Funding

Open Access funding enabled and organized by Projekt DEAL. The ECZTRA 1 and 2 clinical trials were sponsored by LEO Pharma A/S (Ballerup, Denmark).

Conflicts of Interest/Competing interests

Eric L. Simpson reports personal fees from AbbVie, Amgen, Arena Pharmaceuticals, Aslan Pharma, Benevolent AI Bio Limited “BAI”, BiomX Ltd, Bluefin Biomedicine Inc, Boehringer-Ingelheim, Boston Consulting Group, Collective Acumen, LLC (CA), Coronado, Dermira, Eli Lilly, Evidera, ExcerptaMedica, Galderma, GlaxoSmithKline, Forte Bio RX, Incyte Dermatologics, Janssen, Kyowa Kirin Pharmaceutical Development, Leo Pharm, Medscape LLC, Merck, Novartis, Ortho Galderma, Pfizer, Physicians World LLC, Pierre Fabre Dermo Cosmetique, Regeneron, Roivant, Sanofi- Genzyme, SPARC India, Trevi therapeutics, WebMD, and Valeant; reports grants (or served as the Principal Investigator) from AbbVie, Amgen, Arcutis, Aslan, Castle Biosciences, Inc Celegene, CorEvitas, Dermavant, Dermira, Eli Lilly, Galderma, Incyte, Kymab, Kyowa Hakko Kirin, Leo Pharmaceuticals, Merck, Novartis, Pfizer, Regeneron, Sanofi, and TARGET-DERM. Andrew Blauvelt has served as a speaker (received honoraria) for AbbVie, Bristol-Myers Squibb, Eli Lilly and Company, Pfizer, Regeneron, and Sanofi, served as a scientific adviser (received honoraria) for AbbVie, Abcentra, Aclaris, Affibody, Aligos, Almirall, Alumis, Amgen, Anaptysbio, Arcutis, Arena, Aslan, Athenex, Bluefin Biomedicine, Boehringer Ingelheim, Bristol-Myers Squibb, Cara Therapeutics, Dermavant, EcoR1, Eli Lilly and Company, Escient, Evelo, Evommune, Forte, Galderma, HighlightII Pharma, Incyte, InnoventBio, Janssen, Landos, LEO Pharma, Merck, Novartis, Pfizer, Rani, Rapt, Regeneron, Sanofi Genzyme, Spherix Global Insights, Sun Pharma, TLL Pharmaceutical, TrialSpark, UCB Pharma, Union, Vibliome, and Xencor, and has acted as a clinical study investigator (institution has received clinical study funds) for AbbVie, Acelyrin, Allakos, Almirall, Alumis, Amgen, Arcutis, Athenex, Boehringer Ingelheim, Bristol-Myers Squibb, Concert, Dermavant, Eli Lilly and Company, Evelo, Evommune, Galderma, Incyte, Janssen, LEO Pharma, Merck, Novartis, Pfizer, Regeneron, Sun Pharma, UCB Pharma, and Ventyx. Jonathan I. Silverberg reports honoraria as a consultant/advisory board member from LEO Pharma and has acted as a consultant for and/or received grants/honoraria from AbbVie, AnaptysBio, Asana Biosciences, Galderma Research and Development, GSK, Glenmark, Kiniksa, LEO Pharma, Lilly, MedImmune, Menlo Therapeutics, Pfizer, PuriCore, Regeneron, and Sanofi. Michael J Cork has served as a clinical trial investigator for Astellas, Galapagos, Johnson & Johnson, LEO Pharma, La Roche-Posay, MSD, Novartis, Perrigo, Regeneron, Sanofi Genzyme, and Stiefel; has served as an advisory board member, consultant, and/or invited lecturer for Pfizer Inc., Amgen, Astellas, Bayer, Johnson & Johnson, LEO Pharma, L’Oréal, MSD, Novartis, Regeneron, Sanofi Genzyme, Stiefel, and Unilever; has received honoraria from Astellas, Johnson & Johnson, LEO Pharma, Novartis, Regeneron, Sanofi Genzyme, and Stiefel; and has received research funding from Bayer. Norito Katoh has received honoraria as a speaker/consultant for Sanofi, Maruho, Abbvie, Ely-Lilly Japan, Taiho Pharmaceutical, Torii Pharmaceutical, and LEO Pharma, and has received grants as an investigator from Maruho, Ely-Lilly Japan, Sun Pharma, Taiho Pharmaceutical, Torii Pharmaceutical, Boehringer Ingelheim Japan, Kyowa Kirin, Jansen Pharma, Boehringer Ingelheim Japan, Abbvie, and LEO Pharma. Thomas Mark was an employee and stockholder of LEO Pharma A/S when conducting the data analyses for this publication. Shannon K.R. Schneider is an employee of LEO Pharma Inc. Andreas Wollenberg has received grants, personal fees, or nonfinancial support from AbbVie, Almirall, Aileens, Beiersdorf, Bioderma, BMS, Chugai, Galapagos, Galderma, GSK, Hans Karrer, Janssen, LEO Pharma, Lilly, L’Oreal, Maruho, MedImmune, Novartis, Pfizer, Pierre Fabre, Regeneron, Santen, and Sanofi-Aventis.

Ethics Approval

The ECZTRA 1 and 2 trials were sponsored by LEO Pharma A/S (Ballerup, Denmark) and conducted in accordance with the ethical principles derived from international guidelines including the Declaration of Helsinki and Council for International Organizations of Medical Sciences International Ethical Guidelines and in compliance with International Council for Harmonisation guidelines for Good Clinical Practice. The clinical trial was approved by institutional review boards or ethics committees at each study site (see ESM). This trial followed the Consolidated Standards of Reporting Trials reporting guideline.

Consent to Participate

All patients provided written informed consent.

Consent for Publication

Not applicable.

Availability of Data and Material

Data will be made available, upon request to the study sponsor, following review by the external Patient and Scientific Review Board.

Code Availability

Not applicable.

Authors’ Contributions

Conceptualization: all authors contributed equally; investigation: all authors contributed equally; data curation: TM (lead); formal analysis: TM (lead); methodology: TM (equal), SKRS (equal); writing: all authors contributed equally; review/editing: all authors contributed equally. All authors read and approved the final version of the manuscript.