UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 6-K

REPORT OF FOREIGN PRIVATE ISSUER

PURSUANT TO RULE 13a-16 OR 15d-16

OF THE SECURITIES EXCHANGE ACT OF 1934

For the month of May 2024

(Commission File No. 001-38215)

NUCANA PLC

(Translation of registrant’s name into English)

3 Lochside Way

Edinburgh EH12 9DT

United Kingdom

(Address of registrant’s principal executive office)

Indicate by check mark whether the registrant files or will file annual reports under cover Form 20-F or Form 40-F.

Form 20-F ☒    Form  40-F ☐

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101 (b) (1): ☐

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101 (b) (7): ☐

Other Events

On May 13, 2024, NuCana plc (the “Company”) published its 2023 UK Annual Report (the “UK Annual Report”) for the year ended December 31, 2023 and distributed a notice of its annual general meeting to be held on June 18, 2024 (the “AGM”), a form of proxy and its UK Annual Report to its ordinary shareholders. The notice of the AGM is attached as Exhibit 99.1 hereto and the UK Annual Report is attached as Exhibit 99.2 hereto.

On or about May 13, 2024, Citibank, N.A., in its capacity as the depositary bank (the “Depositary”) for the Company’s American Depositary Shares (“ADSs”), commenced mailing notice materials and voting cards to ADS holders to enable ADS holders of record as of May 6, 2024 to instruct the Depositary to vote the ordinary shares represented by their ADSs. If the Depositary receives timely voting instructions from an ADS holder, it will endeavor to vote the ordinary shares (in person or by proxy) represented by the holder’s ADSs in accordance with the ADS holder’s voting instructions. The ability of the Depositary to carry out voting instructions may be limited by practical and legal limitations and ADS holders may not receive voting materials in time to enable them to return voting instructions to the Depositary in a timely manner. The notice materials to be mailed by the Depositary to ADS holders will contain a link to the Company’s website where ADS holders can view and download the AGM notice distributed by the Company to its ordinary shareholders (which contains explanatory notes for the resolutions being voted on at the AGM) and the UK Annual Report.

The information contained in Exhibits 99.1 and 99.2 shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or incorporated by reference in any filing under the Securities Act of 1933, as amended, or the Exchange Act, unless expressly set forth by specific reference in such a filing.

Exhibits

SIGNATURES

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

Date: May 13, 2024

Exhibit 99.1

Notice f 2024 Annual General Meeting Tuesday, 18th June 2024 at 11.00am Venue: Lochside House 3 Lochside Way Edinburgh EH12 9DT U.K.

NuCana plc

77-78 Cannon Street, London, England, EC4N 6AF

Company number: 03308778

NOTICE OF 2024 ANNUAL GENERAL MEETING

NOTICE is hereby given that the 2024 annual general meeting of NuCana plc (the “Company”) will be held on 18 June 2024 at 11.00am at Lochside House, 3 Lochside Way, Edinburgh EH12 9DT, UK for transaction of the following business:

Ordinary Resolutions

To consider and, if thought fit, pass the following resolutions (1 to 7 inclusive), which will be proposed as ordinary resolutions:

Special Resolution

To consider and, if thought fit, pass the following resolution 8, which will be proposed as a special resolution:

Recommendation

The directors of the Company consider that all the proposals to be considered at the AGM are in the best interests of the Company and its shareholders as a whole and are most likely to promote the success of the Company. The directors unanimously recommend that you vote in favour of all the proposed resolutions as they intend to do in respect of their own beneficial holdings.

Martin Quinn

Company Secretary

10 May 2024

YOUR VOTE IS IMPORTANT. Members will be able to attend the AGM in person however you are strongly encouraged to vote on all resolutions in advance of the AGM by appointing the Chair of the meeting as your proxy. Further details on how shareholders can appoint the Chair of the meeting as their proxy are set out in this document.

NOTES

The following notes explain your general rights as a member and your right to attend and vote at the annual general meeting or to appoint someone else to vote on your behalf.

CREST members and, where applicable, their CREST sponsors or voting service providers should note that EUI does not make available special procedures for any particular messages. Normal system timings and limitations will therefore apply in relation to the input of CREST proxy instructions. It is the responsibility of the CREST member concerned to take (or, if the CREST member is a CREST personal member or sponsored member or has appointed a voting service provider, to procure that his CREST sponsor or voting service provider takes) such action as shall be necessary to ensure that a message is transmitted by any particular time. Reference should be made to those sections of the CREST Manual concerning practical limitations of the CREST system and timings.

The Company may treat as invalid a CREST proxy instruction in the circumstances set out in Regulation 35(5)(a) of the Uncertificated Securities Regulations 2001.

EXPLANATORY NOTES TO THE RESOLUTIONS PROPOSED AT THE ANNUAL GENERAL MEETING

The resolutions to be proposed at the AGM of the Company to be held on 18 June 2024 at 11.00am are set out in this Notice of AGM. The following notes provide an explanation to the resolutions being put to shareholders.

Ordinary Resolutions

Resolutions 1 to 7 are proposed as ordinary resolutions. Assuming that a quorum is present, an ordinary resolution is passed on a show of hands if it is approved by a simple majority (more than 50%) of the votes cast by shareholders present (in person or by proxy) at the meeting and entitled to vote. On a poll, an ordinary resolution is passed if it is approved by holders representing a simple majority of the total voting rights of shareholders present (in person or by proxy) who (being entitled to vote) vote on the resolution.

Resolution 1 - 2: Re-election of directors

Under the Company’s Articles of Association there are three classes of board members (Class I, Class II and Class III) with each class having a specified term of office. The Company’s Articles of Association require the Class III directors to retire from office this year. Adam George currently serves as a Class III director. Adam George is retiring and (being eligible) is standing for re-election as a Class III director at the AGM. Martin Mellish currently serves as a Class III director. Martin Mellish is retiring and (being eligible) is standing for re-election as a Class III director at the AGM. Biographical information for each director standing for re-election is included on page 9 of this Notice.

THE BOARD RECOMMENDS A VOTE FOR THE RE-ELECTION OF EACH OF ADAM GEORGE AND MARTIN MELLISH TO THE BOARD OF DIRECTORS.

Resolution 3: Re-appointment of auditors

The Act requires that auditors be appointed at each general meeting, at which accounts are laid, to hold office until the next AGM. The appointment of Ernst & Young LLP as auditors of the Company terminates at the conclusion of the AGM. They have indicated their willingness to stand for reappointment as auditors of the Company until the conclusion of the AGM in 2025.

The Audit Committee has assessed the effectiveness, independence and objectivity of the auditors, Ernst & Young LLP, and concluded that the auditors were in all respects effective.

THE BOARD RECOMMENDS A VOTE FOR THE RE-APPOINTMENT OF ERNST & YOUNG LLP AS AUDITORS.

Resolution 4: Authorising and fixing the remuneration of the auditors

This resolution gives authority to the directors to determine the auditors’ remuneration.

It is normal practice for shareholders to resolve at the AGM that the directors shall decide on the level of remuneration of the auditors for the audit work to be carried out by them in the next financial year. The amount of the remuneration paid to the auditors for the next financial year will be disclosed in the next audited accounts of the Company.

THE BOARD RECOMMENDS A VOTE FOR THE AUTHORISATION OF THE DIRECTORS TO DETERMINE THE AUDITORS’ REMUNERATION.

Resolution 5: Laying of accounts

The directors are required to present to shareholders at the AGM, the annual accounts of the Company for the year ended 31 December 2023, the Strategic Report, the Directors’ Report and the Auditors’ Report on the accounts.

THE BOARD RECOMMENDS A VOTE FOR THE RESOLUTION TO RECEIVE THE ANNUAL ACCOUNTS OF THE COMPANY FOR THE YEAR ENDED 31 DECEMBER 2023, THE STRATEGIC REPORT, THE DIRECTORS’ REPORT AND THE AUDITORS’ REPORT ON THE ACCOUNTS.

Resolution 6: Directors’ Remuneration Report

Shareholders are invited to cast their vote on the Directors’ Remuneration Report, in accordance with Section 439 of the Act. The Directors’ Remuneration Report is set out on pages 17 to 26 of the Company’s annual accounts and reports for the year ended 31 December 2023. The vote is advisory in nature and therefore no entitlement to remuneration is conditional on the passing of this resolution.

THE BOARD RECOMMENDS A VOTE FOR THE RESOLUTION TO RECEIVE AND APPROVE THE DIRECTORS’ REMUNERATION REPORT FOR THE FINANCIAL YEAR ENDED 31 DECEMBER 2023.

Background to Resolution 7 and Special Resolution 8

As a matter of U.K. company law, directors of a company incorporated in England must have authority from shareholders to allot or grant rights to subscribe for, or to convert any security into, the company’s shares. In addition, when an allotment of shares is for cash, the company must first offer those shares on the same terms to existing shareholders of the company on a pro-rata basis (commonly referred to as statutory pre-emption rights) unless these statutory pre-emption rights are dis-applied, by approval of the shareholders.

Resolutions 7 and 8, which we refer to as our “Share Issuance Proposals,” ask our shareholders for authority for the directors to allot shares or grant rights over shares up to an aggregate nominal amount of £20,000,000 and the power for the directors to allot shares or grant rights over shares for cash up to an aggregate nominal amount of £20,000,000 on a non-preemptive basis. This authority and power would expire at the conclusion of our 2025 AGM.

Many of our peer companies are listed and incorporated in the United States, and are thus not subject to similar share issuance restrictions. We are asking you to approve our Share Issuance Proposals to allow us to continue to execute on our business and growth strategy in a timely and competitive manner.

Should our shareholders not approve resolutions 7 and 8, whilst we appreciate that we would still have the ability to seek shareholder approval in connection with a specific issuance of shares on a case-by-case basis by convening general meetings from time to time, we do not believe that such an approach is a workable alternative to obtaining approval of resolutions 7 and 8 at the AGM as we propose. The uncertainty as to whether we could obtain shareholder approval for a specific issuance, as well as the delays we would experience in seeking and obtaining such approval, could be harmful to the terms of such a share issuance. In addition, the case-by-case approval approach ignores market windows and other deal timing and competitive realities.

Specifically, the requirement to first offer shares, that we propose to issue for cash, to all of our existing shareholders in time-consuming pro-rata rights offerings would considerably reduce the speed at which we could complete capital-raising activities undertaken in furtherance of our growth strategy, would increase our costs, might otherwise make it difficult or impossible for us to complete such transactions, and could put us at a distinct competitive disadvantage relative to our peer companies.

Access to capital and the ability to raise equity capital at short notice have been important factors that have contributed to our ability to execute our long-term growth strategy. In practice, offering shares to existing shareholders in accordance with U.K. statutory pre-emption rights can be time-consuming, so U.K. market practice for listed companies is to annually seek a shareholder resolution waiving or dis-applying pre-emption rights over new share issuances for cash, up to an agreed limit. We fully appreciate that our proposals are in excess of the investment advisory guidance in this regard and for this reason, our proposals may attract a negative voting recommendation from certain proxy advisory firms. However, we have an established track record since our IPO in October 2017 of securing annual shareholder support for a resolution dis-applying pre-emption rights over amounts of share capital in excess of the investment advisory guidance. Using these authorities, we have responsibly raised capital in order to execute our business plan.

We believe the request for authorisation and disapplication of pre-emption rights sought will provide us with the continued flexibility to raise equity capital that we believe we may require at this stage of development of the Company. This recognises the fact that as a development-stage business, we have needed access to equity capital to ensure that we can maintain the business appropriately capitalised to expedite our development programs. We have publicly stated that we believe our existing cash resources will be sufficient to fund the Company into 2025. We believe it is in the interests of all shareholders to ensure that we retain the ability to raise equity capital on reasonably short notice if advisable. We propose to seek an authority (to expire at the 2025 AGM) to allot shares or grant rights over shares and under this authority to seek the power to allot shares or grant rights over shares for cash on a non-preemptive basis over a maximum of 500,000,000 ordinary shares.

Where passed, in addition to these resolutions giving the Company the necessary flexibility to raise equity capital, they will also give authority to allot shares or grant rights to subscribe for shares under or in connection with any existing, amended or new share option schemes or long term incentive plans as the directors may approve without offering them first to existing shareholders in proportion to their current holdings. Importantly, this will allow the Company to maintain share option schemes with sufficient share reserves to appropriately compensate, motivate and retain our employees, directors and consultants, thereby aligning their interests with those of our shareholders.

Many of the companies with which we compete for talent are listed and incorporated in the United States and are not subject to similar restrictions on the authorisation of shares and disapplication of pre-emption rights related to shares. In this respect we believe the approval of Resolutions 7 and 8 is critical to enable us to continue to execute on our business strategy by attracting and retaining qualified employees, directors and consultants in a highly competitive market for talent.

The Share Issuance Proposals are consistent with U.S. capital markets practice and U.S. governance standards, and, if approved, will keep us on an equal footing with our peer companies which are incorporated and listed in the United States. We believe that the Share Issuance Proposals are appropriate to the needs of the Company and in the best interests of shareholders. We are therefore asking you to approve the Share Issuance Proposals to allow us to continue to execute our business and growth strategy in a timely and competitive manner.

Summary

The Share Issuance Proposals, if approved, will allow our Board of Directors continued flexibility to issue shares subject to other requirements of Nasdaq Stock Market and the Securities and Exchange Commission. The Share Issuance Proposals, as proposed:

Resolution 7: Authority to allot, or grant rights to subscribe for, shares

The directors may only allot shares or grant rights over shares if authorised to do so by shareholders.

Under this resolution the Board is seeking the authority to allot shares in the Company or grant rights to subscribe for or to convert any security into shares in the Company up to an aggregate nominal amount of £20,000,000 such authority, unless previously revoked or varied by the Company, to expire at the conclusion of the AGM of the Company to be held in 2025.

THE BOARD RECOMMENDS YOU VOTE FOR THE RESOLUTION SO AUTHORISING THE DIRECTORS.

Special Resolution

Resolution 8 is proposed as a special resolution. A special resolution requires the affirmative vote of not less than 75% of the votes cast by shareholders present (in person or by proxy) at the meeting and entitled to vote. On a poll, a special resolution is passed if it is approved by holders representing at least 75% of the votes cast (in person or by proxy) at the meeting who (being entitled to vote) vote on the resolution.

Resolution 8: Disapplication of pre-emption rights

Please consider our section above entitled Background to Resolution 7 and Special Resolution 8.

As a U.K. company, the Company’s shareholders are entitled, under Section 561 of the Act to pre-emption rights, whereby, in the event that the Company wishes to allot and issue new shares for cash or issue shares pursuant to any rights to subscribe for shares (whether pursuant to share option rights granted to employees or otherwise) those securities must first be offered to existing shareholders in proportion to the number of ordinary shares they each hold before they can be offered to new shareholders.

As set out above, in certain circumstances, it may be in the best interests of the Company to allot shares (or to grant rights over shares) for cash without first offering them proportionately to existing shareholders. This cannot be done under the Act unless the shareholders have first waived their pre-emption rights.

Therefore this resolution, which will be proposed as a special resolution subject to the passing of resolution 7, seeks the empowerment of the directors to allot equity securities under the authority given to them by resolution 7 above without offering them first to existing shareholders in proportion to their current holdings up to an aggregate nominal amount of £20,000,000.

THE BOARD RECOMMENDS YOU VOTE FOR THE RESOLUTION SO EMPOWERING THE DIRECTORS.

Appendix A: Directors’ Biography

Adam George (Director, appointed 2018)

Adam George has served as a member of our board of directors since April 2018. Mr. George served as GW Pharmaceutical’s U.K. Managing Director and Company Secretary from March 2017 to December 2020, Chief Financial Officer from 2012 to March 2017, and Financial Controller from 2007 to 2012. GW Pharmaceuticals is a biopharmaceutical company focused on discovering, developing and commercializing novel therapeutics from its proprietary cannabinoid product platform in a broad range of disease areas. In addition, Mr. George has served as chairman of the board of directors and chief executive officer of Psi Pharmaceuticals Ltd since December 2021 and as a member of the board of directors of Beckley Psytech Ltd since June 2021. Further, Mr. George also serves as a director of PsiClone Ltd, Neurone Ltd, and Kanna Health Ltd, private pharmaceutical development companies. Before joining GW Pharmaceuticals, Mr. George held several senior finance roles within both public and private companies. Mr. George holds a BSc. in Biology from Bristol University and is a Chartered Accountant. He also serves as Chairman of NuCana’s Audit Committee.

Based on his significant experience in the biopharmaceutical industry in positions including chief executive officer, chief operating officer and executive director the Corporate Nominating and Governance Committee concluded that Mr. George is qualified to serve on our Board of Directors.

THE BOARD RECOMMENDS A VOTE FOR THE RE-ELECTION OF ADAM GEORGE TO THE BOARD OF DIRECTORS.

Martin Mellish (Director, appointed 2009)

Martin Mellish has served as a member of our board of directors since December 2009. Mr. Mellish also serves as a non-executive director and Chairman of the Audit Committee of: Spectral AI (NASDAQ: MDAI; formerly London AIM: SMD) a company developing a medical Artificial Intelligence technology for the evaluation of acute burn and chronic diabetic wounds; and of Levitronix Technologies Inc., a technology company, handling high-purity fluids for the semiconductor and life science industries. Further, Mr. Mellish also serves as a director of Kensington Green Management Ltd., Alturki Holding, and Saudi Readymix Concrete Company. Mr. Mellish serves as founding director and Chairman of Aspen Advisory Services Ltd., a London-based private office responsible for the administration of investments in North America, Europe and Asia since 1994. Mr. Mellish holds an M.Sc. from the Master of Health Care Delivery Science program at Dartmouth’s Geisel School of Medicine and Tuck School of Business; an SM (Management) from the Massachusetts Institute of Technology and an M.Sc. (Accounting) from Northeastern University. He also serves as a member of NuCana’s Audit Committee.

Based on his significant experience in accounting, finance and in the life sciences sector, the Corporate Nominating and Governance Committee concluded that Mr. Mellish is qualified to serve on our Board of Directors.

THE BOARD RECOMMENDS A VOTE FOR THE RE-ELECTION OF MARTIN MELLISH TO THE BOARD OF DIRECTORS.

Lochside House,

3 Lochside Way,

Edinburgh,

EH12 9DT,

U.K.

T: +44 (0)131 357 1111

E: info@nucana.com

www.nucana.com

Exhibit 99.2

Annual Report 2023 for the year ended 31 December 2023

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introduction

NuCana was incorporated under the laws of England and Wales on 28 January 1997 under the name Biomed (UK) Limited and commenced operations in 2008. On 28 April 2008, we changed our name to NuCana BioMed Limited. On 29 August 2017, we re-registered as a public limited company and changed our name to NuCana plc. On 2 October 2017, we completed our initial public offering of American Depositary Shares, or ADSs, on the Nasdaq Global Select Market. On 9 November 2023 we transferred our listing to The Nasdaq Capital Market. Our ADSs are traded under the symbol “NCNA”. NuCana plc on behalf of itself and its subsidiaries, NuCana, Inc., NuCana Limited (incorporated in Ireland) and NuCana Biomed Trustee Company Limited (which may be referred to as “the Group”, “the Company”, “we”, “us” or “our”), is required to produce a strategic report complying with the requirements of the Companies Act 2006.

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our strategy

“Our goal is to transform standards of care and improve survival for patients across a wide range of cancer indications.”

Our strategy includes the following key components:

We reported additional data from our Phase lb/2 study, known as the NuTide:302 study, in patients with advanced colorectal cancer in October 2023 at the AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics 2023. In this study, NUC-3373 is being assessed for safety and a recommended Phase 2 dose when combined with many of the agents typically combined with 5-FU, including leucovorin, irinotecan, oxaliplatin and bevacizumab.

We are also conducting a randomised Phase 2 clinical study of NUC-3373, known as the NuTide:323 study, in combination with leucovorin, irinotecan and bevacizumab (NUFIRI + bev) versus the standard of care FOLFIRI + bev (5-FU, leucovorin, irinotecan and bevacizumab) in patients with second-line advanced colorectal cancer. In October 2023 we reported initial pooled safety data from the NuTide:323 study at the AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics 2023. On 20 March 2024, we announced that this 171-patient study was fully enrolled.

We plan to report additional data from both our Phase lb/2 study, NuTide:302, and our randomised Phase 2 study, NuTide:323, in 2024.

In order to capitalise on the widespread usage of 5-FU and the significant global commercial opportunity for a more effective and safer fluoropyrimidine, we have initiated a Phase 1b/2 modular study, known as the NuTide:303 study, of NUC-3373 in combination with the PD-1 inhibitor pembrolizumab for patients with advanced solid tumours and in combination with docetaxel for patients with lung cancer.

We plan to report data from our Phase 1b/2 study, NuTide:303, in 2024.

We completed enrolment in the Phase 1 dose-finding part of the ongoing Phase 1/2 study, known as the NuTide:701 study, of NUC-7738 in patients with advanced solid tumours. NUC-7738 is currently in the Phase 2 part of the NuTide:701 study, which is evaluating NUC-7738 as a monotherapy and in combination with the PD-1 inhibitor pembrolizumab for patients with advanced solid tumours. In October 2023, we presented interim data from the Phase 2 part of the NuTide:701 study at the AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics 2023.

We plan to report additional data from our Phase 1b/2 study, NuTide:701, in 2024.

We are pursuing the transformation of both well-established and widely used nucleoside analogues as well as novel nucleoside analogues, which we believe have the potential to address additional areas of unmet medical need in oncology.

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We own or have exclusive rights to the core technologies underlying our ProTide technology platform. We have been granted patents in key markets, including the United States, Europe and Japan, protecting the composition of matter of NUC-3373, NUC-7738, Acelarin and other product candidates. We intend to further expand and enhance our intellectual property position. We are actively evaluating new intellectual property opportunities as they arise, with the intention of further expanding our intellectual property position and defending our patents when necessary.

We have worldwide rights to all product candidates that we are developing. We believe that healthcare professionals who treat the majority of patients with the cancers we are initially targeting with our ProTides can be addressed by a focused sales and marketing team. We currently plan to commercialise any product candidates for which we receive regulatory marketing approval using a specialised sales force, either independently or in partnership with a commercialisation partner, in the United States and Europe.

our pipeline

We take a scientifically driven approach to designing ProTides, which we believe have the potential to result in highly efficacious cancer therapies with improved tolerability. Our pipeline of product candidates in clinical development and their current development stage is summarised below.

NuCana is currently developing a portfolio of new medicines to address a broad range of cancers, but we do not have any approved products. As further described in “Our Strategy”, our current intention is to build a sales and marketing capability in the United States and Europe to commercialise our ProTides. We may also consider partnerships, co-promotion agreements or other commercial arrangements, in certain geographic areas or otherwise, to most effectively address our market opportunities.

review of the business

Since our inception, we have incurred significant net losses and negative cash flows from operations. To date, we have financed our operations primarily through placements of equity securities, an initial public offering, a follow-on public offering and research and development tax credits.

DEVELOPMENT AND PERFORMANCE DURING THE PERIOD

Research and Development Expenses

Research and development expenses were £25.1 million for the year ended 31 December 2023 as compared to £36.4 million for the year ended 31 December 2022, a decrease of £11.3 million. Clinical study expenses decreased by £3.2 million in 2023 compared with 2022 largely

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due to the discontinuation of the Phase 3 clinical study of Acelarin in March 2022, partially offset by increased expenditure on NuTide:323. Manufacturing costs decreased by £1.9 million in 2023 compared with 2022 primarily due to phasing of NUC-3373 manufacturing activity. Patent costs decreased by £5.0 million in 2023 compared with 2022 primarily due to 2022 including the recognition of total provisions of £4.1 million, as well as there was less patent defense activity in 2023. Other research and development costs decreased in 2023 by £1.2 million principally due to lower personnel costs and share-based payment expenses.

The following table gives a breakdown of the research and development costs incurred by product for the years ended 31 December 2023 and 2022:

Administrative Expenses

Administrative expenses were £6.1 million for the year ended 31 December 2023 as compared to £7.3 million for the year ended 31 December 2022, a decrease of £1.2 million. The decrease was primarily related to lower share-based payment expenses, professional fees and insurance costs.

Impairment of Intangible Assets

We regularly review our patent portfolio and during 2023 further development associated with a limited number of non-core patents or patent applications, relating mainly to preclinical drug candidates, was discontinued. Management concluded that this was an indication of impairment and an impairment charge of £0.5 million has been recognised, representing the full aggregate carrying value of those patents as of 31 December 2023. This compared to an impairment charge of £0.3 million recognised during the year ended 31 December 2022.

Net Foreign Exchange (Losses) Gains

For the year ended 31 December 2023, we reported a net foreign exchange loss of £1.2 million as compared to a net foreign exchange gain of £4.9 million for the year ended 31 December 2022. In 2023, the loss primarily arose from cash balances held in U.S. dollars and the U.S. dollar depreciating relative to the U.K. pound sterling. Conversely in 2022, the gain arose from cash balances held in U.S dollars and the U.S. dollar appreciating relative to the U.K. pound sterling.

Finance Income

Finance income represents bank interest and was £0.8 million for the year ended 31 December 2023 and £0.7 million for the year ended 31 December 2022. The increase in bank interest resulted from higher rates of interest being earned on cash deposits.

Income Tax Credit

The income tax credit, which is largely comprised of research and development tax credits, amounted to £4.4 million for the year ended 31 December 2023 and £6.4 million for the year ended 31 December 2022. The decrease in the income tax credit was primarily attributable to a decrease in our eligible research and development expenses, a decrease in the tax credit rate and an adjustment relating to prior periods of £0.2 million.

POSITION OF GROUP AT YEAR END

Liquidity and Capital Resources

Overview

Since our inception, we have incurred significant operating losses and negative operating cash flows. We anticipate that we will continue to incur losses for at least the next several years. As a result, we will need additional capital to fund our operations, which we may obtain from additional equity financings, debt financings, research funding, collaborations, contract and grant revenue or other sources.

As of 31 December 2023 and 31 December 2022, we had cash and cash equivalents of £17.2 million and £41.9 million, respectively. We do not currently have any approved products and have never generated any revenue from product sales. To date we have financed our operations primarily through the issuances of our equity securities.

In August 2021, we entered into an “at-the-market” (ATM) sales agreement with Jefferies LLC, or Jefferies, pursuant to which we may sell from time to time, ADSs having an aggregate offering price of up to $100.0 million through Jefferies, acting as our agent. Sales of our ADSs pursuant to this ATM program are subject to certain conditions specified in the sales agreement. Sales under the ATM program are registered on a shelf registration statement on Form F-3 that we filed with the SEC in August 2021, and which permits the offering, issuance and sale by us of up to a maximum aggregate offering price of $400.0 million of our securities, inclusive of our ADSs sold under the ATM program. During the year ended 31 December 2023 we sold and issued 408,015 ADSs, representing 408,015 ordinary shares, under the ATM program, raising gross proceeds of £0.2 million. Subsequent to the year end a further £1.5 million gross proceeds were raised through this ATM program.

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Cash Flows

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

Operating activities

Net cash used in operating activities was £26.4 million in 2023 as compared to £23.2 million in 2022, a net increase in cash outflows of £3.2 million. Operating loss cash flows were lower by £3.3 million in 2023, primarily reflecting lower research and development costs, partially offset by movement in provisions. Working capital outflows were £1.3 million for the year ended 31 December 2023 as compared to working capital inflows of £3.7 million for the year ended 31 December 2022. In addition, a tax refund of £5.6 million was received in 2023 compared to £7.2 million in 2022.

Investing activities

Net cash from investing activities was £2.9 million in 2023 as compared to £0.1 million in 2022. Repayment of other assets totalled £2.6 million in the year ended 31 December 2023 with no similar repayment in 2022. Interest received in 2023 was £0.8 million compared with £0.6 million in 2022, an increase of £0.2 million.

Financing activities

Net cash used in financing activities was £0.1 million in 2023 as compared to £0.2 million in 2022 reflecting a decrease in the proceeds from the issue of share capital.

main business trends and factors

NUC-3373 is currently being evaluated in three ongoing clinical studies: a Phase 1b/2 study (NuTide:302) in combination with leucovorin, irinotecan or oxaliplatin, and bevacizumab in patients with metastatic colorectal cancer; a randomised Phase 2 study (NuTide:323) in combination with leucovorin, irinotecan, and bevacizumab for the second-line treatment of patients with advanced colorectal cancer; and a Phase 1b/2 modular study (NuTide:303) of NUC-3373 in combination with the PD-1 inhibitor pembrolizumab for patients with advanced solid tumours and in combination with docetaxel for patients with lung cancer. NUC-7738 is in the Phase 2 part of a Phase 1/2 study in patients with advanced solid tumours which is evaluating NUC-7738 as a monotherapy and in combination with pembrolizumab. We have retained worldwide rights to these lead product candidates as well as our preclinical product candidates, all of which we refer to as ProTides. The key business trends affecting our development and performance during and at the period ended 31 December 2023 are detailed above.

In addition to these internal trends that have impacted our financial results, we may also in the future face competition for our products if they are approved. The most common methods of treating patients with cancer are surgery, radiation and drug therapy, including chemotherapy, hormone therapy, immunotherapy and targeted drug therapy. There are a variety of available drug therapies marketed for cancer, including many which are administered in combination to enhance efficacy. We believe that our product candidates, if approved, will principally face competition from other chemotherapies, immunotherapy and targeted drug therapies. In the field of chemotherapy, our competitors include companies that manufacture off-patent chemotherapies, including 5-FU, as well as companies that have developed new or improved chemotherapies. In addition, our product candidates, if approved, may face competition from cancer therapies developed by other companies using phosphoramidate chemistry, as well as other approved drugs or drugs that may be approved in the future for indications for which we may develop our product candidates.

The availability of reimbursement from government and other third-party payors will also significantly affect the pricing and competitiveness of our products. Our competitors also may obtain FDA or other regulatory approval for their products more rapidly than we may obtain approval for ours, which could result in our competitors establishing a strong market position before we are able to enter the market. Many of the companies against which we may compete have significantly greater financial resources and expertise in research and development, manufacturing, preclinical testing, conducting clinical studies, obtaining regulatory approvals and marketing approved products than we do.

Smaller or early-stage companies may also prove to be significant competitors, particularly through collaborative arrangements with large and established companies. These competitors also compete with us in recruiting and retaining qualified scientific and management personnel and establishing clinical study sites and patient registration for clinical studies, as well as in acquiring technologies complementary to, or necessary for, our programs.

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As a measurement of liquidity, we review our total liquidity position (including cash and cash equivalents), as well as our operating cash flow. At 31 December 2023, the total liquidity position was £17.2 million (at 31 December 2022: £41.9 million). Net cash used in operating activities was £26.4 million for the year ended 31 December 2023 (year ended 31 December 2022: £23.2 million).

principal risks and uncertainties

In common with other pharmaceutical development companies NuCana faces a number of risks and uncertainties. Internal controls are in place to help identify, manage and mitigate these risks. Further details of risk factors considered by NuCana for the year ended 31 December 2023 are included on Form 20-F filed with the SEC on 20 March 2024.

Financial

We have incurred significant operating losses since our inception. We incurred net losses of £27.6 million for the year ended 31 December 2023 and £32.0 million for the year ended 31 December 2022. As of 31 December 2023, we had an accumulated deficit of £207.7 million. Our product candidate, NUC-3373, is currently being evaluated in three ongoing clinical studies: a Phase 1b/2 study (NuTide:302) in combination with other agents, in patients with advanced colorectal cancer; a randomised Phase 2 clinical study of NUC-3373 (NuTide:323), in combination with approved anti-cancer agents including leucovorin, irinotecan, and bevacizumab for the second-line treatment of patients with advanced colorectal cancer; and a Phase 1b/2 clinical study (NuTide:303) in combination with the PD-1 inhibitor pembrolizumab for patients with advanced solid tumours and in combination with docetaxel for patients with lung cancer. Our product candidate NUC-7738 is currently in the Phase 2 part of a Phase 1/2 clinical study (NuTide:701) for patients with advanced solid tumours which is evaluating NUC-7738 as a monotherapy and in combination with pembrolizumab. It may be several years, if ever, before we have a product candidate ready for commercialisation. To date, we have financed our operations primarily through public and private placements of our equity securities. We expect to continue to incur significant expenses and operating losses for the foreseeable future. The net losses we incur may fluctuate significantly from quarter to quarter.

We anticipate that our expenses will increase substantially if and as we conduct larger-scale clinical studies of, and seek marketing approval for, our product candidates. In addition, if we obtain marketing approval for any of our product candidates, we expect to incur significant commercialisation expenses related to product sales, marketing, manufacturing and distribution. We may also need to raise additional funds sooner if we choose to pursue additional indications or geographies for our product candidates or otherwise expand more rapidly than we presently anticipate. Furthermore, we will continue to incur costs associated with operating as a public company. Accordingly, we will need to obtain substantial additional funding in connection with our continuing operations. If we fail to obtain additional financing, we may be unable to complete the development and commercialisation of our product candidates or continue our development programmes.

Dependence on Clinical Candidates

We do not currently generate any revenues from sales of any products, and we may never be able to develop or commercialise a marketable product. We have invested substantially all of our efforts and financial resources to date in the development of NUC-3373 and NUC-7738, as well as Acelarin, for which we discontinued the NuTide:121 clinical study in March 2022. Our ability to generate product revenues, which we do not expect will occur for at least the next several years, if ever, will depend heavily on the successful development and eventual commercialisation of these product candidates, if approved, which may never occur. Each of NUC-3373 and NUC-7738 will require additional clinical development, management of clinical, preclinical and manufacturing activities, regulatory approval in multiple jurisdictions, procurement of manufacturing supply, commercialisation, substantial additional investment and significant marketing efforts before we generate any revenues from product sales, if at all. We are not permitted to market or promote any product candidates in the United States, Europe or other countries before we receive regulatory approval from the FDA, the European Medicines Agency (EMA) or comparable foreign regulatory authorities, and we may never receive such regulatory approval for NUC-3373, NUC-7738 or any future product candidate. We have not submitted a New Drug Application, or NDA, to the FDA, a Marketing Authorisation Application, or MAA, to the EMA or comparable applications to other regulatory authorities for any of our product candidates and do not expect to be in a position to do so in the foreseeable future.

Going Concern

The development of pharmaceutical drugs is capital-intensive. We have incurred recurring losses from our operations, have an accumulated deficit totalling £207.7 million and cash flows used in operating activities of £26.4 million as of and for the year ended 31 December 2023. We had cash and cash equivalents of £17.2 million at 31 December 2023. We expect our expenses to increase in the medium to long-term with our ongoing activities, particularly if we conduct larger-scale clinical studies of, and seek marketing approval for, our product candidates.

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In addition, if we obtain marketing approval for any of our product candidates, we expect to incur significant commercialisation expenses related to product sales, marketing, manufacturing and distribution. Furthermore, we will continue to incur costs associated with operating as a public company. Accordingly, we will need to obtain substantial additional funding in connection with our continuing operations. In addition, we have based estimates of our cash runway on assumptions including, but not limited to, our expectations as to our future expenses and costs and our continued eligibility to receive and timing of R&D tax credits in the United Kingdom. There is no assurance that these assumptions will be correct and, as a result, we could use our available capital resources sooner than we currently expect. The timing of R&D tax credits is out with management’s control and any significant delay in receipt of these tax credits would result in the company exhausting its cash balances earlier than forecast within the going concern assessment period. Because of these funding needs and related risks and the current cash balance on hand, there is material uncertainty related to our ability to raise sufficient additional capital within the going concern period, prior to our cash balances being exhausted, which occurs in the going concern assessment period. These events or conditions give rise to a material uncertainty that may cast doubt on the Group and Company’s ability to continue as a going concern and, therefore, that it may be unable to realise its assets and discharge its liabilities in the normal course of business. If we are unable to obtain funding on a timely basis, we may be required to significantly curtail, delay or discontinue one or more of our research or development programs or the commercialisation of any product candidate or be unable to expand our operations or otherwise capitalise on our business opportunities, or cease trading. We may also need to raise additional funds if we choose to pursue additional indications or geographies for development and commercialisation of our product candidates or otherwise expand more rapidly than we presently anticipate.

In light of the foregoing, we have disclosed in the notes to our financial statements that there is material uncertainty related to the ability of us to raise sufficient additional capital within the going concern assessment period, prior to the cash balances being exhausted. The independent auditor’s report to the members of NuCana plc includes an explanatory paragraph stating that we have concluded that a material uncertainty exists about our ability to continue as a going concern. The inclusion of these may negatively impact the trading price of our securities, have an adverse impact on our relationship with third parties with whom we do business, including our customers, vendors and employees, and could make it challenging and difficult for us to raise additional equity or debt financing to the extent needed, all of which could have a material adverse impact on our business, results of operations, financial condition and prospects..

Economic and Political

As a company based in the United Kingdom, our business is subject to risks associated with conducting business internationally. Many of our suppliers and collaborative and clinical trial relationships are located outside of the United Kingdom and United States. Accordingly, our future results or our ability to raise additional capital could be harmed by a variety of factors, including:

Manufacturing

We do not currently own or operate, nor do we have any plans to establish in the future, any manufacturing facilities. We rely, and expect to continue to rely, on third parties for the manufacture and shipment of our product candidates for preclinical studies and clinical studies, as well as for the commercial manufacture of our drugs if any of our product candidates receive marketing approval. This reliance on third parties increases the risk that we will not have sufficient quantities of our product candidates or drugs or such quantities at an acceptable cost or quality, which could delay, prevent or impair our development or commercialisation efforts.

Commercialisation

We currently have no marketing capability or sales force, but we intend to commercialise or participate in the commercialisation of our product candidates for which we receive regulatory approval in major markets, such as the United States and Europe. This may necessitate building a specialised sales force and other commercial capabilities in such markets. To achieve commercial success for any approved product candidate for which we retain sales and marketing responsibilities, we must build our sales, marketing, managerial and other non-technical capabilities or make arrangements with third parties to perform these services. There are risks involved with both establishing our own sales and marketing capabilities and entering into arrangements with third parties to perform these services. For example, recruiting and training a sales force is expensive and time consuming and could delay any drug launch. If the commercial launch of a product candidate for which we recruit a sales force and establish marketing capabilities is delayed or does not occur for any reason, we would have prematurely or unnecessarily incurred these commercialisation expenses. This may be costly, and our investment would be lost if we cannot retain or reposition our sales and marketing personnel.

Regulation

Our product candidates and the activities associated with their development and commercialisation, including their design, testing, manufacture, safety, efficacy, recordkeeping, labelling, storage, approval, advertising, promotion, sale, distribution, import and export are subject to comprehensive regulation by the FDA and other regulatory agencies in the United States and by comparable authorities in other countries.

The process of obtaining marketing approvals, both in the United States and in other countries, is expensive and takes several years, if approval is obtained at all, and can vary substantially based upon a variety of factors, including the type, complexity and novelty of the product candidates involved. Failure to obtain marketing approval for a product candidate will prevent us from commercialising. We have not received approval to market any of our product candidates from regulatory authorities in any jurisdiction. We have limited experience in planning and conducting the clinical studies required for marketing approvals, and we expect to rely on third-party CROs to assist us in this process. Obtaining marketing approval requires the submission of extensive preclinical and clinical data and supporting information to regulatory authorities for each therapeutic indication to establish the product candidate’s safety and efficacy. Securing marketing approval also requires the submission of information about the product manufacturing process, and in many cases the inspection of manufacturing facilities by the regulatory authorities. Our product candidates may

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not be effective, may be only moderately effective or may prove to have undesirable or unintended side effects, toxicities or other characteristics that may preclude our obtaining marketing approval or prevent or limit commercial use. Regulatory authorities have substantial discretion in the new drug approval process and may refuse to accept any application or may decide that our data are insufficient for approval and require additional preclinical studies or clinical studies. Our product candidates could be delayed in receiving, or fail to receive, marketing approval.

Intellectual Property

If we are unable to obtain and maintain intellectual property protection for our technology and products, or if the scope of the intellectual property protection obtained is not sufficiently broad, our competitors could commercialise technology and products similar or identical to ours, and our ability to successfully commercialise our technology and products may be impaired. In addition, if we infringe the valid patent rights of others, we may be prevented from making, using or selling our products or may be subject to damages or penalties. Even if our patent applications issue as patents, they may not issue in a form that will provide us with any meaningful protection, prevent competitors from competing with us or otherwise provide us with any competitive advantage. Our competitors may be able to circumvent our owned or licensed patents by developing similar or alternative technologies or products in a non-infringing manner. We may become involved in administrative adversarial proceedings in the United States Patent and Trademark Office (USPTO) or in the patent offices of other countries brought by a third party to attempt to cancel or invalidate our patent rights, which could be expensive, time consuming and cause a loss of patent rights. We may have to file one or more lawsuits in court to prevent a third party from selling a product or using a product in a manner that infringes our patent, which could be expensive, time consuming and unsuccessful, and ultimately result in the loss of our proprietary market. Third parties may initiate legal proceedings alleging that we are infringing their intellectual property rights, the outcome of which would be uncertain and could hurt our business. We may not be able to effectively enforce our intellectual property rights throughout the world. Obtaining and maintaining our patent protection depends on compliance with various procedural, document submission, fee payment and other requirements imposed by governmental patent agencies, and our patent protection could be reduced or eliminated for non-compliance with these requirements. Our intellectual property licenses with third parties may be subject to disagreements over contract interpretation, which could narrow the scope of our rights to the relevant intellectual property or technology or increase our financial or other obligations to our licensors. We may be subject to claims by third parties asserting that our employees or we have misappropriated their intellectual property, or claiming ownership of what we regard as our own intellectual property. If we are unable to protect the confidentiality of our trade secrets, our business and competitive position would be harmed. Our proprietary information, or that of our suppliers and any future collaborators, may be lost or we may suffer security breaches. Intellectual property rights do not necessarily address all potential threats to our competitive advantage.

We may not have sufficient financial or other resources to adequately conduct litigation or proceedings relating to intellectual property claims. Some of our competitors may be able to sustain the costs of such litigation or proceedings more effectively than we can because of their greater financial resources and more mature and developed intellectual property portfolios. Accordingly, despite our efforts, we may not be able to prevent third parties from infringing upon, misappropriating or successfully challenging our intellectual property rights.

In 2018, we were granted a European patent from the European Patent Office, or EPO, European Patent 2955190, or EP 190, that covered the composition of matter of a genus of phosphoramidate nucleotide compounds that includes sofosbuvir, sold under the brand name Sovaldi^®, a leading drug for the treatment of hepatitis C sold by Gilead Sciences, Inc. Sofosbuvir is also a key component of Harvoni^®, Vosevi^® and Epclusa^®. Later in 2018, Gilead filed an Opposition to EP 190 at the EPO in an attempt to revoke it. In February 2021, the EPO Opposition Division disagreed with Gilead and upheld amended patent claims that cover sofosbuvir. In June 2021, the decision by the EPO Opposition Division to uphold our EP 190 was appealed by Gilead to the EPO Technical Boards of Appeal. We also filed an appeal to the EPO Technical Boards of Appeal against the decision by the EPO Opposition Division to only allow the patent in an amended form. On 24 March 2023, the EPO Technical Board of Appeal issued an oral decision revoking EP 190. This decision is final and has retroactive effect.

Subsequent to the decision of the Opposition Division, but also in February 2021, Gilead Sciences, Inc. and Gilead Sciences Limited filed a lawsuit against us in the Patents Court of the High Court of Justice of England and Wales requesting revocation of the U.K. part of EP 190. In March 2021, we filed a counterclaim against Gilead Sciences, Inc. and Gilead Sciences Limited alleging infringement of EP 190 resulting from acts including the sale of Sovaldi^®, as well as its combination products Harvoni^®, Vosevi^® and Epclusa^®, in the United Kingdom. In 2022, we were granted a further European patent from the EPO, EP 3904365, or EP 365, that covered the composition of matter of a smaller genus of phosphoramidate nucleotide compounds that includes sofosbuvir. Gilead Sciences, Inc. and Gilead Sciences Limited subsequently amended their claim to request revocation of the U.K. part of EP 365 and we counterclaimed for infringement. The U.K. Patents Court trial for this case took place between 20 January 2023 and 3 February 2023 and a judgement was handed down by the court on 21 March 2023. In its judgement, the High Court deemed that EP 190 and EP 365 were invalid in the United Kingdom. As a result of this decision, we reached a settlement with Gilead in relation to their legal fees for these legal proceedings in the United Kingdom.

In April 2021, we initiated legal proceedings against Gilead Sciences Ireland UC and Gilead Sciences GmbH in the German Regional Court of Dusseldorf for patent infringement for the sale of Sovaldi as well as its combination products Harvoni^®, Vosevi^® and Epclusa^® in Germany. In July 2022, the German Regional Court of Dusseldorf issued a judgment that Gilead Sciences Ireland UC and Gilead Sciences GmbH had infringed EP 190. Gilead appealed this decision and the Higher Regional Court of Dusseldorf appeal hearing had been scheduled for 17 August 2023. However, as a result of the decision in March 2023 by the EPO Technical Boards of Appeal, we abandoned all proceedings in Germany in May 2023 and, as a result, we reached a settlement with Gilead in relation to the legal fees for these legal proceedings in Germany.

Conduct of Clinical Studies

We rely on, and expect to continue to rely on, third parties to conduct our clinical studies for our product candidates. If these third parties do not successfully carry out their contractual duties, comply with regulatory requirements or meet expected deadlines, we may not be able to obtain marketing approval for or commercialise our product candidates, and our business could be substantially harmed. We do not have the ability to independently conduct clinical studies. Nevertheless, we will be responsible for ensuring that each of our clinical studies are conducted in accordance with the applicable protocol, legal and regulatory requirements and scientific standards.

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Employees

We currently have a limited number of employees, and our future success depends on our ability to retain key executives and to attract, retain and motivate qualified personnel. We are a clinical development-stage group, and, as of 31 December 2023, had 28 employees, including four executive officers. We are highly dependent on the research and development, clinical and business development expertise of Hugh Griffith, our founder and Chief Executive Officer, as well as the other principal members of our management team and our collaborators’ scientific and clinical teams. Recruiting and retaining qualified scientific, clinical, manufacturing, finance, sales and marketing personnel will also be critical to our success. The loss of the services of our executive officers or other key employees could impede the achievement of our research, development and commercialisation objectives and seriously harm our ability to successfully implement our business strategy.

environmental matters

We currently outsource our research, development and manufacturing activities.

Our leased offices in the United Kingdom drive the majority of our carbon emissions. The building currently has a current Energy Performance Certificate, with a Building Energy Performance Rating of “A” (between 0 to 15 kgCO₂ per m² per year). This rating is an improvement from the “C” rating indicated in NuCana’s previous annual report for the financial year ended 31 December 2022. The certificate has been produced under the Energy Performance of Buildings (Scotland) Regulations 2008 from data lodged to the Scottish EPC register. The building energy performance rating is a measure of the effect of a building on the environment in terms of carbon dioxide CO₂ emission, with ratings ranging between “A+” (net zero carbon) to “G” (very poor). The better the rating, the less impact on the environment. The current rating is based upon an assessor’s survey of the building, using EPCgen, V6.1.e.0.

Our report on greenhouse gas emissions is included in our Directors’ Report on page 16 of this Annual Report.

employees

The number of employees by function and geographic location at 31 December 2023 and 2022 was as follows:

As of 31 December 2023, we had 25 full-time employees and 3 part-time employees. We have never had a work stoppage and none of our employees are covered by collective bargaining agreements or represented by a labour union. We believe our employee relations are good.

Diversity

We make appointments based on merit according to the balance of skills and experience offered by prospective candidates. Whilst acknowledging the benefits of diversity, individual appointments are made irrespective of personal characteristics such as sex, race, disability, gender, sexual orientation, religion or age.

A breakdown of the statistics as at 31 December 2023 is as follows:

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employee consultation and human rights

We place considerable value on the involvement of our employees. Meetings are held with employees to discuss the operations and progress of the business and employees are encouraged to become involved in the success of the Group through share option schemes (see note 16 to the financial statements). We endeavour to impact positively on the communities in which we operate. We do not, at present, have a specific policy on human rights. However, we have several policies that promote the principles of human rights, including our Anti-Slavery and Human Trafficking Policy, which governs our zero-tolerance approach to modern slavery and our commitment to acting ethically and with integrity in all our business dealings; and an Anti-Corruption and Bribery Policy in order to reflect our policy to conduct our business in an honest and ethical manner. Our Health & Safety policy sets out our commitment to provision of a safe working environment for our employees. Furthermore, our Equal Opportunities Policy promotes the right of every employee to be treated with dignity and respect and not to be harassed or bullied on any grounds. Accordingly, we have a policy framework in place to ensure that we will respect the human rights of all our employees, including: provision of a safe, clean working environment; ensuring employees are free from discrimination and coercion; not using child or forced labour and respecting the rights of privacy and protecting access and use of employee personal information. This report does not contain information relating to social or community matters as such information is not relevant in understanding our development, performance, or position.

section 172(1) statement

Section 172 of the Companies Act 2006 requires each of directors to act in the way they consider, in good faith, would be most likely to promote the success of the company for the benefit of its members as a whole, and in doing so, have regard (amongst other matters) to:

The directors continue to have regard to the interests of our key stakeholders, including our shareholders, holders of ADSs, and employees. The Board recognises its responsibility to take into consideration the needs and concerns of all our stakeholders as part of our discussion and decision-making processes.

Details of our interactions and engagement with shareholders, ADSs holders and analysts are summarised below.

Our engagement and consultation with employees are outlined in the Employee Consultation and Human Rights section of this Strategic Report on page 13.

The consideration and impact of our operations on the environment are contained in the Environmental Matters section of this Strategic Report on page 12.

The Strategic Report was approved by the Board on 15 April 2024.

On behalf of the Board

Hugh S. Griffith

Chief Executive Officer

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02 directors’ report 14

14

directors’ report

Company registration

NuCana plc is registered in England and Wales with the registered number 03308778.

Results and dividends

The loss for the year after taxation amounted to £27.6 million (2022: £32.0 million). The directors do not recommend a final dividend (2022: £nil).

Principal activities

NuCana is a rapidly growing, clinical-stage biopharmaceutical Group developing a portfolio of new medicines (ProTides) to treat patients with cancer. The unique feature of ProTides is their ability to overcome the key limitations associated with many widely used anti-cancer medicines and have the potential to be more effective and safer treatments for patients with cancer.

Future developments

The future developments have been set out in the Strategic Report on page 2.

Research and development activities

NuCana’s research and development strategy and activities have been set out in the Strategic Report on pages 2 to 13.

Directors

The directors who served the Company during the year and up to the date of this report were as follows:

Going concern

The Group’s financial statements have been presented on the basis that it is a going concern. The Group has not generated any revenues from operations to date and does not expect to in the foreseeable future. As such, the Group has incurred recurring net losses, has an accumulated deficit totalling £207.7 million and cash flows used in operating activities of £26.4 million for the year ended 31 December 2023. The Group had £17.2 million of cash and cash equivalents at 31 December 2023.

The Group’s board of directors have reviewed the operating budgets and development plans for the 18-month period to 30 June 2025 (the “going concern assessment period”). The base case forecast prepared for the going concern assessment period includes assumptions regarding, among other things, research and development expenses, administrative expenses, staff costs and R&D tax credits. The timing of R&D tax credits is out with management’s control and any significant delay in receipt of these tax credits would result in the company exhausting its cash balances earlier than forecast within the going concern period. The forecast includes the post year end gross “at-the-market” (ATM) cash proceeds of £1.5 million disclosed in note 20 of the financial statements. The base case forecast has been reviewed and approved by the board of directors in accordance with the Group’s normal budgeting and forecasting processes.

Based on the base case forecast, the Group’s cash and cash equivalents on hand will not be sufficient to fund the Group’s anticipated operations for the entirety of the going concern assessment period. As the Group intends to continue to progress its research and development activities, there will be a requirement to seek additional capital within the going concern assessment period to fund operations, which the Group may obtain from additional equity financings, debt financings, partnerships or other sources.

If the Group is unable to obtain additional capital, the Group will be required to delay or reduce its research and development programs or cease trading which could negatively impact its ability to generate future sustainable operating revenues and profits or its ability to continue as a going concern.

The Group’s board of directors, having successfully completed several financings in the past, has prepared plans to raise additional capital and held preliminary discussions with potential financial advisers, and believe the Group will be successful in raising sufficient additional capital to allow the Group and the Company to continue as a going concern.

As a result of these matters there is material uncertainty related to the ability of the Group and the Company to raise sufficient additional capital within the going concern assessment period, prior to its cash balances being exhausted. These events or conditions give rise to a material uncertainty that may cast significant doubt upon the Group and the Company’s ability to continue as a going concern and, therefore, that it may be unable to realise its assets and discharge its liabilities in the normal course of business. The financial statements do not contain the adjustments that would result if the company was unable to continue as a going concern.

Financial instruments

Details of financial instruments are set out in note 18 to the financial statements on page 66.

Charitable and political contributions

No charitable contributions were paid during the 2023 financial year (2022: £nil).

No donations were made during the 2023 financial year to political organisations (2022: £nil).

Structure of group’s capital

Details of the structure of the Group’s capital are set out in note 14 to the financial statements on page 59.

Directors’ insurance and indemnities

The directors have the benefit of the indemnity provisions contained in the Company’s Articles of Association, and the Company has maintained throughout the year directors’ and officers’ liability insurance for the benefit of the Company, the directors and its officers. The Company has entered into qualifying third-party indemnity arrangements for the benefit of all its directors in a form and scope which comply with the requirements of the Companies Act 2006 and which were in force throughout the year and remain in force.

Overseas branches

The Company has no overseas branches.

Environmental matters

The Group measures and reports its greenhouse gas emissions.

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As 2020 was the first year of reporting, it is reported as the baseline year against which future performance is measured.

Quantification and reporting methodology

This report was compiled by management. The 2019 U.K. Government Environmental Reporting Guidelines and the GHG Protocol Corporate Accounting and Reporting Standard (revised edition) were followed to ensure the Streamlined Energy and Carbon Reporting (“SECR”) requirements were met.

The energy data was collated using existing reporting mechanisms for the Group’s leased offices in the United Kingdom, where the majority of the Group’s employees work. These methodologies provided a continuous record of electricity use.

The energy data was converted to carbon emissions using the 2023 U.K. Government GHG Conversion Factors for Company Reporting. The associated emissions are divided into the combustion of fuels and the operation of facilities (scope 1), purchased electricity, heating and cooling (scope 2) and indirect emissions that occur as a consequence of company activities (scope 3). During the year the Group only had emissions relating to scope 2.

Estimations

The electricity use was compiled from invoices and meter readings.

Intensity Ratio

The chosen primary intensity ratio is total gross emissions in metric tonnes CO₂e (mandatory emissions) per employee.

Energy efficiency action during current financial year

We will continue to monitor our carbon emissions and look for cost-effective improvements of energy performance.

Energy consumption is expected to be broadly stable this year as we continue to adopt a blended approach to working, with a mix of remote and office working. The COVID-19 pandemic has shown that more flexible working policies have not had a detrimental impact on the day-to-day function of the business. It is therefore expected that our energy consumption will be lower relative to pre-pandemic levels.

As a result of the COVID-19 pandemic, there has been a significant increase in the use of video conferencing for meetings, considerably reducing the need for travel. The emission savings resulting from these activities has not been quantified, but this practice has resulted in behavioural changes that are expected to continue for the foreseeable future.

Climate change

The Group relies on third parties to manufacture and ship our product candidates for preclinical studies and clinical studies, as well as conducting the associated preclinical and clinical studies. As a result, the Group’s direct operational footprint is such that it does not expect any material impact on their operations and financial position as a result of climate change.

The Audit Committee makes recommendations to the Board on the principal risks of relevance to the business. Climate-related issues are considered in terms of potential for contribution to these principal risks. The issues considered include both the risk of physical disruption to the business from climate change, and the risks and opportunities as the global economy transitions to significantly lower carbon emissions. In the current period, the Audit Committee concluded that climate-related risks did not rise to the level of a principal risk.

Events after the reporting period

Details of important events affecting the Group, which have occurred since 31 December 2023, are set out in note 20 to the financial statements on page 67.

Disclosure of information to the auditors

So far as each person who was a director at the date of approving this report is aware, there is no relevant audit information, being information needed by the auditor in connection with preparing its report, of which the auditor is unaware. Having made enquiries of fellow directors and the Group’s auditor, each director has taken all the steps that they are obliged to take as directors in order to make themselves aware of any relevant audit information and to establish that the auditor is aware of that information.

Auditors

Resolutions to re-appoint Ernst & Young LLP as auditor of the Company and to authorise the Board to set its remuneration will be proposed at the Company’s forthcoming annual general meeting (“AGM”).

The Directors’ Report was approved by the Board on 15 April 2024.

On behalf of the Board

Hugh S. Griffith

Director

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03 directors’ remuneration report

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remuneration committee chair’s annual statement

The information provided in this part of the Directors’ Remuneration Report is not subject to audit.

On behalf of the Board of Directors of NuCana plc, I am pleased to present the Directors’ Remuneration Report for the year ended 31 December 2023.

Voting at our 2023 AGM was conducted on a show of hands by those shareholders (or their proxies, as applicable) in attendance at the relevant meeting. At the meeting, the resolutions to approve the 2022 Directors’ Remuneration Report and the Directors’ Remuneration Policy were each approved by a majority of the votes cast at the meeting on a show of hands. Had a poll been called the proxy vote directions given to the Chairman of the 2023 AGM (and other officers of the Company) would have been exercised as follows:

A copy of the Directors’ Remuneration Policy (approved to take effect from 15 June 2023) is available for inspection at the Global Headquarters of the Company at 3 Lochside Way, Edinburgh, EH12 9DT, United Kingdom, and is also available on pages 25 to 29 of our 2022 Annual Report, which is on our website at http://www.nucana.com.

Remuneration Committee

The Remuneration Committee consists of two independent Non-Executive Directors, Bali Muralidhar (Chair from 27 April 2022 and Member since 5 February 2021), and Elliott Levy (Member since 6 May 2022).

The Remuneration Committee is responsible for reviewing and establishing our executive remuneration policy and philosophy, including reviewing the performance of the senior executive officers and setting the scale and structure of their remuneration and the basis of their service agreements with due regard to the interests of the shareholders. It is the policy of the Remuneration Committee that no individual can participate in discussions or decisions concerning his or her own remuneration.

The Directors’ Remuneration Report that follows is for the year from 1 January 2023 to 31 December 2023 except where otherwise stated.

The Directors’ Remuneration Policy is designed to:

Activities and major decisions

During the year ended 31 December 2023, the Committee undertook the following activities and major decisions:

As a result of the review completed in 2023, the Chief Executive Officer (CEO), Chief Financial Officer (CFO) and Chief Medical Officer (CMO) received increased base salary awards at a level that is broadly aligned with historical peer group comparator data.

2024 Annual General Meeting

On behalf of the Board, I wish to thank our shareholders for their input and support during the year ended 31 December 2023. The Remuneration Committee and the Board of Directors welcome feedback from our shareholders on the Directors’ Remuneration Report. We look forward to receiving the support of our shareholders for the Directors’ Remuneration Report at our Annual General Meeting to be held on 18 June 2024.

report on remuneration

The information provided in this part of the Directors’ Remuneration Report is subject to audit.

The Remuneration Committee presents the Report on Remuneration for the year ended 31 December 2023, which will be put to shareholders for a non-binding vote at the Annual General Meeting to be held on 18 June 2024.

Single total figure for Remuneration of each Director

The following table shows the remuneration received by the directors for the years ended 31 December 2023 and 31 December 2022.

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Annual bonus

Our Executive Directors are eligible for an annual bonus at the discretion of the Remuneration Committee. Bonus awards are reviewed at the end of each calendar year and any such awards are determined by the performance of the individual and the company as a whole, based upon the achievement of strategic objectives set at the beginning of the year. In determining Executive Director compensation for the year ended 31 December 2023, the Remuneration Committee considered achievement of specific performance measures which had been previously approved by the Remuneration Committee to be achieved by the executive team during 2023. These are considered to be commercially sensitive and will not be disclosed in detail, but are linked to our business strategies which include to:

Share options awarded during the financial year

The table below shows, for each director, the total number of options awarded in the year ended 31 December 2023. The face value of the award is calculated as the share price at date of grant, in pounds sterling, multiplied by the number of options granted. The options granted have no performance conditions, only service conditions.

We periodically grant share options to employees, directors and consultants to enable them to share in our successes and to reinforce a corporate culture that aligns their interests with that of our shareholders.

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Statement of directors’ shareholdings and share interests

The table below shows, for each director, the total number of shares owned, the total number of share options held and the number of share options vested as at 31 December 2023. The table only reflects shares held individually by each director and does not include shares held by any investment fund with which the director is affiliated.

Policy on shareholding requirements

We do not currently have a policy requiring our directors to hold a certain number or value of our shares.

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Directors’ equity-based awards held at 31 December 2023

The table below presents the interests of the directors in options to acquire our ordinary shares with a nominal value of £0.04 per share as at 31 December 2023. A total of 1,179,150 options were granted to directors during the year ended 31 December 2023. Two of our directors exercised options during the year ended 31 December 2023.

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The closing market price of our ADSs on 31 December 2023 was $0.30. One ADS represents one ordinary share.

Payments made to past directors

During the year ended 31 December 2023, no payments were made to former directors of the Company.

Payments for loss of office

During the year ended 31 December 2023, no payments were made with respect to a director’s loss of office.

Policy on payments for loss of office

Our approach to payments in the event of termination of an Executive Director is to take account of the individual circumstances including the reason for termination, individual performance, contractual obligations and the terms of the share option scheme in which the Executive Director participates.

Payment obligations would include base salary, target bonus and benefits. In addition, our option scheme rules allow some or all of the options held by our Executive Directors and senior executive officers to vest in certain circumstances upon the event of a change of control.

There are no contractual provisions agreed prior to 27 June 2012 that could impact on the quantum of the payment.

We will comply with applicable disclosure and reporting requirements of the Securities and Exchange Commission with respect to remuneration arrangements with a departing Executive Director.

Illustration of total shareholder return

The information provided in this part of the Directors’ Remuneration Report is not subject to audit.

The graph below shows the daily movements by 31 December 2023, of $100 invested in NuCana plc ADS at our IPO price on 28 September 2017 compared with the value of $100 invested in the SPDR Series Trust SPDR S&P Biotech ETF (XBI). We believe this graph reflects our relative performance against a group of similarly situated comparator companies.

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Chief Executive Officer historical remuneration

The table below sets out total remuneration delivered to the Chief Executive Officer over the last eight years valued using the methodology applied to the single total figure of remuneration. The Remuneration Committee does not believe that the remuneration payable in its earlier years as a private company bears any comparative value to that paid in its later years and therefore the Remuneration Committee has chosen to disclose remuneration only for the eight most recent financial years.

Change in director remuneration compared to other employees

The following table below shows the percentage change in the remuneration of directors and the average change per employee from 2020 onwards.

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Relative importance of spend on pay

The following table sets forth the total amounts spent by the Group on remuneration for the year ended 31 December 2023 and the year ended 31 December 2022. The comparator chosen to reflect the relative importance of the Group’s spend on pay is the Group’s research and development expenses as shown in its consolidated income statement on page 38 of its Annual Report and Financial Statements for the year ended 31 December 2023. Dividend distribution and share buyback comparators have not been included as the Group has no history of such transactions.

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statement of implementation of the directors’ remuneration policy in financial year ending 31 December 2024

In January 2024, the Remuneration Committee considered the extent to which the 2023 calendar year objectives were achieved by the executive team and determined the level of bonus incentive awards payable in respect of the 2023 calendar year. The awards made to our CEO and senior executive officers recognised that the vast majority of our corporate objectives, including stretch objectives and goals, for 2023 had been achieved, with our CEO and senior executive officers receiving bonus awards at 98.7% of the potential target bonus amount. These target bonus amounts had also been benchmarked against peer group comparative data provided by Radford in previous years.

In January 2024, the Committee met to consider the award of share options to the Directors and CEO in respect of services provided and performance attained during 2023, in accordance with the Remuneration Policy. Further details will be provided in the 2024 Annual Report.

In January 2024, the Committee determined that the executive team should continue to focus on achieving the Company’s core objectives during 2024. These are considered to be commercially sensitive and will not be disclosed in detail, but are linked to our business strategies which include to:

The Remuneration Committee

The Remuneration Committee consists of two independent Non-Executive Directors, Bali Muralidhar and Elliott Levy.

Each of these Non-Executive Director members is a non-employee director as defined in Rule 166-3 under the Securities Exchange Act of 1934, as amended, and an outside director as defined in Section 162(m) of the Internal Revenue Code of 1986, as amended. Bali Muralidhar serves as Chairperson of the Remuneration Committee. The Remuneration Committee reviews, among other things, the performance of the executive officers and sets the scale and structure of their remuneration and the basis of their service agreements with due regard to the interests of the shareholders.

It is a policy of the Remuneration Committee that no individual participates in discussions or decisions concerning his or her own specific remuneration (although the members of the Remuneration Committee do consider the remuneration generally of the Non-Executive Directors as a class).

All members have continued to serve until the date of this Report on Remuneration. The terms of reference of the Remuneration Committee is set forth on our website at http://www.nucana.com.

Advice provided to the Remuneration Committee

The Remuneration Committee had retained Radford, an Aon Hewitt company, in previous years to provide independent advice and consultation with respect to remuneration arrangements for the CEO, CFO, CMO and Non-Executive Directors. For the year ended 31 December 2023 Radford were not engaged, but the Remuneration Committee relied on their previous consistent advice from earlier years. Radford are global remuneration consultants with a well-established reputation for the design and implementation of remuneration programmes, including the design and implementation of equity-based award programmes. Radford have no other connection to, or business relationship with, NuCana. Based on Radford’s extensive experience with similar assignments and the fact that Radford have no other connections to, or business relationships, with NuCana, the Remuneration Committee believes the advice received in the past from Radford is objective and independent.

In addition, the Remuneration Committee solicited and received input from the CEO concerning the remuneration of employees other than himself. The CEO provided recommendations with respect to annual cash bonuses to be paid to these persons for service in the year ending 31 December 2023 and base salary awards effective from 1 January 2024. Finally, the CEO also provided input to the Remuneration Committee regarding the implementation of equity-based remuneration as an element of all other employees’ remuneration.

Approval

This report was approved by the Board of Directors on 15 April 2024 and signed on its behalf by:

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statement of directors’ responsibilities

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statement of directors’ responsibilities

The directors are responsible for preparing the Strategic Report, the Directors’ Report, the Directors’ Remuneration Report and the financial statements in accordance with applicable United Kingdom law and regulations. Company law requires the directors to prepare financial statements for each financial year. Under that law the directors have elected to prepare the financial statements in conformity with International Financial Reporting Standards (“IFRS”) as issued by the International Accounting Standards Board (“IASB”) and in conformity with U.K.-adopted international accounting standards.

Under Company law, the directors must not approve the financial statements unless they give a true and fair view of the state of affairs of the Group and Company and of the profit or loss of the Group and Company for that period. In preparing those financial statements the directors are required to:

The directors are responsible for keeping adequate accounting records that are sufficient to show and explain the Group’s and Company’s transactions and disclose with reasonable accuracy at any time the financial position of the Group and Company and enable them to ensure that the financial statements comply with the Companies Act 2006. They are also responsible for safeguarding the assets of the Group and the Company and hence for taking reasonable steps for the prevention and detection of fraud and other irregularities.

The directors are responsible for the maintenance and integrity of the corporate and financial information included on the Company’s website.

The names of the directors are set out on page 15 of this report.

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independent report auditor’s to the members of NuCana plc

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