NUCANA PLC UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS For the Three Months Ended June 30, For the Six Months Ended June 30, Notes 2025 2024 2025 2024 (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. On August 11, 2025, the Company effected a ratio change of its ADSs to its ordinary shares from one ADS representing 25 ordinary shares, to one ADS representing 5,000 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, 2024 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 six months ended June 30, 2025 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, 2024, except as described below.

In May 2025, the Company completed a registered direct offering of ADSs, pre-funded

warrants, and accompanying Series A and Series B warrants. The pre-funded

warrants, Series A and Series B warrants are classified as derivative financial liabilities and measured at fair value through profit or loss in accordance with IFRS 9 and IAS 32. These warrants are remeasured prior to each exercise and at the end of the reporting period, with changes in fair value recognized within finance expense in the consolidated statement of operations. Due to the complexity of the instruments' terms, fair value has been determined using a combination of approaches, including the Black-Scholes Option Pricing model and the Company's share price at the measurement date.

No new standards, amendments or interpretations have had an impact on the financial statements for the six months ended June 30, 2025. The financial statements comprise the financial statements of the Group at June 30, 2025. 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, 2024.

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 six months ended June 30, 2025 are not necessarily indicative of the results that can be expected for the Company's fiscal year ending December 31, 2025.

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 250.7 million and cash flows used in operating activities of 7.6 million as of and for the six months ended June 30, 2025. The Company had 8.4 million of cash and cash equivalents at June 30, 2025.

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 together with the gross cash proceeds subsequently raised from the "at-the-market"

(ATM) offering of 19.0 million disclosed in note 11, will be sufficient to fund our anticipated operations for the entirety of the going concern assessment period. The board of directors is therefore satisfied that it is appropriate to adopt the going concern basis of accounting in preparing the financial statements.

As the Company continues to incur losses, the transition to profitability is dependent upon the successful development, approval and commercialization of its product candidates and achieving a level of revenues adequate to support its cost structure. The Company may never achieve profitability, and unless and until it does, it will continue to need additional capital. There can be no assurances, however, that additional funding will be available on acceptable terms.

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, 2024 except as described below.

Significant judgement was required in determining the classification and fair value measurement of the pre-funded

warrants, Series A warrants, and Series B warrants issued in connection with the registered direct offering in May 2025. Management concluded that the warrants should be classified as derivative financial liabilities under IAS 32, as they do not meet the "fixed-for-fixed"

equity classification criteria. This is due to certain features such as reset mechanisms, the "zero exercise price" option attached to the warrants, and the fact that the warrants are denominated in US dollars while the Company's functional currency is pounds sterling.

The valuation of the warrants represents a key accounting estimate due to the significant judgement involved in determining fair value. The warrants are measured at fair value through profit or loss immediately prior to each exercise and at each reporting date. Due to the complexity of the instruments' terms, fair value has been determined using a combination of approaches, including the Black-Scholes Option Pricing model and the Company's share price at the measurement date. The valuation incorporates various observabl

e inputs, including hist

orical volatility of the Company's ADSs, expected life of the warrants, risk-free interest rates, and probabilities associated with certain market-based conditions. Changes in these assumptions can result in significant variation in fair value. At each revaluation date, management review the valuation methodology and key inputs used in the model and update them as appropriate.

loss from derivative financial instruments of 12.6 million relates to the remeasurement of Series A and Series B warrants.

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.

5. 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.

6. Intangible assets

Intangible assets comprise patents with a carrying value of 2.2 million as of June 30, 2025 (as of December 31, 2024: 2.2 million).

During the six months ended June 30, 2025, the Company acquired intangible assets with a cost of 0.1 million in relation to patents.

7. 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.

8. 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 years.

As detailed in the table below, during the six months ended June 30, 2025, 3,478,076,733 share options were granted under the 2020 Long-Term Incentive Plan (six months ended June 30, 2024: 6,273,782). 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.

During the three months ended June 30, 2025, the Company cancelled 14,380,933 share options granted under the 2016 Share

Option Scheme and 2020 Long-Term Incentive Plan (three months ended June 30, 2024: nil). The incremental fair value of the new options was 13.5 million, calculated using the Black-Scholes model fair value of cancelled options at the date of cancellation compared with the fair value at grant date of new options awarded.

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.

For the three months ended June 30, 2025, the Company recognized 8.0 million of share-based payment expense in the statement of operations (three months ended June 30, 2024: 0.7 million). For the six months ended June 30, 2025, the Company recognized 8.2 million of share-based payment expense in the statement of operations (six months ended June 30, 2024: 1.3 million).

9. Share capital and share premium

On April 23, 2025, the Company subdivided and redesignated the issued share capital of 151,923,897 ordinary shares of 0.04 each into 151,923,897 ordinary shares and 15,040,465,803 deferred shares, in each case, of 0.0004 each. The deferred shares have no economic value, dividend or voting rights.

10. Derivative financial instruments

In May 2025, the Company completed a registered direct offering comprising 2,452,935 ADSs, representing 61,323,375 ordinary shares, and 8,393,050 pre-funded

warrants, representing 209,826,250 ordinary shares, with each ADS or pre-funded

warrant accompanied by one Series A and Series B warrant to purchase one ADS. Of the 5.2 million initial proceeds, 4.4 million was allocated to the warrants, which were classified as derivative financial instruments. Both Series A and Series B warrants contained a net settlement option and a reset mechanism allowing the exercise price to be adjusted with a proportional adjustment to the number of warrants outstanding, such that the aggregate exercise price payable remained the same. In addition, the Series B warrants included a "zero exercise price" option, allowing the holder, upon payment of the nominal value, to receive three ADSs for each warrant, based on the number that would have been issued under a traditional cash exercise.

During the period, all 8,393,050 pre-funded

warrants issued in the offering were exercised for gross proceeds of 0.1 million. Following the offering, the exercise price of the Series B warrants was reset from $1.61 to $0.3643 and subsequently to the floor price of $0.1291, increasing the number of Series B warrants to 118,804,235. During the three months ended June 30, 2025 all Series B warrants were exercised under the "zero exercise price" option. This resulted in the issuance of 356,412,705 ADSs, representing 8,901,317,625 ordinary shares, and gross proceeds of 3.5 million, representing the nominal value of the ADSs issued. The exercise price of the Series A warrants was also reset to the floor price of $0.1291, increasing the number of Series A warrants to 67,781,105. As of June 30, 2025, 8,300,000 Series A warrants, representing 207,500,000 ordinary shares had been exercised for gross proceeds of 0.8 million. The total fair value of all options exercised during the period was 14.5 million.

The closing balance of 2.6 million relates to the fair value of the Series A warrants that were outstanding as of June 30, 2025. The fair value of these warrants reflects the terms of a cancellation agreement entered into on June 27, 2025, under which the Company and the warrant holders agreed to cancel the outstanding Series A warrants in exchange for a fixed cash payment. As a result, the valuation at June 30, 2025 was based on the expected economic outflow under this agreement, rather than the Black-Scholes Option Pricing model.

11. Events after the reporting period

Subsequent to June 30, 2025, the Company sold and issued 450,758,552 ADSs, representing 11,268,963,800 ordinary shares, under the ATM program, raising gross proceeds of 19.0 million.

In July 2025, the Company cancelled all remaining Series A warrants, totaling 59,481,105, in exchange for a payment to warrant holders of 2.7 million ($3.6 million).