Interferon Treatment Raises Hepatitis C Cure Rate
Meta-analysis finds that extending pegylated interferon plus
ribavirin to 72 weeks may improve sustained response rates
for late-responder genotype 1 hepatitis C patients.
standard-of-care treatment for chronic
hepatitis C virus (HCV) infection consists of pegylated
interferon (Pegasys or PegIntron) plus ribavirin for either
24 weeks (for people with HCV genotypes 2 or 3) or 48 weeks (for
hard-to-treat genotypes 1 or 4).
direct-acting antiviral agents will usher in a new paradigm in
hepatitis C treatment. The first 2 drugs out of the pipeline --
-- were recommended for FDA approval in late April. While these
agents will likely eventually be used in all-oral regimens, initially
they will be combined with pegylated interferon/ribavirin.
therapy can be difficult to tolerate, however, with side effects
including depression, flu-like symptoms, and anemia. Researchers
have therefore explored response-guided therapy, using HCV viral
load reduction at 4 or 12 weeks to predict whether an individual
could achieve a cure with shorter therapy or, alternatively, is
unlikely to achieve sustained response at all, so should avoid
further futile therapy. Prolonged therapy for hard-to-treat or
slow-responding patients has not been so well studied.
described in the April
2011 Journal of Viral Hepatitis, M. Parikh from Baylor
College of Medicine and colleagues performed a systematic review
and meta-analysis of 5 studies, comparing outcomes with 48 weeks
vs 72 weeks of interferon-based therapy for treatment-naive genotype
1 chronic hepatitis C patients with late virological response,
defined as failure to achieve a significant reduction in HCV viral
load by week 12 of treatment.
response rates were statistically similar with extended 72-week
and standard 48-week treatment, at 48% vs 56%, respectively
(pooled odds ratio [OR] 0.85).
sustained virological response (SVR) rates after completion
of therapy were higher with 72 weeks compared with 48 weeks
of treatment, at 32% vs 25%, respectively (pooled OR 1.67).
The improvement in sustained response was attributable to
a lower post-treatment relapse rate with extended duration
therapy (35% vs 55%, respectively; OR 0.39).
the treatment duration from 48 to 72 weeks in genotype 1 infected
patients with late virological response improves SVR," the
study authors concluded. "Thus, therapy extension in genotype
1 late viral responders may be a consideration to improve treatment
they added, the proportion of patients with late virological response
who might benefit from 72-week therapy "appears to be small."
proportion will likely become even smaller with the advent of the
direct-acting agents, which have been shown to shorten the required
duration of therapy for many patients and to reduce the likelihood
affiliations: Department of Internal Medicine, Baylor College of
Medicine, Houston, TX; Department of Gastroenterology and Hepatology,
University of Texas Medical Branch, Galveston, TX; Department of
Gastroenterology and Hepatology, Baylor College of Medicine, Houston,
Parikh, A Singh, and G Sood. Extended treatment duration for treatment
naive chronic hepatitis C genotype 1 late viral responders: a meta-analysis
comparing 48 weeks vs 72 weeks of pegylated interferon and ribavirin.
Journal of Viral Hepatitis 18(4):e99-103 (abstract).