PURPOSE OF REVIEW: Facioscapulohumeral muscular dystrophy (FSHD) is a common muscular dystrophy affecting both pediatric and adult patients. This article reviews the phenotype and pathophysiology of the disease as well as the recent efforts in clinical outcome measures and clinical trials. RECENT FINDINGS: As the name implies, FSHD involves weakness of facial muscles, muscles that fix the scapula, and muscles overlying the humerus (biceps and triceps). The distinctive phenotype of FSHD occurs secondary to two different genetic mechanisms. FSHD type 1 (FSHD1) is due to a deletion on chromosome 4q, leading to hypomethylation and derepression of DUX4. FSHD type 2 (FSHD2) is due to mutations in SMCHD1 with resulting hypomethylation of the same subtelomeric region of chromosome 4q and derepression of DUX4. Understanding the central role of DUX4 has opened up the possibility of disease-modifying treatments. In preparation for clinical trials of novel agents, researchers are in the process of validating a number of clinical trial outcome measures including MRI, the 6-minute walk test, the FSHD Composite Outcome Measure, reachable workspace, electrical impedance myography, and the FSHD Health Index. SUMMARY: The treatment of FSHD is currently supportive only. While past clinical trials in FSHD have been largely disappointing, novel agents in development, including antisense oligonucleotides, gene therapy, and small molecules, hold promise for future meaningful therapies.
PURPOSE OF REVIEW: Facioscapulohumeral muscular dystrophy (FSHD) is a common muscular dystrophy affecting both pediatric and adult patients. This article reviews the phenotype and pathophysiology of the disease as well as the recent efforts in clinical outcome measures and clinical trials. RECENT FINDINGS: As the name implies, FSHD involves weakness of facial muscles, muscles that fix the scapula, and muscles overlying the humerus (biceps and triceps). The distinctive phenotype of FSHD occurs secondary to two different genetic mechanisms. FSHD type 1 (FSHD1) is due to a deletion on chromosome 4q, leading to hypomethylation and derepression of DUX4. FSHD type 2 (FSHD2) is due to mutations in SMCHD1 with resulting hypomethylation of the same subtelomeric region of chromosome 4q and derepression of DUX4. Understanding the central role of DUX4 has opened up the possibility of disease-modifying treatments. In preparation for clinical trials of novel agents, researchers are in the process of validating a number of clinical trial outcome measures including MRI, the 6-minute walk test, the FSHD Composite Outcome Measure, reachable workspace, electrical impedance myography, and the FSHD Health Index. SUMMARY: The treatment of FSHD is currently supportive only. While past clinical trials in FSHD have been largely disappointing, novel agents in development, including antisense oligonucleotides, gene therapy, and small molecules, hold promise for future meaningful therapies.
Authors: Payam Mohassel; Ning Chang; Kaoru Inoue; Angela Delaney; Ying Hu; Sandra Donkervoort; Dimah Saade; B Jeanne Billioux; Brooke Meader; Rita Volochayev; Chamindra G Konersman; Angela M Kaindl; Chie-Hee Cho; Bianca Russell; Adrian Rodriguez; K Wade Foster; A Reghan Foley; Steven A Moore; Peter L Jones; Carsten G Bonnemann; Takako Jones; Natalie D Shaw Journal: Neurology Date: 2022-02-04 Impact factor: 9.910
Authors: Sanne C C Vincenten; Nienke Van Der Stoep; Aimée D C Paulussen; Karlien Mul; Umesh A Badrising; Marjolein Kriek; Olivier W H Van Der Heijden; Baziel G M Van Engelen; Nicol C Voermans; Christine E M De Die-Smulders; Saskia Lassche Journal: Clin Genet Date: 2021-08-01 Impact factor: 4.296