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(11)

EP 4 816 596 A1

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(43) Date of publication: 07.10.2026 Bulletin 2026/41 (21) Application number: 24824669.6 (22) Date of filing: 28.11.2024

(51) International Patent Classification (IPC):  C25B 3/05(2021.01) C25B 3/23(2021.01) C25B 3/07(2021.01) C25B 11/042(2021.01) (52) Cooperative Patent Classification (CPC): C25B 3/05; C25B 3/07; C25B 3/23; C25B 11/042 (86) International application number: PCT/US2024/057928 (87) International publication number: WO 2025/117870 (05.06.2025 Gazette 2025/23)

(84) Designated Contracting States: AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC ME MK MT NL NO PL PT RO RS SE SI SK SM TR Designated Extension States: BA Designated Validation States: GE KH MA MD TN (30) Priority: 01.12.2023 JP 2023204269 (71) Applicant: PTC THERAPEUTICS, INC. Warren, NJ 07059 (US)	(72) Inventors: USUTANI, Hirotsugu Osaka 554-0022 (JP) HIRABAYASHI, Jun Osaka 541-0045 (JP) (74) Representative: J A Kemp LLP  80 Turnmill Street London EC1M 5QU London EC1M 5QU (GB)