Conflicts of interest Dr Alexander Egeberg has received research funding from Pfizer, Eli Lilly, Novartis, Boehringer-Ingelheim, Bristol-Myers Squibb, AbbVie, Janssen Pharmaceuticals, the Danish National Psoriasis Foundation, the Simon Spies Foundation, and the Kgl Hofbundtmager Aage Bang Foundation, and has received honoraria as consultant and/or speaker from AbbVie, Almirall, Boehringer-Ingelheim, LEO Pharma, Zuellig Pharma Ltd, Galápagos NV, Sun Pharma, Samsung Bioepis, Pfizer, Eli Lilly, Novartis, Galderma, Dermavant, UCB, Mylan, Bristol-Myers Squibb, and Janssen. Dr Hans C. Ring has conducted advisory board work for Novartis and has received honoraria as speaker from LEO Pharma and research funding from the Kgl Hofbundtmager Aage Bang Foundation. Dr John W. Frew has conducted advisory work for Janssen, Boehringer-Ingelheim, Pfizer, Kyowa Kirin, LEO Pharma, Regeneron, Chemocentryx, AbbVie, Azora, Novartis, and UCB, participated in trials for Pfizer, UCB, Boehringer-Ingelheim, Eli Lilly, CSL, and Azora, and received research support from Ortho Dermatologics, Sun Pharma, LEO Pharma, UCB, and La Roche Posay. Drs James P. Pham, Nana A.L. Rosenø, Gabriele Roccuzzo, and Ryan C. Saal have no conflicts of interest to disclose.