- Females of childbearing potential (FCBP) must have a negative urine pregnancy test at screening (Visit 1). In addition, sexually active FCBP must agree to use TWO of the following adequate forms of contraception while on study medication: oral, injectable, or implantable hormonal contraceptives; tubal ligation; intrauterine device; barrier contraceptive with spermicide; or vasectomized partner while on study. A FCBP must agree to have pregnancy tests every 4 weeks while on study.