Predictors of incomplete viral response and virologic failure in patients with acute and early HIV infection. Results of Italian Network of ACuTe HIV InfectiON (INACTION) cohort.

Abstract

The aim of this study was to evaluate the factors that can influence an incomplete viral response (IVR) after acute and early HIV infection (AEHI). This was a retrospective, observational study including patients with AEHI (Fiebig stages I-V) diagnosed between January 2008 and December 2014 at 20 Italian centres. IVR was defined by: (1) viral blip (51-1000HIV-1 RNA copies/mL after achievement of <50HIV-1 RNAcopies/mL); (2) virologic failure [>1000copies/mL after achievement of <200copies/mL, or ≥200copies/mL after 24weeks on an antiretroviral therapy (ART)]; (3) suboptimal viral response (>50copies/mL after 48weeks on ART or two consecutive HIV-1 RNA levels with ascending trend during ART). Cox regression analysis was used to calculate the hazard ratios (HRs) and 95% confidence intervals (95% CIs) for IVR. In all, 263 patients were studied, 227 (86%) males, with a median [interquartile range (IQR)] age of 38 (30-46) years. During a median follow-up of 13.0 (5.7-31.1) months, 38 (14.4%) had IVR. The presence of central nervous system (CNS) symptoms was linked to a higher risk of IVR (HR = 4.70, 95% CI: 1.56-14.17), while a higher CD4/CD8 cell count ratio (HR = 0.13, 95% CI: 0.03-0.51 for each point increase) and first-line ART with three-drug regimens recommended by current guidelines (HR = 0.40, 95% CI: 0.18-0.91 compared with other regimens including four or five drugs, older drugs or non-standard backbones) were protective against IVR. Patients with lower CD4/CD8 ratio and CNS symptoms could be at a higher risk of IVR after AEHI. The use of recommended ART may be relevant for improving short-term viral efficacy in this group of patients.