895		18,287
Accrued liabilities	32,955		6,452
Accrued compensation	(5,482)		(5,407)
Other current liabilities	339		(342)
Other non-current liabilities	(30)		52
Operating lease right-of-use assets and lease liabilities, net	700		(70)
Net cash used in operating activities	(263,415)		(127,912)

Cash flows from investing activities:
Maturities and sales of short-term investments	626,088		311,340
Purchase of short-term investments	(402,276)		—
Purchases of property and equipment	(1,154)		(422)

Net cash provided by investing activities	222,658		310,918

Cash flows from financing activities:

Proceeds from the issuance of common stock under at-the-market offering, net of commissions (3)	227,413		—
Proceeds received related to employee stock purchase plan and exercise of stock options	7,462		2,584
Proceeds from exercise of warrants (3)	—		7,315
Net cash provided by financing activities	234,875		9,899
Effect of exchange rate changes on cash	(18)		99
Increase in cash, cash equivalents and restricted cash	194,100		193,004
Cash, cash equivalents and restricted cash at beginning of period	225,582		105,187
Cash, cash equivalents and restricted cash at end of period	$	419,682	$	298,191





Reconciliation of cash, cash equivalents and restricted cash:
Cash and cash equivalents	$	419,365	$	297,872
Restricted cash	317		319
Total cash, cash equivalents and restricted cash	$	419,682	$	298,191

Supplemental Disclosure of Non-Cash Investing and Financing Activities:

Leased assets obtained in exchange for operating lease liabilities	$	709	$	—
Unpaid amounts related to property and equipment, net	$	—	$	72

(3) Refer to Note 11 – Related Party Transactions.

The accompanying notes are an integral part of the unaudited condensed consolidated financial statements.

Summit Therapeutics Inc.

Notes to Unaudited Condensed Consolidated Financial Statements

(in thousands, except share and per share data)

1. Organization

Summit Therapeutics Inc. (“we”, “Summit” or the “Company”) is a biopharmaceutical company focused on the discovery, development, and commercialization of patient-, physician-, caregiver- and societal-friendly medicinal therapies intended to improve quality of life, increase potential duration of life, and resolve serious unmet medical needs. The Company’s pipeline of product candidates is designed with the goal to become the patient-friendly, new-era standard-of-care medicines, in the therapeutic area of oncology.

The Company’s current lead development candidate is ivonescimab, a novel, potential first-in-class bispecific antibody intending to combine the effects of immunotherapy via a blockade of PD-1 with the anti-angiogenesis effects of an anti-VEGF compound into a single molecule. On December 5, 2022, the Company entered into the License Agreement with Akeso, Inc. and its affiliates (collectively, “Akeso”) pursuant to which the Company has in-licensed intellectual property rights related to ivonescimab (as amended, the “License Agreement”), as further described in Note 4. Through the License Agreement, the Company obtained the rights to develop and commercialize ivonescimab in the United States, Canada, Europe, and Japan. The License Agreement and transaction closed in January 2023 following customary waiting periods. On June 3, 2024, the Company entered into an amendment to the License Agreement (the “Second Amendment”) with Akeso to expand its territories covered under the License Agreement to also include Latin America, including Mexico and all countries in Central America and South America, the Middle East and Africa (collectively, and as expanded, the “Licensed Territory”). The Company’s operations are focused on the development of ivonescimab and other future activities, as the Company determines.

Basis of Presentation

The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States (“U.S. GAAP”) and pursuant to the rules and regulations of the SEC. Accordingly, certain information and disclosures required by U.S. GAAP for complete consolidated financial statements are not included herein. All intercompany accounts and transactions have been eliminated in consolidation. The interim financial data as of June 30, 2026 and for the three and six months ended June 30, 2026 are unaudited; however, in the opinion of management, the interim data includes all adjustments, consisting of normal recurring adjustments, necessary for a fair statement of the results for the interim periods. The condensed consolidated balance sheet presented as of December 31, 2025 has been derived from the consolidated audited financial statements as of that date. The results of the period are not necessarily indicative of full year results or any other interim period. These unaudited interim condensed consolidated financial statements should be read in conjunction with the audited financial statements and notes thereto of the Company which are included in the Company’s Annual Report. The financial results of the Company’s activities are reported in United States Dollars.

Use of Estimates

The preparation of these unaudited condensed consolidated financial statements requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities at the date of the unaudited condensed consolidated financial statements and the reported amounts of income and expenses during the reporting period. On an on-going basis, management evaluates its estimates and judgments, including those related to accrued research and development expenses, stock-based compensation, and income taxes. Management bases its estimates and judgments on historical experience and on various other factors that are believed to be reasonable under the circumstances, the results of which form the basis for making judgments about the carrying values of assets and liabilities that are not readily apparent from other sources. Actual results may differ from these estimates under different assumptions or conditions.

Liquidity and Capital Resources

During the three and six months ended June 30, 2026, the Company incurred a net loss of $215,700 and $405,124, respectively, and cash used in operating activities for the six months ended June 30, 2026 was $263,415. As of June 30, 2026,

Summit Therapeutics Inc.

Notes to Unaudited Condensed Consolidated Financial Statements

(in thousands, except share and per share data)

the Company had an accumulated deficit of $2,699,283, cash and cash equivalents of $419,365 and short-term investments of $271,313. The Company expects to continue to generate operating losses for the foreseeable future.

The Company’s cash and cash equivalents and short-term investments are not sufficient to fund the Company’s planned operations for a period of at least one year from the date these unaudited condensed consolidated financial statements are issued.

Until the Company can generate substantial revenue and achieve profitability, the Company will need to raise additional capital to fund its ongoing operations and capital needs. The Company continues to evaluate options to further finance its operating cash needs for its product candidates through a combination of some, or all, of the following: equity and debt offerings, collaborations, strategic alliances, grants and clinical trial support from government entities, philanthropic, non-government and not-for-profit organizations, and marketing, distribution or licensing arrangements. There is no assurance, however, that additional financing will be available when needed or that management of the Company will be able to obtain financing on terms acceptable to the Company. If the Company is unable to obtain funding when required in the future, the Company could be required to delay, reduce, or eliminate research and development programs, product portfolio expansion, or future commercialization efforts, which could adversely affect its business prospects. These conditions raise substantial doubt about the Company’s ability to continue as a going concern.

The accompanying unaudited condensed consolidated financial statements have been prepared assuming the Company will continue as a going concern, which contemplates the realization of assets and satisfaction of liabilities in the normal course of the business. The unaudited condensed consolidated financial statements do not include any adjustments relating to the recoverability and classification of recorded asset amounts or the amounts and classifications of liabilities that might result from the outcome of this uncertainty.

2. Summary of Significant Accounting Policies and Recent Accounting Pronouncements

Significant Accounting Policies

There have been no significant changes to the Company’s significant accounting policies used in the preparation of these unaudited condensed consolidated financial statements for the six months ended June 30, 2026 as compared with those discussed in Note 2 to the consolidated financial statements in the Company’s Annual Report.

Recently Issued Accounting Pronouncements

In November 2024, the FASB issued ASU 2024-03, Disaggregation of Income Statement Expenses (“ASU 2024-03”) which requires disclosures about specific types of expenses included in the expense captions presented on the face of the income statement as well as disclosures. The guidance is to be applied prospectively, with the option for retrospective application and is effective for public business entities for fiscal years beginning after December 15, 2026, and interim periods beginning after December 15, 2027. Early adoption is permitted. The Company is currently evaluating the impact of the adoption of this standard on the Company’s consolidated financial statements and related disclosures.

In December 2025, the FASB issued ASU 2025-11, “Narrow-Scope Improvements”, which is intended to improve the navigability of the guidance in ASC 270 and clarify when the guidance is applicable. ASU 2025-11 is effective for interim reporting periods within annual reporting periods beginning after December 15, 2027. Early adoption is permitted. The Company is currently evaluating the impact of the adoption of this standard on the Company’s consolidated financial statements and related disclosures.

Other recent authoritative guidance issued by the FASB (including technical corrections to the FASB ASC), the American Institute of Certified Public Accountants, and the SEC did not or are not expected to have a material impact on the Company’s consolidated financial statements and related disclosures.

Summit Therapeutics Inc.

Notes to Unaudited Condensed Consolidated Financial Statements

(in thousands, except share and per share data)

3. Segment Reporting

The Company’s chief operating decision makers (the “CODM function”), which are the Company’s Co-Chief Executive Officers, Mr. Duggan and Dr. Zanganeh, and Chief Operating Officer and Chief Financial Officer, Mr. Soni, utilize consolidated net loss that is reported on the unaudited condensed consolidated statement of operations and comprehensive loss to make decisions about allocating resources and assessing performance for the entire Company. The CODM function approves key operating and strategic decisions, including key decisions in clinical development and clinical operating activities, entering into significant contracts, such as revenue contracts and collaboration agreements and approves the Company’s consolidated operating budget. The CODM function views the Company’s operations and manages its business on a consolidated basis and as a single reportable operating segment. The CODM function is regularly provided with the following significant segment expenses:


	Three Months Ended June 30,				Six Months Ended June 30,
	2026		2025		2026		2025
Oncology clinical trial related costs	$	114,339	$	67,824	$	204,534	$	104,187

Compensation related costs, excluding stock-based compensation	27,996		16,800		54,428		32,654
Stock-based compensation	68,706		478,784		141,497		489,880
Other expenses (1)	9,455		5,029		15,249		8,567
Total segment expenses	220,496		568,437		415,708		635,288
Other income, net	4,796		2,729		10,584		6,667

Net loss	$	(215,700)	$	(565,708)	$	(405,124)	$	(628,621)

(1) Other expenses include general and administrative expenses excluding compensation and stock-based compensation.

As of June 30, 2026 and December 31, 2025, substantially all of the Company’s long-lived assets are located in the United States.

4. Akeso License and Collaboration Agreement

On December 5, 2022, the Company entered into the License Agreement with Akeso pursuant to which the Company is in-licensing its breakthrough bispecific antibody, ivonescimab. The License Agreement and transaction closed in January 2023 following customary waiting periods.

Ivonescimab, known as AK112 in China and Australia, and also as SMT112 in the Summit Licensed Territory, is a novel, potential first-in-class bispecific antibody intending to combine the effect of immunotherapy via a blockade of PD-1 with the anti-angiogenesis effects of an anti-VEGF into a single molecule. Ivonescimab was engineered to bring two well established oncology targeted mechanisms together. Ivonescimab is currently in clinical development and, pursuant to the terms of the License Agreement, Summit will design and conduct the clinical trial activities to support regulatory filings in the Licensed Territory that Summit will submit.

Pursuant to the terms of the License Agreement, Summit will have final decision-making authority with respect to clinical development strategy and execution in the Licensed Territory. For co-joined studies in which both Summit and Akeso participate, mutual agreement is required for material decisions; Summit retains the exclusive decision making with respect to participating in, and continuing its participation in, co-joined studies in the Licensed Territory. Pursuant to the terms of the License Agreement, Summit will have final decision-making authority with respect to commercial strategy, pricing and reimbursement and other commercialization matters in the Licensed Territory. In connection with the License Agreement, the Company agreed to purchase a certain portion of drug substance and/or drug product for clinical and commercial supply and to enter into a supply agreement with Akeso. Summit is not assuming any liabilities (including contingent liabilities), acquiring any physical assets or trade names, or hiring or acquiring any employees from Akeso in connection with the

Summit Therapeutics Inc.

Notes to Unaudited Condensed Consolidated Financial Statements

(in thousands, except share and per share data)

License Agreement. Through the License Agreement, the Company obtained the rights to develop and commercialize ivonescimab in the United States, Canada, Europe, and Japan.

In exchange for the rights obtained, the Company made an upfront payment of $500,000 to Akeso, of which $274,900 was paid in cash and, pursuant to the License Agreement and Issuance Agreement, Akeso elected to receive 10,000,000 shares of the Company’s common stock, par value $0.01 per share (“common stock”) in lieu of $25,100 in cash. The remaining $200,000 amount of the upfront payment was paid on March 6, 2023.

Effective June 3, 2024, the Company and Akeso entered into the Second Amendment to the License Agreement to expand the Company’s territories covered under the License Agreement to include the Latin America, Middle East and Africa regions. Pursuant to the Second Amendment, the Company paid an upfront payment to Akeso of $15,000 in the third quarter of 2024. Akeso will also be eligible to receive up to an additional $55,000 upon the achievement of certain commercial milestones. Except as specifically modified by the Second Amendment, the terms and conditions of the License Agreement remain in full force and effect.

The Company has accounted for the License Agreement and Second Amendment to acquire the rights to develop and commercialize ivonescimab as the acquisition of an asset. All of the consideration relates to ivonescimab and technological feasibility of the asset has not yet been established since ivonescimab is in clinical development. As such, the Company has expensed the consideration as acquired in-process research and development upon closing of the transaction in the unaudited condensed consolidated statement of operations and comprehensive loss. There was no acquired in-process research and development expense for the three and six months ended June 30, 2026 and 2025, respectively. In addition to the payments already made to Akeso, under the License Agreement and Second Amendment, there are additional potential milestone payments of up to $4,555,000, as Akeso will be eligible to receive regulatory milestones of up to $1,050,000 and commercial milestones of up to $3,505,000. In addition, Akeso will be eligible to receive low double-digit royalties on net sales.

5. Other Income, Net

The following table sets forth the components of other income, net:


	Three Months Ended June 30,			Six Months Ended June 30,
		2026		2025		2026		2025
Foreign currency (loss) gain		$	(90)	$	(199)	$	(152)	$	(122)
Investment income (1)		4,386		2,981		10,236		6,842
Other (2)		500		(53)		500		(53)
Total		$	4,796	$	2,729	$	10,584	$	6,667

(1) Investment income relates to the Company’s money market funds, certificate of deposit and U.S. government treasury bills. Refer to Note 7 for details.

(2) In June 2026, the Company entered into an asset purchase agreement (the “APA”) with a third party. Pursuant to the APA, the Company sold the asset relating to the pharmaceutical compound known as ridinilazole. In consideration for such assignment of rights, the third party has made an upfront non-refundable payment to the Company of $0.5 million. Additionally, the third party has also agreed to make additional payments totaling $1.5 million that are contingent upon the achievement of certain regulatory milestones, sales-based milestone payments of up to $103 million, as well as quarterly royalty payments that are based on a single digit percentage of net sales for certain products covered by the assigned and transferred patent rights. The Company did not have any amounts capitalized related to the underlying portfolio of patents, nor was any write-down of assets recorded upon executing the APA. The Company received the payment of $0.5 million from the third party in June 2026 and recognized the $0.5 million within other income, net on the condensed consolidated statements of operations and comprehensive loss for the three and six months ended June 30, 2026. The Company does not have any ongoing obligations associated with the APA. As of June 30, 2026, the Company is unable to estimate the timing or

Summit Therapeutics Inc.

Notes to Unaudited Condensed Consolidated Financial Statements

(in thousands, except share and per share data)

likelihood of achieving the regulatory milestone payments, sales-based milestone payments, and the quarterly royalty payments.

6. Net Loss per Share

The following table sets forth the computation of basic and diluted net loss per share:


	Three Months Ended June 30,				Six Months Ended June 30,
	2026		2025		2026		2025
Net loss	$	(215,700)	$	(565,708)	$	(405,124)	$	(628,621)

Basic and diluted weighted average number of shares of common stock outstanding	778,184,568		742,615,007		776,824,812		740,358,044



Basic net loss per share	$	(0.28)	$	(0.76)	$	(0.52)	$	(0.85)
Diluted net loss per share	$	(0.28)	$	(0.76)	$	(0.52)	$	(0.85)

Basic net loss per share is computed by dividing the net loss by the weighted-average number of common shares outstanding for the period. Diluted net loss per share is computed by dividing the diluted net loss by the weighted-average number of common shares outstanding for the period, including potentially dilutive common shares. Since the Company was in a loss position for all periods presented, basic net loss per share is the same as diluted net loss per share for all periods, as the inclusion of all potential common share equivalents outstanding would have been anti-dilutive.

The following potentially dilutive securities were excluded from the computation of the diluted net loss per share of common stock for the periods presented because their effect would have been anti-dilutive:


	June 30,
	2026	2025
Options to purchase common stock	118,267,815	114,506,229
Restricted stock units	730,000	—
Shares expected to be purchased under employee stock purchase plan	113,419	66,324

Total	119,111,234	114,572,553

Stock options that are outstanding and contain improbable vesting criteria are excluded from the presentation of common stock equivalents outstanding in the table above.

Summit Therapeutics Inc.

Notes to Unaudited Condensed Consolidated Financial Statements

(in thousands, except share and per share data)

7. Fair Value Measurements and Short-Term Investments

The following tables set forth the Company’s fair value hierarchy for its assets and liabilities that are measured at fair value on a recurring basis as of June 30, 2026 and December 31, 2025:


		June 30, 2026
	Fair Value Hierarchy Level	Amortized Cost		Unrealized Gain		Unrealized (Loss)		Credit (Loss)		Fair Value
Financial assets included within cash and cash equivalents:
Money market funds	Level 1	$	184,354	$	—	$	—	$	—	$	184,354
U.S. Government treasury bills	Level 2	150,114		—		—		—		150,114
Financial assets included within short-term investments:

U.S. Government treasury bills	Level 2	271,384		—		(71)		—		271,313
Total		$	605,852	$	—	$	(71)	$	—	$	605,781


		December 31, 2025
	Fair Value Hierarchy Level	Amortized Cost		Unrealized Gain		Unrealized (Loss)		Credit (Loss)		Fair Value
Financial assets included within cash and cash equivalents:
Money market funds	Level 1	$	163,588	$	—	$	—	$	—	$	163,588
U.S. Government treasury bills	Level 2	45,300		12		—		—		45,312
Financial assets included within short-term investments:
Certificate of deposit	Level 2	25,000		—		—		—		25,000
U.S. Government treasury bills	Level 2	463,022		160		—		—		463,182
Total		$	696,910	$	172	$	—	$	—	$	697,082

The tables above do not include cash at June 30, 2026 and December 31, 2025 of $84,897 and $16,366, respectively.

The Company believes that the carrying amounts of prepaid expenses and other current assets, accounts payable, and accrued liabilities approximate their fair values due to the short-term nature of those instruments.

Realized gain (loss) on short-term investments for the three and six months ended June 30, 2026 and 2025 were de minimis, respectively.

8. Research and Development Prepaid Expenses and Accrued Liabilities

Included within prepaid expenses and other current assets at June 30, 2026 and December 31, 2025 is $24,318 and $3,996, respectively, of prepayments relating to research and development expenditures. Included within accrued liabilities at June 30, 2026 and December 31, 2025 is $63,379 and $31,498, respectively, relating to research and development expenditures.

These amounts are determined based on the estimated costs to complete each study or activity related to the ongoing clinical trials for ivonescimab, the estimation of the current stage of completion and the invoices received, as well as predetermined milestones which are not reflective of the current stage of development for prepaid expenses. However, accrued liabilities

Summit Therapeutics Inc.

Notes to Unaudited Condensed Consolidated Financial Statements

(in thousands, except share and per share data)

increase as the activities progress. The key sensitivity is the estimated current stage of completion of each study or activity, which is based on information received from the supplier and the Company’s operational knowledge of the work completed under those contracts.

9. Stockholders' Equity

Preferred Stock

As of June 30, 2026 and December 31, 2025, the Company had 20,000,000 shares of preferred stock, par value $0.01, authorized and no shares issued and outstanding.

Common Stock

As of June 30, 2026 and December 31, 2025, the Company had authorized 1,000,000,000 shares of common stock.

October 2025 Private Investment in Public Equity (PIPE)

On October 21, 2025, the Company entered into securities purchase agreements (the “October 2025 Purchase Agreements”) with multiple biotech institutional investors and individual accredited investors, for the sale by the Company in a private placement for an aggregate of 26,682,846 shares of the Company’s common stock, par value $0.01 per share of common stock, at purchase price of $18.74 per share, which was the closing price of the common stock on October 21, 2025, for aggregate gross proceeds to the Company of approximately $500,037, with immaterial offering costs. The private placement transaction was completed in October 2025.

All of the Company's Section 16 officers participated in the capital raise. The Company’s Co-CEO, Executive Chairman and majority stockholder, its Co-CEO and the President and member of the Board, its COO, CFO, and member of the Board, its CAO, and certain non-executive employees and other related persons purchased an aggregate of 14,514,402 shares of common stock for gross proceeds of approximately $272,000. Additionally, Akeso purchased 533,617 shares of common stock for gross proceeds of approximately $10,000. The remaining $218,037 was raised with multiple leading biotech institutional investors.

The October 2025 Purchase Agreements contain customary representations, warranties and covenants by the Company, customary indemnification obligations of the Company, including for liabilities under the Securities Act, as amended (the “Securities Act”), other obligations of the parties and termination provisions. The representations, warranties and covenants contained in the October 2025 Purchase Agreements were made only for purposes of the October 2025 Purchase Agreements and as of specific dates, were solely for the benefit of the parties to such agreements and were subject to limitations agreed upon by the contracting parties.

On October 21, 2025, in connection with the October 2025 Purchase Agreements, the Company entered into Registration Rights Agreements with the Investors (the “October 2025 Registration Rights Agreements”). The October 2025 Registration Rights Agreements provide, among other things, that the Company will as soon as reasonably practicable, and in any event by no later than December 19, 2025, file with the SEC a registration statement registering the resale of the shares. The Company filed the registration statement on October 29, 2025, which was automatically effective upon filing.

At-the-Market Offering (ATM Offering)

On May 13, 2024, the Company entered into an at-the-market (“ATM”) sales agreement (the “Original Distribution Agreement”) pursuant to which the Company may, subject to the terms and conditions set forth in the agreement offer and sell, from time to time, through or to the agents, acting as agents or principal, shares of the Company’s common stock, par value $0.01, having an aggregate offering price of up to $90,000. On August 11, 2025, the Company entered into an amendment (the “Amendment”) to the Original Distribution Agreement (as amended, the “Distribution Agreement”), which among other things, increased the aggregate offering price of common stock that the Company may offer and sell from time to time through the sales agent under the Distribution Agreement by an additional $360,000.

Summit Therapeutics Inc.

Notes to Unaudited Condensed Consolidated Financial Statements

(in thousands, except share and per share data)

From the date of the Original Distribution Agreement through June 30, 2026, the Company sold 23,578,867 shares of common stock under the ATM at a weighted-average price of $16.18 per share, for gross proceeds of $381,597, with commissions and fees of approximately $6,623. The remaining gross proceeds available under the Distribution Agreement as of June 30, 2026 were approximately $68,403 which was utilized subsequent to June 30, 2026. The Company plans to use the net proceeds from this offering for working capital and general corporate purposes.

Warrants

As of June 30, 2026 and December 31, 2025, the Company had no outstanding warrants. During the three and six months ended June 30, 2025, warrants of 1,048,834 and 4,629,988 respectively with a weighted average exercise price of $1.58 were exercised.

10. Stock-Based Compensation

2020 Stock Award Plan

The Company currently grants stock options and restricted stock units to employees and directors under the 2020 Stock Incentive Plan (the “2020 Plan”) and formerly, the Company granted stock options under the 2016 Long Term Incentive Plan. The 2020 Plan is administered by the Compensation Committee of the Company’s Board of Directors. The 2020 Plan is intended to attract and retain employees and directors and provide an incentive for these individuals to assist the Company to achieve long-range performance goals and to enable these individuals to participate in the long-term growth of the Company.

Based on the provisions of the 2020 Plan, the number of shares of common stock available for issuance under the 2020 Plan increased by 6,400,000 shares on January 1, 2026. On September 18, 2025, the Board approved an increase of 8,000,000 shares of common stock available for issuance under the 2020 Plan (the “Incremental Pool”), which was approved by the majority of the shares voting at the Company’s Annual Meeting of Stockholders on June 10, 2026. As of June 30, 2026, there were 11,470,313 shares available for grant under the 2020 Plan.

On May 3, 2024, the Board adopted the 2024 Inducement Pool (the “Inducement Pool”), which mirrors the terms of the 2020 Plan, with a total of 2,000,000 shares of common stock reserved for issuance under the Inducement Pool. Effective January 22, 2025, the number of shares of common stock available under the Inducement Pool increased by 2,000,000 shares. The Inducement Pool provides for the grant of non-qualified stock options and was approved by the Compensation Committee of the Board without stockholder approval pursuant to Rule 5635(c)(4) of the Nasdaq Listing Rules. As of June 30, 2026, there were 1,707,478 shares available for grant under the Inducement Pool.

Summit Therapeutics Inc.

Notes to Unaudited Condensed Consolidated Financial Statements

(in thousands, except share and per share data)

Stock Options

The following table summarizes the Company’s stock option activity for the six months ended June 30, 2026.


	Number of Options	Weighted average exercise price		Weighted average remaining contractual term (years)
Outstanding at December 31, 2025	119,464,728	$	4.14	7.8
Granted	5,092,636	17.15
Forfeited	(4,938,700)	9.69
Exercised	(1,250,849)	5.22
Outstanding at June 30, 2026	118,367,815	$	4.45	7.4
Vested and expected to vest as of June 30, 2026	113,153,918	$	4.35	7.3
Exercisable at June 30, 2026	67,128,849	$	2.76	7.0

Restricted Stock Units