- Note: A female patient is considered to be of childbearing potential unless she has had a hysterectomy, is at least one year postmenopausal or has undergone tubal ligation. For the purposes of this study, adequate birth control includes at least one medically approved and highly effective method of birth control, defined as those which result in a low failure rate (i.e., < 1% per year) when used consistently and correctly, such as implants, injectables and oral contraceptives combined with the use of condoms. Only male patients whose vasectomy has been confirmed by semen analysis at least 3 months after the vasectomy are allowed not to use acceptable contraceptive methods.