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v3.24.3

Nature of the business and basis of presentation - Liquidity (Details) $ / shares in Units, $ in Thousands |  |  |  | 3 Months Ended | 9 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | ---
May 28, 2024 USD ($) | May 23, 2024 £ / shares shares | Jul. 17, 2023 USD ($) shares | Sep. 30, 2024 USD ($) shares | Jun. 30, 2024 USD ($) | Mar. 31, 2024 USD ($) | Sep. 30, 2023 USD ($) shares | Jun. 30, 2023 USD ($) | Mar. 31, 2023 USD ($) | Sep. 30, 2024 USD ($) shares | Sep. 30, 2023 USD ($) shares | Sep. 30, 2024 £ / shares | May 23, 2024 $ / shares | Dec. 31, 2023 USD ($) | Dec. 31, 2023 £ / shares | Jul. 17, 2023 £ / shares | Jul. 17, 2023 $ / shares
Cash and cash equivalents |  |  |  | $ 890,862 |  |  | $ 572,086 |  |  | $ 890,862 | $ 572,086 |  |  | $ 526,423 |  |  |
Ordinary shares, nominal value | £ / shares |  |  |  |  |  |  |  |  |  |  |  | £ 0.01 |  |  | £ 0.01 |  |
Gross proceeds before discounts and commissions |  |  |  |  | $ 544,127 |  | 234,492 | $ 12,127 | $ 2,716 |  |  |  |  |  |  |  |
Proceeds from the issuance, net of issuance costs |  |  |  |  |  |  |  |  |  | 544,127 | 249,335 |  |  |  |  |  |
Net Income (Loss) |  |  |  | (50,802) | $ (39,812) | $ (26,563) | $ (49,898) | $ (42,603) | $ (39,064) | (117,177) | $ (131,565) |  |  |  |  |  |
Accumulated deficit |  |  |  | $ (628,937) |  |  |  |  |  | $ (628,937) |  |  |  | $ (511,760) |  |  |
At the market offering | American Depositary Shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Shares issued (in shares) | shares |  |  |  | 0 |  |  | 941,176 |  |  | 0 | 1,561,176 |  |  |  |  |  |
Gross proceeds before discounts and commissions |  |  |  |  |  |  | $ 20,000 |  |  |  | $ 35,300 |  |  |  |  |  |
Proceeds from the issuance, net of issuance costs |  |  |  |  |  |  | 19,400 |  |  |  | 34,200 |  |  |  |  |  |
Commissions and offering expenses |  |  |  |  |  |  | $ 600 |  |  |  | $ 1,100 |  |  |  |  |  |
Purchase Agreement |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Gross proceeds before discounts and commissions | $ 555,500 |  | $ 230,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proceeds from the issuance, net of issuance costs | 544,100 |  | 215,100 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Commissions and offering expenses | $ 11,400 |  | $ 14,900 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Purchase Agreement | American Depositary Shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Shares issued (in shares) | shares |  | 6,764,705 | 6,117,648 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Ordinary shares, nominal value | £ / shares |  | £ 0.01 |  |  |  |  |  |  |  |  |  |  |  |  |  | £ 0.01 |
Share issue price | $ / shares |  |  |  |  |  |  |  |  |  |  |  |  | $ 21.42 |  |  |  | $ 21.25
Purchase Agreement | Non voting ordinary shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Shares issued (in shares) | shares |  | 19,169,001 | 4,705,882 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Ordinary shares, nominal value | £ / shares |  | £ 0.01 |  |  |  |  |  |  |  |  |  |  |  |  |  | £ 0.01 |
Purchase Agreement | Underwritten Public Offering | American Depositary Shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Shares issued (in shares) | shares |  |  | 1,411,764 |  |  |  |  |  |  |  |  |  |  |  |  |  |

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