Resistance test guided retreatment of HCV infected patients with a previous failure to a NS5A inhibitor-containing regimen: the Italian Vironet C real life experience

Previous article in issueNext article in issue Introduction: There is a limited documentation about the retreatment of patients failing a recommended NS5A-containing regimen in Italy. Materials & methods: Within the VIRONET-C network, 386 NS5A-failing patients infected with different HCV-genotypes (GT) (GT1a/1b/2a-c/3a-b-g-h/4a-d-n-o-v=93/124/19/112/38) were analyzed. Retreatment of 105 failures was investigated. HCV-resistance-test was performed by Sanger-sequencing. Results: Failures following seven different NS5A-containing regimens were studied: 3D/2D (paritaprevir/ombitasvir ± dasabuvir) ± ribavirin (N = 72/4), daclatasvir/ledipasvir/velpatasvir + sofosbuvir ± ribavirin (N = 105/13…

Frequent NS5A and multiclass resistance in almost all HCV genotypes at DAA failures: What are the chances for second-line regimens?

Prevalence of Single and Multiple Natural NS3, NS5A and NS5B Resistance-Associated Substitutions in Hepatitis C Virus Genotypes 1-4 in Italy

AbstractNatural resistance-associated substitutions (RASs) are reported with highly variable prevalence across different HCV genotypes (GTs). Frequency of natural RASs in a large Italian real-life cohort of patients infected with the 4 main HCV-GTs was investigated. NS3, NS5A and NS5B sequences were analysed in 1445 HCV-infected DAA-naïve patients. Sanger-sequencing was performed by home-made protocols on 464 GT1a, 585 GT1b, 92 GT2c, 199 GT3a, 16 GT4a and 99 GT4d samples. Overall, 20.7% (301/1455) of patients showed natural RASs, and the prevalence of multiclass-resistance was 7.3% (29/372 patients analysed). NS3-RASs were particularly common in GT1a and GT1b (45.2-10.8%, respectively), mai…

Improvement of ALT decay kinetics by all-oral HCV treatment: Role of NS5A inhibitors and differences with IFN-based regimens

Background Intracellular HCV-RNA reduction is a proposed mechanism of action of direct-acting antivirals (DAAs), alternative to hepatocytes elimination by pegylated-interferon plus ribavirin (PR). We modeled ALT and HCV-RNA kinetics in cirrhotic patients treated with currently-used all-DAA combinations to evaluate their mode of action and cytotoxicity compared with telaprevir (TVR)+PR. Study design Mathematical modeling of ALT and HCV-RNA kinetics was performed in 111 HCV-1 cirrhotic patients, 81 treated with all-DAA regimens and 30 with TVR+PR. Kinetic-models and Cox-analysis were used to assess determinants of ALT-decay and normalization. Results HCV-RNA kinetics was biphasic, reflecting …

Multiclass HCV resistance to direct-acting antiviral failure in real-life patients advocates for tailored second-line therapies

Background & Aims: Despite the excellent efficacy of direct-acting antivirals (DAA) reported in clinical trials, virological failures can occur, often associated with the development of resistance-associated substitutions (RASs). This study aimed to characterize the presence of clinically relevant RASs to all classes in real-life DAA failures. Methods: Of the 200 virological failures that were analyzed in 197 DAA-treated patients, 89 with pegylated-interferon+ribavirin (PegIFN+RBV) and 111 without (HCV-1a/1b/1g/2/3/4=58/83/1/6/24/25; 56.8% treatment experienced; 65.5% cirrhotic) were observed. Sanger sequencing of NS3/NS5A/NS5B was performed by home-made protocols, at failure (N= 200) and w…