RESUMEN
BACKGROUND: Facioscapulohumeral muscular dystrophy (FSHD) is a complex, inheritable, and rare muscle disease that affects the entire body. The major symptom of FSHD is progressive weakening and loss of skeletal muscles. The usual location of these weaknesses at onset is the origin of the name: face (facio), shoulder girdle (scapulo), and upper arms (humeral). FSHD appears to have varying molecular and genetic determinants with commensurate differences in disease progression. METHODS: Facioscapulohumeral muscular dystrophy (MD) is probably the most prevalent form of MD but has neither disease-modifying treatments nor a cure. As the mechanism of action becomes further elucidated, more biopharmaceutical companies are investing capital into finding treatments for patients with FSHD. Sponsors of treatments for FSHD patients should be aware of some of the common misconceptions associated with FSHD drug development with the goal of optimizing the chance to prove safety and efficacy for each potential treatment for FSHD in the clinical trial setting. RESULTS: Four major topics with potential clinical manifestations for patients with FSHD will be discussed related to muscle weakness, respiratory issues, animal models and prevalence. CONCLUSION: The authors offer multiple solutions to help counteract misconceptions with each scenario during clinical trial drug development.