1. Alanine aminotransferase (ALT) or aspartate aminotransferase (AST) > 2.0 × the upper limit of normal (ULN) at screening. (Subjects with an isolated AST elevation of any magnitude, or a ratio of AST:ALT > 1.5 should be interviewed regarding use of alcohol, have levels repeated and participation in the study should be discussed with the medical monitor.)