Accounts receivables - Summary of Trade receivables (Detail) - EUR (€) € in Thousands	Dec. 31, 2025	Dec. 31, 2024
Trade and other current receivables [abstract]
Receivables From Collaboration Agreements	€ 6,099	€ 5,857
Total	€ 6,099	€ 5,857

The amount of current trade receivables. [Refer: Trade receivables]

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