AMSTERDAM — Eight weeks of the fixed-dose combination of glecaprevir/pibrentasvir produced a 95% sustained virologic response rate in patients with genotype 3 hepatitis C virus, according to data presented at the International Liver Congress.
Foster, FRCP, PhD, of Queen Mary University of London, said that genotype 3 has been a “a bit of a stumbling block” in the direct-acting antiviral era. The current study included 233 patients assigned glecaprevir/pibrentasvir (G/P, AbbVie) for 12 weeks; 115 patients treated with Sovaldi (sofosbuvir, Gilead) and Daklinza (daclatasvir, Bristol-Myers Squibb) for 12 weeks, and then an additional arm that included 157 patients treated with G/P for 8 weeks.
“This was a simple study design,” Foster said. “The purpose of this study was to build on phase 2 data. We were asking a very simple question: Is 8 weeks as good as 12 weeks of g/p, or as good as 12 weeks of sofosbuvir/daclatasvir?”
Results indicated a 95% SVR12 rate for 12 weeks of the study regimen, 97% for sofosbuvir/daclatasvir and 97% for 8 weeks of glecaprevir/pibrentasvir. There was one treatment failure in the 12-week arm of glecaprevir/pibrentasvir, and one in the 8-week arm.
In terms of resistance, Foster said that the researchers “kicked the tires” on the data set to see if there were early signals. “If you have a single substitution in NS3 or NS5A, it makes no difference whatsoever to sustained response,” he said. “There was a weak, non-significant signal that if you have both NS3 and NS5A RAS, you may have a reduced response level, but we don’t know whether it’s a true signal or not.”
He added that patients with this dual resistance profile are rare.
Further analysis revealed no signals in terms of ALT, bilirubin, hemoglobin, platelets, and neutrophil counts. “The regimen was very well tolerated,” Foster said.
The researchers did not exclude patients who may or may not have been ongoing illicit drug users, according to Foster. “This was very much a real-world study,” he said. “Also, the mean age of patients was a bit lower than other studies, which, again, reflects our current practice.” – by Rob Volansky
Foster GR, et al. Abstract GS-007. Presented at: International Liver Congress; April 19-24, 2017; Amsterdam.
Disclosure: Foster reports being a consultant for AbbVie, Bristol-Myers Squibb, Gilead, GlaxoSmithKline, Janssen and Merck.