Diamant Thaçi: Investigator and/or consultant/advisor for AbbVie, Almirall, Amgen, BMS, Boehringer Ingelheim, Celltrion, Eli Lilly and Company, Galderma, Johnsson and Johnsson, Kyowa Kirin, LEO Pharma, L’Oréal, New Bridge, Novartis, Pfizer, Regeneron, Samsung, Sanofi, Takeda, Target-RWE, UCB and Vichy; received grants from AbbVie, LEO Pharma and Novartis. Akihiko Asahina: Honoraria and/or research grants from AbbVie, Amgen, BMS, Boehringer Ingelheim, Eisai, Eli Lilly and Company, Janssen, Kyowa Kirin, LEO Pharma, Maruho, Mitsubishi Tanabe Pharma, Novartis, Pfizer, Sun Pharma, Taiho Pharma, Torii Pharmaceutical Co. and UCB. Wolf-Henning Boehncke: Received honoraria as a speaker and/or advisor from AbbVie, Almirall, BMS, Eli Lilly and Company, Janssen, LEO Pharma, Novartis and UCB. Alice B. Gottlieb: At the time of manuscript preparation Alice B. Gottlieb was at Icahn School of Medicine at Mount Sinai, Alice B. Gottlieb’s affiliation is now Department of Dermatology, UT Southwestern Medical Center, Dallas, Texas, USA. Received research/educational grants from BMS, Janssen, MoonLake Immunotherapeutics and UCB (all paid to Mount Sinai School of Medicine until 1 May 2025). At UTSW Alice B. Gottlieb is Sub I on studies from BMS and Janssen; received honoraria/speaker fees as an advisory board member and consultant for Amgen, BMS, Eli Lilly and Company, Janssen, Novartis, Oruka, Sanofi, Sun Pharma, Takeda, Teva and UCB. Mark Lebwohl: Employee of Mount Sinai and receives research funds from Abbvie, Amgen, Arcutis, Avotres, Boehringer Ingelheim, Cara Therapeutics, Dermavant Sciences, Eli Lilly and Company, Incyte, Inozyme, Janssen Research & Development, LLC, Ortho Dermatologics, Pfizer, Sanofi-Regeneron and UCB; consultant for Almirall, AltruBio Inc., AnaptysBio, Apogee, Arcutis Inc., AstraZeneca, Atomwise, Avotres Therapeutics, BMS, Boehringer Ingelheim, Brickell Biotech, Castle Biosciences, Celltrion, CorEvitas, Dermavant Sciences, EPI, Evommune Inc., Facilitation of International Dermatology Education, Forte Biosciences, Foundation for Research and Education in Dermatology, Galderma, Genentech, Incyte, LEO Pharma, Meiji Seika Pharma, Mindera, Pfizer, Sanofi-Regeneron, Seanergy, Strata, Takeda, Trevi and Verrica. Mark Lebwohl is an Editorial Board member of Dermatology and Therapy. Mark Lebwohl was not involved in the selection of peer reviewers for the manuscript nor any of the subsequent editorial decisions. Richard B. Warren: Consulting fees from AbbVie, Almirall, Amgen, Arena, Astellas, Avillion, Biogen, BMS, Boehringer Ingelheim, Celgene, DICE Therapeutics, Eli Lilly and Company, GSK, Janssen, LEO Pharma, Meiji Pharma, Novartis, Pfizer, RAPT Therapeutics, Sanofi, Sun Pharma, UCB and Union; research grants to his institution from AbbVie, Almirall, Amgen, Celgene, Eli Lilly and Company, Janssen, LEO Pharma, Novartis, Pfizer and UCB; honoraria from AbbVie, Almirall, BMS, Eli Lilly and Company, Galderma, Janssen and Novartis. Richard B. Warren is an Editor-in-Chief of Dermatology and Therapy. Richard B. Warren was not involved in the selection of peer reviewers for the manuscript nor any of the subsequent editorial decisions. Heather Edens: Employee of UCB; shareholder of Abbott and UCB. Barbara Ink: Employee of UCB; shareholder of AbbVie, GSK and UCB. Rajan Bajracharya and Jason Coarse: Employees and shareholders of UCB. Joseph F. Merola: Consultant and/or investigator for AbbVie, Amgen, AstraZeneca, Biogen, BMS, Boehringer Ingelheim, Dermavant, Eli Lilly and Company, Incyte, Janssen, LEO Pharma, MoonLake Immunotherapeutics, Novartis, Pfizer, Sanofi-Regeneron, Sun Pharma and UCB.

The BE OPTIMAL and BE COMPLETE trials and their OLE study were conducted in accordance with the Declaration of Helsinki and the International Conference on Harmonisation Guidance for Good Clinical Practice. Ethics approval was obtained from the relevant institutional review boards at participating sites. Separate ethics approval for the current study was not obtained, as it was a post hoc analysis.

All participants provided written informed consent in accordance with local requirements, with additional written informed consent required for enrolment in the OLE study. All the results presented in this article are in aggregate form, and no personally identifiable information was used for this study.