Coadministration of ombitasvir/paritaprevir/r + dasabuvir (25/150/100 + 400 mg, once daily) with emtricitabine/tenofovir-DF (200/300 mg once daily) was studied in 18 healthy volunteers. (Note, the 400 mg dose of dasabuvir used in this study provides equivalent exposures to that of the 250-mg marketed dose of dasabuvir.) Emtricitabine Cmax, AUC and Ctrough increased by 5%, 7% and 9%, respectively. Tenofovir Cmax, AUC and Ctrough increased by7%, 13% and 24%, respectively. Paritaprevir Cmax and AUC decreased by 32% and 16% but Ctrough increased by 6%. Pharmacokinetic parameters for ombitasvir, ritonavir and dasabuvir were not affected (≤20% change). The authors conclude that combining ombitasvir/paritaprevir/r + dasabuvir with emtricitabine/tenofovir-DF is safe and no dose adjustment is required.