Topical niclosamide (ATx201) reduces Staphylococcus aureus colonization and increases Shannon diversity of the skin microbiome in atopic dermatitis patients in a randomized, double-blind, placebo-controlled Phase 2 trial

Research output: Contribution to journalJournal articleResearchpeer-review


  • Fulltext

    Final published version, 4.93 MB, PDF document

  • Anne Weiss
  • Emilie Delavenne
  • Carina Matias
  • Heimo Lagler
  • Daniel Simon
  • Ping Li
  • Jon U Hansen
  • Teresa Pires Dos Santos
  • Bimal Jana
  • Petra Priemel
  • Christine Bangert
  • Martin Bauer
  • Sabine Eberl
  • Alina Nussbaumer-Pröll
  • Zoe Anne Österreicher
  • Peter Matzneller
  • Tamara Quint
  • Maria Weber
  • Wooseong Kim
  • Eleftherios Mylonakis
  • Christian Friis
  • John Pace
  • Carina Vingsbo Lundberg
  • Fatima M'Zali
  • Pascal Butty
  • Nikolaj Sørensen
  • Henrik Bjørn Nielsen
  • Rasmus Toft-Kehler
  • Emma Guttman-Yassky
  • Georg Stingl
  • Markus Zeitlinger
  • Morten Sommer

BACKGROUND: In patients with atopic dermatitis (AD), Staphylococcus aureus frequently colonizes lesions and is hypothesized to be linked to disease severity and progression. Treatments that reduce S. aureus colonization without significantly affecting the skin commensal microbiota are needed.

METHODS AND FINDINGS: In this study, we tested ATx201 (niclosamide), a small molecule, on its efficacy to reduce S. aureus and propensity to evolve resistance in vitro. Various cutaneous formulations were then tested in a superficial skin infection model. Finally, a Phase 2 randomized, double-blind and placebo-controlled trial was performed to investigate the impact of ATx201 OINTMENT 2% on S. aureus colonization and skin microbiome composition in patients with mild-to-severe AD (EudraCT:2016-003501-33). ATx201 has a narrow minimal inhibitory concentration distribution (.125-.5 μg/ml) consistent with its mode of action - targeting the proton motive force effectively stopping cell growth. In murine models, ATx201 can effectively treat superficial skin infections of methicillin-resistant S. aureus. In a Phase 2 trial in patients with mild-to-severe AD (N = 36), twice-daily treatment with ATx201 OINTMENT 2% effectively reduces S. aureus colonization in quantitative colony forming unit (CFU) analysis (primary endpoint: 94.4% active vs. 38.9% vehicle success rate, p = .0016) and increases the Shannon diversity of the skin microbiome at day 7 significantly compared to vehicle.

CONCLUSION: These results suggest that ATx201 could become a new treatment modality as a decolonizing agent.

Original languageEnglish
Article numbere790
JournalClinical and Translational Medicine
Issue number5
Publication statusPublished - 2022

Bibliographical note

© 2022 The Authors. Clinical and Translational Medicine published by John Wiley & Sons Australia, Ltd on behalf of Shanghai Institute of Clinical Bioinformatics.

    Research areas

  • Animals, Anti-Bacterial Agents/pharmacology, Dermatitis, Atopic/drug therapy, Humans, Methicillin-Resistant Staphylococcus aureus, Mice, Microbiota, Niclosamide/pharmacology, Ointments/pharmacology, Staphylococcal Infections/drug therapy, Staphylococcus aureus

Number of downloads are based on statistics from Google Scholar and

No data available

ID: 322672163