SAN FRANCISCO – The investigational combination of ombitasvir, paritaprevir, and ritonavir when given with sofosbuvir (OBV/PTV/r + SOF) for 12 weeks appears to be a highly effective treatment option for patients with hepatitis C virus genotype 3 infection, according to findings from the open-label, phase II QUARTZ-II/III study.
The treatment, when given with ribavirin for 8 weeks, also appears highly effective for genotype 2 infection, Dr. Stephen Shafran reported in a late-breaking poster at the annual meeting of the American Association for the Study of Liver Diseases.
In the multicenter study, 20 patients with HCV genotype 3 (GT3) infection, including 10 with prior treatment experience, were randomized to receive OBV/PTC/r + SOF either with or without ribavirin (11 and 9 patients, respectively), and with the exception of 1 patient who discontinued the study because of nonserious events, all had HCV RNA suppressed less than 25 IU/mL by treatment week 2 and through the end of treatment.
Sustained virologic response (SVR) at 12 weeks was achieved in 9 of 9 patients who had been treated with OBV/PTV/r + SOF for 12 weeks, and in 10 of 11 who were treated with OBV/PTV/r + SOF + ribavirin for 12 weeks, said Dr. Shafran, a professor at the University of Alberta, Canada.
Additionally, 10 patients with HCV GT2 infection in the study, including 2 with treatment experience, were treated with OBV/PTV/r + SOF + ribavirin for 8 weeks, and all were HCV RNA–suppressed at the end of treatment. SVR4 was 90%, Dr. Shafran said.
Treatment in both GT3 and GT2 patients was well tolerated, with only one patient experiencing a serious adverse event (pneumonia), which was not considered related to study drugs.
The findings are notable, as few interferon-free treatments are approved for HCV GT3 and GT2 infection, and those that are available are associated with SVR rates that are lower at 12 weeks among those with cirrhosis or prior treatment failure, he said.
The current findings, however, suggest that OBV/PTV/r + SOF is a promising interferon- and ribavirin-free treatment option for patients with GT3 infection, and a highly effective combination when administered with ribavirin in patients with GT2 infection, including among patients with cirrhosis or prior treatment failure, he concluded.
Dr. Shafran is an advisory committee or review panel member for Bristol-Myers Squibb, Gilead Sciences, and Merck, and has received grant or research support from AbbVie, Bristol-Myers Squibb, Gilead Sciences, Janssen, and Merck.