1.- Have a negative serum pregnancy test at screening 2.- Are not breastfeeding 3.- Do not plan to become pregnant during the study 4.- Have had a hysterectomy or tubal ligation at least 6 months prior to signing the informed consent form or 5.- Have been postmenopausal for at least 1 year or 6. - If they are of childbearing potential and will practice one of the following methods of birth control throughout the study: oral, patch, injectable, or implantable hormone contraception, intrauterine device, diaphragm plus spermicide or female condom plus spermicide. Abstinence, partner's vasectomy are not acceptable methods of contraception.