Note: this interaction was studied using a darunavir/ritonavir dose lower than that licensed. Coadministration of tenofovir-DF (300 mg once daily) and darunavir/ritonavir (300/100 mg twice daily) increased darunavir Cmax (16%), AUC (21%) and Cmin (24%). Tenofovir Cmax, AUC and Cmin increased by 24%, 22% and 37%, respectively. No adjustments to the licensed doses are required. A higher risk of renal impairment has been reported in patients receiving tenofovir-DF and a ritonavir or cobicistat boosted protease inhibitor. Close monitoring of renal function and for tenofovir-associated adverse reactions is required in these patients.