Long Term Protease Inhibitor Monotherapy in a Two-Tiered HIV-1 Levels Design

Abstract

Treatment of choice in ART therapy for HIV-1 viremia remains an issue as all treatments interrupt HIV repopulation albeit at different reproductive points. The issue was addressed by grouping patients into two-tiered HIV level design of High >50,000 and Low <50,000 plasma cps/ml. The High group with 3 patients had combined class ART using NRTI plus NNRTI or PI regimens until viremia was reduced to <75 cps/ml and then PI alone. The Low group with 11 patients had PIMT regimen. CD4 T cell levels were monitored throughout. ART efficacy was assessed as total number of months of controlled (<75 cps/ml) viral infection level vs. number of months of uncontrolled levels of (>75 cps/ml). In that adherence/non-adherence to regimen is a confound, it was also assessed by rate of suppression: HIVj-HIVk/ HVj-HVn. In the High group, one patient attained long term controlled HIV viremia over 56 months vs. 3 months of uncontrolled viremia while the other two patients (21 vs. 25; 9 vs. 11) did not. Corresponding values in Group 2 ranged from 6 months to 139 months vs. <5 months A t-test for correlated means (with control for duration differences) showed significant difference: t=4.10, α=<0.01, df=10. Suppression rates, both within and across groups, were from: 0.99-1.0 of cps/ml. Accordingly, PI monotherapy can maintain long term viremia suppression for viral levels of <50,000 cps/ml and ART is operative within an inferred functionally closed boundary system as no host characterization including CD4 T cell level affected ART outcome.