BackgroundNon-structural 5A protein (NS5A) resistance-associated substitutions (RASs) have been identified in patients infected with hepatitis C virus (HCV), even prior to exposure to direct-acting antiviral agents (DAAs). Selection for these variants occurs rapidly during treatment and, in some cases, leads to antiviral treatment failure. DAAs are currently the standard of care for hepatitis C treatment in many parts of the world. Nevertheless, in Brazil, the prevalence of pre-existing NS5A RASs is largely unknown. In this study, we evaluated the frequency of naturally occurring NS5A RASs in Brazilian patients infected with HCV as either a monoinfection or coinfection with human immunodeficiency virus (HIV).MethodsDirect Sanger sequencing of the NS5A region was performed in 257 DAA-naïve patients chronically infected with HCV (156 monoinfected with HCV and 101 coinfected with HIV/HCV).ResultsThe frequencies of specific RASs in monoinfected patients were 14.6% for HCV GT-1a (M28 V and Q30H/R), 6.0% for GT-1b (L31F/V and Y93H), and 22.6% for GT-3a (A30K and Y93H). For HIV/HCV-coinfected patients, the frequencies of RAS were 3.9% for GT-1a (M28 T and Q30H/R), and 11.1% for GT-1b (Y93H); no RASs were found in GT-3a sequences.ConclusionsSubstitutions that may confer resistance to NS5A inhibitors exist at baseline in Brazilian DAA-naïve patients infected with HCV GT-1a, −1b, and -3a. Standardization of RAS definitions is needed to improve resistance analyses and to facilitate comparisons of substitutions reported across studies worldwide. Therapeutic strategies should be optimized to efficiently prevent DAA treatment failure due to selection for RASs, especially in difficult-to-cure patients.

In Brazil, the circulation of hepatitis E virus (HEV) has been demonstrated in distinct groups of individuals and some animals, but its prevalence among individuals with human immunodeficiency virus (HIV) infection is unknown. This study aimed to assess the frequency of serological and molecular HEV markers in individuals infected with HIV from São Paulo, Brazil. Serum and plasma samples of 354 HIV-infected patients collected between 2007 and 2013 were included. All samples were tested for anti-HEV IgG and IgM antibodies and HEV RNA. Anti-HEV IgG and IgM antibodies were detected in 10.7% (38/354) and 1.4% (5/354) of the samples, respectively. Both antibodies were detected simultaneously in only two samples. HEV RNA was not detected in any sample. There was no significant correlation of anti-HEV serological status (positivity to anti-HEV IgG and/or IgM) with sex, age, CD4 T cell count, HIV viral load, antiretroviral therapy, liver enzyme levels, or coinfection with hepatitis B virus and/or hepatitis C virus. Our study provides serological evidence of past and recent HEV infections in HIV-infected patients from São Paulo, Brazil. However, the occurrence of ongoing HEV infection appears be a rare event in this population.

Resistance-associated variants (RAVs) represent a challenge to the success of new HCV therapies. The aim of this study was to describe the prevalence of naturally occurring NS5B RAVs in Brazilian direct acting antivirals (DAA)-naïve patients infected with HCV genotype 1, or co-infected with HIV. Patient enrollment and sample collection were performed between 2011 and 2013. Using Sanger-based sequencing, 244 sequences were obtained. RAVs detected in HCV-1a sequences were V321A (1.6 %), M414V (1.3 %), A421V (21.4-23.7 %), A421G (1.3 %) and Y448H (1.3 %); and in HCV-1b sequences were L159F (16.1 %), C316N (7.1-16.3 %) and A421V (3.2-6.3 %). Understanding the real RAVs scenario in patients is fundamental to establishing the most effective therapeutic strategy and in minimizing the risks for their selection.

Baseline HCV NS3 amino acid substitutions identified herein are considered mostly natural polymorphisms with no clinical impact on PI-based therapy. The identified resistance mutations may be associated with low-level resistance to PIs in vitro. Q80K substitution seems to be a rare event in Brazil. HIV coinfection was not associated with a greater frequency of such substitutions in the studied sample.

In a hepatitis C virus (HCV)/HIV-positive Brazilian cohort, evaluate the safety and efficacy of HCV DAAs, the frequency of resistance substitutions in the HCV NS5A and NS5B genes and identify predictors of treatment failure. Retrospective multicenter study of HCV/HIV patients treated with sofosbuvir (SOF)-based regimens at 10 reference centers in Brazil. Clinical and virological data were collected. Genetic diversity in the NS5A and NS5B genes was assessed by direct nucleotide sequencing. The primary outcome was sustained virological response (SVR) 12 weeks after DAA completion. Of 643 HCV/HIV patients analyzed, 74.7% were male, median CD4+ T cell count was 617 cells/mm 3 , 90% had an undetectable HIV viral load. HCV genotype 1 was detected in 80.2%, and 60% were taking at least 1 medication other than antiretroviral drugs during their DAA therapy. Cirrhosis was present in 42%. An SOF/daclatasvir (DCV) regimen was used in most patients (98%). The frequency of NS5A polymorphisms associated with clinically relevant resistance to DCV was 2%; no relevant NS5B variants were identified. The SVR12 rate was 92.8% in an intention to treat (ITT) analysis and 96% in a modified ITT (m-ITT) analysis. AE occurred in 1.6% of patients. By multivariate analysis, therapeutic failure was associated, in the m-ITT analysis, with concomitant use of anticonvulsant drugs ( P = .001), age ( P = .04), and female gender ( P = .04). SOF/DCV regimens were associated with a high SVR rate in an HCV/HIV population. The use of concurrent anticonvulsant drugs and DAAs decreases the chances of achieving an SVR.