v3.26.1
Financial liabilities - Disclosure of Maturity Analysis for Advances Loans and Lease Liabilities (Details)
€ in Thousands
 12 Months Ended
Jul. 10, 2020
Dec. 31, 2024
EUR (€)
subsidiary
Dec. 31, 2025
EUR (€)
Summary of Maturity Analysis for Advances Loans and Lease Liabilities [Line Items]      
Total   € 111,036 € 344,089
Borrowing, number of PGE | subsidiary   2  
Borrowing, maturity   5 years  
Borrowing, deferment period   1 year  
Less than 1 year      
Summary of Maturity Analysis for Advances Loans and Lease Liabilities [Line Items]      
Total   € 5,210 4,508
Between 1 and 3 years      
Summary of Maturity Analysis for Advances Loans and Lease Liabilities [Line Items]      
Total   24,689 145,037
Between 3 and 5 years      
Summary of Maturity Analysis for Advances Loans and Lease Liabilities [Line Items]      
Total   41,725 72,637
More than 5 years      
Summary of Maturity Analysis for Advances Loans and Lease Liabilities [Line Items]      
Total   39,412 161,949
Bpifrance      
Summary of Maturity Analysis for Advances Loans and Lease Liabilities [Line Items]      
Borrowings   1,637 716
Bpifrance | Less than 1 year      
Summary of Maturity Analysis for Advances Loans and Lease Liabilities [Line Items]      
Borrowings   800 716
Bpifrance | Between 1 and 3 years      
Summary of Maturity Analysis for Advances Loans and Lease Liabilities [Line Items]      
Borrowings   837 0
Bpifrance | Between 3 and 5 years      
Summary of Maturity Analysis for Advances Loans and Lease Liabilities [Line Items]      
Borrowings   0 0
Bpifrance | More than 5 years      
Summary of Maturity Analysis for Advances Loans and Lease Liabilities [Line Items]      
Borrowings   0 0
Interest-free Bpifrance loan      
Summary of Maturity Analysis for Advances Loans and Lease Liabilities [Line Items]      
Borrowings   0  
Interest-free Bpifrance loan | Less than 1 year      
Summary of Maturity Analysis for Advances Loans and Lease Liabilities [Line Items]      
Borrowings   0  
Interest-free Bpifrance loan | Between 1 and 3 years      
Summary of Maturity Analysis for Advances Loans and Lease Liabilities [Line Items]      
Borrowings   0  
Interest-free Bpifrance loan | Between 3 and 5 years      
Summary of Maturity Analysis for Advances Loans and Lease Liabilities [Line Items]      
Borrowings   0  
Interest-free Bpifrance loan | More than 5 years      
Summary of Maturity Analysis for Advances Loans and Lease Liabilities [Line Items]      
Borrowings   0  
Curadigm interest-free Bpifrance advance      
Summary of Maturity Analysis for Advances Loans and Lease Liabilities [Line Items]      
Borrowings   375 250
Curadigm interest-free Bpifrance advance | Less than 1 year      
Summary of Maturity Analysis for Advances Loans and Lease Liabilities [Line Items]      
Borrowings   100 100
Curadigm interest-free Bpifrance advance | Between 1 and 3 years      
Summary of Maturity Analysis for Advances Loans and Lease Liabilities [Line Items]      
Borrowings   200 150
Curadigm interest-free Bpifrance advance | Between 3 and 5 years      
Summary of Maturity Analysis for Advances Loans and Lease Liabilities [Line Items]      
Borrowings   75 0
Curadigm interest-free Bpifrance advance | More than 5 years      
Summary of Maturity Analysis for Advances Loans and Lease Liabilities [Line Items]      
Borrowings   0 0
HSBC "PGE"      
Summary of Maturity Analysis for Advances Loans and Lease Liabilities [Line Items]      
Borrowings   1,903 631
HSBC "PGE" | Less than 1 year      
Summary of Maturity Analysis for Advances Loans and Lease Liabilities [Line Items]      
Borrowings   1,272 631
HSBC "PGE" | Between 1 and 3 years      
Summary of Maturity Analysis for Advances Loans and Lease Liabilities [Line Items]      
Borrowings   631 0
HSBC "PGE" | Between 3 and 5 years      
Summary of Maturity Analysis for Advances Loans and Lease Liabilities [Line Items]      
Borrowings   0 0
HSBC "PGE" | More than 5 years      
Summary of Maturity Analysis for Advances Loans and Lease Liabilities [Line Items]      
Borrowings   0 0
Bpifrance "PGE"      
Summary of Maturity Analysis for Advances Loans and Lease Liabilities [Line Items]      
Borrowings   2,237 948
Borrowing, maturity 6 years    
Bpifrance "PGE" | Less than 1 year      
Summary of Maturity Analysis for Advances Loans and Lease Liabilities [Line Items]      
Borrowings   1,289 948
Bpifrance "PGE" | Between 1 and 3 years      
Summary of Maturity Analysis for Advances Loans and Lease Liabilities [Line Items]      
Borrowings   948 0
Bpifrance "PGE" | Between 3 and 5 years      
Summary of Maturity Analysis for Advances Loans and Lease Liabilities [Line Items]      
Borrowings   0 0
Bpifrance "PGE" | More than 5 years      
Summary of Maturity Analysis for Advances Loans and Lease Liabilities [Line Items]      
Borrowings   0 0
EIB Loan      
Summary of Maturity Analysis for Advances Loans and Lease Liabilities [Line Items]      
Borrowings   100,389 109,492
EIB Loan | Less than 1 year      
Summary of Maturity Analysis for Advances Loans and Lease Liabilities [Line Items]      
Borrowings   467 824
EIB Loan | Between 1 and 3 years      
Summary of Maturity Analysis for Advances Loans and Lease Liabilities [Line Items]      
Borrowings   19,942 19,099
EIB Loan | Between 3 and 5 years      
Summary of Maturity Analysis for Advances Loans and Lease Liabilities [Line Items]      
Borrowings   40,784 46,421
EIB Loan | More than 5 years      
Summary of Maturity Analysis for Advances Loans and Lease Liabilities [Line Items]      
Borrowings   39,196 43,149
HCR Royalty Financing      
Summary of Maturity Analysis for Advances Loans and Lease Liabilities [Line Items]      
Borrowings     228,809
HCR Royalty Financing | Less than 1 year      
Summary of Maturity Analysis for Advances Loans and Lease Liabilities [Line Items]      
Borrowings     0
HCR Royalty Financing | Between 1 and 3 years      
Summary of Maturity Analysis for Advances Loans and Lease Liabilities [Line Items]      
Borrowings     105,949
HCR Royalty Financing | Between 3 and 5 years      
Summary of Maturity Analysis for Advances Loans and Lease Liabilities [Line Items]      
Borrowings     21,754
HCR Royalty Financing | More than 5 years      
Summary of Maturity Analysis for Advances Loans and Lease Liabilities [Line Items]      
Borrowings     101,106
Lease liabilities      
Summary of Maturity Analysis for Advances Loans and Lease Liabilities [Line Items]      
Lease liabilities   4,495 3,243
Lease liabilities | Less than 1 year      
Summary of Maturity Analysis for Advances Loans and Lease Liabilities [Line Items]      
Lease liabilities   1,282 1,289
Lease liabilities | Between 1 and 3 years      
Summary of Maturity Analysis for Advances Loans and Lease Liabilities [Line Items]      
Lease liabilities   2,131 1,299
Lease liabilities | Between 3 and 5 years      
Summary of Maturity Analysis for Advances Loans and Lease Liabilities [Line Items]      
Lease liabilities   866 656
Lease liabilities | More than 5 years      
Summary of Maturity Analysis for Advances Loans and Lease Liabilities [Line Items]      
Lease liabilities   € 216 € 0