Combination ruzasvir (RZR) 60 mg and uprifosbuvir (UPR) 450 mg is well-tolerated among patients with hepatitis C virus (HCV) infection, although its efficacy varies by HCV genotype (GT), according to results published in the Journal of Viral Hepatology.
RZR is an HCV nonstructural protein 5A complex inhibitor with pangenotypic activity in vitro against resistance-associated substitutions. UPR is an HCV nonstructural protein 5B polymerase nucleotide inhibitor with pangenotypic activity in vitro and a high barrier to resistance.
The study included participants with HCV GT 1-6 infection (N=160). Participants received RZR 60 mg plus UPR 450 mg orally once daily for 12 weeks. The primary endpoint was sustained virologic response at 12 weeks after the end of treatment. Of 160 participants, 54 had HCV GT1a infection, 15 had GT1b, 29 had GT2, 39 had GT3, 20 had GT4, 0 had GT5, and 3 had GT6.
After follow-up, the rates of sustained virologic response at 12 weeks were 96% (n=52) for HCV GT1a infection, 100% (n=15) for GT1b, 97% (n=28) for GT2, 77% (n=30) for GT3, 90% (n=18) for GT4, and 67% (n=2) for GT6.
The most commonly reported drug-related adverse events were fatigue (6.3%; n=10) and diarrhea (5.6%; n=9). A total of 11 serious adverse events were reported by 5 participants, but none was considered drug related.
“Uprifosbuvir 450 mg plus RZR at the higher dose of 180 mg once daily for 12 weeks is undergoing investigation in participants with HCV GT1, GT2, GT3, GT4, or GT6 infection to evaluate whether a higher dose of RZR can achieve higher efficacy rates, particularly in GT1a-, GT3- and GT6-infected people,” the researchers wrote.
Please see the original reference for a full list of authors’ disclosures.
Lawitz E, Poordad F, Anderson LJ, et al. Efficacy and safety of ruzasvir 60 mg and uprifosbuvir 450 mg for 12 weeks in adults with chronic hepatitis C virus genotypes 1, 2, 3, 4, or 6 infection [published online February 9, 2019]. J Viral Hepat. doi: 10.1111/jvh.13079