Efficacy of opicapone in Parkinson’s disease patients according to baseline pramipexole use: A post-hoc analysis from combined BIPARK-I and II

Abstract

To evaluate opicapone’s (OPC) efficacy in levodopa-treated Parkinson’s Disease (PD) patients with or without concurrent pramipexole use (CPU). OPC, a once-daily COMT inhibitor, proved effective in the treatment of motor fluctuations in PD patients in two large, pivotal, multinational trials (BIPARK-I and II) [[1]Ferreira et al.Lancet Neurol. 2016; 15: 154-165Google Scholar,[2]Lees et al.JAMA Neurol. 2017; 74: 197-206Google Scholar]. Patient-level data from matching treatment arms in BIPARK-I and II were combined in placebo (PLC) and OPC-50 mg groups. Studies had similar designs (primary efficacy endpoint: change from baseline in patient diaries-based absolute OFF-time) and eligibility criteria [[1]Ferreira et al.Lancet Neurol. 2016; 15: 154-165Google Scholar,[2]Lees et al.JAMA Neurol. 2017; 74: 197-206Google Scholar]. This exploratory post-hoc analysis was performed to evaluate OPC-50 mg and PLC efficacies in levodopa-treated PD patients with or without baseline CPU (the most commonly used dopamine agonist). In total, 535 patients were randomized; Full Analysis Set comprised 517 [PLC (n = 255); OPC-50 mg (n = 262)]. About 37% of patients in each arm were using pramipexole at baseline. Mean placebo-adjusted OFF-time reductions were −89.0 min (p = 0.0001) and −39.8 min (p = 0.0165) for OPC-50 mg patients with and without CPU. There was ~45% more OFF-time reduction in PLC patients without CPU than in those with, but ~20% less OFF-time reduction in OPC-50 mg patients without CPU than in those with. A higher-than-PLC proportion of OPC-50 mg-receiving patients with CPU achieved OFF- (72.9% vs. 40.4%; p < 0.0001) and ON-time (68.8% vs. 42.6%; p = 0.0003) responders’ endpoint. Consistently, a higher-than-PLC proportion of OPC-50 mg-receiving patients without CPU achieved OFF- (64.5% vs. 54.0%; p = 0.0551) and ON-time (60.2% vs. 47.2%; p = 0.0169) responders’ endpoint. Opicapone was effective regardless of concurrent pramipexole use.