Quetiapine has been approved for the treatment of major depressive episodes associated with bipolar disorder.
The approval for this indication was made by the Food and Drug Administration based on two 8-week double-blind, placebo-controlled studies of more than 1,000 outpatients.
Quetiapine (Seroquel), an atypical antipsychotic marketed by AstraZeneca, was first approved for treating schizophrenia in 1997 and is now also approved for treating acute manic episodes associated with bipolar I disorder (as either monotherapy or adjunct therapy to lithium or divalproex).
The most recent approval cited the two BOLDER (BipOLar DEpRession) studies of 1,045 outpatients with bipolar I or II disorder, including those with or without a rapid cycling course. Investigators found that patients on 300 mg or 600 mg quetiapine once a day showed improvements in depressive symptoms starting the first week of treatment through 8 weeks that were “superior” to improvements seen among placebo-treated patients, in terms of the reduction in scores on the Montgomery-Asberg Depression Rating Scale, according to the revised package label.
Patients on the 600 mg dosage showed no additional benefit, so the recommended dosage is 300 mg once a day.
In addition, those on 300 mg showed significantly greater improvements in overall quality of life and satisfaction, related to various areas of functioning.
Dry mouth, sedation, somnolence, dizziness, and constipation were the most common adverse events in the bipolar depression studies, according to AstraZeneca.