Prevalence and factors associated with HIV-1 multi-drug resistance over the past two decades in the Italian ARCA database

• Despite successful antiretroviral therapy, patients with human immunodeficiency virus (HIV) could develop multi-class drug resistance (MDR) Data about the prevalence of HIV-MDR are scanty and results unclear A significant decline in over between 1998 2018 was observed Nowadays, still occurs, although at a lower rate Management infected by MDR viruses is critical issue HIV therapy (ART), can (MDR). This retrospective study aimed to explore HIV-1 past two decades focusing on its predictors. ART-experienced from least one plasma genotypic test (GRT) 2018, Antiviral Response Cohort Analysis database, were included this study. The temporal trend any class evaluated considering all GRTs. Prevalence predictors analysed consideration cumulative Among 15 628 isolates 6802 patients, decreased sharply 2010 (1998–2001: 78%; 2008–2010: 59%; P <0.001) then remained relatively constant approximately 50% 2011 proportion also stable (approximately 9%). By evaluating factors associated HIV-MDR, following found be increased risk multi-variate analysis: male gender; sexual vertical transmission; number previous protease inhibitors, nucleoside/nucleotide reverse transcriptase inhibitors (NRTIs) non-NRTIs; exposure integrase strand transfer enfuvirtide maraviroc; co-infection hepatitis B virus. In contrast, nadir CD4 cell count ?200 cells/mm 3 , starting first-line ART 2008 or later C HIV-MDR. conclusion, revealed that has been since despite dramatic decrease decades. present, rate, suggesting need for continuous surveillance accurate management HIV.