Efficacy of low to moderate doses of oxcarbazepine in adult patients with newly diagnosed partial epilepsy

PURPOSE The objective of this study was to explore the efficacy of low dose of oxcarbazepine (OXC) in adult patients with newly diagnosed partial epilepsy in an actual clinical setting. The associated factors influencing the poor control of seizures were also evaluated. METHODS The epilepsy database (2010-2014) from the Epilepsy Clinic of West China Hospital was retrospectively reviewed. RESULTS A total of 102 adult patients with newly diagnosed, previously untreated partial epilepsy initially treated with OXC were included, and divided into good response group (64) and poor response group (38) according to whether they were seizure-free for at least 12 months. There were 27 (26.5%) patients becoming seizure-free with OXC 600 mg/day monotherapy. The remaining 75 patients had doses of either increasing OXC to 900 mg/day (n = 59) or the addition of another antiepileptic drug (AED) (n = 16), with another 20 (19.6%) and six (5.9%) patients becoming seizure-free, respectively (P = 0.788). In addition, two (2.0%) and nine (8.8%) patients became seizure-free with OXC > 900 mg/day monotherapy and OXC ≥ 900 mg/day combination therapy, respectively. Multivariate binary logistic regression analysis revealed that the time from onset of epilepsy to treatment initiation is significantly associated with seizure control (P = 0.02). CONCLUSION Our results indicated that OXC at low to moderate doses is effective for the treatment of Chinese adult patients with newly diagnosed, previously untreated partial epilepsy, and a longer time interval from the onset of epilepsy to the start of treatment significantly predicts poor seizure control.