A single dose of anti-miR-122, RG-101, in CHC patients results in NK cell normalization with no effect on HCV-specific CD8+ T cell function

Abstract

MicroRNA-122 (miR-122) is an important host factor for the hepatitis C virus. Treatment with RG-101, a GalNAc conjugated anti-miR-122 oligonucleotide, resulted in a significant viral load reduction in patients with chronic hepatitis C (CHC) infection. Here, we analyzed the effects of RG-101 therapy on antiviral immunity. 32 CHC patients HCV genotype 1, 3 and 4 received a single subcutaneous administration with RG-101 at 2 mg/kg (n=14), 4 mg/kg (n=14) or placebo (n=2 per dosing group). Plasma and PBMCs were collected at multiple time points and comprehensive immunological analyses were performed. Following RG-101 administration, HCV RNA declined in all patients (mean decline at week 2: 3.27 log10 IU/mL). At week 8 HCV RNA was undetectable in 15/28 patients. Plasma IP-10 levels declined significantly upon dosing with RG-101. Furthermore, the frequency of NK cells increased, and the proportion of markers for NK cells expressing activating receptors activity and differentiation normalized and NK cell IFN-γ production decreased after RG-101 dosing. By week 8 post RG-101 injection, fFunctional HCV-specific IFN-γ-T cell responses did not declined significantly change in patients who had undetectable HCV RNA by week 8 post RG-101 injection. No increase in the magnitude of HCV-specific T cell responses was observed at later time points, including 3 patients who were HCV RNA negative 76 weeks post dosing