Factors influencing liver fibrosis and necroinflammation in HIV/HCV coinfection and HCV monoinfection

Progress in evaluating the status of hepatitis C infection based on the functional changes of hepatic stellate cells (Review)

Hepatitis C virus (HCV) infection is a global public health problem. Cirrhosis and hepatocellular carcinoma are the main causes of death in patients with chronic hepatitis C (CHC) infection. Liver fibrosis is an important cause of cirrhosis and end‑stage liver disease after CHC infection. Along with the course of infection, liver fibrosis exhibits a progressive exacerbation. Hepatic stellate cells (HSCs) are involved in both physiological and pathological processes of the liver. During the chronic liver injury process, the activated HSCs transform into myofibroblasts, which are important cells in the development of liver fibrosis. At present, HCV infection still lacks specific markers for the accurate detection of the disease condition and progression. Therefore, the present review focused on HSCs, which are closely related to HCV‑infected liver fibrosis, and analyzed the changes in the HSCs, including their surface‑specific markers, cytokine production, activation, cell function and morphological structure. The present review aimed to propose novel diagnostic markers, at both the cellular and molecular level, which would be of great significance for the timely diagnosis of the disease. According to this aim, the characteristic changes of HSCs during HCV infection were reviewed in the present article.

Eradication of HCV Infection with the Direct-Acting Antiviral Therapy in Renal Allograft Recipients

Hepatitis C virus (HCV) infection unfavorably affects the survival of both renal patients undergoing hemodialysis and renal transplant recipients. In this subset of patients, the effectiveness and safety of different combinations of interferon-free direct-acting antiviral agents (DAAs) have been analyzed in several small studies. Despite fragmentary, the available data demonstrate that DAA treatment is safe and effective in eradicating HCV infection, with a sustained virologic response (SVR) rates nearly 95% and without an increased risk of allograft rejection. This review article analyzes the results of most published studies on this topic to favor more in-depth knowledge of the readers on the subject. We suggest, however, perseverating in this update as the optimal DAA regimen may not be proposed yet, because of the expected arrival of newer DAAs and of the lack of data from large multicenter randomized controlled trials.

Steatosis Rates by Liver Biopsy and Transient Elastography With Controlled Attenuation Parameter in Clinical Experience of Hepatitis C Virus (HCV) and Human Immunodeficiency Virus/HCV Coinfection in a Large US Hepatitis Clinic

Background

Steatosis contributes to liver fibrosis in hepatitis C virus (HCV) and human immunodeficiency virus (HIV)/HCV coinfection. Liver biopsy (LB) is the reference standard for grading steatosis and staging fibrosis, yet recent advances in noninvasive modalities have largely supplanted LB, which may limit recognition of steatosis. We evaluated steatosis rates by LB and transient elastography (TE) with controlled attenuation parameter (CAP) among HCV-infected and HIV/HCV-coinfected patients in a US clinic.

Methods

Patients with chronic HCV infection during pretreatment evaluation by LB (n = 421; December 2001 through May 2014) and TE with CAP (n = 1157; May 2016 through May 2017) were included. Fibrosis and steatosis rates by LB and TE with CAP were stratified by HCV versus HIV/HCV coinfection status.

Results

Steatosis was not reported in 26.1% of LBs. Moderate to severe steatosis (grade ≥S2) was detected more often with CAP than with LB (in 24.0% vs 11.4% of patients, respectively). Median CAP values were higher in patients with HCV monoinfection than in those with coinfection (230 vs 215.5 dB/m, respectively; P < .001). With TE, the rate of advanced fibrosis (values F3–F4) was higher in HCV monoinfection than in coinfection (25.9% vs 14.8%, respectively; P <.001). With both LB and TE, advanced fibrosis (F3–F4) was significantly associated with moderate to severe steatosis (S2–S3) in HCV monoinfection compared with HIV/HCV coinfection (33.3% vs 4.4%, respectively for LB [P = 0.003] and 36.0% vs 29.0% for TE [P = 0.008]).

Conclusions

In patients with chronic HCV undergoing liver fibrosis staging, steatosis was detected more often with CAP than LB, with median CAP values higher in HCV monoinfection than HIV/HCV coinfection. Steatosis severity may be increasing in the modern HCV treatment era.

Incidence of HCV infection amongst HIV positive men who had sex with men and prevalence data from patients followed at the Infectious Diseases Clinic of Modena, Italy

BACKGROUND

Men who had sex with men (MSM) living with HIV are at higher risk of developing sexual transmitted diseases. This study reports two years incidence rate and prevalence of HCV in a cohort of HIV positive MSM.

METHODS

MSM HIV-positive outpatients negative to HCV-Ab at first observation entered a Kaplan-Meier model in order to assess the HCV infection incidence rate. Prevalence analysis was performed with MSM HIV-positive that were on follow-up at 2016. An MSM population HIV-negative served as control.

RESULTS

421 patients entered the incidence analysis. The incidence rate of HCV infection among MSM-HIV people was 0.44 per 100 patients-years (19 events). 40 out of 442 (9%) patients were HCV-positive (prevalence analysis); they were mostly genotype 1a and 3 with APRI score <0.7 (87.5%). Univariate analysis between MSM HIV-positive patients and MSM HIV-negative showed significant differences in the prevalence rate (9.0% vs 0.6%, P < 0.001) and median age (39 vs 47, P < 0.001).

CONCLUSION

Incidence and prevalence rate of HCV amongst MSM HIV-positive patients is higher than in other settings. Annual HCV-Ab screening for MSM HIV-positive patients should be enforced and early treatment of HCV recommended.

In vivo evidence that the cannabinoid receptor 2-63 RR variant is associated with the acquisition and/or expansion of HIV infection

OBJECTIVES

The aim of the study was to investigate whether the rs35761398 variants of the cannabinoid receptor 2 (CB2) gene may influence the acquisition of HIV infection and the clinical presentation of HIV/hepatitis C virus (HCV) coinfection.

METHODS

We compared 166 HIV/HCV-coinfected patients with 186 HCV-monoinfected patients, all with biopsy-proven chronic hepatitis (using the Ishak scoring system), naïve for anti-HCV treatment and tested for the CB2 rs35761398 polymorphism (using the TaqMan assay).

RESULTS

The HIV/HCV-coinfected patients were more frequently male (P < 0.002), were younger (P < 0.001), and had lower median BMI (P < 0.001) and HCV RNA (P < 0.05) and higher median aspartate aminotransferase (AST; P < 0.001), alanine aminotransferase (ALT; P < 0.001) and gamma glutamyl transferase (GGT; P < 0.001) levels than the HCV-monoinfected patients. The CB2 RR variant predominated in HIV/HCV-coinfected patients (45.8% vs. 31.2% in HCV-monoinfected patients; P < 0.001) and the CB2 QR variant in HCV-monoinfected patients (57.5% vs. 38.6% in HIV/HCV-coinfected patients; P < 0.00001), and the CB2 QQ variant was equally distributed. Focusing on patients with the CB2 QQ variant, the 26 HIV/HCV-coinfected patients, compared with the 21 HCV-monoinfected patients, showed less severe liver necroinflammation [lower histological activity index (HAI)] (P < 0.05). Of the patients with the CB2 RR variant, the 76 HIV/HCV-coinfected patients, compared with the 58 HCV-monoinfected patients, were more frequently male (P < 0.05), were younger (P < 0.001), and had a lower median body mass index (BMI; P < 0.001), a higher median AST level (P < 0.001), a higher mean HAI score (P < 0.05) and a higher rate of cases with severe steatosis (P = 0.05). In an analysis of variance (anova) of HCV/HIV-coinfected and HCV-monoinfected patient data, those with the CB2 RR variant (P = 0.003) and of male sex (P = 0.002) were more prevalent in the HCV/HIV-coinfected group.

CONCLUSIONS

There is the suggestion of a positive effect of the CB2 RR variant on HIV acquisition and/or spread, which is in accordance with previous in vitro observations.

Matrix stiffness regulate apoptotic cell death in HIV-HCV co-infected hepatocytes: Importance for liver fibrosis progression

HIV-HCV co-infection causes rapid progression of liver fibrosis. These outcomes to liver cirrhosis can be improved, but not stopped by specific antiviral therapies. Due to high significance of HIV-HCV interactions for morbidity and mortality in co-infected patients, our attention was attracted to the multi-component pathogenesis of fibrosis progression as the transition to end-stage liver disease development. In this study, we hypothesize that increased matrix stiffness enhances apoptosis in HCV-HIV-co-infected hepatocytes and that capturing of apoptotic bodies (AB) derived from these infected hepatocytes by hepatic stellate cells (HSC) drives the fibrosis progression. As the source of viruses, JFH1 (HCV genotype 2a) and HIV-1ADA (either purified or containing in infected macrophage supernatants) were chosen. Using Huh7.5-CYP (RLW) cells and primary human hepatocytes mono-infected with HCV and HIV or co-infected, we have shown that both HCV and HIV RNA levels were increased in co-infected cells, which was accompanied by hepatocyte apoptosis. This apoptosis was attenuated by azidothymidine treatment. The levels of both infections and apoptosis were more prominent in primary hepatocytes cultured on substrates mimicking fibrotic stiffness (24 kPa-stiff) compared to substrates mimicking healthy liver (2.4 kPa-soft). The engulfment of AB from pathogen-exposed hepatocytes activated pro-fibrotic mRNAs in HSC. Overall, the increased matrix stiffness is not only a consequence of liver inflammation/fibrosis, but the condition that further accelerates liver fibrosis development. This is attributed to the switching of HSC to pro-fibrotic phenotype by capturing of excessive amounts of apoptotic HCV- and HIV-infected hepatocytes.

Cannabinoid receptor 2-63 RR variant is independently associated with severe necroinflammation in HIV/HCV coinfected patients

Objective

This is the first study to analyze the impact of the rs35761398 variant of the CNR2 gene leading to the substitution of GLN (Q) of codon 63 of the cannabinoid receptor 2 (CB2) with ARG (R) on the clinical presentation of chronic hepatitis in HIV/HCV coinfected patients.

Methods

Enrolled in this study were 166 consecutive HIV/HCV coinfected patients, naïve for HCV treatment. A pathologist unaware of the patients’ condition graded liver fibrosis, necroinflammation (Ishak) and steatosis. All patients were screened for the CB2 rs35761398 polymorphism.

Results

Of the 166 HIV/HCV coinfected patients, 72.9% were males, 42.5% were infected with HCV-genotype-3 and 60.2% had been intravenous drug users. The median age was 40.6 years and the immunological condition good (median CD4⁺ cells/mm³ = 507, IQR: 398.0–669.5). Thirty-five (21.1%) patients were naive for ART and 131(78.9%) were on ART. The CB2-RR variant was detected in 45.8% of patients, QR in 38.6% and QQ in 15.7%. Patients with CB2-RR showed a necroinflammation score (HAI) ≥9 more frequently than those with CB2-QQ or CB2-QR (32.9% vs. 11.5% and 14.1%, respectively, p≤0.001). In the multivariate analysis, the CB2-RR variant (p = 0.03) and liver fibrosis were both identified as independent predictors of the entity of liver necroinflammation (p = 0.0001).

Conclusion

This study shows interesting interplay between the CB2-RR variant and liver necroinflammation in chronic hepatitis patients with HIV/HCV coinfection, an observation of clinical value that coincides with the interest in the use of the CB2 agonists and antagonists in clinical practice emerging from the literature.

MECHANISMS OF INTERACTION OF VIRAL CAUSATIVE AGENTS IN PATIENTS CO-INFECTED WITH HUMAN IMMUNODEFICIENCY AND HEPATITIS C VIRUSES

In patients infected with human immunodeficiency virus (HIV) in 20 - 30% of cases co-infection with hepatitis C virus (HCV) is observed, that is associated with common routes of transmission for these causative agents. The main cause of lethal outcome for co-infected patients is liver damage. Thus, analysis of mechanisms of mutual influence of HIV and HCV under the conditions of co-infection gains special attention, that can be examined from both standpoints of direct inter-molecular interaction of 2 viral causative agents, as well as from the position of their immune-mediated effect. Negative effect of HIV on the course of fibrosis process in liver during HCVinfection is associated with the feature of this virus to cause deep alteration in the immune system by direct damage of CD4+ cells, disruption of mechanisms of immunological memory, suppression of functions of liver fraction of NK and NKT, as well as its ability of co-receptor interaction with hepatocytes and stellate cells, enhancing progress of fibrosis alterations and HCV replication in liver. HCV is also established to effect replication of HIV, stimulate infection of macrophages with this virus. All these events facilitate the rise in lethality during HIV and HCV co-infection.

TM6SF2 E167K variant predicts severe liver fibrosis for human immunodeficiency/hepatitis C virus co-infected patients, and severe steatosis only for a non-3 hepatitis C virus genotype

AIM

To evaluate the impact of the Glu167Lys (E167K) transmembrane 6 superfamily member 2 (TM6SF2) variant on the biochemical and morphologic expression of liver lesions in human immunodeficiency virus (HIV)/hepatitis C virus (HCV) co-infected patients.

METHODS

The study comprised 167 consecutive patients with HIV/HCV coinfection and biopsy-proven chronic hepatitis. A pathologist graded liver fibrosis and necroinflammation using the Ishak scoring system, and steatosis using Kleiner’s scoring system. Patients were genotyped for TM6SF2 E167K (rs58542926) by real-time Polymerase chain reaction. The 167 patients, 35 therapy-naive and 132 receiving ART, were prevalently males (73.6%), the median age was 40.7 years and the immunological condition good (median CD4⁺ cells/mm³ = 505.5).

RESULTS

The 17 patients with the TM6SF2 E167K variant, compared with the 150 with TM6SF2-E/E, showed higher AST (P = 0.02) and alanine aminotransferase (P = 0.02) and higher fibrosis score (3.1 ± 2.0 vs 2.3 ± 1.5, P = 0.05). In a multivariate analysis, TM6SF2 E167K was independently associated with severe fibrosis. The same analysis showed that HCV-genotype 3, present in 42.2% of patients was an independent predictor of severe steatosis. The association of TM6SF2 E167K with severe steatosis, absent for the whole group of 167 patients, was re-evaluated separately for HCV-genotype 3 and non-3 patients: No factor was independently associated with severe steatosis in the HCV-genotype-3 subgroup, whereas an independent association was observed between severe steatosis and TM6SF2 E167K in non-3 HCV genotypes. No association between the TM6SF2 E167K variant and severe liver necroinflammation was observed.

CONCLUSION

In HIV/HCV coinfection the TM6SF2 E167K variant is an independent predictor of severe fibrosis, but appears to be independently associated with severe steatosis only for patients with a non-3 HCV genotype.

Impact of PNPLA3 variants on liver histology of 168 patients with HIV infection and chronic hepatitis C

This study analysed the impact of PNPLA3 variants on liver histology of 168 HIV/hepatitis C virus (HCV)-coinfected patients who were naïve for HCV treatment. A athologist unaware of the patients' condition graded liver fibrosis and necroinflammation (Ishak) and steatosis (Kleiner). Patients were tested for PNPLA3 variants and genotyped for the PNPLA3 rs738409 C to G variant underlying the I148M substitution. All were hepatitis B surface antigen negative and stated no alcohol abuse. The mean age was 40.6 (37.6-44.1) years, 72.6% were males, 42% had HCV genotype 3, 38.9% HCV genotype 1 and 79.2% were receiving highly active antiretroviral therapy. The 79 patients with the PNPLA3 p.148I/M or M/M variants more frequently showed severe steatosis (score 3-4) than the 89 with PNPLA3 p.148I/I (43% vs. 24.7%, p 0.001), whereas no difference was observed in the degree of necroinflammation or fibrosis. Compared with 112 patients with lower scores, 56 with severe steatosis showed higher body mass index (p 0.03), higher rate of HCV genotype 3 (55.6% vs. 35.2%, p 0.01), PNPLA3 p.148I/M or M/M (60.7% vs. 39.3%, p 0.01) and lower CD4(+) cells/mm(3) (514.00 (390.5-673.0) vs. 500.00 (399.0-627.0); p 0.002). At multivariate analysis, body mass index (p 0.01), HCV genotype 3 (p 0.006), CD4(+) cell count (p 0.005) and PNPLA3 p.148I/M or M/M variants (p 0.01) were found to be independent predictors of severe liver steatosis. The PNPLA3 p.148 I/M or M/M variants and CD4(+) cell count were the only independent predictors of severe steatosis in patients with HCV non-3 genotypes. This is the first study to show that among HIV/HCV-coinfected patients the PNPLA3 p.148I/M or M/M variant have substantially less impact on steatosis for those with HCV genotype 3 than non-genotype 3.

Increased expression and dysregulated association of restriction factors and type I interferon in HIV, HCV mono- and co-infected patients

Host restriction factors and type I interferon are important in limiting HIV and HCV infections, yet the role of HIV, HCV mono- and co-infection in regulating these antiviral genes expression is not clear. In this study, we measured the levels of TRIM5α, TRIM22, APOBEC3G, and IFN-α, -β mRNA expression in peripheral blood mononuclear cells of 43 HIV mono-infected, 70 HCV mono-infected and 64 HIV/HCV co-infected patients along with 98 healthy controls. We also quantified HIV and HCV viral loads in mono- and co-infected patients. The results showed that HCV, HIV mono- and co-infection differentially increased TRIM22, APOBEC3G, and IFN-α, -β mRNA expression while the mRNA expression of TRIMα was upregulated only by HCV-mono infection. HIV/HCV co-infection was associated with higher viral load, compared to either HIV or HCV mono-infection. Additionally, we showed TRIMα and TRIM22 positively correlated with IFN-α, -β, which could be dysregulated by HIV, HCV mono- and co-infection. Furthermore, we found TRIM22 negatively correlated with HCV viral load in mono-infected patients and APOBEC3G positively correlated with HCV viral load in co-infected patients. Collectively, our findings suggest the potential role of restriction factors in restricting HIV, HCV mono- and co-infection in vivo, which appears to be a therapeutic target for potential drug discovery.

Natural history and treatment of HCV/HIV coinfection: Is it time to change paradigms?

Evidence over the past decades have shown that HIV/HCV coinfected patients did not respond as well to HCV therapy as HCV mono-infected patients. However, these paradigms are being recently reassessed with the improvements of care for HIV and HCV patients. This article reviews these original paradigms and how the new data is impacting upon them. Treatment efficacy now appears comparable for HIV/HCV coinfected and HCV mono-infected patients, while liver fibrosis progression is increasingly similar in optimally managed patients. Additional importance of therapy is directed to drug-drug interactions and the impact of HCV reinfection, as well as the possibility of transmitted drug resistance.

Liver fibrosis in human immunodeficiency virus/hepatitis C virus coinfection: Diagnostic methods and clinical impact

Several non-invasive surrogate methods have recently challenged the main role of liver biopsy in assessing liver fibrosis in hepatitis C virus (HCV)-monoinfected and human immunodeficiency virus (HIV)/HCV-coinfected patients, applied to avoid the well-known side effects of liver puncture. Serological tests involve the determination of biochemical markers of synthesis or degradation of fibrosis, tests not readily available in clinical practice, or combinations of routine tests used in chronic hepatitis and HIV/HCV coinfection. Several radiologic techniques have also been proposed, some of which commonly used in clinical practice. The studies performed to compare the prognostic value of non-invasive surrogate methods with that of the degree of liver fibrosis assessed on liver tissue have not as yet provided conclusive results. Each surrogate technique has shown some limitations, including the risk of over- or under-estimating the extent of liver fibrosis. The current knowledge on liver fibrosis in HIV/HCV-coinfected patients will be summarized in this review article, which is addressed in particular to physicians involved in this setting in their clinical practice.

Treatment of chronic hepatitis C in patients with HIV/HCV coinfection

Hepatitis C virus (HCV) infection is one of the most frequent causes of comorbidity and mortality in the human immunodeficiency virus (HIV) population, and liver-related mortality is now the second highest cause of death in HIV-positive patients, so HCV infection should be countered with adequate antiviral therapy. In 2011 began the era of directly acting antivirals (DAAs) and the HCV NS3/4A protease inhibitors telaprevir and boceprevir were approved to treat HCV-genotype-1 infection, each one in combination with pegylated interferon alfa (Peg-IFN) + ribavirin (RBV). The addition of the first generation DAAs, strongly improved the efficacy of antiviral therapy in patients with HCV-genotype 1, both for the HCV-monoinfected and HIV/HCV coinfected, and the poor response to Peg-IFN + RBV in HCV/HIV coinfection was enhanced. These treatments showed higher rates of sustained virological response than Peg-IFN + RBV but reduced tolerability and adherence due to the high pill burden and the several pharmacokinetic interactions between HCV NS3/4A protease inhibitors and antiretroviral drugs. Then in 2013 a new wave of DAAs arrived, characterized by high efficacy, good tolerability, a low pill burden and shortened treatment duration. The second and third generation DAAs also comprised IFN-free regimens, which in small recent trials on HIV-positive patients have shown comforting preliminary results in terms of efficacy, tolerability and adherence.

Intestinal barrier dysfunction in HIV infection: pathophysiology, clinical implications and potential therapies

INTRODUCTION

Current pathogenetic aspects on HIV infection highlight the importance of a chronic immune activation ultimately leading to T lymphocyte homeostasis disruption and immune deregulation associated with disease manifestations and progression. It is widely accepted that this continuous immune activation in HIV infection is principally driven by the phenomenon of pathological microbial translocation (MT).

METHODS

Review of the literature on the role of intestinal barrier dysfunction in HIV infection, with emphasis on the implicated pathophysiological mechanisms, clinical implications and potentially effective therapeutic interventions.

FINDINGS

MT in HIV infection is promoted by a multifactorial disruption of all major levels comprising the intestinal barrier defense. Specifically, HIV infection disrupts the integrity of the intestinal biological (quantitative and qualitative alterations of gut microecology, overgrowth of pathogenic bacteria), immune (depletion of CD4(+) T cells, especially Th17 cells, increased CD4+ FoxP3+ Tregs, decreased mucosal macrophages phagocytic capacity, development of intestinal proinflammatory milieu) and mechanical barrier (enterocytes' apoptosis, disruption of tight junctions). Intestinal barrier dysfunction allows the passage of microbes and immunostimulatory bioproducts from the gut lumen first in the lamina propria and thereafter in the systemic circulation, thus continuously promoting a local and systemic inflammatory response. This chronic immune activation is associated with HIV disease progression, suboptimal response to HAART and development of non-AIDS comorbidities.

CONCLUSIONS

We have reached a point where the effective control of HIV viremia by HAART should be combined with emerging pharmacological approaches aiming at the restoration of the intestinal barrier, targeting its diverse levels of structure and function. Elimination of the MT phenomenon would mitigate its effect on immune homeostasis, which might improve the prognosis of the HIV-infected patient in terms of morbidity and mortality.

Computational models of liver fibrosis progression for hepatitis C virus chronic infection

BACKGROUND

Chronic infection with hepatitis C virus (HCV) is a risk factor for liver diseases such as fibrosis, cirrhosis and hepatocellular carcinoma. HCV genetic heterogeneity was hypothesized to be associated with severity of liver disease. However, no reliable viral markers predicting disease severity have been identified. Here, we report the utility of sequences from 3 HCV 1b genomic regions, Core, NS3 and NS5b, to identify viral genetic markers associated with fast and slow rate of fibrosis progression (RFP) among patients with and without liver transplantation (n = 42).

METHODS

A correlation-based feature selection (CFS) method was used to detect and identify RFP-relevant viral markers. Machine-learning techniques, linear projection (LP) and Bayesian Networks (BN), were used to assess and identify associations between the HCV sequences and RFP.

RESULTS

Both clustering of HCV sequences in LP graphs using physicochemical properties of nucleotides and BN analysis using polymorphic sites showed similarities among HCV variants sampled from patients with a similar RFP, while distinct HCV genetic properties were found associated with fast or slow RFP. Several RFP-relevant HCV sites were identified. Computational models parameterized using the identified sites accurately associated HCV strains with RFP in 70/30 split cross-validation (90-95% accuracy) and in validation tests (85-90% accuracy). Validation tests of the models constructed for patients with or without liver transplantation suggest that the RFP-relevant genetic markers identified in the HCV Core, NS3 and NS5b genomic regions may be useful for the prediction of RFP regardless of transplant status of patients.

CONCLUSIONS

The apparent strong genetic association to RFP suggests that HCV genetic heterogeneity has a quantifiable effect on severity of liver disease, thus presenting opportunity for developing genetic assays for measuring virulence of HCV strains in clinical and public health settings.

Advances in the treatment of hepatitis B virus/hepatitis C virus coinfection

INTRODUCTION

Patients with chronic hepatitis B virus (HBV)/hepatitis C virus (HCV) coinfection are at a high risk of developing liver cirrhosis and hepatocellular carcinoma, and consequently, warrant effective treatment.

AREAS COVERED

Effective treatment should eradicate HCV infection and inhibit HBV replication but without serious adverse reactions. Careful evaluation of disease progression, predominance of one virus over another, comorbidities and concomitant hepatitis delta virus and/or HIV infection are essential for better therapy choices. In the case of HCV predominance, Peg-interferon plus ribavirin with or without a first-generation directly acting antiviral (DAA) should be the first choice, but future treatments will be DAA-based and interferon-free. In the case of HBV predominance, tenofovir or entecavir should be part of treatment. Patients should be closely monitored for early identification and treatment of HCV or HBV reactivation.

EXPERT OPINION

High potency and high genetic barrier nucleos(t)ide analogues to inhibit HBV replication have been used for years, with no urgency for new drugs. Several DAAs for interferon-free therapy for HCV eradication will be available in the near future. We hope that the high cost of these drugs will not be a limitation to their use in developing countries. Further investigation of HBV/HCV interaction is needed before and during the administration of new therapies.

Asunaprevir, a protease inhibitor for the treatment of hepatitis C infection

According to the World Health Organization, approximately 150 million people worldwide are chronic carriers of hepatitis C virus (HCV). HCV infection can evolve into cirrhosis of the liver and its complications, which are ultimately responsible for more than 350,000 deaths every year. Antiviral therapy, when successful, is able to decrease the rate of progression and increase survival. Two types of therapies are currently available, ie, interferon-based therapies and interferon-free ones. The latter have several advantages in terms of safety and tolerability, and could be used even in the most advanced stages of the disease. However, their use is restricted to some viral genotypes (genotype 2 and 3) and they are expensive. Several molecules are in an advanced phase of development. This review deals with the pharmacokinetics, pharmacodynamics, tolerability, and safety of asunaprevir, an inhibitor of HCV nonstructural 3 protease. Asunaprevir exerts optimal in vitro activity particularly against HCV genotypes 1 and 4, and its pharmacokinetic profile enables twice daily administration. The drawback of asunaprevir, and of all protease inhibitors, is its low barrier to resistance. Consequently, it is used in association with other drugs to prevent resistance. Specifically, when combined with daclatasvir, an NS5A inhibitor, asunaprevir results in a very high rate of viral eradication in both treatment-naïve and treatment-experienced patients, with a sustained virological response rate of 80%-90%. Tolerability is fair; in fact, asunaprevir is associated with a transient increase in aminotransferase levels, which is mild in most cases. In conclusion, asunaprevir is a good candidate component of interferon-free combinations and may revolutionize the treatment of chronic HCV infection in the near future.

Anti-hepatitis C virus treatment may prevent the progression of liver fibrosis in non-responder human immunodeficiency virus/hepatitis C virus coinfected patients

Aim

To evaluate changes in liver histology in patients with human immunodeficiency virus/hepatitis C virus coinfection non-responders to a suboptimal Interferon + Ribavirine regimen.

Materials and methods

We investigated 49 patients with two sequential liver biopsies: 18 were non-responders to Interferon + Ribavirine treatment (Group hepatitis C virus Rx) administered after the 1st liver biopsy who underwent a 2nd liver biopsy after a median period of 3.92 year and 31 were patients who remained untreated for hepatitis C virus disease (Group hepatitis C virus untreated) after the 1st liver biopsy because of refusal and underwent a 2nd liver biopsy after a median period of 5.05-years. Most patients in both groups were under highly active antiretroviral therapy. At the time of 1st liver biopsy similar degrees of necro-inflammation, fibrosis and steatosis were observed in both groups. Changes in liver lesions between 1st and 2nd liver biopsys were adjusted for different intervals between liver biopsys by a mathematic formula.

Results

Liver fibrosis did not change in 88.9% of patients in Group hepatitis C virus Rx and in 77.4% in Group hepatitis C virus untreated. A marked deterioration in liver fibrosis was observed in 5 (16%) patients in Group hepatitis C virus untreated and in none in Group hepatitis C virus treated. Necro-inflammation and steatosis remained substantially unchanged in both groups.

Conclusion

Liver histology remained substantially unchanged in human immunodeficiency virus/hepatitis C virus patients non-responder to anti-hepatitis C virus therapy over 4 years observation, suggesting an effective anti-hepatitis C virus early treatment for all hepatitis C virus/human immunodeficiency virus coinfected patients who can reasonably tolerate therapy.