Category: Parkinson’s Disease: Clinical Trials
Objective: The EPSILON study aimed to explore the potential of opicapone (OPC) to enhance the clinical benefit of levodopa/dopa decarboxylase inhibitor (DDCi) in patients with Parkinson’s disease (PD) without motor complications.
Background: Adding catechol-O-methyltransferase (COMT) inhibitors to levodopa/DDCI therapy represent one of the most commonly used strategies to manage motor complications in patients with PD. The COMT inhibitor OPC demonstrated efficacy in reducing OFF-time in levodopa/DDCi-treated patients with PD and end-of-dose motor fluctuations (MF) and is generally well tolerated.
Method: In this double-blind, multicentre, randomised, placebo-controlled study, 355 PD patients without MF treated with levodopa/DDCi and other anti-PD medications were randomised (1:1) to OPC 50 mg once-daily or placebo. A 4-week screening period was followed by a 24-week maintenance phase. Primary efficacy endpoint was change from baseline to week 24 in Movement Disorder Society-Unified PD Rating Scale (MDS-UPDRS)-III. Secondary endpoints included tolerability, Clinical and Patient Global Impression of Improvement/Change (CGI-I/PGI-C) and MDS-UPDRS-IV.
Results: At week 24, mean (standard error [SE]) change from baseline in MDS-UPDRS-III score for the OPC group was -6.5 (0.7) versus -4.3 (0.7) for the placebo group, with a significant -2.2 (0.9) difference favouring OPC (p=0.010). Compared with placebo-treated patients, significantly more OPC-treated patients reported improvements on PGI-C (58% vs 46%), with a similar trend observed for CGI-I (50% vs 46%; p=not significant). Motor complications (MDS-UPDRS-IV items 1–6 score ≥1) were reported in fewer patients in the OPC than the placebo group (5.5% vs 9.7%), with mean scores of 0.3 and 0.4 points, respectively. Frequency and types of adverse events were similar between the two groups; no dyskinesia was reported in either group.
Conclusion: Adjunct OPC significantly improved motor impairment in levodopa-treated PD patients without motor complications, with no dyskinesia reported as adverse event.
To cite this abstract in AMA style:
J. Ferreira, O. Rascol, F. Stocchi, A. Antonini, J. Moreira, G. Castilla-Fernández, J. Rocha, J. Holenz, W. Poewe. Opicapone as Add-on to Levodopa in Parkinson’s Patients without Motor Complications: Preliminary Data from EPSILON [abstract]. Mov Disord. 2024; 39 (suppl 1). https://www.mdsabstracts.org/abstract/opicapone-as-add-on-to-levodopa-in-parkinsons-patients-without-motor-complications-preliminary-data-from-epsilon/. Accessed June 14, 2025.« Back to 2024 International Congress
MDS Abstracts - https://www.mdsabstracts.org/abstract/opicapone-as-add-on-to-levodopa-in-parkinsons-patients-without-motor-complications-preliminary-data-from-epsilon/