 - Female subjects who are of child-bearing potential must have a negative pregnancy test at the Screening Visit and agree to utilize contraceptive methods during participation in the study and for at least six months following the last dose of 506U78 Injection. Female subjects may be defined as of non-child-bearing potential if they are physiologically incapable of becoming pregnant, including any female who is post-menopausal. For purposes of this study, postmenopausal is defined as one year without menses. 