: This prospective, open-label nonrandomized controlled trial evaluated the efficacy, safety, and pharmacokinetics of substituting nevirapine/emtricitabine/tenofovir for rilpivirine/emtricitabine/tenofovir in 50 suppressed HIV-1 switchers. One hundred thirty-nine nonswitchers remained on nevirapine as controls. Week 12 HIV-1 RNA was <50 copies per milliliter in 92.0% of switchers and was <50 copies per milliliter at week 24 in 88.0% of switchers and 90.6% of nonswitchers (difference 2.6%, 95% confidence interval: -7.6% to 12.8%). Week 3 geometric mean nevirapine concentration was undetectable and week 1 geometric mean rilpivirine concentration (0.083 mg/L) was comparable with phase 3 trial (P = 0.747). Substituting nevirapine for rilpivirine resulted in ongoing virological suppression and did not have clinically relevant pharmacokinetic effects by cytochrome P450 interactions.