VIENNA — Twenty-four weeks of treatment with Harvoni yielded a 12-week sustained virologic response rate higher than 70% in a cohort of patients who had failed previous therapies, according to data presented at the 2015 International Liver Congress.
Eric J. Lawitz, MD, of the Texas Liver Institute at the University of Texas Health Science Center in San Antonio, and colleagues studied the fixed-dose combination of Harvoni (ledipasvir/sofosbuvir, Gilead Sciences) for 24 weeks in 41 genotype 1 HCV-infected patients who had failed previous therapies in phase 2 studies.
Response rates were 95% at week 4 of study, 98% at end of treatment, 73% for SVR4 and 71% for SVR12.
“We studied SVR12 rates in terms of three important criteria,” Lawitz said. “We looked at the impact of cirrhosis, the effect of previous treatment duration and the presence or absence of [resistance-associated variants] at baseline.”
SVR12 rates were 68% in patients without cirrhosis and 74% in those with cirrhosis.
“There was little numerical difference in rates of SVR12 irrespective of the presence or absence of cirrhosis,” Lawitz said.
For prior duration, 8 weeks of previous therapy yielded an 80% SVR12 rate, compared with 46% for patients treated for 12 weeks.
Patients with no baseline NS5A RAVs experienced 100% SVR12, while those with baseline RAVs reached SVR12 at 60%.
“Increasing numbers of NS5A RAVs led to a numeric decrease in SVR12,” Lawitz said.
Patients with Q30R or M28T RAVs had 100% SVR12, while those with L31M had 80% SVR12 and those with Y93H/N RAVs had just 33% SVR12.
The emergence of S282T was observed in three of 12 virologic failures.
The overall adverse event rate was 49%, with two serious events, both of which were unrelated to study drugs, according to Lawitz. There were no deaths and two isolated grade 3 lab abnormalities with no significant consequences. Headache was the most frequent event, which occurred in 15% of the population.
“The majority of events were mild to moderate in severity,” Lawitz said. – by Rob Volansky