Rafael Esteban of Vall d’Hebron Hospital in Barcelona and colleagues
looked people with HCV genotypes 2 or 3 who relapsed after receiving sofosbuvir/ribavirin
for 12 weeks in prior pivotal trials. This study aimed to determine if
retreating these patients with the same regimen for a longer duration or adding
pegylated interferon would improve cure rates.
As previously reported, 97% of
treatment-naive participants with genotype 2 in the FISSION trial achieved
SVR12, but this fell to 56% among people with genotype 3. In the POSITRON trial,
which looked at people ineligible or unwilling to take interferon, 93% of
people with genotype 2 and 61% of people with genotype 3 achieved SVR12. Among
treatment-experienced people in the FUSION trial, SVR12 rates were 86% and 30%,
This open-label study offered
participants the option of using sofosbuvir/ribavirin alone for 24 weeks or
sofosbuvir/ribavirin plus pegylated interferon for 12 weeks, based on
interferon eligibility and patient and investigator preference.
A total of 107 participants enrolled
in the study. About 80% were men, most were white and the mean age was 53
years. Almost all (93%) had HCV genotype 3, given that most genotype 2 patients
had previously been cured. About 35% had cirrhosis and a similar proportion had
the IL28B CC variant.
SVR12 data were available for 26
patients who opted for extended duration sofosbuvir/ribavirin and 40 who chose
to add interferon (the rest are still undergoing treatment or follow-up).
All participants in both treatment
groups had undetectable HCV viral load at week 4 and at the end of treatment.
However, there were several post-treatment relapses, resulting in SVR12 rates
of 63% in the 24-week sofosbuvir/ribavirin arm and 92% in the 12-week triple
Triple therapy worked well for
patients with or without cirrhosis (SVR12 rates of 88% and 93%, respectively).
However, extended sofosbuvir/ribavirin alone cured fewer than half (47%) of people with cirrhosis, compared with 74% of people who did not have cirrhosis.
Again, treatment was generally well
tolerated. Four people in the extended sofosbuvir/ribavirin arm and one in the
triple therapy arm experienced serious adverse events, though there were no
early discontinuations for this reason.
"The 12-week regimen containing
interferon had higher overall rates of SVR and was more effective in patients
with cirrhosis," the researchers concluded. "The 24-week
interferon-free regimen was safe and well tolerated and offers a retreatment
option for those ineligible to receive interferon."
As the other studies showed,
however, dual therapy with sofosbuvir and ledipasvir may be a more effective,
convenient and better tolerated retreatment option.