Clinical impact of therapeutic drug monitoring for newer anti-seizure medications in patients with epilepsy: A real-world observation study.

BACKGROUND: The clinical value of therapeutic drug monitoring (TDM) for newer anti-seizure medications (ASMs) remains uncertain. This study aimed to assess the impact of newer ASM TDM on clinical decision making in patients with epilepsy. METHODS: We retrospectively identified all plasma requests for newer ASM level measurement as part of routine clinical management in the outpatient departments of seven medical institutes across Taiwan between September 2016 and May 2019. Data collected from reviewed medical records included clinical and medication details, indications for TDM request, test results, interpretation, and impact on patient management. RESULTS: A total of 682 visits with 1051 plasma samples were included. The most frequently analyzed ASMs were levetiracetam (36.1%), oxcarbazepine (18.4%), and lamotrigine (12.0%). Reasons for TDM included poorly controlled seizures (55.3%), concerns about drug-drug interactions (12.3%), and suspicion of drug overdose (10.6%). 68.8% of samples were within the orienting therapeutic range, even for patients with poorly controlled seizures. TDM for non-adherence concerns showed 54.3% below the orienting therapeutic range, while ASM-related adverse events assessment only 8.9% showed levels exceeding the orienting therapeutic range. Following TDM results, 64.2% of cases had medication adjustments, mainly dosage increases. Overall, 55.9% of newer ASM TDM visit showed improved outcomes, including reduced seizures (47.5%) and fewer ASM-related side effects (8.4%). CONCLUSIONS: These findings suggest that appropriate utilization of TDM for newer ASMs provides clinical benefits in adjunct to complement clinical decision making in the management of epilepsy patients in a real-world clinical setting.

Preliminary Asian experience of using perampanel in clinical practice.

BACKGROUND: To analyze the efficacy and safety of perampanel over a 3-month period in a sample of Asian people with epilepsy. METHODS: The efficacy and safety of perampanel as an adjunctive therapy for patients with epilepsy were retrospectively reviewed and analyzed. Patients were categorized according to seizure type, concomitant antiepileptic drug usage, and perampanel dosage. RESULTS: A total of 210 patients were included in the study and 131 patients completed 3 months of perampanel treatment. The average dosage of perampanel was 5.31 mg/day, and the 50% responder rate (≥50% seizure frequency reduction) in all patients was 45.8%, with a 27.5% seizure-free rate. For focal seizures, focal to bilateral tonic-clonic seizures, and primary generalized seizures, the 50% responder rates were respectively 29.4%, 49.5%, and 36.4%. In total, 39.5% of patients experienced adverse events within 3 months of observation period, and the rate of drug withdrawal due to adverse events was 8.6%. Dizziness, ataxia, irritability/aggression were the most common adverse events. CONCLUSIONS: The efficacy and safety of perampanel in a real-world setting with Asian patients is comparable to that in clinical trials that have included fewer Asian patients.