The interest rate on borrowings. [Refer: Borrowings]

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The amount of costs associated with financing activities of the entity.

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The amount of assets that are: (a) cash; (b) an equity instrument of another entity; (c) a contractual right: (i) to receive cash or another financial asset from another entity; or (ii) to exchange financial assets or financial liabilities with another entity under conditions that are potentially favourable to the entity; or (d) a contract that will, or may be, settled in the entity’s own equity instruments and is: (i) a non-derivative for which the entity is, or may be, obliged to receive a variable number of the entity’s own equity instruments; or (ii) a derivative that will, or may be, settled other than by the exchange of a fixed amount of cash or another financial asset for a fixed number of the entity’s own equity instruments. For this purpose the entity’s own equity instruments do not include puttable financial instruments classified as equity instruments in accordance with paragraphs 16A-16B of IAS 32, instruments that impose on the entity an obligation to deliver to another party a pro rata share of the net assets of the entity only on liquidation and are classified as equity instruments in accordance with paragraphs 16C-16D of IAS 32, or instruments that are contracts for the future receipt or delivery of the entity’s own equity instruments. [Refer: Financial instruments, class [member]; Financial liabilities]

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The amount of liabilities that are: (a) a contractual obligation: (i) to deliver cash or another financial asset to another entity; or (ii) to exchange financial assets or financial liabilities with another entity under conditions that are potentially unfavourable to the entity; or (b) a contract that will, or may be, settled in the entity’s own equity instruments and is: (i) a non-derivative for which the entity is, or may be, obliged to deliver a variable number of the entity’s own equity instruments; or (ii) a derivative that will, or may be, settled other than by the exchange of a fixed amount of cash or another financial asset for a fixed number of the entity’s own equity instruments. For this purpose, rights, options or warrants to acquire a fixed number of the entity’s own equity instruments for a fixed amount of any currency are equity instruments if the entity offers the rights, options or warrants pro rata to all of its existing owners of the same class of its own non-derivative equity instruments. Also, for those purposes the entity’s own equity instruments do not include puttable financial instruments that are classified as equity instruments in accordance with paragraphs 16A-16B of IAS 32, instruments that impose on the entity an obligation to deliver to another party a pro rata share of the net assets of the entity only on liquidation and are classified as equity instruments in accordance with paragraphs 16C-16D of IAS 32, or instruments that are contracts for the future receipt or delivery of the entity’s own equity instruments. As an exception, an instrument that meets the definition of a financial liability is classified as an equity instrument if it has all the features and meets the conditions in paragraphs 16A-16B or paragraphs 16C-16D of IAS 32. [Refer: Financial instruments, class [member]; Financial assets; Derivatives [member]]

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- Definition

The amount of interest income on deposits. [Refer: Interest income]

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The amount of loans received.

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The interest rate of borrowings for first twelve months.

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No definition available.

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Maximum borrowing capacity under loan agreement.

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No definition available.

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Financial instruments, Interest risk (Details)	12 Months Ended
Financial instruments, Interest risk (Details)	Dec. 31, 2020 GBP (£)	Dec. 31, 2019 GBP (£)	Dec. 31, 2018 GBP (£)	Dec. 31, 2019 USD ($)	Sep. 13, 2017 USD ($)
Interest risk [Abstract]
Increase (decrease) net annual interest income	£ 0	£ 0	£ 272,000
Finance cost	£ 3,375,000	£ 9,379,000	£ 842,000
Oxford Finance Agreement [Member] \| LIBOR [Member]
Interest risk [Abstract]
Borrowings, interest rate	8.85%
Oxford Finance Agreement [Member] \| LIBOR [Member] \| Bottom of Range [Member]
Interest risk [Abstract]
Borrowings, interest rate	9.01%
Oxford Finance Agreement [Member] \| LIBOR [Member] \| Top of Range [Member]
Interest risk [Abstract]
Borrowings, interest rate	12.01%
Gates Foundation Convertible Loan [Member]
Interest risk [Abstract]
Maximum borrowing capacity \| $				$ 40,000,000	$ 40,000,000
Loans received \| $					25,000,000
Borrowings interest rate for first twelve months	2.00%
Gates Foundation Convertible Loan [Member] \| First Tranche [Member]
Interest risk [Abstract]
Loans received \| $					$ 25,000,000
Borrowings interest rate for first twelve months		2.00%		2.00%
Interest Rate Risk [Member]
Disclosure of financial assets [abstract]
Financial assets	£ 129,716,000	£ 73,966,000
Disclosure of financial liabilities [abstract]
Financial liabilities	36,654,000	19,157,000
Interest Rate Risk [Member] \| Interest Bearing Loans and Borrowings [Member]
Disclosure of financial liabilities [abstract]
Financial liabilities	36,654,000	19,157,000
Interest Rate Risk [Member] \| Cash and Cash Equivalents [Member]
Disclosure of financial assets [abstract]
Financial assets	129,716,000	73,966,000
Bank of England Base Rate + 0.5% Percentage Points [Member]
Interest risk [Abstract]
Increase (decrease) net annual interest income	649,000	370,000
Bank of England Base Rate - 0.5% Percentage Points [Member]
Interest risk [Abstract]
Increase (decrease) net annual interest income	(649,000)	(370,000)
LIBOR Base Rate +0.5% Percentage Points [Member] \| Oxford Finance Agreement [Member]
Interest risk [Abstract]
Finance cost	183,000	0
LIBOR Base Rate - 0.5% Percentage Points [Member] \| Oxford Finance Agreement [Member]
Interest risk [Abstract]
Finance cost	£ (183,000)	£ 0