Long-term Safety and Efficacy of Vigabatrin in Japanese Patients with Infantile Spasms: A Multicenter Open-label Study

Abstract

This clinical study is to evaluate the long-term safety and efficacy of vigabatrin (VGB) in Japanese patients with infantile spasms. A total of 17 patients were treated (maximum treatment duration: 1,380 days), including 7 patients transitioned from the preceding phase III study, 2 patients administered VGB outside of clinical trials, and 8 patients who initiated VGB in this study. In these 8 patients, the daily dose was set during a dose adjustment phase. In the other patients, the daily dose was the same as at the start of the study (≤150 mg/kg/day). Nine patients discontinued the study because of treatment change (7 patients) and adverse drug reactions (2 patients). Adverse drug reactions occurred in 76.5% (13/17 patients) of patients. Notable adverse drug reactions included mild retinal abnormalities (2 patients, unrecovered), asymptomatic magnetic resonance imaging abnormality (1 patient, recovering), and encephalopathy (1 patient, recovered). However, the long-term administration of VGB was generally well tolerated. Spasms disappeared in 6 of 8 patients who completed the study. Follow-up including periodic ophthalmic examination is necessary to address adverse drug reactions such as retinal disorder observed in long-term administration of VGB in patients with infantile spasms. (Funded by Alfresa Pharma Corporation and Sanofi KK)