Intrahepatic Viral Kinetics during Direct-Acting Antivirals for Hepatitis C in HIV Co-infection:The ACTG A5335S Substudy.

Direct-acting antivirals (DAA) targeting hepatitis C virus (HCV) have revolutionized outcomes in HIV co-infection. We examined early events in liver and plasma through A5335S, a substudy of trial A5329 (paritaprevir/ritonavir, ombitasvir, dasabuvir, with ribavirin) that enrolled chronic genotype 1a HCV-infected persons co-infected with suppressed HIV: 5/6 treatment-naïve enrollees completed A5335S. Mean baseline plasma HCV RNA=6.7 log10 IU/mL and changed by -4.1 log10 IU/mL by Day 7. In liver, laser capture microdissection was used to quantify HCV. At liver biopsy 1, mean (95% CI) %HCV-infected cells=25.2% (7.4%, 42.9%), correlating with plasma HCV RNA (Spearman rank correlation r=0.9); biopsy 2 (Day 7 in 4/5 participants) mean (95% CI) %HCV-infected cells=1.0% (0.2%, 1.7%)(p<0.05 for change), and DAAs were detectable in liver. Plasma CXCL10 concentrations changed by mean=-160 pg/mL/day at 24 hours, but no further after Day 4. We conclude that HCV infection is rapidly cleared from liver with DAA leaving <2% HCV-infected hepatocytes at Day 7. We extrapolate that HCV eradication could occur in these participants by 63 days, although immune activation might persist. Single-cell longitudinal estimates of HCV clearance from liver have never been reported previously and could be applied to estimating the minimum treatment duration required for HCV infection.