Entacapone

Table of contents

• What is entacapone?
• How does entacapone work?
• Which conditions is entacapone used or studied for?
• How is entacapone given?
• What do the clinical trials show?
• What side effects are known?

What is entacapone?

Entacapone is a nitrocatechol-structured compound with a relative molecular mass of 305.29. It belongs to a class of medicines called catechol-O-methyltransferase (COMT) inhibitors.^[2] The substance is used in the treatment of Parkinson's disease as an adjunct to levodopa and carbidopa therapy.^[2] In the EU clinical trials registry, entacapone appears as part of a fixed combination product with levodopa and carbidopa monohydrate, under the product name Lecigon 20 mg/ml + 5 mg/ml + 20 mg/ml gel for intestinal use.^[1] Entacapone is already authorised as a medicine in Germany; the marketing authorisation holder is LobSor Pharmaceuticals AB.^[1]

How does entacapone work?

Entacapone is a selective and reversible inhibitor of the enzyme catechol-O-methyltransferase (COMT).^[2] In mammals, COMT is distributed throughout various organs, with the highest activities in the liver and kidney. COMT also occurs in the heart, lung, smooth and skeletal muscles, intestinal tract, reproductive organs, various glands, adipose tissue, skin, blood cells and neuronal tissues, especially in glial cells.^[2] COMT catalyses the transfer of a methyl group from S-adenosyl-L-methionine to the phenolic group of substrates that contain a catechol structure. Physiological substrates of COMT include dopa and catecholamines such as dopamine, norepinephrine and epinephrine.^[2] By blocking this enzyme, entacapone slows the breakdown of levodopa in the body, which helps more levodopa reach the brain.

Which conditions is entacapone used or studied for?

• Parkinson's disease — entacapone is used as an adjunct to levodopa and carbidopa therapy in this progressive neurological condition that affects movement.^[2] The authorised Phase 3 trial investigates a fixed combination intestinal gel containing entacapone for counteracting dopaminergic desensitisation and neuropsychiatric complications in Parkinson's disease.^[1]

How is entacapone given?

Entacapone is available as tablets containing 200 mg entacapone, taken by mouth.^[2] An oral suspension form, entacapone 200 mg/5 ml, is also listed as a prescribable product in the NHS dictionary of medicines.^[3] In the authorised clinical trial, entacapone is part of a fixed combination intestinal gel (Lecigon) given by intestinal use.^[1]

What do the clinical trials show?

One clinical trial involving entacapone is registered in the EU Clinical Trials Information System. The trial, INITIATE-LECIG, is a Phase 3 interventional study with a planned enrolment of 150 participants.^[1] Its status is Authorised, meaning it has received regulatory approval to proceed.^[1] The trial investigates the fixed combination product Lecigon (levodopa 20 mg/ml + carbidopa 5 mg/ml + entacapone 20 mg/ml) as an intestinal gel.^[1]

The primary outcome is to show superiority of Lecigon therapy compared to best medical treatment on hyperdopaminergic symptoms, measured using the Ardouin Behavioural Scale. Specifically, the trial looks at Section 1 (items 2 and 4) and Section 4 (all items) of this scale, comparing the pre-interventional baseline with the 6-month follow-up.^[1] The condition studied is Parkinson's disease.^[1]

What side effects are known?

The provided supplementary sources do not include a side-effect profile for entacapone. No adverse-effect data is therefore reported on this page.