Changes of inflammatory cytokines/chemokines during ravidasvir plus ritonavir-boosted danoprevir and ribavirin therapy for patients with genotype 1b hepatitis C infection

Antiviral treatment significantly reduces the levels of CXCL9, CXCL10 and CXCL11 in chronic hepatitis C

In this study, we aimed to elucidate the changes in the immune response during antiviral treatment of patients with chronic hepatitis C, with an emphasis on the chemokine dynamics and their association with liver fibrosis. Serum concentrations of 12 chemokines. (CCL2, CCL3, CCL4, CCL11, CCL17, CCL20, CXCL1, CXCL5, CXCL8, CXCL9, CXCL10 and CXCL11) were measured in 32 patients with chronic hepatitis C before direct-acting antiviral treatment and after sustained virological response using bead-based flow cytometry. Chemokine levels were also measured in 14 sex- and age-matched healthy individuals. Concentrations of CXCL9, CXCL10, CXCL11 and CCL20 were significantly higher in chronic hepatitis C patients before direct-acting antiviral treatment compared to healthy individuals. We also observed a significant reduction in CXCL9, CXCL10 and CXCL11 levels after sustained virological response. Furthermore, we demonstrated a strong positive correlation between CXCL9, CXCL10 and CXCL11 levels before antiviral treatment. When considering liver fibrosis, we found significantly higher levels of CXCL10 and lower levels of CCL17 and CXCL5 in pre-treatment patients with severe fibrosis. None of the analysed chemokines were able to predict METAVIR fibrosis score reduction after sustained virological response. The results of this study emphasize the importance of proinflammatory pathways in liver fibrosis immunopathology during chronic hepatitis C. Finally, our results also characterized CXCL10 as the chemokine which most accurately distinguished pre-treatment CHC patients and healthy individuals.

Pharmacokinetics, safety and tolerability of ravidasvir, with and without danoprevir/ritonavir, in healthy subjects

Ravidasvir (RDV) is a novel oral hepatitis C virus NS5A inhibitor. This study aimed to evaluate the pharmacokinetics and safety of RDV and the drug-drug interaction between RDV and ritonavir-boosted danoprevir (DNVr) in healthy adults. In 1^st study, healthy volunteers were administered oral single doses of 100, 200 and 300 mg RDV and 200 mg once daily for 7 days. The 2^nd study was randomized, double-blind and placebo-controlled sequential design (day 1 for 200 mg RDV alone, day 7 for 100 mg/100 mg DNVr, day 13 for 200 mg RDV plus 100mg/100mg DNVr, followed by RDV 200 mg once daily with DNVr 100mg/100mg twice daily for 10 days). The results showed that RDV exposure increased in a dose-proportional manner following a single dose with no evidence of accumulation with multiple doses. Co-administration with DNVr regimen (100 mg/100 mg, twice daily) resulted in a 2.92- and 1.99-fold increase in minimum plasma concentration at steady state (C_min,ss) and area under the concentration-time curve at steady state (AUC_τ) of RDV. With co-administration of RDV, maximum plasma concentration (C_max) and area under the concentration curve from zero to 12 h (AUC_0-12) of DNV increased 1.71-fold and 2.33-fold, respectively. We did not observe any significant changes in ritonavir exposure. Both single and multiple doses of RDV with or without DNVr were well tolerated. The favorable pharmacokinetic and safety results support ravidasvir's continued clinical development and treatment.