Emtricitabine/Tenofovir-DF (FTC/TDF, PrEP)
Quality of Evidence: Very Low
Coadministration has not been studied. Based on metabolism and clearance a clinically significant interaction is unlikely with emtricitabine as it is primarily renally excreted and darunavir/cobicistat is unlikely to inhibit OCTs at clinically relevant concentrations. However, darunavir/cobicistat is expected to increase tenofovir plasma concentrations (inhibition of P-gp). Darunavir/cobicistat and tenofovir disoproxil fumarate can be used without dose adjustments, but monitoring of renal function may be indicated when darunavir/cobicistat is given in combination with tenofovir disoproxil fumarate, particularly in patients with underlying systemic or renal disease, or in patients taking nephrotoxic agents.