- Patients with an estimated (Cockroft and Gault equation) to the power of 40 or calculated baseline creatinine clearance of 30-50 mL/min should have the starting dose of capecitabine reduced to 750 mg/m2 BID X 14 days; the dose of PHY906 remains unchanged. Patients with a baseline creatinine clearance of less than 30 mL/min should not be enrolled in this trial.