Clinical Outcomes Associated With Once-Daily Ritonavir-Boosted Darunavir Plus Tenofovir/Emtricitabine in HIV-Infected Patients Harboring at Minimum a M184V/I Resistance Mutation

Background: Limited data exist on the use of a boosted protease inhibitor plus <2 active nucleoside/nucleotide reverse transcriptase inhibitors without use of additional classes of antiretroviral (ARV) therapy in treatment-experienced patients with background resistance. Objective: To evaluate clinical outcomes in HIV-infected patients harboring single- or multiclass resistant virus and receiving once-daily tenofovir/emtricitabine (TDF/FTC) plus darunavir/ritonavir (DRV/r) administered for >24 weeks. Methods: This was a single-center chart review of HIV-infected patients receiving daily TDF/FTC plus DRV/r and identified with resistant virus (including, but not limited to, an M184V/I). The primary outcome was HIV viral load (VL) <200 copies/mL (cp/mL) at last measurement. Additional end points included virological rebound (VR), resuppression, or failure (VF); VL <40 cp/mL at last measurement; and development of additional mutations. Results: Of 171 eligible patients, 32 were included in the study and received DRV 800 mg/r 100 mg daily with fixed-combination TDF/FTC. All patients had a baseline M184V/I mutation, with 10 (31%) having resistance to TDF; 27 (84%) achieved a VL <200 cp/mL, and 25(78%) had a VL <200 cp/mL at the last reading; 22 (69%) achieved a VL <40 cp/mL. VF occurred in 6/32 (19%) patients and VR in 1/32 (3%) patients. Conclusion and Relevance: Although providing a regimen containing ≤2 active drugs, the use of once-daily DRV/r plus TDF/FTC in treatment-experienced patients with single-/multiclass resistant virus resulted in virological suppression in more than three-fourths of patients. These retrospective data suggest that despite the presence of an M184V/I, this combination may be an option in patients seeking a once-daily ARV therapy to improve adherence.