We analyzed patients receiving standard regimens with at least 1 VL measurement below the limit of quantification (BLQ) in their treatment history. The first VL measurement after 6 months of unmodified cART served as baseline VL for the subsequent analyses of the time to reach single VL levels of ≥200, ≥400, and ≥1000 copies/mL. Roche TaqMan 2.0 was used to quantify human immunodeficiency virus-1 ribonucleic acid. Factors associated with VF were determined by Cox proportional hazards models.In this study, we present data from a cohort of well defined human immunodeficiency virus (HIV)-infected patients on unmodified cART with standard regimens over a recent period of more than 6 months in Austria. The aim of the study was to evaluate the impact of LLV, measured by TaqMan 2.0 assay, and other factors that could increase risk of VF. Virological failure was defined as HIV ribonucleic acid (RNA) levels of ≥200, ≥400, and ≥1000 copies/mL.