Gout flare prophylaxis with colchicine or naproxen is required to be started prior to the first dose of study drug. Colchicine 0.6 mg once a day will begin at least 7 days prior to Day 1, or naproxen 250 mg twice daily will be started at least 48 hours prior to Day 1. For subjects who discontinue urate-lowering therapy, the required gout flare prophylaxis will begin at or before the cessation of the urate-lowering therapy.