treatment for chronic hepatitis
C using pegylated interferon (Pegasys
or PegIntron) plus ribavirin produces sustained
response -- considered to be a cure -- about half the time,
with HCV genotypes 2
and 3 (treated for 24 week) showing better response rates
than hard-to-treat genotypes
1 or 4 (treated for 48 weeks).
Treatment is expensive and can cause difficult side effects,
however, so it is useful to have an early indicator to enable
patients to stop treatment that likely will not turn out to
F. Fred Poordad from Cedars-Sinai Medical Center in Los Angeles
and colleagues collected data from previous published clinical
trial reports in order to evaluate the predictive value of RVR
as an indicator of SVR and viral relapse.
supported a 24-week regimen for HCV genotype 1 patients
who achieved RVR.
positive predictive value -- or how often RVR accurately
predicted SVR -- was 77.8% for patients treated for 24 weeks
versus 85.7% for those treated for 48 weeks, not a significant
lack of RVR among genotype 1 patients "should not be
viewed as a criterion for extending treatment duration beyond
predictive values -- or how often lack of RVR predicted
failure to achieve SVR -- were 60.9% for genotype 1 patients
treated for 48 weeks and 52.7% for those treated for 72
weeks, not a significant improvement with longer therapy.
people with HCV genotypes 2 or 3, RVR also had a high positive
predictive value, however, varied according to treatment
duration, indicating that a 24-week regimen is warranted
for genotype 2 or 3 patients who did not achieve RVR.
on these findings, the study authors concluded, "The present
analysis confirms RVR as a strong predictor of SVR that can
be used to tailor treatment duration, but which also should
be appreciated in the context of treatment duration and regimen."
Investigator affiliation: Hepatology and Liver Transplantation,
Cedars-Sinai Medical Center, Los Angeles, CA.
Poordad. Review article: the role of rapid virological response
in determining treatment duration for chronic hepatitis C. Alimentary
Pharmacology and Therapeutics 31(12): 1251-1267 (Abstract).