This is a multicenter, randomized, parallel-group, double-blind, placebo-controlled study to
evaluate the efficacy and safety of quetiapine and lithium (comparator in the study) for up
to 104 weeks of maintenance treatment in adult patients with Bipolar I Disorder.
PLEASE NOTE: Seroquel SR and Seroquel XR refer to the same formulation. The SR designation
was changed to XR after consultation with FDA.