A Clinical Trial to Determine the Long-term Safety and Tolerability of an Investigational Drug in People With Major Depressive Episode Associated With Bipolar I Disorder (Bipolar I Depression).

This is a 12-month open-label safety extension study to evaluate the long-term safety, tolerability, and effectiveness of SEP-4199 CR 200-400 mg/day in the treatment of subjects with bipolar I depression who previously completed a lead-in study of SEP-4199 CR. The study will consist of a 12-month open-label flexible-dose treatment period, and a safety follow-up period. There are 15 scheduled visits, including a Baseline visit, 13 visits during the open-label treatment period, and 1 safety follow-up visit 7 (± 2) days after the last dose of study drug. If necessary, subjects may return to the clinic at anytime for an unscheduled visit