The purpose of this study is to determine if quetiapine fumarate extended-release (quetiapine
XR or SEROQUEL® XR) 150 to 300 mg/day taken by itself is effective and safe in treating
children or adolescents aged 10 to 17 with bipolar depression and if so, how it compares with
placebo (a non-active tablet, like a sugar pill, that looks like quetiapine).