On August 27, 2019, the FDA approved Kyowa Kirin’s
NOURIANZ™ (istradefylline), an adjunct therapy “used to treat 'off' episodes in patients with Parkinson’s disease (PD).” Key findings from the FDA’s
Clinical Review: The product was approved based on four pivotal controlled trials: studies
6002-US-005 (NCT00456586; n=180),
6002-US-013 (NCT00199407; n=230),
6002-0608 (NCT00455507; n=363), and
6002-009 (NCT00955526; n=373). Study 6002-US-005 was conducted in the U.S. and Canada, study 6002-US-013 in the U.S., and studies 6002-0608 and 6002-009 in Japan. In addition, the
safety database includes all patients from 24 trials (n=4,768) and
postmarketing exposure in Japan (n=56,000). Impulse control disorders were observed in one patient in the controlled trials, as well as in the Japanese postmarketing setting.
Purpose The primary purpose of the RWD study was to support the safety profile for istradefylline.
What was done The applicant submitted an analysis of postmarketing data from approximately 56,000 Japanese patients as part of its application materials. That information is not publicly available, but contained information current through October 31, 2018. Apart from the postmarketing data, the safety database included 4,768 subjects from 24 clinical trials (eight Phase II/III placebo-controlled trials, five Phase III open-label extension studies, five pilot Phase II placebo-controlled trials, and six placebo-controlled trials for monotherapy).
Outcome The review of the postmarketing data noted two instances of impulse control disorders, three cases of suicidal behavior, and two cases of sepsis. These data points did not result in new safety signals for the product. The postmarket data was included in the prescribing information for istradefylline.
