Summit Therapeutics Inc

UNITED STATES SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 10-K

(Mark One)

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

For the fiscal year ended December 31, 2023

or

☐ 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

(Exact Name of Registrant as Specified in its Charter)

(650)460-8308

(Registrant’s Telephone Number, Including Area Code)

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

Securities registered pursuant to Section 12(g) of the Act: None

Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act. Yes ☐No ☒

Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Act. Yes ☐No ☒

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 posted 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.

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 has filed a report on and attestation to its management’s assessment of the effectiveness of its internal control over financial reporting under Section 404(b) of the Sarbanes-Oxley Act (15 U.S.C. 7262(b)) by the registered public accounting firm that prepared or issued its audit report.☐

If securities are registered pursuant to Section 12(b) of the Act, indicate by check mark whether the financial statements of the registrant included in the filing reflect the correction of an error to previously issued financial statements.

Indicate by check mark whether any of those error corrections are restatements that required a recovery analysis of incentive-based compensation received by any of the registrant’s executive officers during the relevant recovery period pursuant to §240.10D-1(b).

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

The aggregate market value of the voting common stock held by non-affiliates based on the closing stock price on June 30, 2023, was $108.4 million. For purposes of this computation only, all executive officers and directors have been deemed affiliates.

The number of outstanding shares of the registrant’s common stock, par value $0.01 per share, as of February 9, 2024 was 701,697,179.

TABLE OF CONTENTS

CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS

This Annual Report on Form 10-K contains “forward-looking statements” within the meaning of the Private Securities Litigation Reform Act of 1995, Section 27A of the Securities Act of 1933 and Section 21E of the Securities Exchange Act of 1934 regarding the future financial performance, business prospects and growth of Summit Therapeutics Inc., that involve substantial risks and uncertainties. All statements contained in this Annual Report on Form 10-K, 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 Annual Report on Form 10-K include, among other things, statements about:

•the ability to develop a successful product candidate under the License Agreement (as defined in Item I Business, Overview);

•our ability to raise sufficient additional funds to make payments under the License Agreement;

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

•the timing and conduct of clinical trials for any product candidates;

•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 for our product candidates;

•our sales, marketing and distribution capabilities and strategy;

•our ability to establish and maintain arrangements for manufacture of our product candidates;

•our intellectual property position;

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

•the impact of government laws and regulations;

•our competitive position;

•the need to raise additional capital to fund ongoing operations and capital needs; and

•the impact of public health epidemics, such as the novel coronavirus pandemic (“COVID-19”), the response to such epidemics and the potential effects of such epidemics on our business, financial results, supply chain and market.

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 Report, particularly in the “Risk Factors” in Part 1, Item 1A of this Annual Report on Form 10-K, 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 Annual Report on Form 10-K and the documents that we have filed as exhibits to this Annual Report on Form 10-K 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.

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Summary

Below is a summary of the principal factors that make an investment in Summit Therapeutics Inc. speculative or risky. The following summary does not contain all of the information that may be important to you, and you should read the below summary in conjunction with the more detailed discussion of risks set forth under the heading “Risk Factors” in Part I, Item IA of this Annual Report on Form 10-K.

Risks Related to Our Financial Position and Need for Additional Capital

•We presently do not have sufficient working capital to fund our operations for the next twelve months, which raises substantial doubt of our ability to continue as a going concern.

•We will need to obtain additional funding to finance our operations and complete the development and any commercialization of our investigational products. If we do not receive substantial capital when needed, we may be forced to restrict our operations or delay, reduce or eliminate our product development programs.

•We depend heavily on the success of ivonescimab. If we are unable to successfully develop and commercialize ivonescimab, or experience significant delays in doing so, we may extend the period in which we will incur significant financial losses as an organization.

•We are a development-stage company and have incurred significant losses since our inception. We anticipate that we will continue to incur losses for at least the next several years and may never generate profits from operations or maintain profitability.

•We will need substantial additional capital to fund our operations and to make payments under the License Agreement and the Note Purchase Agreement and if we fail to obtain necessary financing, we could be forced to delay, reduce or eliminate the development and commercialization of our product candidates.

•We will need to raise additional capital which may result in further dilution to our investors and additional indebtedness. The servicing of debt may impair our liquidity position.

Risks Related to the Development and Commercialization of our Product Candidates

•We can provide no assurance that our clinical product candidates, including our lead product candidate, ivonescimab, will obtain regulatory approval or that the results of clinical studies will be favorable.

•Drug discovery and development is a complex, time-consuming and expensive process that is fraught with risk and a high rate of failure.

•If we experience delays or difficulties in the enrollment of patients in our clinical trials, our receipt of necessary marketing approvals could be delayed or prevented.

•Regulatory requirements and timelines may affect the scope and timeline of our trials and the potential market for our product candidates.

•If we experience any number of possible unforeseen events in connection with our clinical trials, potential marketing approval or commercialization of our product candidates could be delayed or prevented.

•If serious adverse or inappropriate side effects are identified during the development of ivonescimab or any other product candidate, we may need to abandon or limit our development of that product candidate.

•If clinical trials of our product candidates fail to demonstrate safety and efficacy to the satisfaction of the U.S. Food and Drug Administration, or the FDA, or the European Medicines Agency, or the EMA, or do not otherwise produce favorable results, we may incur additional costs or experience delays in completing, or ultimately be unable to complete, the development and commercialization of ivonescimab or any other product candidate.

•Biologics, such as ivonescimab, carry unique risks and uncertainties, which could have a negative impact on our business.

•Use of third parties, including Akeso, to manufacture our product candidates may increase the risk that we will not have sufficient quantities of our product candidates or products or such quantities at an acceptable time and cost, which could delay, prevent or impair our development or commercialization efforts,

•If our manufacturing partners for the supply of ivonescimab or other product candidates divert their supply of materials needed for our product candidates to larger pharmaceutical companies, our ability to complete our clinical trials or eventually bring our product candidates to market may be compromised.

•We have not yet developed, and may never successfully develop, any marketed drugs.

•Regulatory requirements and timelines may affect the scope and timeline of our trials and the potential market for our product candidates.

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Risks Related to our Financial and Intellectual Property Dependencies on Third Parties

•We depend on our relationship with, and the comprehensiveness of the intellectual property licensed from Akeso, and termination of the License Agreement, any of the licenses under the License Agreement, or issues as to intellectual property could have a material adverse effect on our business.

•We depend on collaborations with third parties for the development and commercialization of some of our product candidates. If those collaborations are not successful, we may not be able to capitalize on the market potential of these product candidates.

Risks Related to Our Industry and Market

•We face substantial competition, which may result in others discovering, developing or commercializing products before us or more successfully than we do.

•We may pursue business development opportunities to expand or enhance our pipeline of drug candidates, including without limitation, through potential acquisitions of and/or collaborations with other entities, that may not achieve intended results or could increase the number of our outstanding shares or amount of outstanding debt or result in a change of control.

Legal, Tax, Regulatory and Compliance Risks

•Our ability to commercialize any of our product candidates is subject to substantial regulatory and legislative uncertainty, including as to pricing, reimbursement practices or other healthcare initiatives which could harm our business.

•Our business is subject to the risks associated with doing business in China.

•We may face costly legal claims, in particular related to product liability and intellectual property infringement.

•We are subject to certain United States (“U.S.”), United Kingdom (“U.K.”) and foreign anti-corruption, anti-money laundering, export control, sanctions and other trade laws and regulations. We can face serious consequences for violations.

Risks Related to Our Intellectual Property, Cybersecurity and Data Privacy

•We rely upon patents to protect our technology. We may be unable to protect our intellectual property rights and we may be liable for infringing the intellectual property rights of others.

•Our actual or perceived failure to comply with stringent and changing obligations related to data privacy and security could lead to regulatory investigations and actions, litigation, fines and penalties, disruptions to our business operations, reputational harm, loss of revenue and profits and other adverse business impacts.

•We are exposed to risks related to cybersecurity and data privacy threats and incidents and we are subject to restrictions and changes in laws and regulations governing our data privacy and data protection, any of which could have a material adverse affect on our business.

Risks Related to Corporate Governance and Employee Relations

•Our future success depends on our ability to retain our Chairman and Chief Executive Officer, our Chief Executive Officer, President and member of the Board, our Chief Operating Officer and a member of the Board, and other key executives and to attract, retain and motivate qualified personnel.

•Our Chairman and Chief Executive Officer owns more than a majority of the voting power of the outstanding shares of our common stock, and as a result investors may have limited ability to affect either the corporate governance of the Company or the taking of certain major decisions.

Risks Related to Owning Our Common Stock

•Substantial future sales of our shares of common stock in the public market, or the perception that these sales could occur, could cause the price of the shares to decline significantly, even if our business is doing well.

•The prices of our shares of common stock may be volatile and fluctuate substantially, which could result in substantial losses for our stockholders.

Risks Related to Widespread Health Concerns

•Widespread health concerns, including COVID-19 and their enduring impact on our business remains uncertain. Our business has and could continue to be adversely affected, directly or indirectly, by any pandemic and other health concerns that may arise.

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