This discussion reviews data from two 3-week, double-blind, placebo-controlled pivotal trials of carbamazepine extended release capsules (CBZ ERC; SPD417.301 and SPD417.304); pooled results from these trials; data from a 3-week, double-blind, placebo-controlled trial in lithium non-responders or non-tolerators (SPD417.302); and additional supportive data from a 6-month, open-label, extension trial (SPD417.303). In addition, information on a retrospective chart review of 600 adolescent and adult bipolar patients on CBZ ERC is presented.

In the first large double-blind, placebo-controlled study assessing CBZ ERC in acute mania, manic and mixed bipolar patients from multiple centers were hospitalized and all medications were discontinued. After reaching a stable baseline 2–5 days later, the patients were randomized to CBZ ERC (n=101; 59% with mixed states) or placebo (n=103; 47% with mixed states) for 3 weeks. An aggressive initial titration schedule was implemented, beginning with 200 mg BID and increased by 200 mg/day until good clinical response was achieved or the patient could not tolerate the dosage. Many patients were taking 1,200–1,600 mg/day by the end of week 1. Efficacy was assessed using the Young Mania Rating Scale (YMRS). The Clinical Global Impressions (CGI) scale and the Hamilton Rating Scale for Depression (HAM-D) were also followed.