for people ages 18-65 (full criteria)
at Irvine, California and other locations
study started
completion around



This is a study to evaluate the safety and efficacy of losmapimod in treating participants with Facioscapulohumeral Muscular Dystrophy (FSHD). Participants diagnosed with Facioscapulohumeral muscular dystrophy type 1 (FSHD1) or Facioscapulohumeral muscular dystrophy type 2 (FSHD2) will participate in Part A (Placebo-controlled treatment period) and will be randomized in a 1:1 ratio to receive losmapimod 15 milligrams (mg) or placebo orally twice daily (BID). Upon completion of Part A, participants will have the option to rollover into Part B (open-label extension) to evaluate the long-term safety, tolerability, and efficacy of losmapimod and will receive losmapimod 15 mg orally BID.

Official Title

A Phase 3 Global, Randomized, Double-Blind, Placebo-Controlled, 48-Week, Parallel-Group Study of the Efficacy and Safety of Losmapimod in Treating Patients With Facioscapulohumeral Muscular Dystrophy (FSHD) (REACH)


Facioscapulohumeral Muscular Dystrophy (FSHD), Facioscapulohumeral muscular dystrophy type 1 (FSHD 1), Facioscapulohumeral muscular dystrophy type 2 (FSHD 2), Muscular Dystrophies, Muscular Dystrophy, Facioscapulohumeral Muscular Disorders, Musculoskeletal Diseases, Neuromuscular Diseases, REACH, Facioscapulohumeral Muscular Dystrophy, Losmapimod, Open-label extension


You can join if…

Open to people ages 18-65

  • Participants must be between 18 and 65 years of age, inclusive.
  • Genetically confirmed diagnosis of FSHD 1 or FSHD 2.
  • Clinical severity score of 2 to 4 (Ricci Score; Range 0-5), at screening. Participants who are wheelchair-dependent or dependent on walker or wheelchair for activities are not permitted to enroll in the study.
  • Screening total RSA (Q1-Q4) without weight in the dominant UE assessed by RWS ≥ 0.2 and ≤ 0.7.
  • No contraindications to MRI.

You CAN'T join if...

  • Previously diagnosed cancer that has not been in complete remission for at least 5 years. Localized carcinomas of the skin and carcinoma in situ of the cervix that have been resected or ablated for cure are not exclusionary.
  • Participants who are on drug(s) or supplements that may affect muscle function, as determined by the Investigator: participants must be on a stable dose of that drug(s) or supplement for at least 3 months prior to the first dose of study drug and remain on that stable dose for the duration of the study.
  • Known active opportunistic or life-threatening infections including Human Immunodeficiency virus (HIV) and hepatitis B or C.
  • Known active or inactive tuberculosis infection.
  • Acute or chronic history of liver disease.
  • Known severe renal impairment.
  • History of cardiac dysrhythmias requiring anti-arrhythmia treatment(s); or history or evidence of abnormal ECGs.
  • Use of another investigational product within 30 days or 5 half-lives (whichever is longer) or currently participating in a study of an investigational device.
  • Current or anticipated participation in a natural history study. Previous participation is allowed but participants cannot continue after enrollment in Study 1821-FSH-301.
  • Known hypersensitivity to losmapimod or any of its excipients.
  • Previous participation in a Fulcrum-sponsored FSHD losmapimod study (FIS-001-2019 or FIS-002-2019).

Note that all other inclusion and exclusion criteria are listed in the protocol and only key are presented.


  • University of California Irvine
    Irvine California 92868 United States
  • University of California Los Angeles (UCLA)
    Los Angeles California 90095 United States


in progress, not accepting new patients
Start Date
Completion Date
Fulcrum Therapeutics
Phase 3 Facioscapulohumeral Muscular Dystrophy Research Study
Study Type
About 260 people participating
Last Updated