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Registered number: 13157735 THIRTYFIVEBIO LIMITED UNAUDITED FINANCIAL STATEMENTS FOR THE YEAR ENDED 31 DECEMBER 2024
THIRTYFIVEBIO LIMITED CONTENTS
| Page
Company information | 1
Balance sheet | 2 - 3
Notes to the financial statements | 4 - 12
THIRTYFIVEBIO LIMITED COMPANY INFORMATION
Directors | Mr B K Ahrens
| Dr N Lonberg
| Dr T D McCarthy
| Mr J Westcott
| Dr D D M Leung
Company secretary | S A Harris
Registered number | 13157735
Registered office | 99 Park Drive
| Milton
| Abingdon
| OX14 4RY
Accountants | Blick Rothenberg Limited
| Chartered Accountants
| 16 Great Queen Street
| Covent Garden
| London
| WC2B 5AH
Page 1
|  | REGISTERED NUMBER:13157735
THIRTYFIVEBIO LIMITED BALANCE SHEET AS AT 31 DECEMBER 2024
|  | 2024 |  | 2023
Note |  | £ |  | £
Fixed assets |  |  |  |  |
Tangible assets | 4 |  | 8,487 |  | 20,104
Investments | 5 |  | 1 |  | 1
|  |  | 8,488 |  | 20,105
Current assets |  |  |  |  |
Debtors: amounts falling due within one year | 6 | 623,604 |  | 831,463 |
Cash at bank and in hand |  | 353,078 |  | 1,956,838 |
|  | 976,682 |  | 2,788,301 |
Creditors: amounts falling due within one year | 7 | (996,839) |  | (408,567) |
Net current (liabilities)/assets |  |  | (20,157) |  | 2,379,734
Net (liabilities)/assets |  |  | (11,669) |  | 2,399,839
Capital and reserves |  |  |  |  |
Called up share capital | 8 |  | 405 |  | 403
Share premium account |  |  | 14,638,172 |  | 14,638,172
Capital redemption reserve |  |  | (2) |  | (2)
Profit and loss account |  |  | (14,650,244) |  | (12,238,734)
Total (deficit)/equity |  |  | (11,669) |  | 2,399,839
Page 2
|  | REGISTERED NUMBER:13157735
THIRTYFIVEBIO LIMITED BALANCE SHEET (CONTINUED) AS AT 31 DECEMBER 2024 The directors consider that the company is entitled to exemption from audit under section 477 of the Companies Act 2006 and members have not required the company to obtain an audit for the year in question in accordance with section 476 of the Companies Act 2006. The directors acknowledge their responsibilities for complying with the requirements of the Companies Act 2006 with respect to accounting records and the preparation of financial statements. The financial statements have been prepared in accordance with the provisions applicable to companies subject to the small companies regime and in accordance with the provisions of FRS 102 Section 1A - small entities. The financial statements have been delivered in accordance with the provisions applicable to companies subject to the small companies regime. The company has opted not to file the profit and loss account in accordance with provisions applicable to companies subject to the small companies' regime. The financial statements were approved and authorised for issue by the board and were signed on its behalf by:
Mr J Westcott
Director
Date: 10 October 2025
The notes on pages 4 to 12 form part of these financial statements. Page 3
THIRTYFIVEBIO LIMITED NOTES TO THE FINANCIAL STATEMENTS FOR THE YEAR ENDED 31 DECEMBER 2024
1. | General information
ThirtyFiveBio Limited is a private company limited by shares incorporated in England and Wales. The address of its registered office is 99 Park Drive, Milton, Abingdon, England, OX14 4RY. The financial statements are presented in Sterling (£), which is the functional currency of the company. Monetary amounts in these financial statements are rounded to the nearest £. 2.Accounting policies
| 2.1 | Basis of preparation of financial statements
The financial statements have been prepared under the historical cost convention unless otherwise specified within these accounting policies and in accordance with Section 1A of Financial Reporting Standard 102, the Financial Reporting Standard applicable in the UK and the Republic of Ireland and the Companies Act 2006. The following principal accounting policies have been applied:
| 2.2 | Exemption from preparing consolidated financial statements
The company, and the group headed by it, qualify as small as set out in section 383 of the Companies Act 2006 and the parent and group are considered eligible for the exemption to prepare consolidated accounts. The financial statements present information about the company as an individual entity and not about its group.
| 2.3 | Going concern
Losses will continue to be generated in the year to 31 December 2025 as the company is in its research and development phase and operating in line with its business plan. The company has carried out regular fundraising exercises to date in order to provide the necessary capital for the company, including $2.5m received between January 2025 and March 2025. The directors expect to continue to raise additional funding. Should future fundraising be lower than anticipated the directors will reduce the planned expenditure, as necessary. The directors estimate that the cash held by the company together with known receivables will be sufficient to support the current level of activities. The directors therefore have a reasonable expectation that the company will have adequate resources to continue in operational existence and meet its liabilities as they fall due for the foreseeable future, being a period of at least twelve months from the date of approval of these financial statements. Accordingly, the financial statements have been prepared on a going concern basis. Page 4
THIRTYFIVEBIO LIMITED NOTES TO THE FINANCIAL STATEMENTS FOR THE YEAR ENDED 31 DECEMBER 2024 2.Accounting policies (continued)
| 2.4 | Foreign currency translation
Functional and presentation currency The company's functional and presentational currency is £. Transactions and balances Foreign currency transactions are translated into the functional currency using the spot exchange rates at the dates of the transactions. At each period end foreign currency monetary items are translated using the closing rate. Non-monetary items measured at historical cost are translated using the exchange rate at the date of the transaction and non-monetary items measured at fair value are measured using the exchange rate when fair value was determined. Foreign exchange gains and losses resulting from the settlement of transactions and from the translation at period-end exchange rates of monetary assets and liabilities denominated in foreign currencies are recognised in profit or loss except when deferred in other comprehensive income as qualifying cash flow hedges. Foreign exchange gains and losses that relate to borrowings and cash and cash equivalents are presented in the profit and loss account within 'finance income or costs'. All other foreign exchange gains and losses are presented in profit or loss within 'other operating income'.
| 2.5 | Research and development
In the research phase of an internal project it is not possible to demonstrate that the project will generate future economic benefits and hence all expenditure on research shall be recognised as an expense when it is incurred. Intangible assets are recognised from the development phase of a project if and only if certain specific criteria are met in order to demonstrate the asset will generate probable future economic benefits and that its cost can be reliably measured. The capitalised development costs are subsequently amortised on a straight-line basis over their useful economic lives, which range from 3 to 6 years. If it is not possible to distinguish between the research phase and the development phase of an internal project, the expenditure is treated as if it were all incurred in the research phase only.
| 2.6 | Interest income
Interest income is recognised in profit or loss using the effective interest method.
| 2.7 | Finance costs
Finance costs are charged to profit or loss over the term of the debt using the effective interest method so that the amount charged is at a constant rate on the carrying amount. Issue costs are initially recognised as a reduction in the proceeds of the associated capital instrument.
| 2.8 | Borrowing costs
All borrowing costs are recognised in profit or loss in the year in which they are incurred. Page 5
THIRTYFIVEBIO LIMITED NOTES TO THE FINANCIAL STATEMENTS FOR THE YEAR ENDED 31 DECEMBER 2024 2.Accounting policies (continued)
| 2.9 | Pensions
Defined contribution pension plan The company operates a defined contribution plan for its employees. A defined contribution plan is a pension plan under which the company pays fixed contributions into a separate entity. Once the contributions have been paid the company has no further payment obligations. The contributions are recognised as an expense in profit or loss when they fall due. Amounts not paid are shown in accruals as a liability in the balance sheet. The assets of the plan are held separately from the company in independently administered funds.
| 2.10 | Tangible fixed assets
Tangible fixed assets under the cost model are stated at historical cost less accumulated depreciation and any accumulated impairment losses. Historical cost includes expenditure that is directly attributable to bringing the asset to the location and condition necessary for it to be capable of operating in the manner intended by management. At each reporting date the company assesses whether there is any indication of impairment. If such indication exists, the recoverable amount of the asset is determined which is the higher of its fair value less costs to sell and its value in use. An impairment loss is recognised where the carrying amount exceeds the recoverable amount. The company adds to the carrying amount of an item of fixed assets the cost of replacing part of such an item when that cost is incurred, if the replacement part is expected to provide incremental future benefits to the company. The carrying amount of the replaced part is derecognised. Repairs and maintenance are charged to profit or loss during the period in which they are incurred. Depreciation is charged so as to allocate the cost of assets less their residual value over their estimated useful lives, using the straight-line method. The estimated useful lives range as follows:
|  |  |  | Office equipment | - | 4 | years
|  |  |  | Computer equipment | - | 3 | years
|  |  |  | Leasehold improvements | - | 4 | years
The assets' residual values, useful lives and depreciation methods are reviewed, and adjusted prospectively if appropriate, or if there is an indication of a significant change since the last reporting date. Gains and losses on disposals are determined by comparing the proceeds with the carrying amount and are recognised in profit or loss.
| 2.11 | Valuation of investments
Investments in subsidiaries are measured at cost less accumulated impairment.
| 2.12 | Cash at bank and in hand
Cash is represented by cash in hand and deposits with financial institutions repayable without penalty on notice of not more than 24 hours. Page 6
THIRTYFIVEBIO LIMITED NOTES TO THE FINANCIAL STATEMENTS FOR THE YEAR ENDED 31 DECEMBER 2024 2.Accounting policies (continued)
| 2.13 | Share capital
Ordinary shares are classified as equity. Incremental costs directly attributable to the issue of new ordinary shares or options are show in equity as a deduction, net of tax, from the proceeds.
| 2.14 | Financial instruments
The company has elected to apply Sections 11 and 12 of FRS 102 in respect of financial instruments. Financial assets and financial liabilities are recognised when the company becomes party to the contractual provisions of the instrument. Financial liabilities and equity instruments are classified according to the substance of the contractual arrangements entered into. An equity instrument is any contract that evidences a residual interest in the assets of the company after deducting all of its liabilities. The company’s policies for its major classes of financial assets and financial liabilities are set out below. Financial assets Basic financial assets, including other debtors and bank balances, are initially recognised at transaction price, unless the arrangement constitutes a financing transaction, where the transaction is measured at the present value of the future receipts discounted at a market rate of interest for a similar debt instrument. Financing transactions are those in which payment is deferred beyond normal business terms or is financed at a rate of interest that is not a market rate. Such assets are subsequently carried at amortised cost using the effective interest method, less any impairment. Financial liabilities Basic financial liabilities, including trade and other creditors, are initially recognised at transaction price, unless the arrangement constitutes a financing transaction, where the debt instrument is measured at the present value of the future payments discounted at a market rate of interest for a similar debt instrument. Financing transactions are those in which payment is deferred beyond normal business terms or is financed at a rate of interest that is not a market rate. Debt instruments are subsequently carried at amortised cost, using the effective interest rate method. Page 7
THIRTYFIVEBIO LIMITED NOTES TO THE FINANCIAL STATEMENTS FOR THE YEAR ENDED 31 DECEMBER 2024 2.Accounting policies (continued)
|  | Financial instruments (continued)
Impairment of financial assets Financial assets measured at cost and amortised cost are assessed at the end of each reporting period for objective evidence of impairment. If objective evidence of impairment is found, an impairment loss is recognised in the profit and loss account. For financial assets measured at cost less impairment, the impairment loss is measured as the difference between the asset's carrying amount and the best estimate of the amount the company would receive for the asset if it were to be sold at the reporting date. For financial assets measured at amortised cost, the impairment loss is measured as the difference between the asset's carrying amount and the present value of estimated cash flows discounted at the asset's original effective interest rate. If the financial asset has a variable interest rate, the discount rate for measuring any impairment loss is the current effective interest rate determined under the contract. If there is a decrease in the impairment loss arising from an event occurring after the impairment was recognised, the impairment is reversed. The reversal is such that the current carrying amount does not exceed what the carrying amount would have been had the impairment not previously been recognised. The impairment reversal is recognised in profit or loss. Derecognition of financial assets and financial liabilities Financial assets are derecognised when (a) the contractual rights to the cash flows from the asset expire or are settled, or (b) substantially all the risks and rewards of the ownership of the asset are transferred to another party or (c) despite having retained some significant risks and rewards of ownership, control of the asset has been transferred to another party who has the practical ability to unilaterally sell the asset to an unrelated third party without imposing additional restrictions. Financial liabilities are derecognised when the liability is extinguished, that is when the contractual obligation is discharged, cancelled or expires. Offsetting of financial assets and financial liabilities Financial assets and liabilities are offset and the net amount reported in the balance sheet when there is an enforceable right to set off the recognised amounts and there is an intention to settle on a net basis or to realise the asset and settle the liability simultaneously. Page 8
THIRTYFIVEBIO LIMITED NOTES TO THE FINANCIAL STATEMENTS FOR THE YEAR ENDED 31 DECEMBER 2024 2.Accounting policies (continued)
| 2.15 | Current and deferred taxation
The tax expense for the year comprises current and deferred tax. Tax is recognised in the profit and loss account, except that a charge attributable to an item of income and expense recognised as other comprehensive income or to an item recognised directly in equity is also recognised in other comprehensive income or directly in equity respectively. Current tax is the amount of income tax payable in respect of taxable profit for the year or prior years. The current income tax charge is calculated on the basis of tax rates and laws that have been enacted or substantively enacted by the balance sheet date in the countries where the company operates and generates income. Deferred tax arises from timing differences that are differences between taxable profits and total comprehensive income as stated in the financial statements. These timing differences arise from the inclusion of income and expenses in tax assessments in periods different from those in which they are recognised in the financial statements. Deferred tax balances are recognised in respect of all timing differences that have originated but not reversed by the balance sheet date, except that: ∙The recognition of deferred tax assets is limited to the extent that it is probable that they will be recovered against the reversal of deferred tax liabilities or other future taxable profits; and ∙Any deferred tax balances are reversed if and when all conditions for retaining associated tax allowances have been met. Deferred tax balances are not recognised in respect of permanent differences except in respect of business combinations, when deferred tax is recognised on the differences between the fair values of assets acquired and the future tax deductions available for them and the differences between the fair values of liabilities acquired and the amount that will be assessed for tax. Deferred tax is determined using tax rates and laws that have been enacted or substantively enacted by the balance sheet date.
3. | Employees
| The average monthly number of employees, including directors, during the year was 8 (2023 -6).
Page 9
THIRTYFIVEBIO LIMITED NOTES TO THE FINANCIAL STATEMENTS FOR THE YEAR ENDED 31 DECEMBER 2024
4. | Tangible fixed assets
|  | Office equipment | Computer equipment | Other fixed assets | Total
|  | £ | £ | £ | £
| Cost |  |  |  |
| At 1 January 2024 | 12,360 | 15,552 | 20,403 | 48,315
| At 31 December 2024 | 12,360 | 15,552 | 20,403 | 48,315
| Depreciation |  |  |  |
| At 1 January 2024 | 5,579 | 11,347 | 11,285 | 28,211
| Charge for the year | 3,091 | 3,426 | 5,100 | 11,617
| At 31 December 2024 | 8,670 | 14,773 | 16,385 | 39,828
| Net book value |  |  |  |
| At 31 December 2024 | 3,690 | 779 | 4,018 | 8,487
| At 31 December 2023 | 6,781 | 4,205 | 9,118 | 20,104
5. | Fixed asset investments
|  | Investments in subsidiary companies
|  | £
| Cost |
| At 1 January 2024 | 1
| At 31 December 2024 | 1
| The company holds 100% of the ordinary share capital in TFBio Limited, a subsidiary company which is registered in England and Wales.
Page 10
THIRTYFIVEBIO LIMITED NOTES TO THE FINANCIAL STATEMENTS FOR THE YEAR ENDED 31 DECEMBER 2024
6. | Debtors
|  |  |  |  | 2024 | 2023
|  |  |  |  | £ | £
| Other debtors | 529,953 | 778,486
| Prepayments and accrued income | 93,651 | 52,977
|  | 623,604 | 831,463
7. | Creditors: Amounts falling due within one year
|  |  |  |  | 2024 | 2023
|  |  |  |  | £ | £
| Other loans | 579,063 | -
| Trade creditors | 116,834 | 311,972
| Other taxation and social security | 34,508 | 64,095
| Other creditors | 2,508 | 3,662
| Accruals and deferred income | 263,926 | 28,838
|  | 996,839 | 408,567
| Included in other loans are convertible loan notes of $700,000 which will mature when certain conditions are met. Interest is charged at a rate of 8% per annum and is payable upon conversion.
Page 11
THIRTYFIVEBIO LIMITED NOTES TO THE FINANCIAL STATEMENTS FOR THE YEAR ENDED 31 DECEMBER 2024
8. | Share capital
|  |  |  |  | 2024 | 2023
|  |  |  |  | £ | £
|  | Allotted, called up and fully paid |  |
|  | 1,226,584 (2023 -1,218,416) Ordinary shares of £0.0001 each | 123 | 121
|  | 2,816,900 (2023 -2,816,900) Series A Preferred shares of £0.0001 each | 282 | 282
|  |  | 405 | 403
On 25 January 2024, 8,168 Ordinary £0.0001 shares were issued at par and fully paid up. The preferred shares have certain priority rights in respect of dividends or liquidation as noted in the Articles and Memorandum of Association. All other and preferred shares have equal voting rights. 9.Other financial commitments As at the balance sheet date, the company had commitments totalling £nil (2023: £1,502,133) relating to the uninvoiced cost of future research activities contractually agreed with the suppliers.
10. | Related party transactions
| Companies with a common director invoiced the company £711,891 (2023: £1,603,731) for services provided to the company and the company paid invoices from the companies with a common director totalling £842,947 (2023: £1,571,442). At the year end, the company owed companies with a common director amounts totalling £43,913 (2023: £174,969). The company has taken advantage of the exemption contained in FRS 102 section 33 "Related Party Disclosures" from disclosing transactions with entities which are a wholly owned part of the group.
11. | Post balance sheet events
On 27 February 2025, the company issued 41,022 Ordinary £0.0001 shares at par. On 16 July 2025 there was a designation of 3,347 £0.0001 Ordinary shares to 3,347 £0.0001 deferred shares. On the same day, the company purchased 3,347 £0.0001 deferred shares for cancellation.
Page 12