Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations

You should read the following discussion and analysis of our financial condition and results of operations together with our consolidated financial statements and related notes appearing elsewhere in this Annual Report on Form 10-K. Some of the information contained in this discussion and analysis or set forth elsewhere in this Annual Report on Form 10-K, including information with respect to our plans and strategy for our business and related financing, includes forward-looking statements that involve risks and uncertainties. As a result of many factors, including those factors set forth in “Item 1A. Risk Factors” of this Annual Report on Form 10-K, our actual results could differ materially from the results described in or implied by the forward-looking statements contained in the following discussion and analysis.

The Management’s Discussion and Analysis of Financial Condition and Results of Operations, or MD&A, describes principal factors affecting the results of our operations, financial condition and liquidity, as well as our critical accounting policies and estimates that require significant judgment and thus have the most significant potential impact on our Consolidated Financial Statements. This section provides an analysis of our financial results for the year ended December 31, 2023 compared to the same period in the prior year.

Company Overview

We are 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. Our 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.

Our 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, we entered into a Collaboration and License Agreement (the “License Agreement”) with Akeso, Inc. and its affiliates (“Akeso”) pursuant to which the Company has in-licensed ivonescimab. Through the License Agreement, we obtained the rights to develop and commercialize ivonescimab in the United States, Canada, Europe, and Japan (the “Licensed Territory”). The License Agreement and transaction closed in January 2023 following customary waiting periods. Our operations will be focused on the development of ivonescimab and other future activities, as the Company determines.

We have begun our development for ivonescimab in non-small cell lung cancer (“NSCLC”), specifically launching Phase III clinical trials in the following indications:

a) ivonescimab combined with chemotherapy in patients with epidermal growth factor receptor (“EGFR”)-mutated, locally advanced or metastatic non-squamous NSCLC who have progressed after treatment with a third-generation EGFR tyrosine kinase inhibitor (“TKI”) (“HARMONi”); and

b) ivonescimab combined with chemotherapy in first-line metastatic squamous NSCLC patients (“HARMONi-3”)

As of the date of these financial statements, both studies are enrolling patients.

The entry into the License Agreement with Akeso represents a significant change in our strategy and its future operations will be focused on the development of ivonescimab and other future activities as the Company determines. Our portfolio includes ridinilazole, a product candidate for treating patients suffering from Clostridioides difficile infection, also known as C. difficile infection, or CDI. All prior development and marketing activities related to ridinilazole have been terminated. Our anti-infectives portfolio includes SMT-738, the first of a novel class of precision antibiotics for combating multidrug resistant infections, specifically carbapenem-resistant Enterobacteriaceae (“CRE”) infections. We will continue to pursue partnerships for further development of SMT-738.

Key Components of our Results of Operations

Revenue

Revenue consists of amounts received from the license and commercialization agreement with Eurofarma Laboratórios S.A. (“Eurofarma”). We have not generated any revenue from product sales.

Under the terms of the license and commercialization agreement with Eurofarma, we received an upfront payment of $2.5 million in December 2017. In February 2020, we achieved the first enrollment milestone and received $1.0 million. In September 2021, we achieved the second enrollment milestone and received $1.3 million. The terms of the contract have been assessed under ASC 606 and currently only the upfront payment and the first two milestone payments are included in the transaction price. These payments were initially reported as deferred revenue in the balance sheet and were recognized as revenue ratably over the determined performance period.

There was no revenue recognized for the year ended December 31, 2023. Revenue recognized during the year ended December 31, 2022 related to the upfront payment and the first two enrollment milestones earned in accordance with our revenue

recognition policy. The revenue was recognized ratably over the determined performance period to reflect the transfer of control to the customer occurring over the time period that the research and development services were provided. This output method is, in management’s judgment, the best measure of progress towards satisfying the performance period.

Other Operating Income

Other operating income includes income received and recognized from grants and clinical trial support from government entities, philanthropic, non-government and not-for-profit organizations.

In September 2017, we were awarded a contract from the Biomedical Advanced Research and Development Authority (“BARDA”), part of the Office of the Assistant Secretary for Preparedness and Response at the United States Department of Health and Human Services, to fund, in part, the clinical and regulatory development of ridinilazole for the treatment of infections caused by C. difficile. The contract provides for a cost-sharing arrangement under which BARDA funded a specified portion of estimated costs for the continued clinical and regulatory development of ridinilazole for CDI. Under this cost sharing arrangement, we were responsible for a portion of the costs associated with each segment of work, including any costs in excess of the estimated amounts. The awarded contract, as amended in 2019 and 2020, provided for total award up to $72.5 million, and total amount of committed funding to $62.4 million. As of December 31, 2023, based on translation of historical foreign currency amounts in the period, the Company has recognized $59.2 million of cumulative income since contract inception.

The remaining federal government funding is dependent on BARDA in its sole discretion exercising the final independent option work segment, upon the achievement by the Company of certain agreed-upon milestones for ridinilazole. This option work segment was never exercised by BARDA. The contract ran through April 2022 and was extended through December 2022 as a no cost contract, solely to close out open activities. As of December 31, 2023, based on translation of historical foreign currency amounts in the period, an aggregate of $59.2 million of cumulative income has been recognized since contract inception. As a result of our decision to not pursue further internal clinical development of ridinilazole and seek partners or a divestiture related to ridinilazole as a path forward for the clinical development of the asset, we recognized the remainder of the deferred income for BARDA during the third quarter of 2022.

We have also received income from research and development (“R&D”) tax credits, which consist of the R&D tax credit received in the United Kingdom (“U.K.”). We benefit from two U.K. research and development tax credit cash rebate regimes: Small and Medium Enterprise Program (“SME Program”) and the Research and Development Expenditure Credit Program (“RDEC Program”). Qualifying expenditures largely comprise employment costs for research staff, consumables, a proportion of relevant, permitted sub-contract costs and certain internal overhead costs incurred as part of research projects for which we do not receive income. Tax credits related to the SME Program and RDEC Program are recorded as other operating income in the consolidated statements of operations and other comprehensive loss. Under both schemes, we receive cash payments that are not dependent on our pre-tax net income levels.

Based on criteria established by His Majesty’s Revenue and Customs (“HMRC”), a portion of expenditures being carried out in relation to our pipeline research and development, clinical trials management and third-party manufacturing development activities are eligible for the SME regime and we expect such elements of research and development expenditure incurred in our UK entities will also continue to be eligible for the SME regime for future periods.

In May 2021, we started development of a new preclinical candidate, SMT-738, for development in the fight against multi-drug resistant infections, specifically Carbapenem-resistant Enterobacteriaceae (“CRE”) infections. Simultaneously, we received an award from the Trustees of Boston University under the Combating Antibiotic Resistant Bacteria Biopharmaceutical Accelerator program (“CARB-X”) to progress this candidate through preclinical development and Phase Ia clinical trials. The award committed initial funding of up to $4.1 million with the possibility of up to another $3.7 million based on the achievement of future milestones. As of December 31, 2023, based on translation of historical foreign currency amounts in the period, $2.9 million of cumulative income has been recognized since contract inception. During the quarter ended September 30, 2022, CARB-X announced changes to its funding arrangements and terms and conditions. As a result, the current arrangement concluded as of June 30, 2022, however we have the ability to recognize reimbursements for any milestone payments related to work incurred subsequent to this date in accordance with this agreement.

Operating Expenses

The majority of our operating expenses since inception have consisted of research and development activities and general and administrative costs.

Research and Development Expenses

Research and development expenses consist of all costs associated with our research and development activities.

These include:

•costs incurred in conducting our preclinical studies and clinical trials through contract research and development organizations, including, but not limited to, preclinical toxicology, pharmacology, formulation and manufacturing work, as well as regulatory, operational, drug supply and treatment costs related to conducting the study;

•laboratory and vendor expenses incurred in relation to our preclinical, non-clinical and clinical studies;

•costs incurred in supply chain development and scale up activities to support product registration;

•employee related expenses, which include salary, benefits and stock-based compensation, for our research and development staff;

•costs incurred in development and conduct of training and education related our development candidates; and

•facilities, depreciation and other expenses, which include direct and allocated expenses for rent and maintenance of facilities, insurance and other supplies.

We utilize our employee and infrastructure resources across multiple research projects. We track expenses related to our clinical programs and certain preclinical programs on a per project basis. We expect our research and development expenses to continue to be significant as we initiate our planned clinical trials of ivonescimab, and continue our activities to initiate preclinical programs for future product candidates. The timing and amount of these expenses will depend upon the outcome of our clinical trials and the associated costs. The timing and amount of these expenses will also depend on the costs associated with potential future clinical trials of our product candidates and the related expansion of our research and development organization, regulatory requirements, advancement of our preclinical programs and product candidate manufacturing costs.

General and Administrative Expenses

General and administrative expenses consist primarily of salaries and benefits related to our executive, finance, business development, human resources and other support functions. Other general and administrative expenses include stock-based compensation expenses, market research costs, facility-related costs, consulting costs and expenses associated with the requirements of being a publicly traded company in the United States, including insurance, legal, audit and taxation services fees.

We anticipate that our general and administrative expenses will continue to increase in the future as we increase our headcount to support our planned clinical trials of ivonescimab, continued research and development and potential commercialization of our product candidates. We also anticipate continued accounting, audit, regulatory, compliance, insurance and investor and public relations expenses associated with being a publicly traded company in the United States.

Other expense, net

Other expense, net primarily consists of foreign currency net gains and losses, cash and imputed interest expense incurred related to our promissory notes to related parties and investment income related to investments in money market funds and U.S. treasury securities.

Imputed interest is calculated as the difference between the expected interest payable and the deemed market rate of interest and is recorded as a debt discount at inception of the note payable with a credit to additional paid-in capital for notes payable to related parties. The debt discount is amortized to interest expense using an effective interest rate method. All highly liquid investments with a maturity date of 90 days or less at the date of purchase are considered to be cash equivalents and the related investment income is recognized in net loss. The appropriate classification of investments in securities is determined by the Company at the time of purchase.

Taxation

As a U.S. tax resident trading entity, we are subject to U.S. corporate taxation. Our U.K. resident trading subsidiaries are individually subject to U.K. corporate taxation. Due to the nature of our business, we have generated losses since inception. We have recorded a full valuation allowance against the deferred tax assets with respect to these tax losses in excess of our deferred tax liabilities in each jurisdiction because we do not consider it more likely than not that there will be suitable taxable profits in the foreseeable future based on the evidence available against which to offset these losses.

Results of Operations

Comparison of the Year Ended December 31, 2023 to the Year Ended December 31, 2022

(in millions) Year Ended

Revenue $ — $ 0.7 $ (0.7)

Operating expenses:

In-process research and development 520.9 — 520.9

Impairment of intangible assets — 8.5 (8.5)

Other expense, net (5.3) (6.7) 1.4

Revenue

Revenue for the year ended December 31, 2022 relates to revenue from our license and commercialization agreement with Eurofarma Laboratórios S.A. for ridinilazole, the Company’s product candidate for treating patients suffering from Clostridioides difficile infection, also known as C. difficile infection. This revenue was recognized ratably over the determined performance period that the research and development services were provided. The decrease for the year ended December 31, 2023 compared to the same period in the prior year is attributed to the total milestones received of $4.8 million being fully recognized ratably over the determined performance period, which ended during 2022. We are currently not anticipating receipt of additional milestone payments under this agreement given Company’s determination that it would seek partners or a divestiture of ridinilazole as the path forward for the clinical development of the asset.

Operating Expenses

Research and Development Expenses

The table below summarizes our research and development expenses by category for the year ended December 31, 2023 and 2022, respectively.

(in millions) Year Ended

Compensation related costs, excluding stock-based compensation 21.3 16.3 5.0

Stock-based compensation 4.4 4.3 0.1

Other research and development costs 4.2 2.8 1.4

The entry into the License Agreement with Akeso, Inc., effective in January 2023, represents a significant change in our strategy from anti-infectives to the therapeutic area of oncology. We have invested our resources in the clinical development of ivonescimab during the year ended December 31, 2023.

Oncology expenses represent our investment in the clinical development of ivonescimab, known as SMT112 in the United States, Canada, Europe, and Japan. On May 3, 2023 we announced plans to initiate Phase III clinical studies for ivonescimab in non-small cell lung cancer (“NSCLC”) and on May 9, 2023, we announced that the first United States-based patient had been enrolled in the Phase III HARMONi study. We have commenced enrollment in our second Phase III HARMONi-3 clinical trial.

We are continuing to focus our efforts on patient enrollment in both the Phase III HARMONi and Phase III HARMONi-3 studies.

With this shift in focus from anti-infectives to oncology, total research and development expenses increased by $7.4 million during the year ended December 31, 2023, compared to the same period in the prior year, primarily due to our investment in oncology expenses of $31.0 million, and an increase in compensation related expenses of $5.0 million to support the clinical development of ivonescimab as we hire experts in the oncology field, partially offset by a decrease of $30.1 million related to discontinuing the development activities related to ridinilazole and SMT-738. We expect oncology-related research and development costs to continue to increase as we progress with the development of ivonescimab. The Company recorded a net benefit related to its anti-infectives programs during the year ended December 31, 2023 due to completing financial close-out activities with the lead contract research organization for our ridinilazole clinical trials, thus resulting in a true-up of the estimated anti-infectives research and development expenses during the second quarter of 2023.

In-process research and development

The table below summarizes our in-process research and development expenses by category for the year ended December 31, 2023 and 2022, respectively.

Year EndedDecember 31,

Upfront milestone payments $ 520.8 $ —

Direct transaction costs 0.1 —

Our investment in ivonescimab totaled $520.9 million for the year ended December 31, 2023 and primarily relates to our upfront milestone payments pursuant to the License Agreement with Akeso. The License Agreement was executed in January 2023, and both Akeso and Summit entered into the Common Stock Issuance Agreement (“Issuance Agreement”). Pursuant to the License Agreement and Issuance Agreement, Akeso elected to receive 10 million shares of our common stock in lieu of $25.1 million cash and was paid $274.9 million in cash as the initial upfront payment. The remaining $200.0 million upfront payment was paid on March 6, 2023. In-process research and development expense comprised of the $474.9 million paid in cash, the fair value of the 10 million shares of common stock on the date of closing the transaction of $45.9 million, and $0.1 million of direct transactions costs incurred.

General and Administrative Expenses

The table below summarizes our general and administrative expenses by category for the year ended December 31, 2023 and 2022, respectively.

(in millions) Year Ended

Stock-based compensation 9.7 7.6 2.1

Legal fees and professional services(1) 6.9 5.5 1.4

Other general and administrative expenses 3.6 3.9 (0.3)

General and administrative expenses increased by $3.6 million for the year ended December 31, 2023, compared to the same period in the prior year, primarily due to an increase of $2.1 million in stock-based compensation as the Company is focused on building its executive management team to continue supporting the growth of the Company, and an increase of $1.4 million in legal and professional services related to corporate projects and transactions. We expect general and administrative expenses to continue to increase in the coming quarters as we scale our infrastructure and management to support development of ivonescimab.

(1) Note management has updated this category to include general and administrative consulting expenses and has reclassified these expenses in the prior period for consistency. Expenses of $1.8 million for the year ended December 31, 2022, were previously recorded in compensation related costs.

Impairment of Intangible Assets

In December 2017, we expanded our activities in the field of infectious diseases with the acquisition of Discuva Limited, a privately held United Kingdom-based company. Through this acquisition, we obtained a bacterial genetics platform and a suite of software-based technologies (collectively termed our “Discuva Platform”), which facilitates the discovery and development of new mechanism antibiotics. In conjunction with the significant change in the Company’s strategy and shift in focus to the therapeutic area of oncology, the Company determined that it will cease further investment in the Discuva Platform and evaluate further options for the use of the Discuva Platform. Management also concluded that this indicated the carrying amount of the acquired Discuva Platform intangible asset may not be recoverable and performed an assessment to calculate the fair value of the asset using a probability-weighted approach which was compared to the carrying value of the asset. An impairment charge of $8.5 million which represented the carrying value of the Discuva Platform was recognized for the year ended December 31, 2022. This impairment charge is presented as impairment of intangible assets in the consolidated statements of operations and comprehensive loss.

Other Operating Income

The table below summarizes our other operating income by category for the year ended December 31, 2023 and 2022, respectively:

(in millions) Year Ended

Funding income from BARDA $ — $ 8.1 $ (8.1)

Research and development tax credits 1.0 4.5 (3.5)

Grant income from CARB-X — 1.8 (1.8)

Funding income from BARDA decreased by $8.1 million for the year ended December 31, 2023, compared to the same periods in the prior year, due to management’s decision to terminate all prior development and marketing activities related to ridinilazole.

U.K. research and development tax credits decreased by $3.5 million for the year ended December 31, 2023, compared to the same period in the prior year, due to a decrease in clinical and manufacturing activity spend associated with the ridinilazole Phase III clinical program, which resulted in a decrease in tax credits claimed in the U.K., coupled with a decrease in eligible expenses claimed due to recent changes in U.K. tax legislation.

Grant income received from CARB-X decreased by $1.8 million for the year ended December 31, 2023, compared to the same period in the prior year due to the CARB-X arrangement for our preclinical candidate SMT-738 concluding in 2022. We do not expect further income under this arrangement.

Other (Expense) Income, Net

The table below summarizes our other income (expense), net by category for the year ended December 31, 2023 and 2022, respectively.

(in millions) Year Ended

Foreign currency gains (losses) $ 0.6 $ (4.1) $ 4.7

Reclassification of cumulative currency translation gain 0.4 — 0.4

Other (expense) income, net primarily decreased by $1.4 million for the year ended December 31, 2023, compared to the same period in the prior year, primarily due to favorable changes in foreign currency gains of $4.7 million, an increase of $9.0 million in interest income related to investments in money market funds and U.S. government securities, and an increase of $0.4 million related to the reclassification of cumulative foreign currency translation gains from accumulated other comprehensive loss due to the dissolution of certain dormant entities, partially offset by an increase of $12.1 million in interest expense on promissory notes to related parties, where amounts recognized in 2023 related to the $520 million promissory notes issued to our Chief Executive Officers.

Liquidity and Capital Resources

Sources of Liquidity

To date, we have financed our operations primarily through issuances of our common stock, issuance of debt, receipt of payments to us under license, collaboration, and commercialization arrangements, for example, our license and commercialization agreement with Eurofarma Laboratórios SA, or Eurofarma, development funding and other assistance from government entities, philanthropic, non-government and not-for-profit organizations for our product candidates. In particular, we have received funding from BARDA, CARB-X, Innovate UK, Wellcome Trust and a number of not-for-profit organizations.

We have devoted substantially all of our efforts to research and development, including clinical trials. We have not completed the development of any drugs. We expect to continue to incur significant expenses and increasing operating losses for at least the next few years. The net losses we incur may fluctuate significantly from quarter to quarter and year to year, due to the nature and timing of our research and development activities. We expect that our research and development and general and administrative expenses will continue to be significant in connection with our ongoing research and development efforts. In addition, if we obtain marketing approval for any of our product candidates in the United States or other jurisdictions where we retain commercial rights, and if we choose to retain those rights, we would expect to incur significant sales, marketing, distribution and outsourced manufacturing expenses, as well as ongoing research and development expenses. In addition, our expenses will increase if and as we:

•Invest in clinical development of ivonescimab in our Licensed Territory;

•conduct research and continue development of additional product candidates;

•maintain and augment our intellectual property portfolio and opportunistically acquire complimentary intellectual property;

•seek further regulatory advancement for ivonescimab;

•invest in our manufacturing capabilities for ivonescimab and any other products for which we may obtain regulatory approval;

•seek marketing approvals for any product candidates that successfully complete clinical development;

•ultimately establish a sales, marketing and distribution infrastructure in jurisdictions where we have retained commercialization rights and scale up external manufacturing capabilities to commercialize any product candidates for which we receive marketing approval;

•perform our obligations under our collaboration agreements;

•pursue business development opportunities, including investing in other businesses, products and technologies;

•experience any delays or encounter any issues with any of the above, including but not limited to failed studies, complex results, safety issues or other regulatory challenges;

•hire additional clinical, regulatory, scientific and administrative personnel;

•expand our physical presence;

•add operational, financial and management information systems and personnel, including personnel to support our product development and planned future commercialization efforts; and

•borrow capital to fund our resources and have to pay interest expenses on such borrowings.

During the year ended December 31, 2023, we incurred a net loss of $614.9 million, and cash flows used in operating activities was $76.8 million. As of December 31, 2023 we had an accumulated deficit of $993.3 million, cash and cash equivalents and short-term investments in U.S. treasury securities of $186.2 million. We expect to continue to generate operating losses for the foreseeable future.

We have evaluated whether our cash, cash equivalents, short-term investments and U.K. research and development tax credits provide sufficient cash to fund our operating cash needs for the next twelve months from the date of issuance of these annual financials. We are investing in the clinical development of ivonescimab, including our ongoing clinical trials. In addition, we have a $100 million promissory note payable to a related party (refer to Note 18 in the consolidated financials included in this Annual Report further details) that matures on April 1, 2025. Based upon our cash and cash equivalents and short-term investments as of December 31, 2023, we expect to be able to operate into the first quarter of 2025. In order to further fund our operating cash needs and repay this promissory note, we intend to raise additional capital. As of the date of the issuance of these financial statements the additional capital has not been secured. As a result, these conditions raise substantial doubt about our ability to continue as a going concern.

In addition to the payments already made to Akeso, under the License Agreement there are additional potential milestone payments of $4.5 billion, as Akeso will be eligible to receive regulatory milestones of up to $1.05 billion and commercial milestones of up to $3.45 billion. In addition, Akeso will be eligible to receive low double-digit royalties on net sales. Until we can generate substantial revenue and achieve profitability, we will need to raise additional capital to fund ongoing operations and capital needs, including the payment of the milestone payments referenced above.

We have based the foregoing estimate on assumptions that may prove to be wrong, and we could use our capital resources sooner than we currently expect. This estimate assumes, among other things, that we do not obtain any additional funding through grants and clinical trial support or through new collaboration arrangements. Our future capital requirements will depend on many factors, including:

•the costs, timing and outcome of clinical trials required for clinical development of ivonescimab;

•the costs, timing and outcome of activities related to development, validation, manufacturing and establishment of supply chain for ivonescimab;

•the number and development requirements of other future product candidates that we pursue;

•the costs, timing and outcome of regulatory review of ivonescimab and/or our other product candidates we develop;

•the costs and timing of commercialization activities, including product sales, marketing, distribution and manufacturing, for any of our product candidates that receive marketing approval;

•the extent to which we become liable formilestone payments under our Licensing Agreement for ivonescimab;

•subject to receipt of marketing approval, revenue received from commercial sales of any product candidates;

•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 ability to establish and maintain collaborations, licensing or other arrangements and the financial terms of such arrangements;

•the extent to which we acquire or invest in other businesses, products and technologies;

•the rate of the expansion of our physical presence; and

•the extent to which we change our physical presence.

Until such time, if ever, as we can generate substantial product revenues, we expect to finance our cash needs 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.

We will need to seek additional funding in the future to fund operations. Additional capital, when needed, may not be available to us on acceptable terms, or at all. To the extent that we raise additional capital through the sale of equity or convertible debt securities, the ownership interest of our existing stockholders may be diluted, and the terms of these securities may include liquidation or other preferences that adversely affect the rights of our existing stockholders. Additional debt financing, if available, may involve agreements that include covenants limiting or restricting our ability to take specific actions, such as

incurring additional debt, making capital expenditures or declaring dividends or other distributions. If we raise additional funds through collaborations, strategic alliances or marketing, distribution, or licensing arrangements with third parties, we may have to relinquish valuable rights to our technologies, future revenue streams, research programs or product candidates or to grant licenses on terms that may not be favorable to us.

If we are unable to raise additional funds through equity or debt financings or other arrangements when needed, we may be required to delay, limit, reduce or terminate our product development or future commercialization efforts or grant rights to develop and market product candidates that we would otherwise prefer to develop and market ourselves, which could materially adversely affect our business prospects or our ability to continue operations.

Cash Flows

The following table summarizes the results of our cash flows for the years ended December 31, 2023 and 2022.

(in millions) Year Ended December 31, 2023 Year Ended December 31, 2022

Net cash used in operating activities $ (76.8) $ (41.6)

Net cash used in investing activities $ (587.8) $ (0.6)

Net cash provided by financing activities $ 86.5 $ 620.2

Operating Activities

Net cash used in operating activities for the year ended December 31, 2023 was $76.8 million and resulted from a net loss of $614.9 million, which included an adjustment of $475.0 million in cash payments related to investing activities for the purchase of in-process research and development from Akeso under the terms of the License Agreement and the associated direct transaction costs and non-cash charges of $65.5 million and a net increase in working capital of $2.4 million. Non-cash charges primarily include a $45.9 million expense for the issuance of shares in lieu of cash for the Akeso upfront payment, $14.1 million of stock-based compensation, $6.3 million related to non-cash interest expense, $1.9 million related to amortization of right-of-use assets, and a $0.5 million impairment charge, partially offset by $1.9 million related to amortization of discount on short-term investments and $0.8 million in a net unrealized foreign exchange gain. The net increase in working capital is primarily due to a $3.7 million increase in other long-term assets, a $2.4 million decrease in accrued liabilities, and a $2.2 million decrease in lease liabilities , partially offset by a $4.2 million decrease in the research and development tax credit receivable and a $2.3 million increase in accounts payable.

Net cash used in operating activities for the year ended December 31, 2022 was $41.6 million and resulted from a net loss of $78.8 million, which included non-cash charges of $28.6 million and a $8.6 million net decrease in working capital. Non-cash charges primarily include $11.9 million of stock-based compensation, a $8.5 million impairment charge, $4.3 million related to non-cash interest expense, a $2.6 million unrealized foreign currency exchange loss, and $1.3 million in amortization of right-of-use assets, partially offset by a $1.3 million gain on remeasurement of an assumed contingent liability. The net decrease in working capital primarily includes an $8.4 million decrease in research and development tax credit receivable, a $5.1 million decrease in prepaid expenses, a $4.8 million increase in accrued liabilities, and a $1.6 million increase in accrued compensation, partially offset by a $7.3 million decrease in deferred revenue and income, a $4.1 million decrease in accounts payable, and a $1.1 million decrease in lease liabilities.

Investing Activities

Net cash used in investing activities for the years ended December 31, 2023 was $587.8 million and was primarily due to $475.0 million of cash payments made to Akeso pursuant to the License Agreement and $112.9 million of net purchases of short-term investments. Net cash used in investing activities for the year ended December 31, 2022 was for the purchase of property and equipment.

Financing Activities

Net cash provided by financing activities for the year ended December 31, 2023 was $86.5 million and was primarily due to net proceeds received of $104.1 million (net of paid issuance costs) related to the issuance of common stock from the 2023 Rights Offering and net of the extinguishment of $395.3 million of principal and accrued interest due and payable by us under

the $400 million Duggan Promissory Note in satisfaction of the subscription price for the shares subscribed by Mr. Duggan in the 2023 Rights Offering, $5.0 million received for the issuance of common stock via a private placement to a related party, and $1.2 million received for the exercise of stock option warrants, partially offset by the repayment of $24.7 million related to promissory notes from related parties.

Net cash provided by financing activities for the year ended December 31, 2022 was $620.2 million and primarily resulted from net proceeds of $99.9 million from the rights offering in August 2022, proceeds from promissory notes from related parties of $545.0 million, partially offset by the repayment of a promissory note from a related party of $25.0 million and $0.4 million of net proceeds from the exercise of stock options.

Contractual Obligations and Commitments

Fixed asset purchase commitments

At December 31, 2023 and 2022, we had no capital commitments.

Lease commitments

The following table summarizes our lease contractual obligations as of December 31, 2023.

Payment due by period

Operating lease obligations $6.6 $2.8 $3.8 $ — $ —

The table above does not include the lease agreement signed by the Company on January 8, 2024 for executive office space for its new headquarters in Miami, Florida. The office space is approximately 9,000 square feet. The term of the lease is 64 months. Total payments for this office space is approximately $5.1 million over the term of the lease. The table above excludes payments related to the lease signed in January 2024.

Debt commitments

On December 6, 2022, we entered into a Note Purchase Agreement (the “Note Purchase Agreement”), with Mr. Robert Duggan and Dr. Maky Zanganeh, pursuant to which the Company agreed to sell to each of Mr. Duggan and Dr. Zanganeh unsecured promissory notes in the aggregate amount of $520 million. Pursuant to the Note Purchase Agreement, the Company issued to Mr. Duggan and Dr. Zanganeh unsecured promissory notes in the amount of $400 million (the “Duggan February Note”) and $20 million (the “Zanganeh Note”), respectively, which matured and became due on February 15, 2023 and an unsecured promissory note to Mr. Duggan in the amount of $100 million (the “Duggan September Note” and together with the Duggan February Note and the Zanganeh Note, the “December 2022 Notes”), which was originally due on September 15, 2023. The maturity dates of the December 2022 Notes could have been extended one or more times at the Company’s election, but in no event to a date later than September 6, 2024. In addition, if the Company consummates a public offering, then upon the later to occur of (i) five business days after the Company receives the net cash proceeds therefrom or (ii) May 15, 2023, the Duggan February Note and the Zanganeh Note shall be prepaid by an amount equal to the lesser of (a) 100% of the amount of the net proceeds of such offering and (b) the outstanding principal amount on such Notes. On January 19, 2023, the Company provided notice to extend the term of the Duggan February Note and Duggan September Note to a maturity date of September 6, 2024. Furthermore, on January 19, 2023, the Company and Mr. Duggan rectified the Duggan February Note and Duggan September Note in order to correctly reflect the parties’ intent that the Company may only prepay (i) the Duggan February Note following the completion of a public rights offering to be conducted by Summit in the approximate amount of $500 million (the “Rights Offering”), or a similar capital raise, in an amount equal to the lesser of (x) the net proceeds of the Rights Offering or such capital raise or (y) the full amount outstanding of the Duggan February Note, and (ii) the Duggan September Note following the completion of a capital raising transaction subsequent to the Rights Offering in an amount equal to the lesser of (A) the net proceeds of such capital raise or (B) the full amount outstanding of the Duggan September Note. Following the issuance of the two new Promissory Notes (the “Duggan Promissory Notes”), the Duggan February Note and Duggan September Note were marked as “cancelled” on their face and replaced in their entirety by the Duggan Promissory Notes (together with the Zanganeh Note, the “Notes”). The Notes accrue interest at an initial rate of 7.5%. All interest on the Notes shall be paid on the date of signing for the period through February 15, 2023. Such prepaid interest shall be paid in a number of shares of the Company’s common stock, par value $0.01 (“Common Stock”) equal to the dollar amount of such prepaid interest, divided by $0.7913 (the

consolidated closing bid price immediately preceding the time the Company entered into the Note Purchase Agreement, plus $.01), which was 9,720,291 shares. For all applicable periods following February 15, 2023, interest shall accrue on the outstanding principal balance of the Notes at the US prime interest rate, as reported in the Wall Street Journal, plus 50 basis points, as adjusted monthly, for three months immediately following February 15, 2023, and thereafter at the US prime rate plus 300 basis points, as adjusted monthly. On February 15, 2023, the $20 million Zanganeh Note matured and we repaid the outstanding principal balance. In connection with the closing of the Rights Offering, the $400 million Duggan Promissory Note matured and became due, and we repaid all principal and accrued interest thereunder using a portion of the proceeds from the Rights Offering.

On February 17, 2024 the Duggan February Note was amended to extend the maturity date from September 6, 2024 to April 1, 2025. For all applicable periods commencing February 17, 2024, interest shall accrue on the outstanding principal balance at the greater of 12% or the US prime interest rate, as reported in the Wall Street Journal plus 350 basis points, as adjusted monthly, compounded quarterly. Interest shall be paid upon maturity of the loan.

The estimated future principal payments are $0 and $100,000,000 for 2024 and 2025, respectively, as the note matures on April 1, 2025.

Other commitments

We enter into contracts in the normal course of business with various third parties for clinical trials, preclinical research studies and testing, manufacturing and other services and products for operating purposes. Most contracts provide for termination upon notice, and therefore are cancellable contracts. As of December 31, 2023, total contractual commitments, excluding leases commitments and debt commitments, are estimated to be approximately $37.7 million and the majority of these commitments are due within one year.

Subsequent to December 31, 2023 through February 9, 2024, the Company entered into additional contractual commitments of approximately $23.0 million with various third parties related to our clinical trials.

We have certain commitments under our agreements with Akeso, Wellcome Trust, the University College London and certain employees, former employees and former directors of Discuva, pursuant to which we will be required to pay royalties or make milestone payments. The License Agreement with Akeso also contains certain manufacturing and purchase commitments. As of December 31, 2023, we are unable to estimate the amount, timing or likelihood of achieving the milestones, making future product sales or assessing estimated forecasts for manufacturing and supplied materials which these contingent payment obligations relate to.

Indemnifications

Our certificate of incorporation provides that it will indemnify the directors and officers to the fullest extent permitted by Delaware law. In addition, we have entered into indemnification agreements with all of the directors and executive officers. These indemnification agreements may require us, among other things, to indemnify each such director or executive officer for some expenses, including attorneys’ fees, judgments, fines, and settlement amounts incurred by him or her in any action or proceeding arising out of his or her service as one of our directors or executive officers. We believe the fair value for these indemnification obligations is minimal. Accordingly, we have not recognized any liabilities relating to these obligations as of December 31, 2023.

Legal Proceedings

We are not currently subject to any material legal proceedings.

Critical Accounting Policies and Significant Judgments and Estimates

Our management’s discussion and analysis of our financial condition and results of operations are based on our consolidated financial statements, which have been prepared in accordance with United States generally accepted accounting principles. The preparation of these financial statements requires us to make estimates and judgments that affect the reported amounts of assets, liabilities, and expenses and the disclosure of contingent assets and liabilities in our financial statements. On an ongoing basis, we evaluate our estimates and judgments, including those related to accrued research and development expenses, stock-based compensation and income taxes. We base our estimates on historical experience, known trends and events, and various other factors that we believe 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.

We believe the following critical accounting policies affect the most significant judgments, assumptions and estimates we use in preparing the consolidated financial statements:

Acquired In-Process Research and Development

The Company may enter into agreements with collaboration partners for the development and commercialization of its products. These arrangements may include payments contingent on the occurrence of certain events such as development, regulatory or sales-based milestones. The Company considers the unique nature, terms and facts and circumstances of each transaction. The Company considers whether or not the assets acquired have a future alternative use.

The fair value associated with acquired in-process research and development which does not have an alternative future use is expensed and is recorded as research and development expense. Any development or commercial milestone payments are recognized when the achievement of the associated milestone becomes probable and will either be expensed or capitalized depending upon whether or not regulatory approval has been obtained.

Research and Development Costs

Research and development costs are expensed as incurred. Research and development expenses consist of costs incurred to discover, research and develop product candidates, including personnel expenses, stock-based compensation expense, allocated facility-related and depreciation expenses, third-party license fees and external costs of outside vendors engaged to conduct preclinical and clinical development activities and clinical trials as well as to manufacture clinical trial materials. Non - refundable prepayments for goods or services that will be used or rendered for future research and development activities are recorded as prepaid expenses. Such amounts are recognized as an expense as the goods are delivered or the related services are performed, or until it is no longer expected that the goods will be delivered, or the services rendered. The significant estimates in our accrued research and development expenses include the costs incurred for services performed by our vendors in connection with research and development activities for which we have not yet been invoiced. Milestone and other payments made to third-parties with respect to in-process research and development, in accordance with the Company’s license, acquisition and other similar agreements are expensed when determined to be probable and estimable.

The Company has entered into various research and development contracts with other companies. These agreements are generally cancellable, and related payments are recorded as research and development expenses as incurred. The Company records accruals for estimated ongoing research and development costs or prepaid expenses where the payments made exceeds the estimated costs. When evaluating the adequacy of these balances, the Company analyzes progress of the studies, including the estimated costs to complete each study or activity, 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. Actual results could differ from the Company’s estimates. In all cases, the full cost of each study or activity is expensed by the time the final report or where applicable, product, has been received. The Company’s historical estimates have not been materially different from the actual costs.

Stock-Based Compensation

The Company measures and recognizes compensation expense for all stock option and restricted stock unit awards based on the estimated fair value of the award on the grant date. The Company uses the Black-Scholes option pricing model to estimate the fair value of stock option awards. Additionally, the Company uses a Monte Carlo simulation model to calculate the estimated fair value on the date of grant related to awards with market-based service conditions. The fair value is recognized as expense, over the requisite service period, which is generally the vesting period of the respective award, on a straight-line basis for each separately vesting portion of the award when the only condition to vesting is continued service.If vesting is subject to a market or performance condition, recognition is based on the derived service period of the award. Expense for awards with performance conditions is estimated and adjusted on a quarterly basis based upon the assessment of the probability that the performance condition will be met. Use of the Black-Scholes option-pricing model requires management to apply judgment under highly subjective assumptions.These assumptions include:

•Expected term—The expected term of stock options represents the weighted-average period the stock options are expected to be outstanding. The Company uses the simplified method for estimating the expected term as provided by the Securities and Exchange Commission. The simplified method calculates the expected term as the average of the time-to-vesting and the contractual life of the options.

•Expected volatility—The expected volatility is calculated based on historical volatility of the Company’s share price.

•Risk-free interest rate—The risk-free rate assumption is based on the U.S. Treasury instruments, the terms of which were consistent with the expected term of the Company’s stock options.

•Expected dividend—The expected dividend assumption is based on the Company’s history and expectation of dividend payouts. The Company has not paid and does not intend to pay dividends.

The Company estimates expected forfeitures at the time of grant instead of accounting for forfeitures as they occur. Stock option and restricted stock unit awards have been granted at fair value to non-employees, in connection with research and consulting services provided to the Company, to non-employees in connection with corporate activities, and to employees, in connection with Stock Purchase and Restriction Agreements. Equity awards generally vest over terms of 3 or 4 years.

The Company classifies stock-based compensation expense in the consolidated statements of operations in the same manner in which the award recipient’s payroll costs are classified.

Income Taxes

The provision for income taxes is determined using the asset and liability approach. Tax laws may require items to be included in tax filings at different times than the items are reflected in the financial statements. A current asset or liability is recognized for the estimated taxes receivable or payable for the current year. Deferred taxes represent the future tax consequences expected to occur when the reported amounts of assets and liabilities are recovered or paid. Deferred taxes are initially recognized at enacted tax rates in force at the time of initial recognition and are subsequently adjusted for any enacted changes in tax rates and tax laws. Subsequent changes to deferred taxes originally recognized in equity are recognized in income. Valuation allowances are recorded to reduce deferred tax assets when it is more likely than not that a tax benefit will not be realized. The Company has recorded a full valuation allowance against the deferred tax assets in excess of its deferred tax liabilities, as the deferred tax liability represents future reversals of existing taxable temporary differences. The Company records interest and penalties related to income tax matters as part of income tax expense.

The Company accounts for uncertainty in income taxes by applying a two-step process to determine the amount of tax benefit to be recognized. First, the tax position must be evaluated to determine the likelihood that it will be sustained upon external examination by the taxing authorities. If the tax position is deemed more-likely-than-not to be sustained, the tax position is then assessed as the amount of benefit to recognize in the consolidated financial statements. The amount of benefits that may be used is the largest amount that has a greater than 50% likelihood of being realized upon ultimate settlement. The provision for income taxes includes the effects of any resulting tax reserves, or unrecognized tax benefits, that are considered appropriate, as well as the related net interest and penalties. At December 31, 2023 and 2022, the Company had unrecognized tax positions of $1.1 million and nil, respectively. Due to the Company’s full valuation allowance, the unrecognized tax benefits would not materially impact the Company’s effective tax rate when recognized. The Company does not anticipate the total amount of unrecognized tax benefits to significantly increase or decrease in the next 12 months. The Company’s policy is to recognize interest and penalties related to uncertain tax positions as part of its income tax provision. For the years ended December 31, 2023 and 2022, the Company had no interest or penalties related to unrecognized tax benefits.

Recent Accounting Pronouncements

For a discussion of recent accounting pronouncements, please see Note 5 to our consolidated financial statements contained in this Annual Report on Form 10-K.

Item 7A. Quantitative and Qualitative Disclosures About Market Risk

Our primary exposures to market risk are liquidity risk and foreign currency risk.

Liquidity Risk

We have funded our operations since inception primarily through the issuance of equity and debt securities. We have also received funding from our license, collaboration, and commercialization arrangements, for example, our license and commercialization agreement with Eurofarma, as well as philanthropic, non-government and not-for-profit organizations and grant funding from government entities, including BARDA, CARB-X, Innovate UK, Wellcome Trust and a number of not-for-profit organizations. Until such time as we can generate significant revenue from product sales, if ever, we expect to finance our operations through a combination of public or private equity or debt financings or other sources. Adequate additional financing may not be available to us on acceptable terms, or at all. Our inability to raise capital as and when needed would have a negative impact on our financial condition and our ability to pursue our business strategy.

Foreign Currency Exchange Rate Risk

Foreign currency exchange rate risk refers to the risk that the value of a financial commitment or recognized asset or liability will fluctuate due to changes in foreign currency rates. Our net loss and financial position, as expressed in U.S. dollars, are exposed to movements in foreign exchange rates against the pound sterling and the euro. The main trading currencies are the pound sterling, the U.S. dollar, and the euro. We are exposed to foreign currency exchange rate risk as a result of entering into operating transactions denominated in currencies other than the functional currency of our subsidiaries, particularly in relation to our monetary assets and liabilities relating to intercompany transactions, supplier liabilities and the translation of foreign cash balances. Operating transaction foreign currency gains and losses are included in the determination of net loss in our statements of operations. We monitor our exposure to foreign currency exchange rate risk. Exposures are generally managed through natural hedging via the currency denomination of cash balances and any impact currently is not material to us.

Interest Rate Risk

We hold our cash, cash equivalents and short-term investments for working capital purposes. Some of the securities we invest in are subject to market risk. This means that a change in prevailing interest rates may cause the principal amount of such investments to fluctuate. To minimize this risk, we maintain our portfolio of cash, cash equivalents and short-term investments which are invested in a variety of short term securities, including money market funds and investments in U.S. treasury securities. Due to the short-term nature of these instruments, we believe that we do not have any material exposure to changes in the fair value of our investment portfolio as a result of changes in interest rates. Declines in interest rates, however, would reduce future interest income. The effect of a hypothetical 10% increase or decrease in overall interest rates would not have had a material impact on our operating results or the total fair value of our portfolio.

We are exposed to market risks related to fluctuations in interest rates related to our promissory notes payable to related parties. As of December 31, 2022, the principal balance payable was $520 million, the outstanding principal balance is subject to a variable interest rate from February 15, 2023. As of December 31, 2023, the principal balance outstanding was $100.0 million. For all applicable periods following February 15, 2023, interest accrued on the outstanding principal balance at the United States prime interest rate, as reported in the Wall Street Journal, plus 50 basis points, as adjusted monthly, for three months immediately following February 15, 2023, and thereafter at the United States prime rate plus 300 basis points, as adjusted monthly. On February 17, 2024 the Duggan February Note was amended to extend the maturity date from September 6, 2024 to April 1, 2025. For all applicable periods commencing February 17, 2024, interest shall accrue on the outstanding principal balance at the greater of 12% or the US prime interest rate, as reported in the Wall Street Journal plus 350 basis points, as adjusted monthly, compounded quarterly. Interest shall be paid upon maturity of the loan.

Credit Risk

We consider all of our material counterparties to be creditworthy. We consider the credit risk for each of our counterparties to be low and do not have a significant concentration of credit risk at any of our counterparties. We have $1.8 million of research and development tax credits outstanding at December 31, 2023. Given that these receivables relate to U.K. research and development tax credit cash rebate regimes and given our history of collection, it is highly unlikely that these amounts will not be collected.

Item 8. Financial Statements and Supplementary Data

The financial statements required to be filed pursuant to this Item 8 are included in this Annual Report on Form 10-K. An index of those financial statements is found in Item 15.

Item 9. Changes in and Disagreements with Accountants on Accounting and Financial Disclosure

None.

Item 9A. Controls and Procedures

Evaluation of Disclosure Controls and Procedures

We have carried out an evaluation of the effectiveness of the design and operation of our disclosure controls and procedures (as such term is defined in Rules 13a-15(e) and 15d-15(e) under the Exchange Act) under the supervision and the participation of the company’s management, which is responsible for the management of the internal controls, and which includes our Chief Executive Officers (our Principal Executive Officers) and our Chief Financial Officer (our Principal Financial Officer). The term “disclosure controls and procedures,” as defined in Rules 13a-15(e) and 15d-15(e) under the Securities Exchange Act of 1934, means controls and other procedures of a company that are designed to ensure that information required to be disclosed by a company in the reports that it files or submits under the Securities Exchange Act of 1934 is recorded, processed, summarized and reported within the time periods specified in the Securities and Exchange Commission’s rules and forms. Disclosure controls and procedures include, without limitation, controls and procedures designed to ensure that information required to be disclosed by a company in the reports that it files or submits under the Securities Exchange Act of 1934 is accumulated and communicated to the company’s management, including its principal executive and principal financial officers, as appropriate to allow timely decisions regarding required disclosure. There are inherent limitations to the effectiveness of any system of disclosure controls and procedures, including the possibility of human error and the circumvention or overriding of the controls and procedures. Accordingly, even effective disclosure controls and procedures can only provide reasonable assurance of achieving their control objectives. Based upon our evaluation of our disclosure controls and procedures as of December 31, 2023, our Chief Executive Officer and Executive Chairman and Chief Executive Officer, President and Director (our Principal Executive Officers), and our Chief Financial Officer (our Principal Financial Officer) concluded that, as of such date, our disclosure controls and procedures were effective at a reasonable level of assurance.

Management’s Report on Internal Control Over Financial Reporting

Our management is responsible for establishing and maintaining adequate internal control over financial reporting. Our internal control over financial reporting is a process designed, under the supervision of the Chief Executive Officers (our Principal Executive Officers), and our Chief Financial Officer (our Principal Financial Officer), to provide reasonable assurance regarding the reliability of financial reporting and the preparation of our financial statements for external reporting purposes in accordance with Generally Accepted Accounting Principles.

Because of its inherent limitations, internal control over financial reporting may not prevent or detect all misstatements. Moreover, projections of any evaluation of the effectiveness of internal control to future periods are subject to a risk that controls may become inadequate because of changes in conditions and that the degree of compliance with the policies or procedures may deteriorate.

Our management has assessed the effectiveness of internal control over financial reporting as of December 31, 2023, based on the Internal Control—Integrated Framework issued by the Committee of Sponsoring Organizations of the Treadway Commission (COSO) 2013. Based on this assessment, our management has concluded that our internal control over financial reporting as of December 31, 2023, was effective.

This report does not include an attestation report of our registered public accounting firm as we are a non-accelerated filer and a smaller reporting company.

Changes in Internal Control Over Financial Reporting

There were no changes in our internal control over financial reporting (as defined in Rules 13a‐15(f) and 15d‐15(f) under the Exchange Act) during the quarter ended December 31, 2023 that have materially affected, or are reasonably likely to materially affect, our internal control over financial reporting.

Item 9B. Other Information

Item 9C. Disclosure Regarding Foreign Jurisdictions that Prevent Inspections

Not applicable.

PART IIIs

Item 10. Directors, Executive Officers and Corporate Governance

CORPORATE GOVERNANCE

Overview

Our Board of Directors oversees our Chief Executive Officers, and other senior management in the competent and ethical operation of our business and affairs and assures that the long-term interests of the stockholders are being served. Our Board of Directors has adopted Corporate Governance Guidelines that address items such as the qualifications and responsibilities of our directors and director candidates and corporate governance policies and standards applicable to us in general. We believe that good governance leads to high board effectiveness, promotes the long-term interests of our stockholders, strengthens the accountability of our Board of Directors and management and improves our standing in our industry.

Board Leadership Structure

Our Board of Directors believes that the roles of Chairman and Chief Executive Officer may be filled by the same or different individuals. This allows our Board of Directors to have the flexibility to determine whether the two roles should be combined or separated based upon the needs of the Company and our Board of Directors’ assessment of our leadership from time to time. Our Board of Directors also believes that combining the role of Chairman and Chief Executive Officer facilitates the strategic development of the Company and the flow of information between the Board and management. In our Board’s view, Mr. Duggan is best situated to serve as Chairman because of his familiarity with the Company’s business and industry and his insight into the strategies and policies to be discussed by the Board of Directors. At this time, our Board of Directors believes it is in the best interests of our Company and our stockholders for Robert W. Duggan to serve as our Chief Executive Officer and Chairman of the Board of Directors. The Chairman of the Board of Directors presides over all Board meetings and approves the agenda for meetings of the Board of Directors. He also works with the Board of Directors to drive decisions about particular strategies and policies.

The Appointment of the Lead Independent Director

Our Board of Directors has determined that it is advisable, in light of having the same person, Robert W. Duggan, serve as both Chief Executive Officer and Chairman of the Board of Directors, to appoint a lead independent director (“LID”). The Board of Directors has approved the appointment of Kenneth Clark as LID. The LID shall be responsible for the following duties: (i) to chair any meeting of the independent directors in executive sessions; (ii) to meet with any director who is not adequately performing his or her duties as a member of the Board of Directors; (iii) to facilitate communications between other members of the Board of Directors and the Chairman of the Board and Chief Executive Officer; (iv) to monitor, with the

assistance of the Company’s legal advisors, communications from stockholders and other interested parties; (v) to work with the Chairman of the Board in the preparation of the agenda for each Board of Directors meeting; and (vi) to otherwise consult with the Chairman of the Board and Chief Executive Officer on corporate governance matters and the Board of Directors’ performance.

The Board of Director’s Role in Risk Oversight

Our management has day-to-day responsibility for identifying risks facing us, including implementing suitable mitigating processes and controls, assessing risks in relation to Company strategies and objectives, and appropriately managing risks in a manner that serves the best interests of the Company, our stockholders, and other stakeholders. Our Board of Directors is responsible for ensuring that an appropriate culture of risk management exists within the Company and for setting the right “tone at the top,” overseeing our aggregate risk profile, and assisting management in addressing specific risks.

Generally, various committees of our Board of Directors oversee risks associated with their respective areas of responsibility and expertise. For example, our Audit Committee oversees, reviews and discusses with management and the independent auditor risks associated with our internal controls and procedures for financial reporting and the steps management has taken to monitor and mitigate those exposures; our Audit Committee also oversees the management of other risks, including those associated with credit risk. Our Compensation Committee oversees the management of risks associated with our compensation policies, plans and practices. Our Nominating and Corporate Governance Committee oversees the management of risks associated with director independence and the composition and organization of the Board of Directors. Our Board of Directors provides direct oversight over cybersecurity risks. Management and other employees report to the Board of Directors and/or relevant committee from time to time on risk-related issues.

Diversity of the Board

Although the Nominating and Corporate Governance Committee does not maintain a specific policy with respect to board diversity, the Board of Directors believes that the Board of Directors should be a diverse body. Diversity in experiences, perspectives, and backgrounds is just one of many factors considered by the Nominating and Corporate Governance Committee in considering director nominees. In August 2021, the SEC adopted Nasdaq’s proposal that requires listed companies to provide statistical information about their boards of directors, in the form of a matrix chart. The below Diversity Matrix reports self-identified diversity statistics for the Board in the format required by Nasdaq’s rules.

Board Diversity Matrix (as of February 13, 2024)

Total Number of Directors 8

Female Male Non-Binary Did Not Disclose Gender

Gender Identity

Directors 4 4 — —

Demographic Background

African American or Black — — — —

Alaskan Native or Native American — — — —

Asian 2 1 — —

Hispanic or Latinx — — — —

Native Hawaiian or Pacific Islander — — — —

White 2 3 — —

Two or More Races or Ethnicities — — — —

LGBTQ+ — — — —

Did Not Disclose Demographic Background — — — —

Director Independence

Under applicable Nasdaq rules, a director will only qualify as an “independent director” if, in the opinion of the listed company’s board of directors, that person does not have a relationship that would interfere with the exercise of independent

judgment in carrying out the responsibilities of a director. In order to be considered independent for purposes of Rule 10A-3, a member of an audit committee of a listed company may not, other than in his or her capacity as a member of the audit committee, the board of directors, or any other board committee, accept, directly or indirectly, any consulting, advisory, or other compensatory fee from the listed company or any of its subsidiaries or otherwise be an affiliated person of the listed company or any of its subsidiaries. In order to be considered independent for purposes of Rule 10C-1, the board must consider, for each member of a compensation committee of a listed company, all factors specifically relevant to determining whether a director has a relationship to such company which is material to that director’s ability to be independent from management in connection with the duties of a compensation committee member, including, but not limited to: (1) the source of compensation of the director, including any consulting advisory or other compensatory fee paid by such company to the director; and (2) whether the director is affiliated with the company or any of its subsidiaries or affiliates.

Based upon information requested from and provided by each director concerning his or her background, employment and affiliations, including family relationships, our Board of Directors has determined that each of Mr. Clark, Ms. Mahatme, Mr. Booth and Ms. Cesano, representing four of our eight directors, is “independent” as that term is defined under the rules of The Nasdaq Stock Market and none of these directors has or has had a relationship that would interfere with the exercise of independent judgment in carrying out the responsibilities of a director.

Our Board of Directors also determined that Mr. Clark, Ms. Mahatme, Mr. Booth, and Ms. Cesano, who comprise our Audit Committee, Compensation Committee, and Nominating and Corporate Governance Committee, satisfy the independence standards for those committees established by applicable SEC rules, including Rule 10A-3 of the Exchange Act, and the rules of The Nasdaq Stock Market. In making this determination, our Board of Directors considered the relationships that each non-employee director has or has had with our Company and all other facts and circumstances that our Board of Directors deemed relevant in determining their independence, including the beneficial ownership of our capital stock by each non-employee director.

Under The Nasdaq Stock Market listing requirements, a company of which more than 50% of the voting power is held by an individual, group, or another company is a “controlled company.” Because Mr. Duggan owns more than a majority of the voting power of our outstanding shares of common stock, we are a “controlled company” under the corporate governance rules for Nasdaq-listed companies. A “controlled company” may elect not to comply with certain Nasdaq corporate governance requirements, including the requirements that:

•a majority of the board of directors consist of independent directors;

•the compensation committee be composed entirely of directors meeting Nasdaq independence standards applicable to compensation committee members with a written charter addressing the committee’s purpose and responsibilities;

•the compensation committee be responsible for the hiring and overseeing of persons acting as compensation consultants and be required to consider certain independence factors when engaging such persons; and

•director nominees either be selected, or recommended for board of directors’ selection, either by “independent directors” as defined under the rules of Nasdaq constituting a majority of the board of director’s “independent directors” in a vote in which only “independent directors” participate, or by a nominations committee comprised solely of “independent directors.”

We have elected to take advantage of these exemptions. As a result, our stockholders may not have the same protections afforded to stockholders of companies that are subject to all of the Nasdaq corporate governance rules.

Director Nominations

Candidates for nomination to our Board of Directors are selected by the Nominating and Corporate Governance Committee in accordance with the committee’s charter, and our Certificate of Incorporation and Bylaws. The Nominating and Corporate Governance Committee evaluates all candidates in the same manner and using the same criteria, regardless of the source of the recommendation.

The Nominating and Corporate Governance Committee may retain recruiting professionals to assist in identifying and evaluating candidates for director nominees. Our Board of Directors has adopted Corporate Governance Guidelines and the Nominating and Corporate Governance Committee has adopted Policies and Procedures for Director Candidates which sets out, among other things, that the Nominating and Corporate Governance Committee considers factors such as character, integrity, judgment, diversity of experience (including age, gender, international background, race and professional experience), independence, area of expertise, length of service, potential conflicts of interest, other commitments and the like. The

Nominating and Corporate Governance Committee considers the following minimum qualifications to be satisfied by any nominee to the Board of Directors: a reputation for integrity, honesty and adherence to high ethical standards; a demonstrated business acumen, experience and ability to exercise sound judgments in matters that relate to the current and long-term objectives of the Company; a commitment to understanding the Company and its industry; a commitment to regularly attend and participate in meetings of the Board and its committees; an interest and ability to understand the sometimes conflicting interests of the various constituencies of the Company, including stockholders, employees, customers, governmental units, creditors and the general public, and to act in the interests of all stockholders. Based on the Nominating and Corporate Governance Committee’s recommendation, the Board of Directors selects director nominees and recommends them for election by our stockholders, and also fills any vacancies that may arise between annual meetings of stockholders.

The Nominating and Corporate Governance Committee will consider director candidates who are proposed by our stockholders in accordance with our Bylaws, our Nominating and Corporate Governance Committee’s Policies and Procedures for Director Candidates and other procedures established from time to time by the Nominating and Corporate Governance Committee. If you would like the Nominating and Corporate Governance Committee to consider a prospective director candidate, please follow the procedures in our Bylaws and submit the candidate’s name and qualifications to: Corporate Secretary, Summit Therapeutics Inc., 601 Brickell Key Drive, Suite 1000, Miami, FL 33131.

Code of Business Conduct and Ethics

We have also adopted a written code of business conduct and ethics that applies to our directors, officers and employees, including our principal executive officers, principal financial officer, principal accounting officer or controller, or persons performing similar functions. A copy of the code is filed herewith as Exhibit 14.1 and posted on the “Investor Center/Corporate Governance” section of our website, which is located at https://www.smmttx.com/. If we make any substantive amendments to, or grant any waivers from, the code of business conduct and ethics for any officer or director, we will disclose the nature of such amendment or waiver on our website or in a current report on Form 8-K to be filed with the SEC.

Policy on Short Sales, Derivative Transactions and Hedging Transactions

The Company’s Insider Trading Policy prohibits any director or employee from engaging in any of the following types of transactions with respect to the Company’s securities: (i) short sales, including short sales “against the box”, (ii) purchases or sales of puts, calls, or other derivative securities or (iii) purchases of financial instruments (including prepaid variable forward contracts, equity swaps, collars and exchange funds) or other similar transactions that directly hedge or offset, or are designed to directly hedge or offset, any decrease in the market value of Company securities.

Communication with the Board of Directors

Any stockholder communication with our Board of Directors or individual directors should be directed to Summit Therapeutics Inc., c/o Corporate Secretary, 601 Brickell Key Drive, Suite 1000, Miami, FL 33131. The Corporate Secretary will forward these communications, as appropriate, directly to the director(s). The independent directors of the Board of Directors review and approve the stockholder communication process periodically in an effort to enable an effective method by which stockholders can communicate with the Board of Directors.

BOARD OF DIRECTORS AND COMMITTEES OF THE BOARD

Board and Committee Meetings

Our Board of Directors and its committees meet throughout the year on a set schedule, hold special meetings as needed, and act by written consent from time to time. During fiscal year 2023, our Board of Directors held 3 meetings, and each director attended at least 75% of the aggregate of (i) the total number of meetings of our Board of Directors held during the period for which he or she has been a director and (ii) the total number of meetings held by all committees of our Board of Directors on which he or she served during the periods that he or she served.

The names of our director nominees and directors, their ages and certain other information about them are set forth below:

Name Age Position

Robert W. Duggan 79 Chief Executive Officer and Executive Chairman

Mahkam Zanganeh 53 Chief Executive Officer, President, and Director

Manmeet S. Soni 46 Chief Operating Officer and Director

Kenneth A. Clark 65 Lead Independent Director

Robert Booth 70 Director

Alessandra Cesano 63 Director

Ujwala Mahatme 59 Director

Yu Xia 57 Director

The principal occupations and positions and directorships for at least the past five years of our directors and director nominees, as well as certain information regarding their individual experience, qualifications, attributes and skills that led our Board of Directors to conclude that they should serve on the Board of Directors, are described below. There are no family relationships among any of our directors or executive officers, however, Mr. Duggan and Dr. Zanganeh have a personal relationship with each other.

Robert W. Duggan, age 79, has served as a member of our Board of Directors since December 2019, Executive Chairman since February 2020, and Chief Executive Officer since April 2020. Since 2016, Mr. Duggan has been Chief Executive Officer of Duggan Investments, Inc., a family office of Mr. Duggan dedicated to research and administration of his personal investments primarily in the field of biotech focused on patient-friendly breakthrough solutions to complex diseases of aging. From September 2007 through the acquisition by AbbVie Inc. in May 2015, Mr. Duggan was a member of the board of directors of Pharmacyclics, Inc., a patient-friendly, science-based, employee-driven developer of small-molecule medicines for the treatment of cancers. Mr. Duggan was also the Chairman and Chief Executive Officer of Pharmacyclics from September 2008 to May 2015 as well as its largest investor. From 1990 to 2003, Mr. Duggan was chairman of the board of directors of Computer Motion, Inc. From 1997 to 2003, Mr. Duggan also served as Chief Executive Officer of Computer Motion. In June 2003, Computer Motion merged with Intuitive Surgical Inc. Mr. Duggan has been a director and the chairman of the board of directors of Pulse Biosciences, Inc. since November 2017. From 2003 to 2011, Mr. Duggan served on the board of directors of Intuitive Surgical. Mr. Duggan received a U.S. Congressman’s Medal of Merit from Ron Paul in 1985 and in 2000 he was named a Knight of the Legion of Honor by President Jacques Chirac of France. He is a member of the University of California at Santa Barbara Foundation board of trustees.

Mr. Duggan was appointed as a director because of his significant combined service as Chief Executive Officer of an innovative biopharmaceutical company and career spanning over 30 years as a venture investor and advisor for a broad range of companies, and extensive expertise in vision, strategic development, planning, finance and management.

Mahkam (Maky) Zanganeh, age 53, has served as a member of our Board of Directors since November 2020 and as Chief Executive Officer and President since July 2022. Dr. Zanganeh has previously served as the Company’s Chief Operations Officer from November 2020 to July 2022. Dr. Zanganeh is Founder, Chief Executive Officer and Director of Maky Zanganeh and Associates, an executive management and consulting firm founded in 2015. Previously, from August 2012 to September 2015, she served as the Chief Operating Officer of Pharmacyclics Inc. She also served as Chief of Staff and Chief Business Officer of Pharmacyclics from December 2011 to July 2012 and Vice President, Business Development from August 2008 to November 2011. Prior to joining Pharmacyclics Inc., Dr. Zanganeh served as President Director General (2007-2008) for the French government bio-cluster project initiative in France, establishing alliances and developing small life science businesses regionally. From September 2003 to August 2008, Dr. Zanganeh served as Vice President of Business Development for Robert W. Duggan & Associates. Dr. Zanganeh also served as worldwide Vice President of Training & Education (2002-2003) and President Director General for Europe, Middle East and Africa (1998-2002) for Computer Motion Inc. Dr. Zanganeh has been a member of the Board of Directors of Pulse Biosciences, Inc. since February 2017. Dr. Zanganeh received a DDS degree from Louis Pasteur University in Strasbourg, France and MBA from Schiller International University in France.

Dr. Zanganeh was appointed as a director because of her years of executive and operational experience in the life sciences industry.

Manmeet S. Soni, age 46, has served as a member of our Board of Directors since December 2019 and as Chief Operating Officer since October 2023. From February 2022 to October 2023, Mr. Soni was the President, Chief Operating Officer and Chief Financial Officer of Reata Pharmaceuticals, Inc., a pharmaceutical company focused on developing and commercializing novel therapeutics for the treatment of severe or life-threatening diseases, until its acquisition by Biogen in

October 2023. Mr. Soni joined Reata in August 2019 as Chief Financial Officer, Executive Vice President and was promoted in June 2020 to Chief Operating Officer and Chief Financial Officer, Executive Vice President of Reata.

Prior to joining Reata Pharmaceuticals, Mr. Soni was the Senior Vice President and Chief Financial Officer of Alnylam Pharmaceuticals Inc. from May 2017 to August 2019. From March 2016 to February 2017, Mr. Soni served as Executive Vice President, Chief Financial Officer and Treasurer of ARIAD Pharmaceuticals, Inc., a biopharmaceutical company, when ARIAD was acquired by Takeda Pharmaceutical Company Limited. Previously, he served as Chief Financial Officer of Pharmacyclics, Inc., a biopharmaceutical company, until its acquisition by AbbVie in 2015. Prior to joining Pharmacyclics, Mr. Soni worked at Zeltiq Aesthetics Inc., a publicly held medical technology company which was acquired by Allergan Inc. (acquired by Abbvie). Prior to Zeltiq, Mr. Soni worked at PricewaterhouseCoopers in the life science and venture capital group. Mr. Soni currently serves as a member of the board of directors of Pulse Biosciences, Inc. since November 2017 and previously served as a member of the board of directors of Arena Pharmaceuticals, Inc. (acquired by Pfizer, Inc.). Mr. Soni is a Certified Public Accountant and Chartered Accountant (India).

Mr. Soni was appointed as a director because of his extensive experience in the life sciences industry and his financial and accounting expertise.

Kenneth A. Clark, age 65, has served on our Board of Directors since October 2021. Mr. Clark is a partner of Wilson Sonsini Goodrich & Rosati, where he advises biotech companies on strategic partnerships, mergers and acquisitions, financing transactions and operational matters. He is also a partner of TCG Labs, a venture capital fund affiliated with The Column Group. Mr. Clark has previously served as a member of the boards of directors for multiple publicly traded companies, including Pulse BioSciences, Inc. and Pharmacyclics, Inc, and is currently a director of Acurex Biosciences. Mr. Clark received his undergraduate degree from Vanderbilt University and a juris doctorate from the University of Texas School of Law.

We believe Mr. Clark is qualified to serve on our Board of Directors because of his expertise in business consulting, deal transactions, financing, and corporate law in the biotechnology sector.

Robert Booth, age 70, has served on our Board of Directors since September 2022 and also serves as a member of the Audit Committee and the Nominating and Corporate Governance Committee. Dr. Booth has spent more than 30 years in the biopharmaceutical industry, most recently as founder and chief executive officer of Virobay Inc. Additionally, he has served as operating partner and senior advisor at TPG Biotech. Prior to Virobay, Dr. Booth was the chief scientific officer at Celera Genomics, where he was responsible for all discovery and development activities. At Celera, Dr. Booth conceived and initiated the BTK inhibitor program that was ultimately licensed to Pharmacyclics and from which IMBRUVICA® (ibrutinib) was developed and approved. Dr. Booth served on the board of directors of Pharmacyclics until its acquisition by AbbVie. Prior to Celera, Dr. Booth was senior vice president for Roche in Palo Alto, California, where he was a member of the global research management team and the business development committee, which oversaw licensing opportunities. Dr. Booth additionally currently serves on the boards of Acurex Biosciences and Thryv Therapeutics, private companies that are focused on neurodegenerative diseases and cardiovascular diseases, respectively. Dr. Booth received his BSc and PhD in biochemistry from the University of London. The Board has determined that Dr. Booth qualifies as an independent director under applicable Nasdaq listing rules.

We believe Dr. Booth is qualified to serve on our Board of Directors because of his expertise in the life sciences industry.

Ujwala Mahatme, age 59, has served as a member of our Board of Directors since July 2020. Currently, Ms. Mahatme serves as the Founder and Managing Partner of Mahatme Bitterman PLLC, a role she has held since 2002. Previously, Ms. Mahatme served as Counsel at Gibson, Dunn & Crutcher and Counsel and Associate at Pillsbury Winthrop Shaw Pittman LLP. She received her Bachelor of Commerce from Brihan Maharashtra College of Commerce, University of Poona, her Bachelor of Laws from ILS Law School, University of Poona, Master of Laws from the University of Cambridge and Master of Laws in Corporation Law from New York University.

We believe Ms. Mahatme is qualified to serve on our Board of Directors because of her expertise in corporate law and financing in the biotechnology sector.

Alessandra Cesano, age 63, has served as a member of our Board of Directors and the Nominating and Corporate Governance Committee since November 2022. Dr. Cesano has 26 years of experience in research and development in both drug and diagnostic companies ranging from large, global biopharma to private, venture-backed companies, and currently serves as

Chief Medical Officer of ESSA Pharma. Prior to ESSA, Dr. Cesano was the Chief Medical Officer at NanoString Inc., where she built and led the Immuno-Oncology program and the diagnostic pipeline. Prior to NanoString, she was Chief Medical Officer for Cleave Biosciences. There, Dr. Cesano led the successful filing of two INDs for a clinical candidate and led two Phase I trials in Multiple Myeloma and solid tumors. Dr. Cesano has global full-phase development and regulatory experience with large and small molecules and had a substantive and lead role in two approved drugs – Kepivance® (palifermin) and Vectibix® (panitumumab). Dr. Cesano serves on the board of directors at Puma Biotechnology. She received her PhD in tumor immunology and her MD from the University of Turin. The Board has determined that Dr. Cesano qualifies as an independent director under applicable Nasdaq listing rules.

We believe Dr. Cesano is qualified to serve on our Board of Directors because of her expertise in the biopharmaceutical industry focused on oncology.

Yu (Michelle) Xia, age 57, has served as a member of our Board of Directors since January 2023. Dr. Xia is the founder of Akeso, Inc., and has been the chairwoman, president and CEO of the Company since its inception in 2012.

Dr. Xia has over 27 years of experience in the pharmaceutical industry and academic research. Prior to founding Akeso Biosciences, Dr. Xia held senior leadership roles at Crown Bioscience Inc., where she played a decisive role in constructing Crown Bioscience’s platform, building its team, setting and implementing its strategies, and forging its joint venture with Pfizer (the Pfizer-Crown Asian Cancer Research Centre). From 2006 to 2008, Dr. Xia served as a senior scientist and group leader at PDL BioPharma, Inc. (later acquired by AbbVie). In 2006, Dr. Xia served as a senior process development scientist at Bayer Corporation in the U.S. At both PDL BioPharma and Bayer, Dr. Xia oversaw CMC, process development and manufacturing of therapeutic protein and antibody drugs. Dr. Xia began her pharmaceutical career at Axys Pharmaceuticals, Inc. (later acquired by Celera Genomics), where she held both scientific and managerial roles in drug discovery programs from December 2000 to December 2005, overseeing a broad range of activities from target validation through IND-enabling studies. Dr. Xia earned her Ph.D. degree in molecular biology and microbiology from Newcastle University in the U.K. in 1994. Dr. Xia completed her postdoctoral research training at the University of Glasgow in the U.K. from 1993 to 1996, and she also conducted the cancer immune therapy research at the University of Louisville School of Medicine in the U.S. from 1996 to 2000.

Over the years, Dr. Xia has served important roles in numerous influential organizations, including a member of the Special Committee for Monoclonal Antibody of the China Medicinal Biotech Association, a committee member of the Special Committee for Science and Technology Innovation of China Overseas Returnee Entrepreneur Investment Association, an advisory committee member of the Chinese Antibody Society, and a director of Tongxieyi Antibody Talent Club. Dr. Xia has also received numerous awards and recognitions for her contributions to both the pharmaceutical industry and commercial enterprises. Most recently, Dr. Xia was selected into Forbes’ Powerful Women in Technology in 2020 and in 2023 was named by Forbes China as a Top 100 Women in Business in China.

We believe Dr. Xia is qualified to serve on our Board of Directors because of her extensive experience in the biopharmaceutical industry, including in oncology.

Board Committees

Our Board of Directors has the following standing committees: Audit Committee, Compensation Committee, and Nominating and Corporate Governance Committee, each of which has the composition and the responsibilities described below. The Audit Committee, Compensation Committee, and Nominating and Corporate Governance Committee all operate under charters approved by our Board of Directors, which charters are available on the Investor Center of our website at https://www.smmttx.com under “Corporate Governance.” Our Board of Directors from time to time establishes additional committees to address specific needs.

The following table sets forth (i) the three standing committees of the Board of Directors, (ii) the members of each committee as of December 31, 2023, and (iii) the number of meetings held by each committee in fiscal year 2023:

Name of Director Audit Compensation Nominating and Corporate Governance

Robert W. Duggan

Mahkam Zanganeh

Manmeet S. Soni(1)

Kenneth A. Clark(1) X (Chair) X (Chair)(2) X (Chair)

Robert Booth X X

Alessandra Cesano X

Ujwala Mahatme X X X

Number of Meetings Held During 2023 5 2 1

_______________

(1)On October 13, 2023, the Company appointed Manmeet Soni as Chief Operating Officer. In connection with his employment as Chief Operating Officer, Mr. Soni resigned from his seat on the Board’s Audit Committee, Compensation Committee and Nominating and Corporate Governance Committee, as well as from his position as lead independent director. To fill the vacancies left by Mr. Soni, Robert Booth was appointed to the Audit Committee and Kenneth A. Clark was appointed as the lead independent director on the Board.

(2)On February 16, 2024, Mr. Clark was appointed to serve as Compensation Committee Chair.

Our Corporate Governance Guidelines set out that all directors are expected to attend our annual meeting of stockholders. All of the current Board members who were members of the Board at our 2023 annual stockholder meeting attended such meeting.

Audit Committee

Our Audit Committee oversees our corporate accounting and financial reporting process and assists the Board of Directors in monitoring our financial systems and our legal and regulatory compliance. Our Audit Committee is responsible for, among other things:

•appointing, approving the compensation of, and assessing the independence of our registered public accounting firm;

•overseeing the work of our registered public accounting firm, including through the receipt and consideration of reports from such firm;

•reviewing and discussing with management and the registered public accounting firm our annual and quarterly financial statements and related disclosures;

•monitoring our internal control over financial reporting, disclosure controls and procedures and code of business conduct and ethics;

•establishing policies regarding the receipt and retention of accounting related complaints and concerns;

•meeting independently with our internal auditing staff, if any, our registered public accounting firm and management;

•reviewing and approving or ratifying any related person transactions; and

•preparing the Audit Committee report required by SEC rules.

The members of our Audit Committee are Mr. Clark, Mr. Booth and Ms. Mahatme. Mr. Clark serves as our Audit Committee Chair. Our Board of Directors has determined that each member of our Audit Committee is independent within the meaning of the independent director guidelines of The Nasdaq Stock Market. We believe that the composition of our Audit Committee meets the requirements for independence under, and the functioning of our Audit Committee complies with, all applicable requirements of The Nasdaq Stock Market and SEC rules and regulations. In addition, our Board of Directors has determined that Mr. Clark meets the financial literacy requirements under the rules of The Nasdaq Stock Market and the SEC and that he qualifies as Audit Committee financial expert as defined under SEC rules and regulations.

Compensation Committee

Our Compensation Committee oversees our corporate compensation policies, plans and programs. Our Compensation Committee is responsible for, among other things:

•reviewing and approving, or making recommendations to our Board of Directors with respect to, the compensation of our chief executive officers and our other executive officers;

•overseeing an evaluation of our senior executives;

•overseeing and administering our cash and equity incentive plans;

•reviewing and making recommendations to our Board of Directors with respect to director compensation;

•reviewing and discussing annually with management our “Compensation Discussion and Analysis” disclosure if and to the extent then required by SEC rules; and

•preparing the Compensation Committee report required by SEC rules.

The members of our Compensation Committee are Mr. Clark and Ms. Mahatme. Mr Clark serves as our Compensation Committee Chair. Our Board of Directors has determined that each member of our Compensation Committee is independent within the meaning of the independent director guidelines of The Nasdaq Stock Market. We believe that the composition of our Compensation Committee meets the requirements for independence under, and the functioning of our Compensation Committee complies with, all applicable requirements of The Nasdaq Stock Market and SEC rules and regulations.

Nominating and Corporate Governance Committee

Our Nominating and Corporate Governance Committee oversees and assists our Board of Directors in reviewing and recommending corporate governance policies and nominees for election to our Board of Directors. Our Nominating and Corporate Governance Committee is responsible for, among other things:

•identifying individuals qualified to become members of our Board of Directors;

•recommending to our Board of Directors the persons to be nominated for election as directors and to each of our Board of Directors’ committees;

•reviewing and making recommendations to our Board of Directors with respect to our Board of Directors leadership structure;

•reviewing and making recommendations to our Board of Directors with respect to management succession planning;

•developing and recommending to our Board of Directors corporate governance principles; and

•overseeing an annual evaluation of our Board of Directors.

As of December 31, 2023 the members of our Nominating and Corporate Governance Committee are Mr. Clark, Dr. Booth, Ms. Mahatme and Dr. Cesano. Mr. Clark serves as our Nominating and Corporate Governance Committee Chair. Our Board of Directors has determined that each member of our Nominating and Corporate Governance Committee is independent within the meaning of the independent director guidelines of The Nasdaq Stock Market.

Director Compensation

Employee directors are not compensated for Board of Directors services in addition to their regular employee compensation.

For 2023, the non-employee members of the Board of Directors were compensated as follows:

Cash compensation: Each non-employee member of the Board received the following cash compensation (the “Retainer Cash Payments”):

•an annual retainer for each member of the Board of $48,000 paid in equal quarterly installments;

•the members of our Audit, Compensation and Nominating and Corporate Governance Committees were eligible to receive an additional annual retainer of $6,500 for their service on each committee; and

•the Chairs of the Audit, Compensation and Nominating and Corporate Governance Committees were eligible to receive annual retainers of $36,700, $13,000, and $13,000, respectively.

We reimbursed our non-employee directors for all reasonable out-of-pocket expenses incurred in the performance of their duties as directors.

Equity Compensation: Each non-employee director received a stock option annual grant to purchase 35,000 shares of the Company’s common stock, par value $0.01, at a strike price equal to the fair market value of the common stock on the grant date, which shall vest in four equal quarterly installments, with the first such installment occurring on March 31 in the year of grant.

Each new non-employee director appointed during 2023 received a stock option grant to purchase 200,000 shares of the Company’s common stock, par value $0.01, at a strike price equal to the fair market value of the common stock on the grant

date, which shall vest in four equal annual installments, with the first such installment occurring on the one-year anniversary of the grant date. Each new non-employee director appointed during 2023 was also granted a prorated annual grant for their service in the fourth quarter of 2023, at a strike price equal to the fair market value of the common stock on the grant date, which vested in full on December 31, 2023.

For 2023, each non-employee director may elect to convert all or a portion of his or her Retainer Cash Payments into a number of options (the “Retainer Option,” and such election, a “Retainer Option Election”) into a set number of options. The number of shares subject to a Retainer Option will be equal to (i) the product of (A) the dollar value of the aggregate Retainer Cash Payments that the non-employee director elects to forego over the course of a specified period covered by a Retainer Option Election in favor of receiving a Retainer Option multiplied by (B) 3.0 (the “Retainer Option Multiplier”), divided by (ii) the fair market value of a share on the date of grant of the Retainer Option, provided that the number of shares covered by such Retainer Option shall be rounded to the nearest whole share. The Retainer Options shall be awarded annually and vest in four equal quarterly installments on March 31, June 30, September 30 and December 31 following the Retainer Option Election, subject to the director remaining as a non-employee director on each such vesting date. The election must have been made by December 31 of the preceding year.

The following table sets forth information concerning compensation paid or earned for services rendered to us by the non-employee members of our Board of Directors for the fiscal year ended December 31, 2023. Compensation paid to Mr. Duggan, Dr. Zanganeh and Mr. Soni is included in the section entitled, “Executive Compensation” and excluded from the table below:

Name Fees Earned or Paid in Cash ($) Option Awards ($)(1) Total ($)

Michelle Xia(3) — — —

_______________

(1)Amounts shown represent the aggregate grant date fair value of the option awards computed in accordance with FASB ASC Topic 718. These amounts do not correspond to the actual value that will be realized by our directors. The assumptions used in the valuation of these awards are consistent with the valuation methodologies specified in the notes to our financial statements.

(2)Fees earned or paid in cash for Mr. Clark and Mr. Booth were a result of these individuals filling the vacancies left by Mr. Soni as described above.

(3)Dr. Xia did not receive any compensation for her role as a member of the Company's Board of Directors in 2023.

The aggregate number of shares subject to stock options outstanding and exercisable on December 31, 2023 for each non-employee director is as follows:

Michelle Xia — —

DELINQUENT SECTION 16(a) REPORTS

Section 16(a) of the Exchange Act requires that our executive officers and directors and other persons who beneficially own more than 10% of a registered class of our equity securities file with the SEC reports of ownership and reports of changes in ownership of shares and other equity securities. Such executive officers and directors and other persons who beneficially

own more than 10% of a registered class of our equity securities are required by the SEC to furnish us with copies of all Section 16(a) reports filed by such reporting persons.

Based solely on our review of such forms furnished to us or written representations provided to us by the reporting person, we are aware of no late Section 16(a) reports required to be filed by our executive officers, directors and other persons who beneficially own more than 10% of a registered class of our equity securities in the year ended December 31, 2023, other than: (i) a late Form 4 to report the acquisition by Akeso of 10,000,000 shares of common stock on January 17, 2023 in connection with the entry into the License Agreement; and (ii) a late Form 4 to report the acquisition by Akeso of 21,523,530 shares of common stock on March 7, 2023 in the Company’s 2023 Rights Offering. Dr. Xia is a stockholder and exercises the right to vote approximately 28.9% of Akeso's ordinary shares, and serves as chairwoman, president and chief executive officer of Akeso. Dr. Xia disclaims beneficial ownership of the shares of Issuer's Common Stock beneficially owned by Akeso, except to the extent of her pecuniary interest therein. Dr. Xia filed a Form 5 on February 14, 2024 to report each of the transactions described in clauses (i) and (ii) of this paragraph.

Item 11. Executive Compensation

EXECUTIVE COMPENSATION

Compensation Committee Report

The information contained in the following report of the Compensation Committee shall not be deemed to be “soliciting material” or to otherwise be considered “filed” with the SEC, nor shall such information be incorporated by reference into any future filing under the Securities Act of 1933, as amended (the “Securities Act”), or the Exchange Act except to the extent that the Company specifically incorporates it by reference into such filing.

The Compensation Committee has reviewed and discussed the following “Executive Compensation” section of this Annual Report with management. Based on this review and discussion, the Compensation Committee recommended to our Board of Directors that such information be included in this Annual Report.

Members of the Compensation Committee:

Kenneth A. Clark (Chair)

Ujwala Mahatme

Executive Compensation

The following is a discussion and analysis of compensation arrangements of our named executive officers (NEOs). This discussion contains forward looking statements that are based on our current plans, considerations, expectations and determinations regarding future compensation programs. Actual compensation programs that we adopt may differ materially from currently planned programs as summarized in this discussion. As a smaller reporting company, we are not required to include a Compensation Discussion and Analysis section and have elected to comply with the scaled disclosure requirements applicable to smaller reporting companies.

We seek to ensure that the total compensation paid to our executive officers is reasonable and competitive. Compensation of our executives is structured around the achievement of individual performance and near-term corporate targets as well as long-term business objectives.

Our NEOs for fiscal year 2023 were as follows, who are comprised of (1) our principal executive officers in fiscal year 2023 and (2) our next most highly compensated executive officers who were serving as executive officers as of December 31, 2023:

•Robert W. Duggan, our Chief Executive Officer and Executive Chairman;

•Mahkam Zanganeh, our Chief Executive Officer, President and Director;

•Manmeet Soni, our Chief Operating Officer and Director

•Ankur Dhingra, our Chief Financial Officer;

Summary Compensation Table

The following table provides information regarding the compensation of our principal executive officers and our next two most highly compensated executive officers, who were serving as executive officers as of December 31, 2023:

_______________

(1) Final bonus amounts for 2023 have not yet been approved by the Compensation Committee and will be paid in April 2024.

(2) Amounts shown represent the aggregate grant date fair value of the option awards computed in accordance with FASB ASC Topic 718. These amounts do not correspond to the actual value that will be realized by our named executive officers. The assumptions used in the valuation of these awards are consistent with the valuation methodologies specified in the notes to our financial statements.

(3) The amounts paid for all other compensation consisted of the following:

Robert W. Duggan,Chief Executive Officer and Executive Chairman(3) 2023 — — — —

(4) Mr. Duggan has declined any compensation from the Company.

(5) Dr. Zanganeh’s salary was increased to from $450,000 per annum to $600,000 per annum effective January 1, 2023.

(6) Mr. Dhingra’s salary was increased from $450,000 per annum to $500,000 per annum effective January 1, 2023.

(7) Dr. Zanganeh was awarded 11,988,198 of options which vest in four equal annual installments, with an aggregate fair value associated at the date of grant date of $16,524,442. Dr. Zanganeh was also awarded 11,988,198 of stock options with performance-based criteria and market service conditions with an aggregate fair value at the grant date of $16,903,359, assuming 100% of the performance conditions are achieved. Only 20% of these awards were estimated to be probable at December 31, 2023 and these awards have a fair value associated with the awards at the date of grant of $3,380,673.

(8) Dr. Zanganeh was awarded stock options with performance-based criteria and market service conditions with an aggregate fair value at the grant date of $1,384,400, assuming 100% of the performance conditions are achieved. Only

20% of the awards were estimated to be probable at December 31, 2023 and these awards have a fair value associated with the awards at grant date of $307,200.

(9) Mr. Soni was awarded 14,000,000 stock options which vest in four equal annual installments, with an aggregate fair value associated at the date of grant date of $19,297,495. Mr Soni was also awarded 14,000,000 stock options with performance-based criteria and market service conditions with an aggregate fair value at the grant date of $19,740,000, assuming 100% of the performance conditions are achieved. Only 20% of these awards were estimated to be probable at December 31, 2023 and these awards have a fair value associated with the awards at the date of grant of $3,948,000. Prior to joining the Company as Chief Operating Officer, Mr. Soni was granted options for serving on the Company's Board of Directors with a fair value of $136,145.

(10) Mr. Dhingra was awarded 600,000 of options which vest in four equal annual installments, with an aggregate fair value associated at the date of grant date of $563,064. Mr Soni was also awarded 750,000 of stock options with performance-based criteria and market service conditions with an aggregate fair value at the grant date of $587,600, assuming 100% of the performance conditions are achieved. Only 20% of these awards were estimated to be probable at December 31, 2023 and these awards have a fair value associated with the awards at the date of grant of $131,400.

Outstanding Equity Awards at Fiscal Year-End

The following table presents certain information concerning equity awards held by our principal executive officer and our next most highly compensated executive officer, who were serving as executive officers as of December 31, 2023:

Option Awards

Grant date Exercisable Unexercisable

Robert W. Duggan, Chief Executive Officer and Executive Chairman — — — — —

_______________

(1) Option award was originally a performance-based award. In September 2021, this award was modified to a time-based award, which vest in four equal annual installments beginning on November 22, 2021.

(2) Options vest in three years on December 15, 2024.

(3) Option award is a performance-based award with market service conditions. As of December 31, 2023, none of the conditions had been met.

(4) Options vest in four equal quarterly installments.

(5) Options vest in four equal annual installments beginning May 31, 2023.

(6) On October 13, 2023, the Company appointed Manmeet Soni as Chief Operating Officer. Awards granted prior to October 13, 2023 were for Mr. Soni’s service on the Company’s Board of Directors.

Narrative to Summary Compensation Table and Outstanding Equity Awards at Fiscal Year End

Employment Agreement with Mahkam Zanganeh

We entered into an employment agreement with Dr. Zanganeh, our current Chief Executive Officer and President, on November 22, 2020. The employment relationship between the Company and Dr. Zanganeh is “at-will”, and the employment agreement has no specific term. Dr. Zanganeh’s annual base salary as of December 31, 2022 was $450,000. Pursuant to her employment agreement, upon her appointment she received a grant of options to purchase 2,400,000 shares of our common stock, vesting in four equal annual installments, subject to the satisfaction of certain performance conditions. During fiscal year ended December 31, 2021, the Compensation Committee of the Board of Directors determined to eliminate the requirements for satisfying performance-based stock option awards and deemed all performance-based vesting requirements satisfied. Following this determination, the option awards are subject only to previous existing time-based vesting conditions. Dr. Zanganeh was eligible for an annual target bonus equal to 45% of her salary in 2021 and 2022 and 60% of her annual base salary for 2023, subject to achievement of performance objectives. Dr. Zanganeh was paid a discretionary cash bonus of $182,250 relating to 2021 and this bonus was paid in March of 2022. Dr. Zanganeh was paid a discretionary cash bonus of $202,500 and an extraordinary bonus of $250,000 relating to 2022 and this bonus was paid in January 2023. Dr. Zanganeh’s salary was increased to from $450,000 per annum to $600,000 per annum effective January 1, 2023.

Dr. Zanganeh is eligible to participate in employee benefit plans maintained from time to time by us of general applicability to other senior executives. During her term of service as an executive officer, Dr. Zanganeh will not receive compensation that would otherwise be owed to her in her capacity as a member of our Board of Directors.

Employment Agreement with Manmeet Soni

We entered into an employment agreement with Mr. Soni, our Chief Operating Officer on October 13, 2023. The employment relationship between the Company and Mr. Soni is “at-will”, and the employment agreement has no specific term. Mr. Soni’s annual base salary as of December 31, 2023 was $600,000. Pursuant to his employment agreement upon his appointment he received a grant of options to purchase 14,000,000 shares of our common stock, vesting in four equal annual installments. In addition, Mr. Soni received a performance-based grant of options to purchase 14,000,000 shares of our common stock, vesting annually over four years, subject to the satisfaction of certain performance and market service conditions. Mr. Soni will be eligible for a yearly discretionary cash bonus in an amount solely determined by the Company of up to 60% of annual base salary.

Employment Agreement with Ankur Dhingra

We entered into an employment letter with Mr. Dhingra, our Chief Financial Officer, on April 15, 2022. The employment relationship between the Company and Mr. Dhingra is “at-will”, and the employment agreement has no specific term. Mr. Dhingra’s annual base salary as of December 31, 2023 was $500,000. Pursuant to his employment agreement, upon his appointment he received a grant of options to purchase 600,000 shares of our common stock, vesting in four equal annual installments on the date approved by the Compensation Committee, and then on the next three anniversaries of such date. Mr. Dhingra was eligible in 2022 for an annual target bonus equal to 50% of his annual base salary, payable in accordance with the Company’s normal payroll practices. Mr. Dhingra was paid a discretionary cash bonus of $131,918 and an extraordinary bonus of $250,000 relating to 2022 and this bonus was paid in January 2023. Mr. Dhingra’s salary was increased from $450,000 per annum to $500,000 per annum effective January 1, 2023.

Mr. Dhingra is eligible to participate in employee benefit plans maintained from time to time by us of general applicability to other senior executives.

PAY VERSUS PERFORMANCE

As required by Section 953(a) of the Dodd-Frank Wall Street Reform and Consumer Protection Act and Item 402(v) of Regulation S-K, we are providing the following information about the relationship between executive

compensation and certain financial performance of our Company. The disclosure included in this section is prescribed by SEC rules and does not necessarily align with how the Company or the compensation committee view the link between the Company’s performance and its NEOs pay.

Item 12. Security Ownership of Certain Beneficial Owners and Management and Related Stockholder Matters

SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT

The following table sets forth certain information as of February 9, 2024 with respect to the beneficial ownership of our common stock by (i) each person we believe beneficially holds more than 5% of the outstanding shares of our common stock based solely on our review of SEC filings or information provided to us by such person; (ii) each director and nominee; (iii) each named executive officer listed in the table entitled, “Summary Compensation Table” under the section entitled, “Executive Compensation”; and (iv) all directors and executive officers as a group. As of February 9, 2023, 701,697,179 shares of our common stock were issued and outstanding. Unless otherwise indicated, all persons named as beneficial owners of our common stock have sole voting power and sole investment power with respect to the shares indicated as beneficially owned. Unless otherwise noted below, the address of each stockholder listed on the table is c/o Summit Therapeutics Inc., 601 Brickell Key Drive, Suite 1000, Miami, FL 33131.

5% Stockholders:

Named executive officers and directors:

_______________

(*) Represents beneficial ownership of less than 1% of the outstanding shares of our common stock.

(1) Excludes shares that may be acquired through the exercise of outstanding stock options or other equity awards.

(2) Represents shares issuable within 60 days after February 9, 2024 upon exercise of exercisable options and warrants; however, unless otherwise indicated, these shares do not include any equity awards awarded after February 9, 2024.

(3) For purposes of calculating the Percent of Class, shares that the person or entity had a right to acquire within 60 days after February 9, 2024 are deemed to be outstanding when calculating the Percent of Class of such person or entity.

(4) This information is based upon a Schedule 13D/A filed by Mr. Duggan with the Securities and Exchange Commission on February 16, 2023, updated by a Form 4 filed by Mr. Duggan on January 4, 2024, and information known to the Company. The 552,372,797 shares of common stock beneficially owned by Mr. Duggan includes (i) 548,369,106 shares of common stock, 9,346,434 shares of common stock, representing the number of shares of common stock issued to Mr. Duggan as payment of interest in connection with the Note Purchase Agreement, (ii) warrants to purchase 3,985,055 shares of common stock, which are exercisable until December 24, 2029 and (iii) options to purchase 18,636 shares of Common Stock, comprised of 18,636 options (exercisable beginning on March 31, 2024 and exercisable until January 2, 2034).

(5) This information is based upon a Schedule 13D/A filed by Dr. Zanganeh with the Securities and Exchange Commission on March 13, 2023, updated by a Form 4 filed by and information known to the Company. The 37,537,392 shares of Common Stock beneficially owned consist of (i) 35,268,388 shares of Common Stock owned in the aggregate by the Mahkam Zanganeh Revocable Trust and the Shaun Zanganeh Irrevocable Trust, (ii) warrants to purchase 315,681 shares of Common Stock (exercisable until December 24, 2029), and (iii) options to purchase 1,953,323 shares of Common Stock, comprising of 153,323 options (exercisable beginning on December 31, 2020 and exercisable until November 11, 2030) and 1,800,000 options (exercisable beginning on November 22, 2021 and exercisable until November 22, 2030). Of the warrants to purchase 315,681 shares of Common Stock, 315,681 are held by the Shaun Zanganeh Irrevocable Trust. The options to purchase 1,953,323 shares of Common Stock are held individually by Dr. Zanganeh.

(6) The shares beneficially owned by Dr. Xia include (i) 31,520,000 shares of Common Stock owned by Akeso, a company in which Dr. Xia is a stockholder and exercises the right to vote approximately 28.9% of Akeso’s ordinary shares, and in which Dr. Xia serves as chairwoman, president and chief executive officer, and (ii) options to purchase 8,750 shares of Common Stock held individually by Dr. Xia. Dr. Xia disclaims beneficial ownership of all shares of Common Stock held by Akeso, except to the extent of her pecuniary interest therein.

(7) This information is based upon a Form 4 filed by Mr. Soni with the securities and Exchange Commission on October 16, 2023 and information known to the Company. The 3,370,909 shares of common stock beneficially owned by Mr. Soni includes 2,976,190 shares acquired in the private placement on October 13, 2023.

(8) This information is based upon a Form 4 filed by Mr. Dhingra with the Securities and Exchange Commission on December 13, 2023 and information known to the Company. The 444,485 shares of common stock beneficially owned by includes (i) 39,527 shares of common stock directly owned and (ii) 254,958 shares of common stock indirectly held by the Dhingra Family Revocable Trust.

EXECUTIVE OFFICERS

Biographical data for our current executive officers, including their ages as of December 31, 2023 is set forth below, except Mr. Duggan’s, Dr. Zanganeh and Mr. Soni’s biography, each of which are included under the heading, “Board of Directors and Committees of the Board” above.

Ankur Dhingra, age 48, has served as Chief Financial Officer since May 2022. Mr. Dhingra served as Chief Financial Officer at CareDx, a company focused on transplant patient journey, from March 25, 2021 through May 25, 2022. In his role at CareDx, Mr. Dhingra was responsible for finance, information technology and market access functions. Prior to CareDx, Mr. Dhingra spent 18 years at Agilent Technologies (“Agilent”) in various finance and business management roles. From January 2019 through March 2021, he was Vice President of Investor Relations and prior to that, Mr. Dhingra served as Group CFO for Agilent’s Life Sciences and Applied Markets business. Mr. Dhingra has demonstrated a track record of success scaling businesses by executing and influencing growth-oriented business strategies, expanding margins and deploying M&A policies. He has extensive experience managing global teams of finance and accounting professionals. Mr. Dhingra is a qualified Chartered Accountant (India).

Equity Compensation Plan Information

The following table presents information about our equity compensation plans as of December 31, 2023:

Equity compensation plans not approved by security holders (2) 69,973 $ 1.44 —

_______________

(1) Includes the following plans: the 2020 Stock Incentive Plan (the “Stock Incentive Plan”), the 2016 Long Term Incentive Plan (the “LTIP”) and the 2005 EMI Scheme Rules (the “EMI Plan” and together with the LTIP, the “Legacy Plans”). Our Stock Incentive Plan provides that the number of shares available for issuance thereunder will be increased on the first day of each fiscal year beginning with the 2021 fiscal year in an amount equal to the least of (i) 6,400,000 shares, (ii) 4% of the outstanding shares of our common stock as of such date, or (iii) such number of shares as determined by our Board of Directors. On January 1, 2024, the number of shares available for issuance under the Stock Incentive Plan increased by 6,400,000 shares pursuant to these provisions. This increase is not reflected in the table above. On September 18, 2020, the Company became the successor issuer to Summit Therapeutics plc (“Old Summit”), at which point the Company assumed Old Summit’s obligations under our Legacy Plans and replaced all equity awards granted under the Legacy Plans with equivalent equity awards for our common stock. Excludes shares issued under the 2020 Employee Stock Purchase Plan.

(2) Includes outstanding warrants granted to Elaine Stracker for consultancy services provided to the Company pursuant to the Company’s consultancy agreement that was terminated by mutual agreement in June 2020.

Item 13. Certain Relationships and Related Party Transactions

CERTAIN RELATIONSHIPS AND RELATED PARTY TRANSACTIONS

Our Board of Directors has adopted written policies and procedures for the review of any transaction, arrangement or relationship in which the Company is a participant, the amount involved exceeds $120,000, and one of our executive officers, directors, director nominees or 5% stockholders (or their immediate family members), each of whom we refer to as a “related person,” has a direct or indirect material interest. If a related person proposes to enter into such a transaction, arrangement or relationship, which we refer to as a “related person transaction,” the related person must report the proposed related person transaction to our Chief Executive Officers or principal financial officer. The policy calls for the proposed related person transaction to be reviewed and, if deemed appropriate, approved by our Audit Committee. Whenever practicable, the reporting, review and approval will occur prior to entry into the transaction. If advance review and approval is not practicable, the Audit Committee will review, and, in its discretion, may ratify the related person transaction. The policy also permits the Chair of the Audit Committee to review and, if deemed appropriate, approve proposed related person transactions that arise between Audit Committee meetings, subject to ratification by the Audit Committee at its next meeting. Any related person transactions that are ongoing in nature will be reviewed annually.

A related person transaction reviewed under the policy will be considered approved or ratified if it is authorized by the Audit Committee after full disclosure of the related person’s interest in the transaction. As appropriate for the circumstances, the Audit Committee will review and consider:

•the related person’s interest in the related person transaction;

•the approximate dollar value of the amount involved in the related person transaction;

•the approximate dollar value of the amount of the related person’s interest in the transaction without regard to the amount of any profit or loss;

•whether the transaction was undertaken in the ordinary course of our business;

•whether the terms of the transaction are no less favorable to us than terms that could have been reached with an unrelated third party;

•the purpose of, and the potential benefits to us of, the transaction; and

•any other information regarding the related person transaction or the related person in the context of the proposed transaction that would be material to investors in light of the circumstances of the particular transaction.

The Audit Committee may approve or ratify the transaction only if the Audit Committee determines that, under all of the circumstances, the transaction is in the best interests of the Company and its stockholders. The Audit Committee may impose any conditions on the related person transaction that it deems appropriate.

In addition to the transactions that are excluded by the instructions to the SEC’s related person transaction disclosure rule, our Board of Directors has determined that the following transactions do not create a material direct or indirect interest on behalf of related persons and, therefore, are presumed not to be related person transactions for purposes of this policy:

•interests arising solely from the related person’s position as an executive officer of another entity (whether or not the person is also a director of such entity), that is a participant in the transaction, where (a) the related person and all other related persons own in the aggregate less than a 10% equity interest in such entity, (b) the related person and his or her immediate family members are not involved in the negotiation of the terms of the transaction and do not receive any special benefits as a result of the transaction, and (c) the amount involved in the transaction equals less than the greater of $200,000 or 5% of the annual gross revenues of the entity receiving payment under the transaction; and

•a transaction that is specifically contemplated by provisions of our charter or Bylaws.

The policy provides that transactions involving compensation of executive officers shall be reviewed and approved by our Compensation Committee in the manner specified in its charter.

Related Party Transactions

In addition to the compensation arrangements, including employment, termination of employment and change in control arrangements discussed above in the sections titled “Director Compensation” and “Executive Compensation,” we describe below transactions and series of similar transactions, since the beginning of our last fiscal year, to which we were a party or will be a party, in which:

•the amounts involved exceeded or will exceed $120,000; and

•any of our directors, nominees for director, executive officers or holders of more than 5% of our outstanding capital stock, or any immediate family member of, or person sharing the household with, any of these individuals or entities, had or will have a direct or indirect material interest.

Transactions with Robert W. Duggan

On December 6, 2022, the Company entered into a Note Purchase Agreement (the “Note Purchase Agreement”), with Mr. Duggan and Dr. Zanganeh, pursuant to which the Company agreed to sell to each of Mr. Duggan and Dr. Zanganeh unsecured promissory notes in the aggregate amount of $520 million. Pursuant to the Note Purchase Agreement, the Company issued to Mr. Duggan and Dr. Zanganeh unsecured promissory notes in the amount of $400 million (the “Duggan February Note”) and $20 million (the “Zanganeh Note”), respectively, which matured and became due on February 15, 2023 and an unsecured promissory note to Mr. Duggan in the amount of $100 million (the “Duggan September Note” and together with the Duggan February Note and the Zanganeh Note, the “December 2022 Notes”), which was originally due on September 15, 2023. The maturity dates of the December 2022 Notes could have been extended one or more times at the Company’s election, but in no event to a date later than September 6, 2024. In addition, if the Company consummates a public offering, then upon the later to occur of (i) five business days after the Company receives the net cash proceeds therefrom or (ii) May 15, 2023, the Duggan February Note and the Zanganeh Note shall be prepaid by an amount equal to the lesser of (a) 100% of the amount of the net proceeds of such offering and (b) the outstanding principal amount on such notes.

On January 19, 2023, the Company provided notice to extend the term of the Duggan February Note and Duggan September Note to a maturity date of September 6, 2024. Furthermore, on January 19, 2023, the Company and Mr. Duggan rectified the Duggan February Note and Duggan September Note in order to correctly reflect the parties’ intent that the

Company may only prepay (i) the Duggan February Note following the completion of a public rights offering to be conducted by Summit in the approximate amount of $500 million (the “2023 Rights Offering”), or a similar capital raise, in an amount equal to the lesser of (x) the net proceeds of the Rights Offering or such capital raise or (y) the full amount outstanding of the Duggan February Note, and (ii) the Duggan September Note following the completion of a capital raising transaction subsequent to the 2023 Rights Offering in an amount equal to the lesser of (A) the net proceeds of such capital raise or (B) the full amount outstanding of the Duggan September Note. Following the issuance of the two new Promissory Notes (the “Duggan Promissory Notes”), the Duggan February Note and Duggan September Note were marked as “cancelled” on their faces and replaced in their entirety by the Duggan Promissory Notes (together with the Zanganeh Note, the “Notes”). The Notes accrue interest at an initial rate of 7.5%. All interest on the Notes were paid on the date of signing for the period through February 15, 2023. Such prepaid interest was paid in a number of shares of the Company’s common stock, par value $0.01 equal to the dollar amount of such prepaid interest, divided by $0.7913 (the consolidated closing bid price immediately preceding the time the Company entered into the Note Purchase Agreement, plus $0.01), which was 9,346,434 shares to Mr. Duggan and 373,857 shares to Dr. Zanganeh. For all applicable periods following February 15, 2023, interest shall accrue on the outstanding principal balance of the Notes at the US prime interest rate, as reported in the Wall Street Journal, plus 50 basis points, as adjusted monthly, for three months immediately following February 15, 2023, and thereafter at the US prime rate plus 300 basis points, as adjusted monthly. In connection with the closing of the 2023 Rights Offering, the $400 million Duggan February Note matured and became due, and the Company repaid all principal and accrued interest thereunder using a portion of the proceeds from the 2023 Rights Offering. During the year ended December 31, 2023, the Company made payments for interest of $10.7 million.

On March 10, 2022, the Company entered into a note purchase agreement with Mr. Duggan, pursuant to which Mr. Duggan loaned the Company $25.0 million in exchange for the issuance by the Company of an unsecured promissory note in the amount of $25.0 million (the “2022 Note”). The 2022 Note accrued interest at a rate per annum equal to the prime rate as reported in the Wall Street Journal, which was 3.25% as of the effective date. The 2022 Note became due upon the earlier of (i) the consummation of a registered public offering with net proceeds of no less than $25.0 million or (ii) 18 months from the date of issuance of the 2022 Note, and was repaid on August 10, 2022.

On August 16, 2022, 94,849,203 shares were purchased by Mr. Duggan in connection with the July 2022 rights offering (“2022 Rights Offering”).

Transactions with Dr. Mahkam Zanganeh

In December 2023, Dr. Zanganeh exercised warrants to purchase 805,495 shares. Refer to Note 20 in our consolidated financial statements contained in this Annual Report on Form 10-K for the warrants exercise activity for the year ended December 31, 2023.

As described above, on December 6, 2022, the Company entered into the Note Purchase Agreement with Mr. Duggan and Dr. Zanganeh, pursuant to which the Company agreed to sell to Mr. Duggan and Dr. Zanganeh the Notes in the aggregate amount of $520 million. Pursuant to the Note Purchase Agreement, the Company issued Dr. Zanganeh the Zanganeh Note in the amount of $20 million, which matured and became due on February 15, 2023. All interest on the Notes shall be paid on the date of signing for the period through February 15, 2023. Such prepaid interest was paid in a number of shares of the Company’s common stock equal to the dollar amount of such prepaid interest, which was 373,857 shares to Dr. Zanganeh. On February 15, 2023, the $20 million Zanganeh Note matured and the Company repaid the outstanding principal balance.

On August 16, 2022, (i) 184,430 shares were purchased by Dr. Zanganeh (ii) 4,593,777 shares were purchased by the Mahkam Zanganeh Revocable Trust, of which Dr. Zanganeh is a trustee, and (iii) 1,030,925 shares were purchased by the Shaun Zanganeh Irrevocable Trust, of which Dr. Zanganeh is a trustee in connection with the 2022 Rights Offering.

On May 12, 2021, 389,977 shares were purchased by the Mahkam Zanganeh Revocable Trust in connection with the 2021 Rights Offering.

On March 26, 2021, the Company entered into the Sublease with Dr. Zanganeh and Associates, Inc. (“MZA”) consisting of 4,500 square feet of space at 2882 Sand Hill Road, Menlo Park, CA (the “Sublease”). The Sublease runs until

September 2022. The rent payable under the terms of the Sublease is equivalent to the proportionate share of the rent payable by MZA to the third party landlord, based on the square footage of office space sublet by the Company, and no mark-up has been applied. During the year ended December 31, 2021, payments of $556 thousand were made pursuant to the sublease. During the year ended December 31, 2022, payments of $537 thousand were made pursuant to the sublease.

On July 25, 2022, the Company entered into the First Amendment, dated July 19, 2022 to the Sublease with MZA. The existing Sublease term, which was set to expire on September 30, 2022, was extended for a period of thirty-nine months from October 1, 2022 through December 31, 2025. The rent payable under the terms of the Sublease is equivalent to the proportionate share of the net payable by MZA to the third-party landlord, based on the square footage of office space sublet by the Company, and no mark-up has been applied. During the year ended December 31, 2023, payments of $0.8 million, were made pursuant to the first amendment to the Sublease Agreement.

On July 29, 2022, the Company entered into the Second Amendment, dated August 1, 2022, to the Sublease with MZA. The Second Amendment was effective as of August 1, 2022 and expires on December 31, 2025. The Second Amendment includes an additional 1,277 square feet (the “Expansion Premises”) of office space at 2882 Sand Hill Road, Menlo Park, California. The rent payable under the terms of the Sublease is equivalent to the proportionate share of the net payable by MZA to the third-party landlord, based on the square footage of office space sublet by the Company, and no mark-up has been applied. During the year ended December 31, 2023 payments of $218 thousand, were made pursuant to the Secondment Amendment to the Sublease.

Transactions with Dr. Yu (Michelle) Xia

On December 5, 2022, the Company entered into a Collaboration and License Agreement (the “License Agreement”) with Akeso, Inc. and its affiliates (“Akeso”) and certain ancillary transaction documents as set forth in the License Agreement. The License Agreement closed on January 17, 2023 following customary waiting periods, and both Akeso and Summit entered into the Common Stock Issuance Agreement (“Issuance Agreement”). Pursuant to the License Agreement and Issuance Agreement, Akeso elected to receive 10 million shares of Company common stock in lieu of cash and was paid $274.9 million in cash as the initial upfront payment. The $200 million remaining amount of the $500 million upfront payment was paid on March 5, 2023. The Company and Akeso also entered into Amendment No. 1 to the License Agreement, dated January 16, 2023 (the “License Agreement Amendment”), to modify the Akeso party receiving payments under the License Agreement from Akeso Biopharma Co., Ltd. to Akeso, Inc. Upon the closing of the License Agreement, the Board of Directors of the Company appointed Dr. Yu (Michelle) Xia, current Chief Executive Officer and Chairwoman of Akeso, to serve as a member of the Board of Directors pursuant to the terms of the License Agreement.

The Company paid approximately $2.5 million to Akeso during year ended December 31, 2023. As of December 31, 2023, the Company included in accrued expenses approximately $3.6 million due to Akeso.

Transactions with Mr. Manmeet Soni

On October 16, 2023, the Company announced the appointment of Mr. Manmeet Soni as its Chief Operating Officer, effective immediately. Mr. Soni has been a part of the Company’s Board of Directors since 2019. He will remain a member of the Board of Directors. In conjunction with his appointment, Mr. Soni entered into a share purchase agreement with the Company to purchase $5.0 million of its common stock via a private placement. The transaction was effective October 13, 2023 with a closing price of $1.68, resulting in the purchase of 2,976,190 shares of the Company’s common stock.

Indemnification Agreements

Our certificate of incorporation provides that we will indemnify our directors and officers to the fullest extent permitted by Delaware law. In addition, we have entered into indemnification agreements with all of our directors and named executive officers. These indemnification agreements may require us, among other things, to indemnify each such director or executive officer for some expenses, including attorneys’ fees, judgments, fines, and settlement amounts incurred by him or her in any action or proceeding arising out of his or her service as one of our directors or executive officers.

Employment Arrangements

We have entered into employment agreements with certain of our executive officers. For more information regarding the agreements with our named executive officers, see “Executive Compensation.”

Item 14. Principal Accounting Fees and Services

Auditor Services and Fees

Policy on Audit Committee’s Pre-Approval of Audit and Permissible Non-Audit Services of Independent Registered Public Accounting Firm

The Audit Committee reviews and pre-approves all audit and permissible non-audit services provided by the independent registered public accounting firm. These services may include audit services, audit-related services and tax services, as well as specifically designated non-audit services which, in the opinion of the Audit Committee, will not impair the independence of the independent registered public accounting firm. Pre-approval generally is provided for up to one year, and any pre-approval is detailed as to the particular service or category of services and generally is subject to a specific budget. The independent registered public accounting firm and the Company’s management are required to periodically report to the Audit Committee regarding the extent of services provided by the independent registered public accounting firm in accordance with this pre-approval, including the fees for the services performed to date. In addition, the Audit Committee also may pre-approve particular services on a case-by-case basis, as necessary or appropriate.

Auditor Fees

The following table sets forth the approximate aggregate fees billed to the Company by PricewaterhouseCoopers LLP for the years ending December 31, 2023 and 2022, respectively (in thousands):

Fee Category Year Ended December 31, 2023 Year Ended December 31, 2022

Audit-Related Fees — —

Tax Fees — —

All Other Fees 4 4

Audit Fees: Audit fees for both years consisted of professional services rendered for: (i) the audit of our annual consolidated financial statements, (ii) statutory audits, (iii) the review of our consolidated financial statements included in our quarterly reports on Form 10-Q and (iv) audit services associated with other reports filed with the Securities and Exchange Commission.

Audit-Related Fees: Consists of fees for professional services that are reasonably related to the performance of the audit or review of the Corporation’s financial statements and which are not reported under “Audit Fees” above. There were no audit-related fees for the year ended December 31, 2023 and 2022, respectively.

Tax Fees: Consists of fees for professional services for tax compliance, tax advice and tax planning. There were no tax fees for the year ended December 31, 2023 and 2022, respectively.

All Other Fees: All other fees for the year ended December 31, 2023 and 2022, respectively, related to a subscription to a global research and disclosure software platform.

The Audit Committee has concluded that the provision of the non-audit services listed above was compatible with maintaining the independence of PricewaterhouseCoopers LLP.

PART IV

Item 15. Exhibits, Financial Statement Schedules

(1) Financial Statements

As part of this Report, the consolidated financial statements are listed in the accompanying index to financial statements on page 106.

(2) Financial Statement Schedules

All financial statement schedules have been omitted because they are not applicable, not required, or the information required is shown in the consolidated financial statements or the notes thereto.

(3) Exhibits

The exhibits filed as part of this Report are listed below.

Exhibit No. Description

100

Exhibit No. Description

10.45# Amended and Restated 2020 Stock Incentive Plan, dated July 27, 2022

21.1* List of Significant Subsidiaries

101

Exhibit No. Description

97.1* Summit Therapeutics, Inc. Incentive-based Compensation Clawback Policy

101.SCH* Inline XBRL Taxonomy Extension Schema Document

101.CAL* Inline XBRL Taxonomy Extension Calculation Linkbase Document

101.DEF* Inline XBRL Taxonomy Extension Definition Linkbase Document

101.LAB* Inline XBRL Taxonomy Extension Label Linkbase Document

101.PRE* Inline XBRL Taxonomy Extension Presentation Linkbase Document

* Filed herewith.

# Indicates management contract or compensatory plan or arrangement.

Item 16. Report Summary

None.

102

SIGNATURES

SMMT US Equity

SMMT · 10-K · period ended 2023-12-31

Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations

Item 7A. Quantitative and Qualitative Disclosures About Market Risk

Item 8. Financial Statements and Supplementary Data

Item 9. Changes in and Disagreements with Accountants on Accounting and Financial Disclosure

Item 9A. Controls and Procedures

Item 9B. Other Information

Item 9C. Disclosure Regarding Foreign Jurisdictions that Prevent Inspections

Item 10. Directors, Executive Officers and Corporate Governance

Item 11. Executive Compensation

Item 12. Security Ownership of Certain Beneficial Owners and Management and Related Stockholder Matters

Item 13. Certain Relationships and Related Party Transactions

Item 14. Principal Accounting Fees and Services

Item 15. Exhibits, Financial Statement Schedules

Item 16. Report Summary

SMMT US Equity☆

SMMT · 10-K · period ended 2023-12-31

Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations

Item 7A. Quantitative and Qualitative Disclosures About Market Risk

Item 8. Financial Statements and Supplementary Data

Item 9. Changes in and Disagreements with Accountants on Accounting and Financial Disclosure

Item 9A. Controls and Procedures

Item 9B. Other Information

Item 9C. Disclosure Regarding Foreign Jurisdictions that Prevent Inspections

Item 10. Directors, Executive Officers and Corporate Governance

Item 11. Executive Compensation

Item 12. Security Ownership of Certain Beneficial Owners and Management and Related Stockholder Matters

Item 13. Certain Relationships and Related Party Transactions

Item 14. Principal Accounting Fees and Services

Item 15. Exhibits, Financial Statement Schedules

Item 16. Report Summary

SMMT US Equity