- A female subject of childbearing potential must have been using a medically acceptable, adequate form of birth control. This includes: 1) hormonal contraceptives as prescribed by a physician (oral combined, hormonal implant); 2) medically prescribed intra-uterine device (IUD); 3) condom in combination with a spermicide (double barrier method); 4) monogamous relationship with a male partner who has had a vasectomy. The subject must have started this birth control method at least 3 months prior to Screening (with the exception of condom in combination with spermicide), and must agree to continue its use for the duration of the study. A female subject of childbearing potential who is not currently sexually active must agree and consent to using a medically acceptable birth control method should she become sexually active during the course of this study. Women who have been surgically sterilized or are at least 1 year postmenopausal are not considered to be of childbearing potential. A female subject of childbearing potential must have a negative serum pregnancy test at Screening in order to be considered eligible for enrollment.