10. Women of child-bearing potential not employing an effective method of birth control. Two birth control methods must be used throughout the trial and one month after the last dose of study drug (e.g. condom with spermicidal jelly, foam suppository or film; diaphragm with spermicide; male condom and diaphragm with spermicide). Contraceptives that are affected by cytochrome P450 interactions (e.g. oral, implantable, injectable, or intrauterine hormonal contraceptives) are not considered effective for this study. Women of child-bearing potential, defined as sexually mature women who have not undergone a hysterectomy or who have not been naturally postmenopausal for at least 12 consecutive months (i.e., who has had menses any time in the preceding 12 consecutive months), must have a negative serum pregnancy test ≤ 7 days prior to starting study drug.