Direct-acting antiviral agents against hepatitis C virus and lipid metabolism

Metabolic aspects of hepatitis C virus

Many metabolic factors are associated with chronic hepatitis C virus (HCV) infection and can influence the course of the illness and impact the progression of liver and non-liver-related diseases through complex interactions. Several of these factors impact the course of chronic HCV (CHC) and result in the conceptual translation of CHC from a localized to systemic disease. Besides the traditional liver manifestations associated with CHC infection, such as cirrhosis and hepatocellular carcinoma, various extrahepatic disorders are associated with HCV infection, including atherosclerosis, glucose and lipid metabolic disturbances, alterations in the iron metabolic pathways, and lymphoproliferative diseases. The coexistence of metabolic disorders and CHC is known to influence the chronicity and virulence of HCV and accelerates the progression to liver fibrosis and hepatocellular carcinoma. Insulin resistance is one of the key factors that have a tremendous metabolic impact on CHC. Therefore, there is a great need to properly evaluate patients with CHC infection and correct the modifiable metabolic risk factors. Furthermore, patients with HCV who achieved a sustained virological response showed an overall improvement in glucose metabolism, but the exact evidence still requires further studies with long-term follow-up. This review delineates the most recent evidence on the main metabolic factors associated with CHC and the possible influence of chronic HCV infection on metabolic features.

Impact of HCV cure with drug-acting antivirals in the use of concomitant medication and lipid profile: follow-up data 2 years after the sustained virological response

BACKGROUND AND AIM

Patients with chronic hepatitis C (CHC) frequently associated comorbidities and concomitant medication. Sustained virological response (SVR12) has been related to an increase in cholesterol serum levels and in peripheral vascular resistance. Our aim was to evaluate the impact of SVR12 on the use of concomitant medication and serum lipid profile.

METHODS

Prospective study including patients treated with direct-acting antivirals who had achieved the SVR12. Clinical data and concomitant drugs were analysed at baseline and at least 1 year after SVR12. Differences from baseline to follow-up in the concomitant medication were evaluated by Stuart-Maxwell test and lipid profile by Wilcoxon signed-rank test. Patients were categorized according to the increase/decrease in the number of drugs included in each class (Anatomical Therapeutic Chemical classification system).

RESULTS

Two hundred twenty-six patients with SVR12 were included, 73.5% were receiving concomitant drugs (49.6% with antihypertensive effect, 30.5% antacids, 16.4% anti-diabetic drugs, and 7.1% lipid-lowering agents). One year after SVR12, total cholesterol serum levels increased from 161 to 179 mg/dl (P < 0.001) and, after a median time of 25.7 months, the use of lipid-lowering drugs increased from 7.8 to 11.5% (P = 0.009). In addition, we observed a trend to use more antihypertensive drugs in older patients (P = 0.06), especially in those with cirrhosis. Anxiolytics decreased after SVR12 from 13.7 to 10.6% (P = 0.035).

CONCLUSION

CHC cure is associated with a significant increase in cholesterol serum levels and the use of lipid-lowering agents, as well as the use of drugs with antihypertensive effect in older patients.

Real-world effectiveness and safety of ledipasvir/sofosbuvir for genotype 6 chronic hepatitis C patients in Taiwan

BACKGROUND AND AIM

Infection with hepatitis C virus (HCV) genotype (GT) 6 is uncommon in Taiwan, and reports of ledipasvir/sofosbuvir (LDV/SOF) treatment for GT6 are few. This study evaluates the effectiveness and safety of LDV/SOF in treating chronic hepatitis C (CHC) patients with GT6 infection.

METHODS

CHC patients that were infected with GT6 and treated for 12 weeks with LDV/SOF at two hospitals were enrolled. All patients were followed for an additional 12 weeks after the completion of LDV/SOF treatment. Demographics, HCV viral load, lipid and sugar profiles, and adverse events were recorded and reviewed.

RESULTS

A total of 127 patients were enrolled. Cirrhosis was found in 68.2% of them. Sustained virological response (SVR), determined by per-protocol analysis, was 97.6%. The SVR rates for cirrhosis versus non-cirrhosis (96.5% vs 100%, P = 0.229) and low versus high viral load (cutoff value: 10⁶  IU/mL; 100% vs 95.6%, P = 0.108) were similar. Following HCV clearance, significantly lower glycosylated hemoglobin was present both in patients with or without diabetes mellitus. Twenty-three (18.1%) patients exhibited adverse events, and each adverse event presented with an incidence of 0.8% to 3.1%. Neuropsychiatric symptoms were the most common. During treatment, 18 patients (14.2%) had alanine aminotransferase elevations consistent with more than grade 1 abnormalities, and none had signs of decompensation. Renal function remained unchanged.

CONCLUSION

The high SVR and excellent safety of LDV/SOF treatment for GT6 CHC patients suggest that LDV/SOF is a favorable option for treating GT6 CHC patients in Taiwan and Asia.

Improvement of hyperuricemia in chronic hepatitis C patients receiving directly acting antiviral agents

BACKGROUND AND AIM

Hepatitis C virus eradication via the use of antivirals ameliorates metabolic profiles. The changes in serum uric acid (SUA) levels in chronic hepatitis C patients who receive antivirals are not well understood. We aimed to address this issue by comparing the SUA changes before and after the achievement of a sustained virological response (which is defined as hepatitis C virus RNA seronegativity at 12 weeks after the end of treatment).

METHODS

Two hundred and thirteen sustained virological response patients who were treated by directly acting antivirals were consecutively enrolled. Pretreatment and post-treatment SUA levels were compared. Hyperuricemia was defined as a uric acid level > 7.0 mg/dL in men and > 6.0 mg/dL in women.

RESULTS

The SUA levels significantly decreased after treatment, as compared to the pretreatment levels (5.6 ± 1.5 vs 6.0 ± 1.7 mg/dL, respectively; P < 0.001). The proportion of hyperuricemia incidences significantly decreased after treatment (25.8% vs 35.7%, respectively; P = 0.001). The improvement was only observed in patients with a fibrosis-4 index (FIB-4) < 6.5 (25.7% vs 37.1%, P = 0.001) but not in those patients with a FIB-4 ≧ 6.5 (26.3% vs 28.9%, P = 1.00). A multivariate analysis revealed that the factor that was associated with significantly decreased SUA levels was FIB-4 < 6.5 (odds ratio [OR]/95% confidence interval [CI]: 3.22/1.04-9.95, P = 0.04) and estimated glomerular filtration rate < 60 mL/min/1.73 m² (OR/CI: 4.34/1.94-9.73, P < 0.001). There existed a trend of a higher proportion of patients with significant SUA improvement along with the decrement of FIB-4 (29.7%, 25%, and 10.5% in patients with FIB-4 < 3.25, 3.25-6.5, and > 6.5, respectively; trend P = 0.03).

CONCLUSIONS

SUA levels were significantly decreased in chronic hepatitis C patients after viral eradication. The improvement was particularly enhanced in patients with mild liver disease.

Polarization of granulocytic myeloid-derived suppressor cells by hepatitis C core protein is mediated via IL-10/STAT3 signalling

Myeloid-derived suppressor cells (MDSCs) have been described as suppressors of T-cell function in many malignancies. Impaired T-cell responses have been observed in patients with chronic hepatitis C virus infection (CHC), which is reportedly associated with the establishment of persistent HCV infection. Therefore, we hypothesized that MDSCs also play a role in chronic HCV infection. MDSCs in the peripheral blood of 206 patients with CHC and 20 healthy donors were analyzed by flow cytometry. Peripheral blood mononuclear cells (PBMCs) of healthy donors cultured with hepatitis C virus core protein (HCVc) were stimulated with or without interleukin 10 (IL-10). Compared to healthy donors and certain CHC patients with sustained viral response (SVR), CHC patients without SVR presented with a dramatic elevation of G-MDSCs with the HLA-DR^-/low CD33⁺ CD14^- CD11b⁺ phenotype in peripheral blood. The frequency of G-MDSCs in CHC patients was positively correlated with serum HCVc, and G-MDSCs were induced from healthy PBMCs by adding exogenous HCVc. Furthermore, we revealed a potential mechanism by which HCVc mediates G-MDSC polarization; activation of ERK1/2 resulting in IL-10 production and IL-10-activated STAT3 signalling. Finally, we confirmed that HCVc-induced G-MDSCs suppress the proliferation and production of IFN-γ in autologous T-cells. We also found that the frequency of G-MDSCs in serum was associated with CHC prognosis. HCVc maintains immunosuppression by promoting IL-10/STAT3-dependent differentiation of G-MDSCs from PBMCs, resulting in the impaired functioning of T-cells. G-MDSCs may thus be a promising biomarker for predicting prognosis of CHC patients.

Effectiveness and safety of elbasvir/grazoprevir therapy in patients with chronic HCV infection: Results from the Spanish HEPA-C real-world cohort

In randomized controlled trials of patients with chronic HCV infection, elbasvir/grazoprevir (EBR/GZR) demonstrated high cure rates and a good safety profile. This study assessed the effectiveness and safety of EBR/GZR, with and without ribavirin, in a real-world HCV patient cohort. HEPA-C is a collaborative, monitored national registry of HCV patients directed by the Spanish Association for the Study of the Liver and the Networked Biomedical Research Centre for Hepatic and Digestive Diseases. Patients entered into HEPA-C between December 2016 and May 2017, and treated with EBR/GZR with at least end-of-treatment response data, were included. Demographic, clinical and virologic data were analysed, and adverse events (AEs) recorded. A total of 804 patients were included in the study. The majority were male (57.9%), with a mean age of 60 (range, 19-92) years. Genotype (GT) distribution was GT 1, 86.8% (1a, 14.3%; 1b, 72.5%); GT 4, 13.2% and 176 patients (21.9%) were cirrhotic. Overall, among 588 patients with available data, 570 (96.9%) achieved sustained virologic response at 12 weeks post-treatment (SVR12). SVR12 rates by genotype were GT 1a, 97.7%; GT 1b, 98.6%; and GT 4, 98.1%. No significant differences in SVR12 according to fibrosis stage were observed. Eighty patients experienced an AE, resulting in treatment discontinuation in three. In this large cohort of patients with chronic HCV managed in a real-world setting in Spain, EBR/GZR achieved high rates of SVR12, comparable to those observed in randomized controlled trials, with a similarly good safety profile.

Mitochondrial Dysfunction and Signaling in Chronic Liver Diseases

Mitochondria regulate hepatic lipid metabolism and oxidative stress. Ultrastructural mitochondrial lesions, altered mitochondrial dynamics, decreased activity of respiratory chain complexes, and impaired ability to synthesize adenosine triphosphate are observed in liver tissues from patients with alcohol-associated and non-associated liver diseases. Increased lipogenesis with decreased fatty acid β-oxidation leads to the accumulation of triglycerides in hepatocytes, which, combined with increased levels of reactive oxygen species, contributes to insulin resistance in patients with steatohepatitis. Moreover, mitochondrial reactive oxygen species mediate metabolic pathway signaling; alterations in these pathways affect development and progression of chronic liver diseases. Mitochondrial stress and lesions promote cell death, liver fibrogenesis, inflammation, and the innate immune responses to viral infections. We review the involvement of mitochondrial processes in development of chronic liver diseases, such as nonalcoholic fatty, alcohol-associated, and drug-associated liver diseases, as well as hepatitis B and C, and discuss how they might be targeted therapeutically.