A randomized controlled pilot trial of lithium in spinocerebellar ataxia type 2.

Spinocerebellar ataxia type 2 (SCA2) is an autosomal dominant disorder. Lithium is able to stimulate autophagy, and to reduce Ca(2+) efflux from the inositol-1,4,5-triphosphate receptor. We designed a phase II, randomized, placebo-controlled, double-blind, 48-week trial with lithium carbonate in 20 patients with SCA2. The primary objective was to determine safety and tolerability of lithium. The secondary objectives were to determine disease progression, quality of life, mood, and brain volume change. Sixteen patients completed the trial, 8 randomized to lithium, 8 to placebo. Forty adverse events (AEs) were reported during the trial, twenty-eight in the lithium and 12 in the placebo group (p = 0.11). Mean AE duration was 57.4 ± 60.8 and 77.4 ± 68.5 days (p = 0.37). Non-significant differences were observed for the SARA and for brain volume change, whereas a significant reduction in the BDI-II was observed for lithium group (p < 0.05). Lithium was well tolerated and reported AEs were similar to those previously described for bipolar disorder patients. A correctly powered phase III trial is needed to assess if lithium may slow disease progression in SCA2.