To examine the treatment efficacy of a combination of pegylated interferon α (PegIFNa) plus ribavirin in patients chronically infected with hepatitis C virus genotype 5 (HCV-5) and to assess the on-treatment virological responses as predictors of sustained virological response (SVR).
HCV-5 is uncommonly reported, and little therapeutic data is available regarding previous retrospective studies yielding contradictory results.
In a prospective, open-label, single-center study, 27 treatment-naive HCV-5 patients, treated for 48 weeks with PegIFNa-2a/ribavirin, were evaluated. Rapid viral response (RVR), early viral response (EVR), 24-week viral response (24-wVR), end-of-treatment response (ETR), and SVR were assessed, defined as negative viral load at weeks 4, 12, 24, 48, and 72 after treatment initiation, respectively.
Attainment of SVR was observed in 17 of the 27 (63%) patients. RVR, EVR, and 24-wVR occurred in 16 (59.3%), 25 (92.6%), and 24 (88.9%) patients, respectively. All but 1 patient achieving 24-wVR went on to achieve ETR (rate: 85.2%), but 6 patients subsequently relapsed (relapse rate: 26.1%). The positive/negative predictive values on SVR were: 93.8%/81.8% for RVR, 68%/100% for EVR, and 66.7%/66.7% for 24-wVR.
Patients with HCV-5 showed an overall good response to a 48-week combined antiviral treatment (SVR: 63%). Albeit the ETR was high (85.2%), attainment of SVR remained affected by a substantial relapse rate, in our setting 26.1%. The predictive value of early viral dynamics on SVR merits adequate consideration in larger clinical trials targeting to optimize treatment for patients infected with HCV-5.