Istradefylline


Istradefylline, sold under the brand name Nourianz, is a medication used as an add-on treatment to levodopa/carbidopa in adults with Parkinson's disease experiencing "off" episodes. Istradefylline reduces "off" periods resulting from long-term treatment with the antiparkinson drug levodopa. An "off" episode is a time when a patient's medications are not working well, causing an increase in PD symptoms, such as tremor and difficulty walking.
Relatively common side effects include involuntary muscle movements, constipation, hallucinations, dizziness and, much like its parent molecule caffeine, nausea and sleeplessness. It is a selective antagonist at the A2A receptor.

History

It was first approved in Japan in 2013.
The effectiveness of Nourianz in treating "off" episodes in patients with Parkinson's disease who are already being treated with levodopa/carbidopa was shown in four 12-week placebo-controlled clinical studies that included a total of 1,143 participants. In all four studies, people treated with Nourianz experienced a statistically significant decrease from baseline in daily "off" time compared to patients receiving a placebo.
It was approved for medical use in the United States in 2019. and approval was granted to Kyowa Kirin, Inc.