Continued Slow Decay of the Residual Plasma Viremia Level in HIV-1-Infected Adults Receiving Long-term Antiretroviral Therapy

Abstract

We measured plasma human immunodeficiency virus type 1 (HIV-1) RNA levels by means of single-copy assay in 334 participants receiving virologically suppressive antiretroviral therapy (ART). A residual viremia load of ≥1 copy/mL after 4 years of ART was predicted by a higher pre-ART HIV-1 RNA level, higher CD8(+) T-cell count during treatment, and a lower ratio of CD4+ T cells to CD8+ T cells during treatment but not by initial ART regimen. In a longitudinal subset of 64 individuals, continued decay of the plasma HIV-1 RNA level was observed, with an average annual decrease of 6% and an estimated half-life of 11.5 years. In contrast to prior reports, the persistent viremia level continues to slowly decline during years 4-12 of suppressive ART.

Clinical trials registration: NCT00001137.

Keywords: CD4/CD8 ratio; HIV/AIDS; residual viremia; single-copy assay; viral decay.

Figure 1.

Distribution of human immunodeficiency virus type 1 (HIV-1) RNA levels determined by a single-copy assay (SCA) for the longitudinal cohort of 64 individuals, by time after initiation of suppressive antiretroviral therapy (ART). A, SCA findings for all participants. B, SCA findings for the subset of 27 participants with an HIV-1 RNA load of ≥1 copy/mL at the 4-year (192-week) time point after ART initiation.