5. Female subjects of childbearing potential, defined as not surgically sterile or at least 2 years postmenopausal, must agree to use one of the following forms of contraception for the duration of the study: hormonal (oral, implant, or injection) begun >30 days prior to screening, barrier (condom, diaphragm with spermicide), intrauterine device (IUD), or vasectomized partner (6 months minimum).