Additional Relevant Details The primary endpoint of the study was sustained virologic response at post-treatment week 24 (SVR24). In the study, 91% of patients from China achieved SVR24, which rose to 98% of patients without NS5A resistance-associated variants (RAVs) at baseline. SVR24 results were similarly high across all subgroups with genotype 1b HCV, including those with cirrhosis (90%), and patients from Korea (94%) and Taiwan (87%).
SVR24 rates were also higher in all patients without baseline NS5A RAVs (n=137/139 [99%]), regardless of the presence (98%) or absence (99%) of cirrhosis, and lower in patients with baseline NS5A RAVs (n=8/19 [42%]). Baseline NS5A RAVs were present in 12% of patients. HCV NS5A RAVs exist naturally (albeit in lower prevalence vs wildtype) and can emerge after virologic response failure. Screening for the presence of specific NS5A mutations can help physicians determine the best patients for treatment by identifying those most likely to achieve cure with an NS5A-containing regimen.In the trial presented today, across all patient cohorts, all serious adverse events (SAEs) (n=5/159 [3%]), grade 4 laboratory abnormalities (n=3/159 [1.9%]) and deaths (n=1/159 [1%]) that occurred on treatment were unrelated to the study drugs. Two patients discontinued due to adverse events (AEs). The most common AEs (> 5% of patients) were decrease in platelets (9%), upper respiratory tract infection (8%), ALT increase (7%), ANC decrease (7%), monocyte decrease (6%), white blood cell decrease (6%), thrombocytopenia (6%), and pruritus (6%).