Serum aspartate aminotransferase (AST) ≥2.0 x upper limits of normal (ULN). Serum alanine aminotransferase (ALT) ≥2.0 x ULN. Alkaline phosphatase and bilirubin ≥1.5 x ULN (isolated bilirubin ≥1.5 ULN is acceptable if bilirubin is fractionated and direct bilirubin <35%.