- Use of prescription or nonprescription drugs, vitamins and dietary supplements, within 7 days or 5 half-lives (whichever is longer) of the first dose of study medication. Herbal supplements and hormonal methods of contraception (including oral and transdermal contraceptives, injectable progesterone, progestin subdermal implants, progesterone-releasing IUDs, postcoital contraceptive methods) and hormone replacement therapy must be discontinued 28 days prior to the first dose of study medication. Depo-Provera® must be discontinued at least 6 months prior to the first dose of study medication. As an exception, acetaminophen/paracetamol may be used at doses of ≤ 2 grams/day. Limited use of non-prescription medications that are not believed to affect subject safety or the overall results of the study may be permitted on a case-by-case basis following approval by the sponsor.