Periodic salbutamol in facioscapulohumeral muscular dystrophy: a randomized controlled trial

To evaluate the effects on muscle strength of salbutamol administered for 6 months using a periodic regimen in patients presenting with facioscapulohumeral muscular dystrophy (FSHD).

Placebo-controlled double-blind randomized study.

Three clinical centers involved in neuromuscular disorders.

Ambulatory patients (N=112), 56 per group, with genetically confirmed FSHD, age 18 to 60 years.

Salbutamol (sustained released formulation) administered orally at a daily dose of 16 mg using a periodic dosage regimen (3 wks on, 1 wk off).

Muscle strength was assessed with quantitative muscle testing (QMT), manual muscle testing (MMT), and timed motor tests. Patients were evaluated at baseline, and 3 and 6 months later. Plasma drug assays were carried out at each visit.

There was no significant change with periodic use of salbutamol in the total composite QMT z-score, MMT score, or timed motor tests. Salbutamol was well tolerated. Lack of efficacy did not seem to be related to plasma concentrations, which were within the expected range.

Results from this study and previous controlled trials preclude at present the use of salbutamol as routine treatment for FSHD, even if we cannot exclude improvement from anabolic effects with a longer duration of treatment.