Opicapone

Opicapone is a selective, reversible inhibitor of the enzyme catechol-O-methyltransferase (COMT) used as an adjunct to levodopa–carbidopa therapy in adults with Parkinson’s disease who experience motor fluctuations, such as wearing-off between doses. By inhibiting peripheral COMT, opicapone reduces the enzymatic breakdown of levodopa to 3-O-m-methyldopa, increasing and prolonging levodopa’s plasma levels and brain exposure. This helps smooth motor symptoms and extend the effect of levodopa.

Pharmacology and administration: Opicapone is taken orally as a capsule, typically at a dose of 50 mg once daily, in combination with levodopa-containing therapy. It is designed to be a long-acting COMT inhibitor, allowing once-daily dosing. It is generally advised to take it as prescribed, with or without food, alongside the levodopa regimen. After administration, opicapone is absorbed and metabolized in the body with elimination through typical hepatic and renal routes.

Indications and use: The drug is indicated for adults with Parkinson’s disease who experience end-of-dose motor fluctuations despite ongoing levodopa therapy. It is not intended as a standalone treatment.

Adverse effects and interactions: Common adverse effects include dyskinesia, nausea, constipation, diarrhea, dizziness, and orthostatic hypotension. Opicapone can interact with other dopaminergic medications and with MAO inhibitors, potentially increasing dopaminergic effects. Patients should inform clinicians of all medicines and any new symptoms, and monitor for alignment between levodopa dose adjustments and motor response.

Regulatory status: Opicapone is approved in several regions as an adjunct to levodopa therapy for Parkinson’s disease. Brand names and specific dosing guidelines may vary by country.