Despite the high efficacy of direct acting antivirals (DAAs) not all patients successfully clear hepatitis C virus infection, in fact, approximately 1–3% fail to reach a sustained virological response 12 weeks after end of treatment. DAA failures are characterized by advanced liver disease, specific genotypes/subtypes and resistance associated substitutions to the DAA class they have been treated with. Current European Association for the Study of the Liver guidelines recommend three therapeutic options for such patients. The first is a 12 week course of sofosbuvir (SOF), velpatasvir (VEL) and voxilaprevir (VOX), which has shown to be effective in 90–99% of patients and was granted A1 level recommendation. The second option, reserved for patients who have predictors of failure consists in 12 weeks regimen with glecaprevir (GLE) and pibrentasvir (PIB), effective in 90–97%. Finally, although not supported by published data, for especially difficult to treat patients there should theoretically be a benefit in prolonged combinations of SOF+GLE/PIB or SOF/VEL/VOX±ribavirin. This review presents the latest evidence from both clinical trials and real-life on such therapeutic strategies.
Antiviral Agents ; Financing, Organized ; Hepacivirus ; Hepatitis C ; Hepatitis ; Humans ; Liver ; Liver Diseases ; Sofosbuvir ; Treatment Failure

Objective To investigate some pathogenic characters of Salmonella enterica strains isolated from poultry. Methods Twenty-three genetically distinct Salmonella enterica strains, of different serovars and pulsotype, were examined for virulence traits. Resistance to gastric acid environment was estimated by measuring the percentage of survived bacterial cells after exposure for 2 h to a synthetic gastric juice. Strains were analyzed with PCR for the presence of the following virulence genes: mgtC and rhuM located on SPI-3, sopB and pipB located on SPI-5, Salmonella virulence plasmid (spv) R (spvR), spvB and spvC located on Salmonella plasmid virulence and sodCI, sopE, and gipA located on prophage. Finally, resistance to 21 antibiotics was tested with Kirby–Bauer method. Results A percentage of 82.60% of strains were resistant to gastric environment after induction and 60.87% of the strains exhibited constitutive resistance too. Nineteen different virulence profiles were detected. The phage related genes sodCI and sopE and the plasmid mediated operon spvR, spvB and spvC (spvRBC) were detected in 82.60%, 47.82% and 52.17% of strains, respectively. Typhimurium and Enteritidis strains showed the highest number of virulence genes. Twenty-one different antibiotic resistance profiles were obtained and two isolates (Typhimurium and Enteritidis) resulted sensible to all the tested molecules. The ampicillin, streptomycin, sulfonamide and tetracycline resistance profile was detected in seven isolates (30.43%). Conclusion Our results show that paratyphoid Salmonella strains with several characters of pathogenicity, that may be cause of severe pathology in animals and humans, are circulating among poultry.