<qa>  What is a negative pregnancy test at Screening and BaselineDay 1?5. Women of childbearing potential must be using at least one form of medically acceptable contraception i.e. either oral, topical, implanted hormonal contraceptives, or an intrauterine device or two barrier methods; have a negative pregnancy test at Screening and BaselineDay 1 and agree to use reliable methods of contraception until at least 24-hours after the last dose of study drug. Women who are surgically sterile i.e. hysterectomy, bilateral oophorectomy, or tubal ligation or those who are post-menopausal for at least 2 years are not considered to be of childbearing potential. Men who are not sterile i.e. have not had a vasectomy must also agree to use contraception until at least 24-hours after the last dose of study drug. 