However, at high istradefylline concentration, it causes locomotion depression akin to caffeine (which is a broad-spectrum adenosine receptor antagonist), and might do so by displacing adenosine, and working as a NAM towards D2R (instead of A2AR). History
It was first approved in Japan in 2013.The effectiveness of Nourianz in treating "off" episodes in patients with Parkinsons 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.

References
External links
"Istradefylline". Drug Information Portal. U.S. National Library of Medicine.
With RA, small joints are mostly affected in an inflammatory, destructive manner. This is not observed in IH. Rheumatoid factor, cyclic citrullinated peptide antibodies and antinuclear antibodies are usually negative in IH. Palindromic rheumatism. Like IH, palindromic rheumatism (PR) is also characterised by relapsing, short-episodes of sudden onset arthritis with no recognisable trigger. However, unlike PR, IH affects the knee almost exclusively and there is a predictable periodic, regularity of attacks, with laboratory tests during attacks being generally unremarkable. PR is also more likely to be associated with development of rheumatoid arthritis. Familial Mediterranean Fever. For some patients with FMF, episodes of knee or joint inflammation may be the only presenting symptom during an acute inflammatory episode. The MEFV gene mutations associated with FMF have been implicated in the pathogenesis of both palindromic rheumatism and IH. Other conditions for consideration (or exclusion) are other periodic arthropathies, crystal arthopathy, prepatellar bursitis (housemaids knee), pigmented villonodular synovitis, trauma and infectious causes. Treatment
No treatment has been found to be routinely effective. NSAIDs and COX-2 inhibitors are not generally helpful other than for general pain relief. They do not seem to help reduce effusions or prevent their occurrence. Low-dose colchicine (and some other ‘anti-rheumatic’ therapies e.g. hydroxychloroquine) have been used with some success. (Use of methotrexate and intramuscular gold have not been reported in the literature).