Effect of Febuxostat on Renal Function in Patients With Gout and Moderate to Severe Renal Impairment

Gout is caused by high levels of uric acid in the body, and is associated with a broad range
of conditions including heart disease, chronic kidney disease and high blood pressure.
Hyperuricemia, which is defined as an elevation in serum urate levels, develops into gout
when urate crystals form in the body and settle in joints and other organs.

Approximately 40-60% of patients with hyperuricemia and gout have some degree of renal
impairment. Hyperuricemia has long been associated with renal disease, and chronic
hyperuricemia as seen in gout can lead to deposition of urate crystals resulting in
diminished renal function.

This study will evaluate the effect of febuxostat on the renal function of subjects with
hyperuricemia and gout and moderate to severe renal impairment.

All subjects must have an average sitting blood pressure measurement less than 160 mmHg
systolic and less than 95 mmHg diastolic. All subjects must meet the American Rheumatism
Association (ARA) diagnostic criteria for gout. Subjects are expected to return to the site
for approximately 10 visits.