Adherence with Extended-Release Oxcarbazepine (Oxtellar XR®) vs. Immediate-Release Oxcarbazepine: Analysis of Pooled Data from Four National Pharmacy Claims Databases (P6.293)

Objective: To assess adherence measured as Medication Possession Ratio (MPR) in epilepsy patients switched from b.i.d. immediate-release oxcarbazepine (OXC-IR) to q.d. extended-release oxcarbazepine (Oxtellar XR®, Supernus Pharmaceuticals), using pooled data from national pharmacy claims databases. Background: An inverse relationship between medication adherence and healthcare resource use is well documented. Extended-release (XR) formulations are designed to produce more favorable plasma concentration-time profiles, reduce dose frequency, and improve tolerability in order to increase adherence vs. their immediate-release counterparts. Design/Methods: Design: Retrospective observational study analyzing pooled pharmacy claims data from commercial databases (Truven MarketScan®, IMS LifeLink PharMetrics Plus™ Database, OptumInsight Clinformatics™ Data Mart Research Database, Optum Impact National Benchmark™ Dataset). Key inclusion criteria: ≥1 Oxtellar XR pharmacy claim (first claim=index date); age ≥6 yrs at index date; continuous plan enrollment 6 months pre- and 12 months post-index; epilepsy diagnosis. Analysis cohort: Subjects with OXC-IR pharmacy claim in 6-month period before Oxtellar XR index claim. Analysis: OXC-IR MPR vs. post-switch Oxtellar XR MPR. MPR=total days of drug supply divided by days between first and last dispensing of drug plus days of last dispensed supply. Results: 529 patients switched from OXC-IR to Oxtellar XR. Mean MPR increased from 73% with OXC-IR to 81% (p Conclusions: The switch from OXC-IR to Oxtellar XR was associated with a significant increase in medication adherence, as measured by MPR. This study adds further support to the use of extended-release AEDs as a strategy to improve adherence and medication management. Study Supported by: Supernus Pharmaceuticals, Inc. Disclosure: Dr. Mendes has received personal compensation for consulting, serving on a scientific advisory board, speaking, or other activities with Supernus Pharmaceuticals, Inc. Dr. O9Neal has received personal compensation for consulting, serving on a scientific advisory board, speaking, or other activities with Supernus Pharmaceuticals, Inc. Dr. Baser has received research support from Supernus Pharmaceuticals, Inc. Dr. Wang has received research support from Supernus Pharmaceuticals, Inc. Dr. Cramer has received personal compensation for consulting, serving on a scientific advisory board, speaking, or other activities with UCB, Sunovion, Supernus, Sun, Liva-Nova.