Significant Events and Transactions	9 Months Ended
Sep. 30, 2026
Significant Events And Transactions [Abstract]
Significant Events and Transactions	Significant Events and Transactions Amendment to the Letter of intent signed with Fareva Amboise On September 30, 2026, the Company entered into Amendment No. 1 to its June 25, 2026 Letter of Intent with Fareva Amboise concerning manufacturing readiness activities supporting the future commercial-scale manufacture of the VIASKIN Peanut patch. The planned investment is estimated at $5.5 million (at the exchange rate of 1€ = $1.14). Under the amendment, the Company's $1.1 million (at the exchange rate of 1€ = $1.14) upfront contribution to this project was modified such that payment is no longer contingent upon FDA approval of the Company's Biologics License Application. Instead, payment is contingent upon the successful completion of an independent Mock Pre-Approval Inspection, including the absence of critical findings or repeat observations and remediation of all findings by February 1, 2027. In addition, the amendment finalized and secured the workforce expansion component of the project, including training and extended readiness activities. These personnel are dedicated to supporting industrial ramp-up, execution of the remediation plan and commercial manufacturing preparedness. The parties continue to negotiate a definitive commercial manufacturing and supply agreement. The Company expects the amended arrangement to support the timely execution of manufacturing readiness activities and further prepares the Amboise facility for future commercial production of VIASKIN® Peanut, if approved, including activities necessary to support a successful FDA pre-approval inspection. Submission of BLA FDA for the VIASKIN® Peanut Patch in Children Aged 4-7 Years On September 29, 2026, the Company announced the submission of a BLA to FDA seeking approval of the VIASKIN® Peanut patch for the treatment of peanut allergy in children aged 4 through 7 years. The submission is supported by data from the Phase 3 VITESSE study, a randomized, double-blind, placebo-controlled trial, which enrolled 654 children. The Company has requested Priority Review designation, which, if granted, would reduce the standard review period from ten to six months. The FDA has 60 days from the submission date to determine whether the BLA is sufficiently complete to permit substantive review, following which the Company anticipates receipt of a Prescription Drug User Fee Act (“PDUFA”) target action date. The BLA filing represents a significant regulatory milestone and an important step toward the potential commercialization of VIASKIN Peanut patch in the United States. There can be no assurance that the FDA will accept the BLA for filing, grant Priority Review, or ultimately approve the VIASKIN Peanut patch. In connection with the BLA submission, $4.7 million of previously deferred BLA-related costs were recognized as research and development expense during the quarter. Shelf Registration Statement, ATM Program Refresh and Sale of $50 million in gross proceeds under ATM Program On July 27, 2026, the Company filed an automatically effective shelf registration statement on Form S-3 ASR with the SEC. The shelf registration statement permits the Company to sell, from time to time, ordinary shares, American Depositary Shares (“ADSs”) representing ordinary shares and warrants. At the time of filing the shelf registration statement, the Company also filed a prospectus supplement with the SEC authorizing the sale of up to $150.0 million of ADSs under its existing at-the-market offering program (the "ATM Program") and shelf registration statement. On August 3, 2026, the Company announced the sale of $50.0 million in gross proceeds of ADSs to RA Capital Management, L.P. under the ATM Program. In connection with this transaction, the Company issued 18,288,220 new ordinary shares, underlying 3,657,644 new ADSs, at an at-the-market price of $13.67 per ADS. The net proceeds from the offering were recorded as an increase to shareholders' equity, net of issuance costs, in the condensed consolidated statements of financial position. Services Agreement with Fareva La Vallée - Peanut Drug Substance On July 8, 2026, the Company entered into a PDS Services Agreement and Binding Commercial Term Sheet with FLV relating to the construction development, installation and qualification of a dedicated PDS manufacturing line, as well as related transfer services for technical and validation batches. Letter of intent signed with Integrated Commercialization Solutions On June 5, 2026, the Company entered into a Letter of Intent with Integrated Commercialization Solutions, LLC ("ICS") in connection with future commercialization support and distribution services for the VIASKIN Peanut patch in the United States, if approved. Under the letter of intent, the parties agreed to undertake certain preliminary launch readiness and implementation planning activities while continuing negotiations toward a definitive commercial outsourcing services agreement. The contemplated activities include operational planning, systems readiness, distribution infrastructure preparation and other commercialization support services intended to facilitate a potential future product launch, if approved. As of September 30, 2026, negotiations of the definitive agreement remained ongoing and no material amounts had been incurred by the Company under the letter of intent. Management expects execution of the definitive agreement by the end of 2026. Accordingly, the arrangement has no material impact on the Company's condensed consolidated financial statements as of September 30, 2026. Manufacturing Supply Agreement (Peanut Source Material) with Fareva La Vallée On March 17, 2026, the Company entered into the MS Agreement with FLV, under which FLV will manufacture and supply the PSM exclusively for DBV Technologies S.A. during the agreement term. The term is effective for a period of eight (8) years and can be renewed for a period of two (2) years. March 2025 PIPE Financing On January 16, 2026, the Company received the supplemental gross proceeds of $94.7 million (€81.0 million) resulting in the full exercise of the warrants to purchase 34,090,004 new shares at a par value of €0.10 (the “ABSA Warrants”) and of the warrants to subscribe for 1.75 shares of the Company (the “BS Warrants”) issued in the March 2025 PIPE Financing. Administrative Proceedings During the second quarter of 2026, the Company received notice from the French tax authorities of a routine, not-for-cause tax audit covering fiscal years 2022 through 2025. During the third quarter of 2026, the Company addressed and resolved all matters raised to date by the tax authorities. The audit remains ongoing, and the Company continues to cooperate fully with the Tax administration.

manufacturing readiness activities supporting the future commercial-scale manufacture of the VIASKIN Peanut patch. The planned investment is estimated at $5.5 million (at the exchange rate of 1€ = $1.14). Under the amendment, the Company's $1.1 million (at the exchange rate of 1€ = $1.14) upfront contribution to this project was modified such that payment is no longer contingent upon FDA approval of the Company's Biologics License Application. Instead, payment is contingent upon the successful completion of an independent Mock Pre-Approval Inspection, including the absence of critical findings or repeat observations and remediation of all findings by February 1, 2027.

In addition, the amendment finalized and secured the workforce expansion component of the project, including training and extended readiness activities. These personnel are dedicated to supporting industrial ramp-up, execution of the remediation plan and commercial manufacturing preparedness. The parties continue to negotiate a definitive commercial manufacturing and supply agreement. The Company expects the amended arrangement to support the timely execution of manufacturing readiness activities and further prepares the Amboise facility for future commercial production of VIASKIN® Peanut, if approved, including activities necessary to support a successful FDA pre-approval inspection.

Submission of BLA FDA for the VIASKIN® Peanut Patch in Children Aged 4-7 Years
On September 29, 2026, the Company announced the submission of a BLA to FDA seeking approval of the VIASKIN® Peanut patch for the treatment of peanut allergy in children aged 4 through 7 years. The submission is supported by data from the Phase 3 VITESSE study, a randomized, double-blind, placebo-controlled trial, which enrolled 654 children. The Company has requested Priority Review designation, which, if granted, would reduce the standard review period from ten to six months. The FDA has 60 days from the submission date to determine whether the BLA is sufficiently complete to permit substantive review, following which the Company anticipates receipt of a Prescription Drug User Fee Act (“PDUFA”) target action date. The BLA filing represents a significant regulatory milestone and an important step toward the potential commercialization of VIASKIN Peanut patch in the United States. There can be no assurance that the FDA will accept the BLA for filing, grant Priority Review, or ultimately approve the VIASKIN Peanut patch.

Shelf Registration Statement, ATM Program Refresh and Sale of $50 million in gross proceeds under ATM Program
On July 27, 2026, the Company filed an automatically effective shelf registration statement on Form S-3 ASR with the SEC. The shelf registration statement permits the Company to sell, from time to time, ordinary shares, American Depositary Shares (“ADSs”) representing ordinary shares and warrants. At the time of filing the shelf registration statement, the Company also filed a prospectus supplement with the SEC authorizing the sale of up to $150.0 million of ADSs under its existing at-the-market offering program (the "ATM Program") and shelf registration statement. On August 3, 2026, the Company announced the sale of $50.0 million in gross proceeds of ADSs to RA Capital Management, L.P. under the ATM Program. In connection with this transaction, the Company issued 18,288,220 new ordinary shares, underlying 3,657,644 new ADSs, at an at-the-market price of $13.67 per ADS.

Services Agreement with Fareva La Vallée - Peanut Drug Substance
On July 8, 2026, the Company entered into a PDS Services Agreement and Binding Commercial Term Sheet with FLV relating to the construction development, installation and qualification of a dedicated PDS manufacturing line, as well as related transfer services for technical and validation batches.

Letter of intent signed with Integrated Commercialization Solutions
On June 5, 2026, the Company entered into a Letter of Intent with Integrated Commercialization Solutions, LLC ("ICS") in connection with future commercialization support and distribution services for the VIASKIN Peanut patch in the United States, if approved. Under the letter of intent, the parties agreed to undertake certain preliminary launch readiness and implementation planning activities while continuing negotiations toward a definitive commercial outsourcing services agreement. The contemplated activities include operational planning, systems readiness, distribution infrastructure preparation and other commercialization support services intended to facilitate a potential future product launch, if approved.

As of September 30, 2026, negotiations of the definitive agreement remained ongoing and no material amounts had been incurred by the Company under the letter of intent. Management expects execution of the definitive agreement by the end of 2026. Accordingly, the arrangement has no material impact on the Company's condensed consolidated financial statements as of September 30, 2026.

Manufacturing Supply Agreement (Peanut Source Material) with Fareva La Vallée
On March 17, 2026, the Company entered into the MS Agreement with FLV, under which FLV will manufacture and supply the PSM exclusively for DBV Technologies S.A. during the agreement term. The term is effective for a period of eight (8) years and can be renewed for a period of two (2) years.

March 2025 PIPE Financing
On January 16, 2026, the Company received the supplemental gross proceeds of $94.7 million (€81.0 million) resulting in the full exercise of the warrants to purchase 34,090,004 new shares at a par value of €0.10 (the “ABSA Warrants”) and of the warrants to subscribe for 1.75 shares of the Company (the “BS Warrants”) issued in the March 2025 PIPE Financing.

During the second quarter of 2026, the Company received notice from the French tax authorities of a routine, not-for-cause tax audit covering fiscal years 2022 through 2025. During the third quarter of 2026, the Company addressed and resolved all matters raised to date by the tax authorities. The audit remains ongoing, and the Company continues to cooperate fully with the Tax administration.