 - All participants must agree not to participate in the conception process e.g., active attempt to become pregnant or to impregnate, sperm donation, or in vitro fertilization. If participating in sexual activity that could lead to pregnancy, the participantpartner must use at least two reliable forms of contraceptives e.g., condoms, with or without a spermicidal agent; a diaphragm or cervical cap with spermicide; an IUD; hormone-based contraception, with at least one being a barrier method, during the study. 