Effectiveness of opicapone and switching from entacapone in fluctuating Parkinson disease

Objective To evaluate the effectiveness of opicapone as add-on to levodopa and the effects of switching from entacapone over 1 year of treatment in patients with fluctuating Parkinson disease.

Methods After completion of a placebo- and entacapone-controlled double-blind study of opicapone (5, 25, or 50 mg), 495 patients continued to a 1-year extension phase in which patients were treated with opicapone. Patients began with once-daily opicapone 25 mg for 1 week, followed by individually tailored levodopa and/or opicapone dose adjustments. The primary efficacy variable was the change from baseline in absolute “off” time based on patient diaries. Other outcomes included proportion of responders, scale-based assessments, and standard safety assessments.

Results One year of treatment with opicapone reduced “off” time by a half-hour (33.8 minutes) vs the open-label baseline and >2 hours (126.9 minutes) vs the double-blind baseline. Whereas patients who were originally treated with opicapone 50 mg in the double-blind phase maintained their efficacy, switching treatments led to further decreases in “off” time (−64.9, −39.3, −27.5, and −23.0 minutes for switching from placebo, entacapone, and opicapone 5 and 25 mg, respectively). Dyskinesia was the most frequently reported adverse event (14.5%) and was managed by adjustment of dopaminergic therapy. No new safety concerns were observed with long-term opicapone administration.

Conclusion Long-term use of opicapone provided sustained efficacy over 1 year. Switching from entacapone to opicapone led to enhanced efficacy under the conditions of the study.

Classification of evidence This study provides Class III evidence that for patients with Parkinson disease and end-of-dose motor fluctuations, long-term use (52 weeks) of opicapone is well tolerated and reduces “off” time.