- Subjects must have adequate hepatic function, as defined by a bilirubin level of ≤ 1.5 times the upper limit of the normal range (ULN) and an aspartate aminotransferase (AST) or alanine aminotransferase (ALT) level of ≤ 3 times the ULN (or ≤ 5 times the ULN if liver metastases are present).