Assessment of safety and efficacy of lamotrigine over the course of 1-year observation in Japanese patients with bipolar disorder: post-marketing surveillance study report

Takeshi Terao,1 Atsuko Ishida,2 Toshifumi Kimura,3 Mitsuhiro Yoshida,4 Terufumi Hara2 1Department of Neuropsychiatry, Faculty of Medicine, Oita University, Oita, 2Post-Marketing Surveillance Department, 3MA Specialty & General Care Medicine Department, 4Biomedical Data Sciences Department, Development & Medical Affairs Division, GlaxoSmithKline K.K., Tokyo, Japan Background: A post-marketing surveillance (PMS) study was conducted with a 1-year observation period to assess the safety and efficacy of lamotrigine in routine clinical practice in patients with bipolar disorder (BD).Patients and methods: Central enrollment method was used to recruit patients diagnosed with BD who were being treated for the first time with lamotrigine to prevent the recurrence/relapse of BD mood episodes. Adverse drug reactions (ADRs) and recurrence/relapse were assessed. Improvement of mania and depression was also assessed using the Hamilton’s Rating Scale for Depression (HAM-D) and the Young Mania Rating Scale (YMRS) at treatment initiation, 4–6 months post treatment initiation, and 10–12 months post treatment initiation.Results: A total of 237/989 patients (24.0%) reported ADRs, most commonly rash (9.1%), and the incidence of serious ADRs was 3.3% (33/989 patients). Skin disorders occurred in 130 patients (13.1%), mostly within 8 weeks post treatment. A total of 237/703 patients (33.7%) experienced recurrence/relapse of mood episodes. The 25th percentile of the time to recurrence/relapse of mood episodes was 105 days. Remission of depression symptoms (HAM-D ≤7) occurred in 147/697 patients (21.1%) at treatment initiation, rising to 361 patients (67.4%) at 10–12 months post treatment. Remission of manic symptoms (YMRS ≤13) occurred in 615/676 patients (91.0%) at treatment initiation, rising to 500 patients (97.3%) at 10–12 months post treatment.Conclusion: The results of this PMS study suggest that lamotrigine is a well-tolerated and effective drug for preventing recurrence/relapse of BD in clinical practice. Keywords: lamotrigine, bipolar, mood episode, post-marketing surveillance study, safety, efficacy