Twelve patients with abnormal involuntary movement disorders were
treated with clozapine in a double-blind, placebo-controlled trial. The
cohort consisted of individuals with Gilles de la Tourette's syndrome,
Huntington's disease, and atypical persistent dyskinesia that was drug
induced. Two subjects were dropped from the protocol due to complications.
Two patients with Huntington's disease showed a marked decrease in
movements; other individuals obtained no significant therapeutic benefits.
Seven of the 10 patients completing the trial experienced moderate or
marked side effects.