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Registered number: 13157735












THIRTYFIVEBIO LIMITED
UNAUDITED FINANCIAL STATEMENTS
FOR THE YEAR ENDED 31 DECEMBER 2025

 

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 
Dr 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 2025

2025
2024
Note
£
£

Fixed assets
  

Tangible assets
 4 
864
8,487

Investments
 5 
1
1

  
865
8,488

Current assets
  

Debtors: amounts falling due within one year
 6 
759,088
623,604

Cash at bank and in hand
  
394,250
353,078

  
1,153,338
976,682

Creditors: amounts falling due within one year
 7 
(3,453,417)
(996,839)

Net current liabilities
  
 
 
(2,300,079)
 
 
(20,157)

Net liabilities
  
(2,299,214)
(11,669)


Capital and reserves
  

Called up share capital 
 8 
408
405

Share premium account
  
14,638,172
14,638,172

Capital redemption reserve
  
(2)
(2)

Profit and loss account
  
(16,937,792)
(14,650,244)

Net deficit
  
(2,299,214)
(11,669)


Page 2


 
REGISTERED NUMBER:13157735
THIRTYFIVEBIO LIMITED
    
BALANCE SHEET (CONTINUED)
AS AT 31 DECEMBER 2025

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: 




Dr J Westcott
Director

Date: 7 August 2026

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 2025

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 Financial Reporting Standard 102, the Financial Reporting Standard applicable in the UK and the Republic of Ireland and the Companies Act 2006. The disclosure requirements of Section 1A of FRS 102 have been applied other than where additional disclosure is required to show a true and fair view.

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 2026 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. 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 2025

2.Accounting policies (continued)

 
2.4

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.


2.5

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. 

Page 5

 

THIRTYFIVEBIO LIMITED

NOTES TO THE FINANCIAL STATEMENTS
FOR THE YEAR ENDED 31 DECEMBER 2025

2.Accounting policies (continued)





Financial instruments (continued)

Financial assets

Basic financial assets, including trade and other debtors, cash 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.

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.

Page 6

 

THIRTYFIVEBIO LIMITED

NOTES TO THE FINANCIAL STATEMENTS
FOR THE YEAR ENDED 31 DECEMBER 2025

2.Accounting policies (continued)





Financial instruments (continued)

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.

 
2.6

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.

  
2.7

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.

 
2.8

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.

 
2.9

Interest income

Interest income is recognised in profit or loss using the effective interest method.

 
2.10

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.

Page 7

 

THIRTYFIVEBIO LIMITED

NOTES TO THE FINANCIAL STATEMENTS
FOR THE YEAR ENDED 31 DECEMBER 2025

2.Accounting policies (continued)

 
2.11

Borrowing costs

All borrowing costs are recognised in profit or loss in the year in which they are incurred.

 
2.12

Valuation of investments

Investments in subsidiaries are measured at cost less accumulated impairment.

 
2.13

Foreign currency translation

Functional and presentation currency

The company's functional and presentational currency is Sterling (£).

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 are presented in profit or loss within 'administrative expenses'.

 
2.14

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.
Page 8

 

THIRTYFIVEBIO LIMITED

NOTES TO THE FINANCIAL STATEMENTS
FOR THE YEAR ENDED 31 DECEMBER 2025

2.Accounting policies (continued)



Current and deferred taxation (continued)


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.

  
2.15

Provisions for liabilities

Provisions are made where an event has taken place that gives the company a legal or constructive obligation that probably requires settlement by a transfer of economic benefit, and a reliable estimate can be made of the amount of the obligation.

Provisions are charged as an expense to profit or loss in the year that the company becomes aware of the obligation, and are measured at the best estimate at the balance sheet date of the expenditure required to settle the obligation, taking into account relevant risks and uncertainties.

When payments are eventually made, they are charged to the provision carried in the balance sheet.

  
2.16

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.


3.


Employees

The average monthly number of employees, including directors, during the year was 5 (2024 - 8).

Page 9

 

THIRTYFIVEBIO LIMITED

NOTES TO THE FINANCIAL STATEMENTS
FOR THE YEAR ENDED 31 DECEMBER 2025

4.


Tangible fixed assets


Office equipment
Computer equipment
Other fixed assets
Total

£
£
£
£



Cost


At 1 January 2025
12,360
15,552
20,403
48,315



At 31 December 2025

12,360
15,552
20,403
48,315



Depreciation


At 1 January 2025
8,670
14,773
16,385
39,828


Charge for the year
2,826
779
4,018
7,623



At 31 December 2025

11,496
15,552
20,403
47,451



Net book value



At 31 December 2025
864
-
-
864



At 31 December 2024
3,690
779
4,018
8,487


5.


Fixed asset investments





Investments in subsidiary companies

£



Cost


At 1 January 2025
1



At 31 December 2025
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 2025

6.


Debtors

2025
2024
£
£

Other debtors
449,466
529,953

Prepayments and accrued income
309,622
93,651

759,088
623,604



7.


Creditors: amounts falling due within one year

2025
2024
£
£

Other loans
2,951,661
579,063

Trade creditors
259,783
116,834

Other taxation and social security
28,360
34,508

Other creditors
4,918
2,508

Accruals
208,695
263,926

3,453,417
996,839


Included in other loans are convertible loan notes of $3,718,550 (2024: $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.

Following the year end, all outstanding convertible loan notes and related accrued interest were converted into equity. Further details are provided in Note 12.


8.


Share capital

2025
2024
£
£
Allotted, called up and fully paid



1,264,259 (2024 - 1,226,584) Ordinary shares of £0.00010 each
126
123
2,816,900 (2024 - 2,816,900) Series A Preferred shares of £0.00010 each
282
282

408

405


On 27 February 2025, 41,022 Ordinary £0.0001 shares were issued at par and fully paid up.

On 16 July 2025, the company redesignated 3,347 Ordinary shares of £0.0001 to 3,347 Deferred shares of £0.0001 each. On the same day, the company repurchased 3,347 Deferred shares which were immediately cancelled.

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.

Page 11

 

THIRTYFIVEBIO LIMITED

NOTES TO THE FINANCIAL STATEMENTS
FOR THE YEAR ENDED 31 DECEMBER 2025

9.


Pension commitments

The company operates a personal pension scheme for the benefits of its employees. The assets of the schemes are held separately from those of the company in independently administered funds. The pension cost charge represents contributions payable by the company to the funds and amounted to £32,522 (2024: £29,393). Contributions totalling £3,163 (2024: £2,161) were payable to the funds at the balance sheet date.


10.Other financial commitments

As at the balance sheet date, the company had commitments totalling £101,726 (2024: £nil) relating to the uninvoiced cost of future research activities contractually agreed with the suppliers.


11.


Related party transactions

Companies with a common director invoiced the company £1,362,150 (2024: £711,891) for services provided to the company. At the year end, the company owed companies with a common director amount totalling £179,045 (2024: £43,913).

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.


12.


Post balance sheet events

On 20 January 2026, the company redesignated 68 Ordinary shares of £0.0001 each to 68 Deferred shares of £0.0001 each. On the same day, the company repurchased 68 Deferred shares which were immediately cancelled.

On 29 April 2026, the company redesignated 2,816,900 Series A Preferred shares of £0.0001 each to Seed-1 Preferred shares of £0.0001 each.

On 1 May 2026, the company completed the conversion of all outstanding convertible loan notes and related accrued interest into equity.

As part of the transaction, a holder of convertible loan notes, converted its outstanding convertible loan notes and accrued interest and subscribed for 280,985 Seed-1 Preferred shares at a price per share of $7.10, representing consideration of $1,994,994.

Additionally, all remaining holders of convertible loan notes converted their outstanding principal and accrued interest into equity. This resulted in the issue of 409,289 Seed-2 Preferred shares at a subscription price of $5.68 per share, representing the conversion of $2,324,762 of principal and accrued interest.

Following completion of these transactions, all outstanding convertible loan note liabilities were extinguished and replaced by equity instruments. As a result, the company no longer had any outstanding convertible loan note obligations as at the date of approval of these financial statements.

 
Page 12