title: Response-guided therapy for patients with hepatitis C virus genotype 6 infection: a pilot study.
abstract: The optimal duration of treatment with pegylated interferon (PEG-IFN) plus ribavirin (RBV) in patients with hepatitis C virus (HCV) genotype 6 is unknown. This study was aimed at determining treatment response on the basis of rapid virological response (RVR) of HCV genotype 6 in comparison with genotypes 1 and 3. Sixty-six treatment naïve patients were treated with PEG-IFN-α2a (180 μg/week) plus weight-based RBV (1000-1200 mg/day). Patients with genotype 1 n = 16) and genotype 3 (n = 16) were treated for a fixed duration of 48 and 24 weeks, respectively. Patients with genotype 6 (n = 34) who achieved RVR were treated for 24 weeks (response-guided therapy) and the remaining patients were treated for 48 weeks (standard therapy). The mean baseline HCV RNA levels were not statistically different between groups (6.4 ± 0.8, 6.0 ± 1.0 and 6.5 ± 0.8 Log(10) IU/mL for genotypes 1, 3 and 6, respectively). Patients with genotypes 1, 3 and 6 achieved RVR in 43.8%, 87.5% and 73.5% of cases, respectively. One patient with genotype 1 and 3 with genotype 6 were considered nonresponders and discontinued therapy. Sustained virological response (SVR) was achieved in 62.5%, 81.3% and 76.5% of patients with genotypes 1, 3 and 6, respectively. The SVR rate in patients with genotype 6 who underwent response-guided therapy was 88%. This pilot study suggested that the SVR rate of HCV genotype 6 was at an intermediate level between those of genotypes 3 and 1. Treatment with PEG-IFN plus RBV for 24 weeks may be sufficient for patients with genotype 6 who achieve RVR. Prospective randomized trials are required to evaluate this response-guided strategy in a larger number of patients with genotype 6.
authors.affiliation: Department of Biochemistry, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand.
authors.forename: P
authors.initials: P
authors.lastname: Tangkijvanich
authors.forename: P
authors.initials: P
authors.lastname: Komolmit
authors.forename: V
authors.initials: V
authors.lastname: Mahachai
authors.forename: K
authors.initials: K
authors.lastname: Poovorawan
authors.forename: S
authors.initials: S
authors.lastname: Akkarathamrongsin
authors.forename: Y
authors.initials: Y
authors.lastname: Poovorawan
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000998:Antiviral Agents / Q000008:administration & dosage*; D016903:Drug Monitoring / Q000379:methods*; D005260:Female; D005838:Genotype; D016174:Hepacivirus / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*; D019698:Hepatitis C, Chronic / Q000188:drug therapy* / Q000821:virology*; D006801:Humans; D016898:Interferon-alpha / Q000008:administration & dosage*; D008297:Male; D008875:Middle Aged; D011092:Polyethylene Glycols / Q000008:administration & dosage*; D012367:RNA, Viral / Q000097:blood; D011994:Recombinant Proteins / Q000008:administration & dosage; D012254:Ribavirin / Q000008:administration & dosage*; D013997:Time Factors; D016896:Treatment Outcome; D019562:Viral Load; D055815:Young Adult
chemical_list: D000998:Antiviral Agents; D016898:Interferon-alpha; D012367:RNA, Viral; D011994:Recombinant Proteins; D011092:Polyethylene Glycols; D012254:Ribavirin; C100416:peginterferon alfa-2a