- Patients currently taking strong inhibitors of the CYP3A4 family (e.g., ketoconazole, itraconazole, clarithromycin, atazanavir, indinavir, nefazodone, nelfinavir, ritonavir, saquinavir, telithromycin, voriconazole) AND inducers of the CYP3A4 family (e.g., dexamethasone, phenytoin, carbamazepine, rifampin, rifabutin, rifapentin, phenobarbital, St. John's Wort) because of possible pharmacokinetic interactions with sunitinib. Patients who are no longer taking strong CYP3A4 inhibitors and/or inducers are ineligible unless they have discontinued use 4 weeks prior to beginning therapy.