Efficacy

Ongentys (Opicapone) Efficacy in Parkinson's Disease

Ongentys (opicapone) is a medication that is used as an adjunctive treatment to levodopa/carbidopa in adults with Parkinson's disease who are experiencing "off" episodes. An "off" episode is a period when the patient's medications are not working well, causing an increase in Parkinson's symptoms such as tremor and difficulty moving. Opicapone works by inhibiting an enzyme called catechol-O-methyltransferase (COMT), which breaks down dopamine in the brain. By inhibiting COMT, opicapone extends the effect of levodopa, increasing the levels of dopamine in the brain and thereby helping to reduce the amount of time patients spend in the "off" state.

Clinical trials have demonstrated the efficacy of opicapone in reducing "off" time. The pivotal phase III studies (BIPARK-I and BIPARK-II) showed that opicapone, when added to levodopa therapy, significantly reduced "off" time compared to placebo. Patients treated with opicapone experienced an improvement in motor symptoms and were able to maintain better control over their Parkinson's symptoms throughout the day. The reduction in "off" time was accompanied by an increase in "on" time without troublesome dyskinesia, which is an important consideration in Parkinson's disease management.

Nourianz/Nouriast (Istradefylline) Efficacy in Parkinson's Disease

Nourianz (istradefylline) in the United States, also known as Nouriast in Japan, is another medication used as an adjunctive treatment to levodopa/carbidopa in adult patients with Parkinson's disease experiencing "off" episodes. Istradefylline is an adenosine A2A receptor antagonist. By blocking these receptors, istradefylline is thought to modulate the neurotransmitters in the brain that affect motor function, without directly increasing dopamine levels. This mechanism of action is distinct from that of opicapone and other Parkinson's disease medications.

The efficacy of istradefylline has been established in several clinical trials. These studies have shown that istradefylline, when added to a stable dose of levodopa, can lead to a reduction in "off" time for patients with Parkinson's disease. The reduction in "off" time was statistically significant when compared to placebo, indicating that istradefylline is an effective treatment option for managing "off" episodes in Parkinson's disease. Patients treated with istradefylline also saw improvements in motor function during "on" periods, although the medication may be associated with an increased risk of dyskinesia.