for people ages 18-76 (full criteria)
at La Jolla, California and other locations
study started
estimated completion
Principal Investigator
by Susan Lee
Headshot of Susan Lee
Susan Lee



The purpose of the study is to evaluate the long term safety and efficacy of orally administered M5049 in participants with subacute cutaneous lupus erythematosus (SCLE), discoid lupus erythematosus (DLE) and/or systemic lupus erythematosus (SLE) who have completed the 24 week treatment period of Willow study (MS200569_0003 [NCT05162586]).

Official Title

A Phase II, Double-blind, Dose-Ranging, Parallel, Long-term Extension Study to Evaluate the Safety and Efficacy of Enpatoran in Participants With Subacute Cutaneous Lupus Erythematosus, Discoid Lupus Erythematosus and/or Systemic Lupus Erythematosus Having Completed the WILLOW (MS200569_0003) Study Treatment (WILLOW LTE)


Systemic Lupus Erythematosus Toll-like Receptor 7 Toll-like Receptor 8 WILLOW Adults SLE CLE Lupus Discoid lupus erythematosus Subacute cutaneous lupus erythematosus M5049 Enpatoran LTE Lupus Erythematosus, Systemic M5049 low dose M5049 medium dose M5049 high dose


You can join if…

Open to people ages 18-76

  • Are active SCLE, DLE and/or SLE that have completed the 24 week Treatment of the Willow Study
  • Have a Body Mass Index (BMI) within the range 18.5 to 35 kilograms per meter square (inclusive) at Screening
  • Other protocol defined inclusion criteria could apply

You CAN'T join if...

  • Participants who experienced serious event(s) related to the study intervention during the WILLOW study
  • Other severe acute or chronic medical or psychiatric condition or laboratory abnormality that may increase the risk associated with Long Term Extension (LTE) study participation
  • Ongoing or active clinically significant viral (including Severe acute respiratory syndrome coronavirus 2 [(SARS-CoV-2)], bacterial or fungal infection, or any major episode of infection requiring hospitalization
  • Received LTE prohibited medication during the WILLOW study or after the WILLOW study Week 24
  • Participation in any other investigational drug study after the WILLOW study Week 24
  • Other protocol defined exclusion criteria could apply


  • University of California San Diego Medical Center
    La Jolla California 92093-1503 United States
  • The Lundquist Institute at Harbor-UCLA Medical Center
    Torrance California 90502 United States

Lead Scientist at UCSD

  • Susan Lee
    Clinical Professor, Medicine, Vc-health Sciences-schools. Authored (or co-authored) 27 research publications


not yet accepting patients
Start Date
Completion Date
Merck Healthcare KGaA, Darmstadt, Germany, an affiliate of Merck KGaA, Darmstadt, Germany
Trial Awareness and Transparency website
Phase 2 Lupus Research Study
Study Type
Expecting 440 study participants
Last Updated