Opicapone odds ratio in relative off-time reduction: A post-hoc analysis from combined BIPARK-I and II data

Abstract

Objective To evaluate the opicapone (OPC) associated patient’s odds ratio (OR) in relative OFF-time reduction. 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 , 2 ]. Methods Patient-level data from matching treatment arms in BIPARK-I and II were combined in placebo (PLC) and OPC-50mg groups. The studies had similar designs (primary efficacy endpoint: change from baseline in patient diaries-based absolute OFF-time) and eligibility criteria [ 1 , 2 ]. An exploratory post hoc analysis was performed evaluating the associated patient’s OR in relative OFF-time reduction, in each treatment group, at different cut-offs, namely ≥25%, ≥50%, ≥75% and 100% (OFF-time free). Statistical analysis was performed by a pairwise Cochran-Mantel-Haenszel test stratified by study. Results In total, 535 patients were randomized; Full Analysis Set comprised 517 [PLC (n=255); OPC-50mg (n=262)]. The proportion of OFF-time responders for 50mg-OPC was higher than placebo for all different cut-offs, reaching statistical significance for both ≥25 (p = 0.0002) and ≥50% (p = 0.0223) relative OFF-time reduction. PLC proportion of responders ranged from 38.0% (≥ 25%) to 4.7% (100%). OPC-50mg proportion of responders ranged from 54.6% (≥25%) to 8.0% (100%) and presented an OR to placebo ranging from 1.94 (≥25%) to 1.75 (100%).