You will also have blood drawn (less than 1 teaspoon each) for antibody testing at different time points throughout this study. Antibody testing is a method to check for proteins (IgG) made by your body that show that your body is reacting to rasburicase. You will have at least 5 samples drawn. Your blood will be drawn on Day 1 before your dose of rasburicase and then on Day 14, Day 35, and at 3 and 6 months after your dose of the study drug.