- All female subjects must be of non-childbearing potential. For the purposes of this study, non-childbearing potential is defined as pre-menopausal females with a documented tubal ligation or hysterectomy; or postmenopausal defined as 12 months of spontaneous amenorrhea [in questionable cases a blood sample with simultaneous follicle stimulating hormone (FSH) > 40 MlU/ml and estradiol < 40 pg/ml (<140 pmol/L) is confirmatory]. [Females on hormone replacement therapy (HRT) and whose menopausal status is in doubt will be required to use adequate contraception (hormonal or double barrier method of birth control [condom and occlusive cap (diaphragm or cervical/vault caps) with spermicidal foam, gel, film, cream, or suppository]; true abstinence) for the duration of the study dosing and for at least 12 weeks after the last treatment dose, if they wish to continue their HRT during the study. Otherwise, they must discontinue HRT to allow confirmation of post-menopausal status prior to study enrollment. For most forms of HRT, at least 2-4 weeks will elapse between the cessation of therapy and the blood draw; this interval depends on the type and dosage of HRT. Following confirmation of their post-menopausal status, they can resume use of HRT during the study without use of a contraceptive method].