8. Pregnant or breastfeeding females or males and females with childbearing potential must be willing to use an adequate method of birth control (intrauterine device, vasectomy of female subjects' male partner, contraceptive rod implanted into the skin, combination method - (requires use of two of the following) diaphragm with spermicide, cervical cap spermicide, contraceptive sponge, condom, hormonal contraceptive)