- Patients who are currently receiving treatment (within 5 days prior to starting study drug) with agents that are metabolized predominantly through CYP3A4 and that have a narrow therapeutic window. Agents including vitamins, supplements, and herbal supplements that are either (i) metabolized solely through CYP3A4/5, CYP1A2 or BSEP and have a narrow therapeutic window or (ii) are strong inhibitors of CYP3A4/5, CYP1A2 or BSEP. Agents that are known strong inducers or inhibitors CYP3A4 are prohibited. Patients must avoid consumption of grapefruit, Seville oranges or products containing the juice of each during the entire study and for 7 days before the first dose.