6. Estimated creatinine clearance (for patients > 12 years) greater than 50.0 mL/minute (using the Cockcroft-Gault formula and actual body weight); for pediatric patients (> 1 year to 12 years), Glomerular Filtration Rate (GFR) estimated by the updated Schwartz formula ≥ 90.0 mL/min/1.73 m^2. If the estimated creatinine clearance is < 90 mL/min/1.73 m^2, then renal function must be measured by 24-hour creatinine clearance or nuclear GFR, and must be > 70.0 mL/min/1.73 m^2.