title: Review article: the efficacy and safety of sofosbuvir, a novel, oral nucleotide NS5B polymerase inhibitor, in the treatment of chronic hepatitis C virus infection.
abstract: BACKGROUND
  The treatment of chronic hepatitis C is changing rapidly.
  
  
  OBJECTIVE
  To review clinical studies of the efficacy and safety of sofosbuvir-containing regimens in the treatment of chronic hepatitis C.
  
  
  METHODS
  Using PubMed and search terms 'sofosbuvir,' 'emerging HCV treatment,' and 'HCV polymerase inhibitor,' literature on the clinical development of sofosbuvir, as well as abstracts presented at the November 2013 annual meeting of the American Association for the Study of Liver Diseases (AASLD), was reviewed. The last search was undertaken on 15 November 2013 [corrected].
  
  
  RESULTS
  In a dose of 400 mg once daily, the drug has been safe and generally well tolerated with most adverse reactions attributable to the concurrent use of ribavirin or peginterferon plus ribavirin. A high barrier to resistance has been demonstrated. In genotype 1 (G1) patients, the addition of sofosbuvir to peginterferon plus ribavirin yielded sustained virological response rates at week 12 after discontinuation of treatment (SVR12) of about 90% with slightly lower levels in G1b and in patients with cirrhosis, but with no major impact of IL28B genotype, high viral load, body mass index (BMI), alanine aminotransferase (ALT) or race/ethnicity. In genotype 2 (G2), sofosbuvir and ribavirin for 12 weeks also resulted in SVR12 of 90% or better with little effect from cirrhosis. In contrast, genotype 3 (G3) was less responsive to 12 weeks of sofosbuvir plus ribavirin, especially in the presence of cirrhosis.
  
  
  CONCLUSIONS
  The efficacy and safety of sofosbuvir-containing regimens with ribavirin alone or with peginterferon plus ribavirin signal a new era in treatment.
authors.affiliation: Department of Gastroenterology and Hepatology, Department of Medicine, University of Connecticut Health Science Center, Farmington, CT, USA.
authors.forename: R S
authors.initials: RS
authors.lastname: Koff
mesh_terms: D000998:Antiviral Agents / Q000627:therapeutic use*; D004359:Drug Therapy, Combination; D004791:Enzyme Inhibitors / Q000627:therapeutic use; D005838:Genotype; D016174:Hepacivirus / Q000235:genetics; D019698:Hepatitis C, Chronic / Q000188:drug therapy*; D006801:Humans; D007372:Interferons / Q000627:therapeutic use; D012254:Ribavirin / Q000627:therapeutic use; D000069474:Sofosbuvir; D016896:Treatment Outcome; D014542:Uridine Monophosphate / Q000031:analogs & derivatives* / Q000627:therapeutic use; D017361:Viral Nonstructural Proteins / Q000037:antagonists & inhibitors*; D012324:RNA-Dependent RNA Polymerase
chemical_list: D000998:Antiviral Agents; D004791:Enzyme Inhibitors; D007372:Interferons; D012254:Ribavirin; D000069474:Sofosbuvir; D014542:Uridine Monophosphate; D017361:Viral Nonstructural Proteins; C087036:NS-5 protein, hepatitis C virus; D012324:RNA-Dependent RNA Polymerase