Ribavirin induces hepatitis C virus genome mutations in chronic hepatitis patients who failed to respond to prior daclatasvir plus asunaprevir therapy

Abstract

Ribavirin (RBV) induces nucleotide (nt) substitutions in hepatitis C virus (HCV) genome nonstructural (NS) regions. Although emergence of drug resistance‐associated variants is associated with direct‐acting antiviral treatment failure, the effect of RBV on genome substitutions in such patients is unknown. Genotype 1b HCV subgenomic replicon cells were treated with RBV for 120 hours. Six patients with chronic genotype 1b with HCV‐infected patients who failed to respond to prior daclatasvir plus asunaprevir (DCV/ASV) therapy were treated with 12 weeks of sofosbuvir and ledipasvir plus RBV after 4 weeks of RBV monotherapy. RBV‐induced genome mutations in the HCV NS region (nt3493‐9301) in replicon cells and in patients during 4 weeks of RBV monotherapy were analyzed by deep sequencing. RBV‐associated G‐to‐A and C‐to‐U transitions increased in a dose‐dependent manner in HCV replicon cells after the RBV treatment. In patients with prior DCV/ASV treatment failures, the median serum HCV RNA level was 6.25 ± 0.31 log IU/mL at the start of RBV therapy and decreased significantly to 5.95 ± 0.4 log IU/mL (P = .03) after 4 weeks of RBV monotherapy. Although predominant HCV genome substitutions rates were similar between nontreatment and RBV‐treatment periods (0.042 and 0.031 per base pair, respectively; P = .248), the frequencies of G‐to‐A and C‐to‐U transitions significantly increased after RBV monotherapy. These transitions were enriched, particularly within the HCV NS3 region in all patients. RBV treatment induces G‐to‐A and C‐to‐U transitions in the HCV genome even in chronic patients with hepatitis C with prior DCV/ASV treatment failures.

Mutational spectrum of hepatitis C virus in patients with chronic hepatitis C determined by single molecule real-time sequencing

“…The higher frequency of transition mutations compared to transversion mutations may be explained by viral polymerase fidelity. The same mutation patterns among in vitro biochemical analysis in HCV replicon cells and HCV-infected patients 20 , 22 , 24 suggests that the RdRp fidelity of HCV NS5B is a major factor in establishing the mutational spectrums of HCV RNA. Moreover, the higher frequency of the A>G and U>C than G>A and C>U transition substitutions are also thought to arise from the fidelity of HCV NS5B.…”

“…C>U transition was the most frequent substitution among transitions). Previous reports have demonstrated that ribavirin induces C>U and G>A substitutions in HCV genome 24 , 26 , 27 . Therefore, the alterative mutation pattern during interferon-based therapy may be caused by the administration of ribavirin.…”

“…Recently, Geller et al clarified that the main factors responsible for the heterogeneity of HCV were base composition, the presence of high- and low-mutation clusters, and transition/transversion biases 20 . In fact, the HCV mutational repertoire was found to be dominated by transitions in comparison to transversions 20 , 22 – 24 . For example, using HCV replicon cell lines with long-term culture for 9 years, Kato et al reported that transition mutations were more frequent than transversion mutations, resulting in an increase in the GC content of replicon RNA in a time-dependent manner 23 .…”

Safety and efficacy of sofosbuvir-velpatasvir: A meta-analysis

“…Based on differences in nucleotide sequences, HCV is divided into 8 genotypes with different geographical distribution, influencing disease progression and treatment response. [2] The most common genotype (GT) is GT1, which accounts for more than half of all HCV-infected patients worldwide, another common genotypes are GT3 and GT4. [3] Failure to provide antiviral treatment timely and effectively will lead to HCV progression, even leading to the most serious complications, including cirrhosis, liver function damage, hepatocellular carcinoma, etc.…”

“…Based on differences in nucleotide sequences, HCV is divided into 8 genotypes with different geographical distribution, influencing disease progression and treatment response. [ 2 ] The most common genotype (GT) is GT1, which accounts for more than half of all HCV-infected patients worldwide, another common genotypes are GT3 and GT4. [ 3 ]…”