Abstracts

Rationale: Lacosamide (LCM) is currently approved in the US as adjunctive therapy for partial-onset seizures (POS). Results from a historical-controlled, multicenter, double-blind, randomized, conversion to LCM monotherapy trial have recently been presented. Our study explored the real-world characteristics of patients with epilepsy treated with LCM monotherapy, including patient demographics, co-morbidities, and patterns of antiepileptic drug (AED) use prior to and following LCM monotherapy. Methods: A retrospective cohort study was conducted using IMS' PharMetrics Plus health plan claims database. Patients with epilepsy (ICD-9 CM 345.x or 780.3x) ≥17 years in age when starting LCM monotherapy (index date), and receiving ≥ 90 days LCM monotherapy were identified between June 1, 2009 and September 30, 2012. Patients had continuous follow-up for a minimum of 12 months pre- and post-index. Pre-index AED use was evaluated during the 6 months preceding the index date and is reported as the proportion of patients with either: 1) AED monotherapy; 2) LCM adjunctive therapy (LCM treatment overlapped with another AED for ≥ 90 days); 3) AED combination therapy without LCM (two AEDs with ≥ 90 days overlap); or 4) no prior use of AED. Patients were followed for 12 months post-index to evaluate: adherence to LCM monotherapy (measured by proportion of days covered [PDC]), and LCM monotherapy modifications: discontinuation, add-on, or switch to another AED. Results: A total of 746 patients were eligible for analysis. The mean (SD) age was 43.3 (16.1) years, 60.0% were female, and 98.5% were commercially insured. Common comorbidities of interest included hypertension (34.2%), depression (21.6%), intellectual/developmental disability (21.4%), anxiety (13.4%) and head trauma/traumatic brain injury (12.9%). Prior to initiating or converting to LCM monotherapy, 18.5% were AED-naïve, 37.4% were treated with AED monotherapy, and 2.9% were treated with non-LCM AED combinations. The remaining 41.2% used both LCM and another AED prior to monotherapy; 41% of those having ≥ 90 days overlap with another AED prior to conversion to monotherapy. During the follow-up period, most patients (69.8%, n=521) continued with LCM in their treatment regimen, either as monotherapy or after adding another AED. While patients were on LCM monotherapy, mean (SD) PDC was 0.85 (0.17); 13.0% (n=97) switched to another AED; 13.1% (n=98) discontinued LCM; and 4.0% (n=30) discontinued and restarted LCM. Conclusions: In this real-world study, epilepsy patients were experiencing similar co-morbidities to those found in other studies. Results showed that the majority of patients converted to LCM monotherapy from either adjunctive therapy with LCM or from monotherapy with another AED. Following LCM monotherapy initiation, the majority of patients maintained a LCM-containing regimen during 12 months follow-up. Patient adherence to LCM monotherapy was good. Study sponsored by UCB, Inc.