Impact of adherence on response to therapy during treatment for acute and early chronic HCV infection

  • Jason Grebely, National Centre in HIV Epidemiology and Clinical Research, University of New South Wales, Australia
  • Dr Margaret Hellard, Burnet Institute, Australia
  • Dr Paul Haber, Drug Health Service, Royal Prince Alfred Hospital, Australia
  • Dr Gail Matthews, National Centre in HIV Epidemiology and Clinical Research, University of New South Wales, Australia
  • Dr Kathy Petoumenos, National Centre in HIV Epidemiology and Clinical Research, University of New South Wales, Australia
  • Dr Andrew Lloyd, School of Medical Sciences, University of New South Wales, Australia
  • Dr John Kaldor, National Centre in HIV Epidemiology and Clinical Research, University of New South Wales, Australia
  • Dr Gregory Dore, National Centre in HIV Epidemiology and Clinical Research, University of New South Wales, Australia

    • Objectives: To evaluate factors associated with sustained virologic response (SVR), including the impact of adherence during treatment for newly acquired HCV infection.

    Methods: ATAHC is a prospective study of the natural history and treatment of acute/early chronic HCV. Treated subjects received 24 weeks of pegylated interferon alfa-2a (with ribavirin if HIV co-infected). Subjects were eligible if they were within 6 months of their first anti-HCV antibody positive result and had either clinical HCV within the past 12 months (acute cases) or documented anti-HCV seroconversion within the preceding 24 months (early chronic cases). We evaluated factors associated with sustained virologic response (SVR) following treatment for HCV and the impact of adherence during the first 12 weeks on response.

    Results: Of 68 subjects (76% male, 54% genotype 1), 78% had a history of injection drug use, 28% were HIV co-infected and 63% had early chronic HCV infection (duration >24 weeks). The overall SVR was 60%. Among subjects with and without a history of injecting, SVRs were 49% (26/53) and 100% (15/15), respectively. SVR was 68% and 25% among subjects with >80% and <80% adherence. Using multivariate analysis, a poor social functioning score (AOR=0.10, 95% CI=0.02-0.49, p=0.005), injection drug use during treatment (AOR=0.16, 95% CI=0.02-1.00, p=0.005) and having ever been in drug/alcohol treatment (AOR=0.16, 95% CI=0.03-0.81, p=0.027) were associated with reduced SVR. Subjects with adherence <80% during the first 12 weeks (n=7) demonstrated lower rates of rapid virologic response (RVR), EVR and SVR as compared to subjects >80% adherent (n=61). Among adherent subjects, RVR, EVR and SVR were higher among subjects with low baseline viral load.

    Conclusions: Favorable HCV treatment outcomes were observed following treatment for newly acquired HCV infection and are improved among adherent subjects. Developing strategies to enhance HCV adherence early during HCV treatment in injection drug users is important.