Issues have been raised concerning clinical relevance of HIV-1 proviral DNA genotypic resistance test (DNA GRT). To assess impact of DNA GRT on choice of antiretroviral therapy (ART) and subsequent virological outcome, we retrospectively reviewed decision-making and viral load (VL) evolution following DNA GRT performed in our center between January 2012 and December 2017, except those prescribed within the framework of a clinical trial. A total of 304 DNA GRTs were included, 185 (62%) performed in a context of virological success. Only 34% of tests were followed by ART change, more frequently in situation of virological success (39% vs. 26%, p = 0.02). In this situation, ART change guided by DNA GRT led to VL >20 copies/mL after 6 months in 5% of cases. In multivariate analysis, higher HIV DNA quantification (p = 0.01) was associated with occurrence of viremia. A higher nadir of CD4 count (p = 0.04) and a longer time with VL <20 copies/mL (p = 0.04) were independently associated with a lower risk of viremia. In situation of low-level viremia, ART change guided by DNA GRT led to VL <20 copies/mL after 6 months in 52% of cases, while decision to maintain the same treatment led to VL <20 copies/mL in 74% of cases. In multivariate analysis, longer time with VL >20 copies/mL (p = 0.02) was associated with persistence of virological replication. In conclusion, in situation of virological success, use of DNA GRT in addition to analysis of historical RNA GRT to guide ART optimization appears safe. Its prescription framework in situation of low-level viremia deserves to be better defined.
Keywords: HIV-1; genotypic resistance test; proviral DNA; virological failure; virological suppression.