We examined the efficacy and safety of flexibly-dosed olanzapine for the treatment of borderline personality disorder (BPD).

In this 12-week double-blind trial, patients 18-65 years of age with a diagnosis of DSM-IV BPD received olanzapine (2.5-20mg/day; N=155) or placebo (N=159). The primary efficacy measure was the change from baseline to last-observation carried forward endpoint (LOCF) on the Zanarini Rating Scale for BPD (ZAN-BPD) total score. Rate of response and time to response were also examined, with response defined as a >=50% reduction in ZAN-BPD total score.

Mean baseline ZAN-BPD total scores were indicative of moderate symptom severity (olanzapine 17.01 vs. placebo 17.70, p=0.156). Both treatment groups showed significant improvements in overall symptom severity, based on mean changes from baseline to LOCF endpoint in ZAN-BPD total score, but did not differ in the magnitude of improvement at endpoint (olanzapine -6.56 vs. placebo -6.25, p=.661). Response rates did not differ between treatment groups (olanzapine 64.7% vs. placebo 53.5%, p=.062); however, time to response was significantly shorter for the olanzapine treatment group (p=.022). Treatment-emergent adverse events reported significantly more frequently among olanzapine-treated patients included somnolence, sedation, increased appetite and weight increase. Mean weight change from baseline to endpoint was significantly different for olanzapine- relative to placebo-treated patients (2.86vs. -0.35kg, p<.001).

Both the olanzapine- and placebo-treated patients showed significant but not statistically different improvement on overall symptoms of borderline personality disorder. The types of adverse events observed with olanzapine treatment were similar to those seen previously in adult populations.