Page 44 - The Flying Publisher Guide to Hepatitis C Treatment

44 | Hepatitis C Treatment

– the correctable factors of treatment failure during the
previous course of therapy.
Consistent with the change in HCV RNA during the previous
course of therapy, four different patterns of treatment failure
– with crucial implications for the regimen, duration and
likelihood of response to retreatment – can be distinguished:
1. Patients with less than 2 log 10 UI/ml decline in HCV RNA
from baseline to treatment week 12 are defined as non-
responders. Within this group, null responders show a
minimal reduction in HCV RNA level (usually less than 1
log 10 UI/ml), being considered the most refractory group to
treatment with pegylated interferon alfa (PegIFN) and
ribavirin (RBV). SVR rates during retreatment rarely
surpass 15% in this population. Therefore, unless other
compelling reasons impose therapy in these patients (such
as control of extrahepatic manifestations or advanced liver
disease), the best option may be to closely monitor them
while waiting for triple therapy (PegIFN/RBV + a direct-
acting antiviral).
2. Patients with ≥2 log 10 UI/ml decline in HCV RNA from
baseline to treatment week 12, who remain HCV RNA
detectable at week 24 are partial virological responders.
3. Breakthrough is defined as detectable HCV RNA during
therapy, after an initial virologic response (HCV RNA
undetectable or ≥2 log 10 UI/ml decline at week 12).
4. In contrast to previous categories, relapsers are those who,
during therapy, achieved and maintained undetectable HCV
RNA (measured by a high sensitive assay), but HCV RNA
become again measurable during the first 6 months after the
end of therapy. Relapsers have the best chance of
achieving SVR during retreatment with PegIFN/RBV, with a
SVR rate of approximately 40%. Triple therapy with a
protease inhibitor further increase this rate.
Numerous host and virological factors strongly influence the
response to therapy. A complex constellation of fixed factors
related to virus, such as genotype 1 or high pre-therapeutic viral