- Women of childbearing potential can only be included in the study if a pregnancy test is negative. Women of childbearing potential must agree to use adequate contraception when sexually active. 'Adequate contraception' is defined as any combination of at least 2 effective methods of birth control, of which at least one is a physical barrier (e.g. condoms with hormonal contraception or implants or combined oral contraceptives, certain intrauterine devices). Adequate contraception is required from the signing of the informed consent form up until 4 weeks after the last study drug administration