Effectiveness and tolerability of olanzapine in the treatment of adolescents with schizophrenia and related psychotic disorders: results from a large, prospective, open-label study.

OBJECTIVE: The aim of this study was to assess effectiveness and tolerability of oral olanzapine treatment of adolescents with schizophrenic disorders.
METHOD: Adolescent patients (12-19 years) with schizophrenia, schizoaffective, or schizophreniform disorders according to the Diagnostic and Statistical Manual of Mental Disorders, 4(th) edition (DSM-IV) were enrolled in a multicenter, prospective, open-label study. Following a 2- to 9-day washout period, patients initially received 10 mg/day olanzapine. Dose modification was allowed during week 2 (dose range 5-15 mg/day) and during weeks 3-6 (dose range, 5-20 mg/day). Responders (improvement > or =30% on the Brief Psychiatric Rating Scale, BPRS) continued olanzapine for additional 18 weeks. Psychopathology was assessed using BPRS and Clinical Global Impressions (CGI) scales; side effects were assessed by adverse event reporting.
RESULTS: Out of 96 patients enrolled at 10 sites, 60 (62.5%) met response criteria at week 6. Mean BPRS total scores decreased significantly (p < 0.001) from baseline (39.2 +/- 13.4) to week 6 last observation carried forward (LOCF) (22.2 +/- 14.7). The rate of patients considered markedly ill or worse (CGI-S) decreased from 83.3% (baseline) to 37.5% (week 6, LOCF). The most common reported adverse event was weight gain (30.2%, 29/96). Three patients (3.1%) discontinued due to adverse events.
CONCLUSIONS: In this study of young patients with schizophrenia, schizoaffective, or schizophreniform disorders, olanzapine treatment was associated with marked symptom improvement. As changes in weight and prolactin levels may be greater in adolescent than in adult patients, potential risks and benefits of olanzapine treatment in adolescents should be considered carefully.