- Use of strong CYP3A4 inhibitors (eg, indinavir, nelfinavir, ritonavir, clarithromycin, itraconazole, ketoconazole, nefazodone, saquinavir, suboxone, telithromycin, atazanavir) and strong CYP3A4 inducers (eg, carbamazepine, rifampin, phenytoin and St. John's wort), within 28 days prior to study drug administration (Day 1).