A Study in the Treatment of Acute Mania

The primary objective is to show that the efficacy of olanzapine is non-inferior to the conventional antipsychotics haloperidol or zuclopentixol in the treatment of an acute manic or mixed episode of bipolar disorder. Efficacy is defined as time to remission, as measured by the total scores of the Young Mania Rating Scale (Y-MRS), MADRS-S, and Clinical Global Impression - Bipolar (CGI-BP). Time from baseline to remission is defined as the primary efficacy measure. Remission is defined as a Y-MRS score \<=12 AND a MADRS-S score \<=12 AND CGI-BP = 1 or 2. Secondary efficacy assessments will include time from baseline to * Response, as defined as a reduction of Y-MRS score greater than or equal to 50% compared to baseline * Relapse of mania, as defined as a Y-MRS score \>= 16 AND CGI-BP \>2 after having met the criteria for remission * Switch into depression, as defined as a MADRS-S score \>=17 AND fulfilled criteria for Major Depression as self-assessed by DSRS.