Spinocerebellar degeneration.

The spinocerebellar degenerations/ataxias (SCAs) are a diverse group of rare, slowly progressive, neurological diseases, often inherited but of incompletely understood pathophysiology, which affect the cerebellum and its related pathways. They have few animal models and share no reliable biomarkers. They have, as yet, no universally validated rating scale for use in clinical trials. In the past 25 years, there have been, at most, 18 controlled (Class 1) trials for ataxia, which have focused on neurotransmitter mechanisms. There is currently only one National Institute of Neurological Disorders and Stroke-sponsored drug trial for ataxia (Phase I study of idebenone in Friedreich's ataxia). There are, as yet, no FDA-approved drugs for SCA. Current treatment practices encompass rehabilitation interventions and off-label use of symptomatic medications [1,2].