How relevant is the HIV low level viremia and how is its management changing in the era of modern ART? A large cohort analysis

Background: It is still unclear what might be the best management of people living with HIV (PLWHIV) with low level viremia (LLV) despite being on antiretroviral treatment (ART). Objectives: Aim of our study is to describe the clinical management of PLWHIV with LLV followed in a large cohort. Study design: Retrospective cohort study. Results: We included 1607 adult patients over a three-year period (2015–2017). Follow up continued until June, 30th 2019 or last available visit. We observed a low incidence of LLV (0.9 % in 2015, 0.7 % in 2016 and 0.4 % in 2017), with a total of 21 patients with persistent LLV (pLLV), i.e. two consecutive HIV-RNA determinations of 50–500 copies/ml after at least 4 months of viral suppression. Among them, 12 had low compliance to treatment. Genotype resistance test (GRT) was performed in 14 patients and demonstrated at least one resistance mutation in 85.7 %. We described three categories of patients with pLLV: i) those whose ART regimen was not adequate based on GRT; ii) those with presumed suboptimal drug exposure, consequence of low adherence and/or drug-drug interactions and iii) those in which pLLV remained unexplained. For the first two categories, optimization or intensification of ART regimen led to viral suppression in >80 % of patients. We observed only 2 (9.5 %) virological failures and 1 (4.8 %) persistence of LLV in patients who did not switch ART. Conclusions: In our cohort, the rate of LLV showed a decline in most recent years. Adherence and previous GRT should be carefully considered with the aim of further reducing the phenomenon