6. Inclusion Criteria 5) continued: 6) Serum creatinine CL>40 mL/min by the Cockcroft-Gault formula (Cockcroft and Gault 1976) or by 24-hour urine collection for determination of creatinine clearance: Males: Creatinine (mL/min) Clearance (CL) = Weight (kg) x (140 minus Age) / 72 x serum creatinine (mg/dL)