 20. Sexually active pre-menopausal female subjects and female partners of male subjects must use adequate contraceptive measures, while on study and for 50 days after the last dose of study drug. Sexually active male subjects must use adequate contraceptive measures, while on study for at least 90 days after the last dose of drug. All fertile male and female subjects and their partners must agree to use a highly effective method of contraception including their partner. Effective birth control includes a IUD plus one barrier method; or b 2 barrier methods. Effective barrier methods are male or female condoms, diaphragms, and spermicides creams or gels that contain a chemical to kill sperm. Note: Oral, implantable, or injectable contraceptives may be affected by cytochrome P450 interactions, and are not considered effective for this study. 