Abstracts

Rationale: Change in depressive symptoms, a key component in assessment of epilepsy treatment, was a secondary endpoint in two clinical trials (045 and 046) of conversion to eslicarbazepine acetate (ESL) monotherapy (1200 mg QD or 1600 mg QD) for patients with partial-onset seizures not controlled by their anti-epileptic drug treatment.Methods: This analysis examined change in depressive symptoms among pooled patients from both trials who converted to ESL monotherapy over an 8-week period and remained on monotherapy for 10 weeks (Completers) and subset of these patients who achieved a reduction in seizure frequency ≥50% (Responders). Mean change (Δ) between baseline and week 18 in the 10-item Montgomery-Åsberg Depression Rating Scale (MADRS; range: 0-60; lower scores indicate less depressive symptoms) was compared to suggested minimal clinically-important differences (MCIDs): 1.3 to 1.6 points at the population level (Duru et al. 2008) and 1 point (compared to active treatment) or 2 points (compared to placebo) at the individual level (Montgomery et al 2009). A paired t-test was used to test for change different than zero.Results: The MADRS was administered at both baseline and week 18, and evaluations were available for 224 (99.1%) Completers and 117 (87.3%) Responders (68.1% and 40.4% of the efficacy population were Completers and Responders, respectively). Among Completers and Responders, depressive symptoms significantly decreased (Δ=‑2.1, p<0.001; Δ=‑2.6, p<0.001, respectively), exceeding the 2-point MCID. Additionally, 56.3% of Completers and 56.4% of Responders reported decreased depressive symptoms (see figure); the majority (90.5% and 87.9%, respectively) decreased 2 or more points. Lastly, there was evidence of a dose-dependent response among Completers (1200 mg: Δ=‑1.3; 1600 mg: Δ=‑2.4) whereas depressive symptoms decreased among Responders regardless of dose (1200 mg: Δ=‑2.8; 1600 mg: Δ=‑2.5).Conclusions: Improvement in depressive symptoms was observed by over half of both patients who successfully converted to ESL monotherapy and patients who responded to ESL monotherapy, with the majority improving above the MCID.