13. Aspartate transaminase (AST) level ≤ 2.5 x upper limit of normal (ULN) and alanine transaminase (ALT) ≤ 2.5 × upper limit of normal (ULN). For patients with liver metastases, AST ≤ 5 ULN, and AST ≤ 5 ULN may be enrolled if agreed upon by the investigator and medical monitor for the sponsor.