Olanzapine versus placebo: results of a double-blind,fixed-dose olanzapine trial

Olanzapine is a potential new atypical antipsychotic agent. This double-blind, acute phase study compared two doses of olanzapine [1 mg/day (Olz1.0); 10 mg/day (Olz10.0)] with placebo in the treatment of 152 patients who met the DSM-III-R criteria for schizophrenia and had a Brief Psychiatric Rating Scale (BPRS)-total score (items scored 0–6) 24. In overall symptomatology improvement [BPRS-total score and Positive and Negative Syndrome Scale (PANSS)-total score], Olz10.0 was statistically significantly superior to placebo. In positive symptom improvement (PANSS-positive score, BPRS-positive score), Olz10.0 was statistically significantly superior to placebo. In negative symptom improvement (PANSS-negative score), Olz10.0 was statistically superior to placebo. Olz 1.0 was clinically comparable to placebo in all efficacy comparisons. The only adverse event to show an overall statistically significant incidence difference was anorexia (reported for 10% of placebo-treated and 0% of Olz10.0-treated patients). The Olz10.0-treated patients improved over baseline with respect to parkinsonian and akathisia symptoms, and these changes were comparable with those observed with placebo. There were no dystonias associated with Olz10.0 treatment. At endpoint, the incidence of patients with elevated prolactin values did not differ statistically significantly between placebo-treated and Olz10.0-treated patients. Olanzapine appears to be not only safe and effective, but a promising atypical antipsychotic candidate.This study was funded by Eli Lilly and Company The HGAP Study Group: Alan Green, Massachusetts Mental Health Center, Boston, Mass.; Sharon Dott, Department of Psychiatry, U.T.M.B., Galveston, Texas; Greg Pfister and Luisito Roxas, Psychiatry Clinic, St Alexius Medical Center, Bismarck, North Dakota; Joyce Small, Department of Psychiatry, Indiana University School of Medicine, Indianapolis, Ind.; Marshall Thomas, Colorado Psychiatric Hospital, Denver, Co.; Donna Ames, VA Medical Center, West Los Angeles, Brentwood Division, Los Angeles, Calif.; Nina Schooler and Robert Baker, Special Studies Division, Mayview State Hospital, Bridgeville, Pa.; Robert Levine, New York, N.Y.; Louis Fabre, Fabre Research Clinic, Inc., Houston, Texas; Robert Friedel, University of Alabama Birmingham Clinical Research, Birmingham, Alabama; Allen Safferman and Jeffrey Lieberman, Hillside Hospital, A Division of Long Island Jewish Medical Center, Glen Oaks, N.Y.; Stephen Stahl, Institute for Psychopharmacology Research, San Diego, Calif.