- For FEMALE SUBJECT OF CHILDBEARING POTENTIAL, must have had a regular menstrual cycle prior to study entry (a female is considered of childbearing potential unless she is postmenopausal, without a uterus and/or both ovaries, or has had a bilateral tubal ligation) and is willing to use an acceptable form of birth control during the entire course of the study [i.e., acceptable methods of birth control are oral contraceptives, contraceptive patches/rings/implants Norplant®, Depo-Provera®, double-barrier methods (e.g. condoms and spermicide), abstinence and vasectomies of partner with a documented second acceptable method of birth control should the subject become sexually active]. All systemic birth control measures must be in consistent use at least 30 days prior to study participation. Postmenopausal is defined as having the last menstrual cycle in at least 12 months