In this cross-over trial we will investigate the effects of pyridostigmine (mestinon) versus a placebo on fatigability in patients with hereditary proximal spinal muscular atrophy (SMA) types 2, 3 and 4 (aged 12 and older) The study participants will be using a placebo during 8 weeks and mestinon during 8 weeks. Both investigators and patients are blinded to the treatment allocation in both periods. Patients will be randomly assigned to use placebo or mestinon first. At the end of the study, patients will have used both mestinon and a placebo during 8 weeks.~In both phases (periods) of the cross over study, study medication dosage will slowly be increased to a maximum dosage of 6 mg/kg/day (spread over 4 doses daily) in order to either prevent side effects or to manage them as good as possible. This scheme allows us to assist our participants in case side effects do occur early. Although we strive to have all patients on the same dosage per kg of body weight, serious side effects will obviously lead to lowering the dosage.~Before the start of medication use (either placebo or pyridostigmine), baseline measurements will be taken: a physical examination and data concerning both primary and secondary outcomes (MFM, MRC scores, fatigability tests, etc.) will be collected. After use a drug (mestinon/placebo) for 8 weeks these tests will be repeated, to evaluate possible medication effect. After a wash-out period of approximately 1-2 weeks the same scheme is used for the second study period (i.e. the cross-over design). Unblinding follows after the entire study is completed (i.e.: last included patients finishes participation).
A trial investigating the effects of pyridostigmine (mestinon) versus a placebo in a double-blind cross over trial in patients with hereditary proximal spinal muscular atrophy (SMA) types 2, 3 and 4.