P66 Salbutamol therapy in a neuromuscular cohort

• Published in: Neuromuscular disorders : NMD 2023-10, Vol.33, p.S75-S75
• Main Authors: Nigro, E., Amburgey, K., Djordjevic, D., Alawneh, I., Gonorazky, H., Dowling, J.
• Format: Article
• Language: English
• ISSN: 0960-8966; 1873-2364
• DOI: 10.1016/j.nmd.2023.07.047

Salbutamol (or albuterol) is a beta-2 adrenergic agonist primarily used in the management of asthma. The oral form has been used, off-label, for the treatment of several neuromuscular conditions including SMA, CMS, RYR1 myopathy, and FSHD. Several case reports and open label studies have shown improvements in muscle strength, including pulmonary function measurements. Further evidence includes treatment of animal models which have demonstrated increases in skeletal muscle mass, decreases in body fat, and potential improvements in muscle atrophy in degenerative conditions. Limited data and few placebo-controlled trials have been completed to determine the efficacy of salbutamol treatment in neuromuscular conditions. A retrospective chart review of patients treated off label with salbutamol in the neuromuscular clinic at the Hospital for Sick Children will be completed. The primary outcome will assess changes in power via manual muscle testing pre- and post-salbutamol treatment. Secondary outcomes include effects on fatigue, satisfaction with treatment, developmental motor milestones, feeding ability, respiratory function, weight gain, and hospitalizations. In addition, a comparison of effectiveness of treatment based on age, condition, and pre-treatment level of function will be performed. Lastly, dosing and tolerability will be reviewed. We expect to review up to 40 charts of paediatric patients with diagnoses of SMA, non-5q SMA, congenital myopathies, CMS, and other neurogenetic conditions with a prominent neuromuscular component (i.e. PURA syndrome). Efficacy of salbutamol treatment will be assessed in this cohort. Additionally, recommendations for dosing strategy will be proposed for paediatric patients. This study will provide preliminary data and inform the design of future prospective studies and possibly placebo-controlled trials.