Olanzapine versus divalproex sodium for the treatment of acute mania and maintenance of remission: a 47-week study. Comparative evaluation of olanzapine efficacy in the maintenance treatment of bipolar disorder. Olanzapine versus lithium in the maintenance treatment of bipolar disorder: a 12-month, randomized, double-blind, controlled clinical trial. Relapse prevention in bipolar I disorder: 18-month comparison of olanzapine plus mood stabiliser v. mood stabiliser alone. Randomized, placebo-controlled trial of olanzapine as maintenance therapy in patients with bipolar I disorder responding to acute treatment with olanzapine.
Few double-blind trials have compared longer-term efficacy and safety of medications for bipolar disorder. The authors report a 47-week comparison of olanzapine and divalproex.
                This 47-week, randomized, double-blind study compared flexibly dosed olanzapine (5-20 mg/day) to divalproex (500-2500 mg/day) for manic or mixed episodes of bipolar disorder (N=251). The only other psychoactive medication allowed was lorazepam for agitation. The primary efficacy instrument was the Young Mania Rating Scale; a priori protocol-defined threshold scores were > or =20 for inclusion, < or =12 for remission, and > or = 15 for relapse. Analytical techniques included mixed model repeated-measures analysis of variance for change from baseline, Fisher's exact test (two-tailed) for categorical comparisons, and Kaplan-Meier estimates of time to events of interest.
                Over 47 weeks, mean improvement in Young Mania Rating Scale score was significantly greater for the olanzapine group. Median time to symptomatic mania remission was significantly shorter for olanzapine, 14 days, than for divalproex, 62 days. There were no significant differences between treatments in the rates of symptomatic mania remission over the 47 weeks (56.8% and 45.5%, respectively) and subsequent relapse into mania or depression (42.3% and 56.5%). Treatment-emergent adverse events occurring significantly more frequently during olanzapine treatment were somnolence, dry mouth, increased appetite, weight gain, akathisia, and high alanine aminotransferase levels; those for divalproex were nausea and nervousness.
                In this 47-week study of acute bipolar mania, symptomatic remission occurred sooner and overall mania improvement was greater for olanzapine than for divalproex, but rates of bipolar relapse did not differ. nan The authors compared the efficacy of olanzapine and lithium in the prevention of mood episode relapse/recurrence.
                Patients with a diagnosis of bipolar disorder (manic/mixed), a history of two or more manic or mixed episodes within 6 years, and a Young Mania Rating Scale total score > or =20 entered the study and received open-label co-treatment with olanzapine and lithium for 6-12 weeks. Those meeting symptomatic remission criteria (Young Mania Rating Scale score < or =12; 21-item Hamilton depression scale score < or =8) were randomly assigned to 52 weeks of double-blind monotherapy with olanzapine, 5-20 mg/day (N=217), or lithium (target blood level: 0.6-1.2 meq/liter) (N=214).
                Symptomatic relapse/recurrence (score > or =15 on either the Young Mania Rating Scale or Hamilton depression scale) occurred in 30.0% of olanzapine-treated and 38.8% of lithium-treated patients. The noninferiority of olanzapine relative to lithium (primary objective) in preventing relapse/recurrence was met, since the lower limit of the 95% confidence interval on the 8.8% risk difference (-0.1% to 17.8%) exceeded the predefined noninferiority margin (-7.3%). Secondary results showed that compared with lithium, olanzapine had significantly lower risks of manic episode and mixed episode relapse/recurrence. Depression relapse/recurrence occurred in 15.7% of olanzapine-treated and 10.7% of lithium-treated patients. Mean weight gain during open-label co-treatment was 2.7 kg; during double-blind monotherapy, weight gain was significantly greater with olanzapine (1.8 kg) than with lithium (-1.4 kg).
                These results suggest that olanzapine was significantly more effective than lithium in preventing manic and mixed episode relapse/recurrence in patients acutely stabilized with olanzapine and lithium co-treatment. Both agents were comparable in preventing depression relapse/recurrence. Few controlled studies have examined the use of atypical antipsychotic drugs for prevention of relapse in patients with bipolar I disorder. Aims To evaluate whether olanzapine plus either lithium or valproate reduces the rate of relapse, compared with lithium or valproate alone.
                Patients achieving syndromic remission after 6 weeks'treatment with olanzapine plus either lithium (0.6-1.2 mmol/l) or valproate (50-125 microg/ml) received lithium or valproate plus either olanzapine 5-20 mg/day (combination therapy) or placebo (monotherapy), and were followed in a double-masked trial for 18 months.
                The treatment difference in time to relapse into either mania or depression was not significant for syndromic relapse (median time to relapse: combination therapy 94 days, monotherapy 40.5 days; P=0.742), but was significant for symptomatic relapse (combination therapy 163 days, monotherapy 42 days; P=0.023).
                Patients taking olanzapine added to lithium or valproate experienced sustained symptomatic remission, but not syndromic remission, for longer than those receiving lithium or valproate monotherapy. In a placebo-controlled, double-blind study, the authors investigated the efficacy and safety of olanzapine as monotherapy in relapse prevention in bipolar I disorder.
                Patients achieving symptomatic remission from a manic or mixed episode of bipolar I disorder (Young Mania Rating Scale [YMRS] total score < or =12 and 21-item Hamilton Depression Rating Scale [HAM-D] score <or =8) at two consecutive weekly visits following 6-12 weeks of open-label acute treatment with 5-20 mg/day of olanzapine were randomly assigned to double-blind maintenance treatment with olanzapine (N=225) or placebo (N=136) for up to 48 weeks. The primary measure of efficacy was time to symptomatic relapse into any mood episode (YMRS score > or =15, HAM-D score > or =15, or hospitalization).
                Time to symptomatic relapse into any mood episode was significantly longer among patients receiving olanzapine (a median of 174 days, compared with a median of 22 days in patients receiving placebo). Times to symptomatic relapse into manic, depressive, and mixed episodes were all significantly longer among patients receiving olanzapine than among patients receiving placebo. The relapse rate was significantly lower in the olanzapine group (46.7%) than in the placebo group (80.1%). During olanzapine treatment, the most common emergent event was weight gain; during the open-label phase, patients who received olanzapine gained a mean of 3.1 kg (SD=3.4). In double-blind treatment, placebo patients lost a mean of 2.0 kg (SD=4.4) and patients who continued to take olanzapine gained an additional 1.0 kg (SD=5.2).
                Compared to placebo, olanzapine delays relapse into subsequent mood episodes in bipolar I disorder patients who responded to open-label acute treatment with olanzapine for a manic or mixed episode.
Though based on a limited amount of information, there is evidence that olanzapine may prevent further mood episodes in patients who have responded to olanzapine during an index manic or mixed episode and who have not previously had a satisfactory response to lithium or valproate. However, notwithstanding these positive results, the current evidence is stronger for lithium as first line maintenance treatment of bipolar disorder.