- Males or females ≥ 18 years of age. Pre-menopausal females (with the exception of those who are surgically sterile) must have a negative pregnancy test at screening; those who are sexually active must practice a highly effective method of birth control for at least 4 weeks prior to study start, and must be willing to continue contraception until at least 4 weeks after the last dose of study drug. A highly effective method of birth control is defined as one that results in a low failure rate (i.e., less than 1% per year) when used consistently and correctly such as implants, injectables, combined oral contraceptives, some intrauterine devices (IUDs), sexual abstinence (only acceptable if practiced as a life-style and not acceptable if one who is sexually active practices abstinence only for the duration of the study) or vasectomized partner;