• The effects of protirelin were compared with those of placebo in a multi-institutional, double-blind, controlled study of 143 chronic schizophrenic patients. Treatment with neuroleptics was continued during the study and 4 mg protirelin per day was orally administered for 14 days.
Protirelin appeared to be significantly superior to placebo on the physicians' global ratings of efficacy. Increased motivation for work was isolated as a target effect but such symptoms as facial expression, emotional rapport, and psychomotor activity also appeared to be improved by addition of protirelin to the neuroleptics. Onset of the therapeutic effect of protirelin occurred within a week of medication in most of the patients who showed improvement. No adverse reactions were encountered.