Objectives: To study the impact of protease inhibitor monotherapy on the HIV-1 blood reservoir in 72 antiretroviral-naive patients.
Patients and methods: This was evaluated for 72 antiretroviral-naive patients included in the on-treatment analysis of the MONARK trial; 46 patients receiving lopinavir/ritonavir monotherapy and 26 patients receiving a triple therapy. HIV-DNA was quantified in whole blood, using real-time PCR.
Results: The decrease in HIV-DNA after 48 weeks of lopinavir/ritonavir monotherapy was similar to the decrease observed with triple therapy including lopinavir/ritonavir (-0.77 versus -0.69 log copies/10(6) leucocytes, respectively; P = 0.91). The HIV-DNA decrease was also similar in patients with a virological response in both arms (-0.69 versus -0.69 log copies/10(6) leucocytes, respectively). Interestingly, non-responders had a significantly higher baseline HIV-DNA load than responders in the monotherapy arm; 3.16 versus 2.86 log copies/10(6) leucocytes, respectively (P = 0.05).
Conclusions: The MONARK data indicate that a lopinavir/ritonavir monotherapy regimen is potent against HIV blood reservoirs in antiretroviral-naive patients after 1 year of treatment, in comparison with a standard-of-care highly active antiretroviral therapy. This impact should be evaluated with other boosted protease inhibitor monotherapies.