- Adequate hepatic function defined by total bilirubin level less than or equal to 1.5 times the upper limit of normal (ULN), and aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels less than or equal to 2.5 x ULN; or, for subjects with documented metastatic disease to the liver, AST and ALT levels less than or equal to 5 x ULN.