NUCANA PLC UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS For the Three Months Ended June 30, For the Six Months Ended June 30, Notes 2024 2023 2024 2023 (in thousands, except per share data) Research and deve

UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS

The accompanying notes form an integral part of these unaudited condensed consolidated financial statements.

UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS

The accompanying notes form an integral part of these unaudited condensed consolidated financial statements.

UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF FINANCIAL POSITION

The accompanying notes form an integral part of these unaudited condensed consolidated financial statements.

UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY

The accompanying notes form an integral part of these unaudited condensed consolidated financial statements.

UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS

The accompanying notes form an integral part of these unaudited condensed consolidated financial statements.

NOTES TO THE UNAUDITED CONDENSED CONSOLIDATED FINANCIAL STATEMENTS

1. General information

NuCana plc ("NuCana" or the "Company") is a clinical-stage biopharmaceutical company developing a portfolio of new medicines to treat patients with cancer. NuCana is harnessing the power of phosphoramidate chemistry to generate new medicines called ProTides. These compounds have the potential to improve cancer treatment by enhancing the efficacy and safety of several current standards of care.

The Company has had American Depository Shares ("ADSs") registered with the US Securities and Exchange Commission ("SEC") and has been listed on Nasdaq since October 2, 2017. From November 9, 2023 the Company transferred its listing to The Nasdaq Capital Market. On April 16, 2024, the Company effected a ratio change of its ADSs to its ordinary shares from one ADS representing one ordinary share, to one ADS representing 25 ordinary shares.

The Company is incorporated in England and Wales and domiciled in the United Kingdom. The Company's registered office is located at 77/78 Cannon Street, London EC4N 6AF, United Kingdom and its principal place of business is located at 3 Lochside Way, Edinburgh, EH12 9DT, United Kingdom.

The Company has three

wholly owned subsidiaries, NuCana, Inc., NuCana Limited and NuCana BioMed Trustee Company Limited (together referred to as the "Group").

The financial information presented in these unaudited condensed consolidated financial statements does not constitute the Group's statutory accounts within the meaning of section 434 of the U.K. Companies Act 2006.

The Group's statutory accounts for the year ended December 31, 2023 have been reported on by the Company's auditor, and delivered to the Registrar of Companies. The report of the auditor was (i) unqualified and (ii) did not include a reference to any matters to which the auditors drew attention by way of emphasis without qualifying their report. However, the report of the auditor did include a material uncertainty related to going concern disclosure.

2. Material accounting policies

Basis of preparation

The unaudited condensed consolidated financial statements (the "financial statements") for the three months and six months ended June 30, 2024 have been prepared in accordance with International Accounting Standard 34, "Interim Financial Reporting"

("IAS 34"). The material accounting policies and methods of computation applied in the preparation of the financial statements are consistent with those applied in the Company's annual financial statements for the year ended December 31, 2023. No new standards, amendments or interpretations have had an impact on the financial statements for the three months and six months ended June 30, 2024. The financial statements comprise the financial statements of the Group at June 30, 2024. The financial statements are presented in pounds sterling, which is also the Company's functional currency. All values are rounded to the nearest thousand, except where otherwise indicated.

The financial statements do not include all the information and disclosures required in the annual financial statements, and should be read in conjunction with the Company's annual financial statements for the year ended December 31, 2023.

In the opinion of management, these unaudited condensed consolidated financial statements include all normal recurring adjustments necessary for a fair statement of the results of operations, financial position and cash flows. The results of operations for the three months and six months ended June 30, 2024 are not necessarily indicative of the results that can be expected for the Company's fiscal year ending December 31, 2024.

The Company's consolidated financial statements have been presented on the basis that it is a going concern. The Company has not generated any revenues from operations to date and does not expect to in the foreseeable future. As such, the Company has incurred recurring losses, has an accumulated deficit totaling 219.4 million and cash flows used in operating activities of 7.1 million as of and for the six months ended June 30, 2024. The Company had 11.6 million of cash and cash equivalents at June 30, 2024.

In reviewing the going concern assessment the Company's board of directors have considered a going concern period of 12-months

from the issuance of these financial statements. Based on our current operating plan, our cash and cash equivalents on hand will not be sufficient to fund our anticipated operations for the entirety of the going concern assessment period. As the Company intends to continue to progress its research and development activities, there will be a requirement to seek additional capital within the going concern period to fund operations, which the Company may obtain from additional equity financings, debt financings or other sources. If the Company is unable to obtain additional capital, the Company will be required to delay or reduce its research and development programs which could negatively impact its ability to generate future sustainable operating revenues and profits.

As a result of these matters, there is uncertainty related to the ability of the Company to raise sufficient additional capital within the going concern period, prior to its cash balances being exhausted. These events or conditions raise substantial doubt about the Company's ability to continue as a going concern and, therefore, that the Company may be unable to realize its assets and discharge its liabilities in the normal course of business. The consolidated financial statements do not include any adjustments that might result from the outcome of this uncertainty.

Judgements and estimates

The accounting estimates and judgements made by management in applying the Group's accounting policies that have the most material effect on the amounts included within these financial statements were the same as those that applied to the annual financial statements for the year ended December 31, 2023.

The income tax credit recognized primarily represents the U.K. research and development tax credits. In the United Kingdom, the Company is able to surrender some of its losses for a cash rebate of up to 26.97% of expenditure related to eligible research and development projects incurred on or after April 1, 2023 (33.35% prior to April 1, 2023).

4. Basic and diluted loss per ordinary share

Basic loss per ordinary share is calculated by dividing the loss for the period attributable to the equity holders of the Company by the weighted average number of ordinary shares outstanding during the period.

The potential ordinary shares issued through equity settled transactions were considered to be anti-dilutive as they would have decreased the loss per ordinary share and were therefore excluded from the calculation of diluted loss per ordinary share.

5. Intangible assets

Intangible assets comprise patents with a carrying value of 2.2 million as of June 30, 2024 (as of December 31, 2023: 2.1 million).

During the six months ended June 30, 2024, the Company acquired intangible assets with a cost of 0.2 million in relation to patents.

6. Cash and cash equivalents

Cash and cash equivalents comprise cash at banks with deposit maturity terms of three months or less. Cash at banks earns interest at fixed or variable rates based on the terms agreed for each account.

7. Share-based payments

The Company has six share-based payment plans for employees, directors and consultants. The share options granted will be settled in equity. If the Company determines, and at its discretion, an arrangement may be made under the 2020 Long-Term Incentive Plan to substitute the right to acquire shares with a cash alternative of equivalent value. Options granted under each of the six plans have a maximum life of 10

As detailed in the table below, during the six months ended June 30, 2024, 6,273,782 share options were granted under the 2020 Long-Term Incentive Plan (six months ended June 30, 2023: 2,695,639 share options granted). Options granted under this plan will vest if the option holder remains under respective contract of employment or contract of service for the agreed vesting period. The share options granted in the period will vest over a period of up to four years. Upon vesting, each option allows the holder to purchase one ordinary share at a specified option price determined at grant date. Options granted as RSU-style

options are automatically exercised on vesting.

The fair values of options granted were determined using the Black-Scholes model that takes into account factors specific to the share incentive plan such as the assumption that the options are exercised at a point in time of up to two years after vesting. This has been incorporated into the measurement by means of actuarial modelling.

Represents the average for the options granted.

For the three months ended

June 30, 2024, the Company recognized

0.7 million of share-based payment expense in the statement of operations (three months ended June 30, 2023: 1.1 million). For the six months ended June 30, 2024, the Company has recognized 1.3 million of share-based payment expense in the statement of operations (six months ended June 30, 2023: 2.2 million).

8. Share capital and share premium