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

Short- and Long-Term Immunological Responses in Chronic HCV/HIV Co-Infected Compared to HCV Mono-Infected Patients after DAA Therapy

Background: Direct-acting antivirals (DAAs) treatment, although highly efficacious for the treatment of hepatitis C virus (HCV) infection, may not completely reconstitute the HCV-mediated dysregulated immune system, especially in patients co-infected with human immunodeficiency virus (HIV) and HCV. Objectives: We aimed to evaluate the impact of HCV eradication following DAA therapy on the immune system and liver disease improvement through comparative monitoring of 10 HCV mono-infected and 10 HCV/HIV co-infected patients under combined antiretroviral therapy (cART). Early and late longitudinal phenotypic changes in peripheral blood mononuclear cell (PBMC) subsets, T-cell activation, differentiation and exhaustion, as well as inflammatory biomarkers, indoleamine 2-3 dioxygenase (IDO) activity, and liver stiffness, APRI and FIB-4 scores were assessed. Materials and Methods: Samples were obtained at baseline (T0), week 1 (T1), week 2 (T2), week 12 (T3, end of treatment, EOT), and month 9 (T4, end of follow-up, 36 weeks post EOT). Results: All patients achieved a sustained virological response (SVR 12) after DAA treatment. Overall, changes of the T-cell immune phenotypes were greater in HCV/HIV co-infected than in HCV mono-infected, due to an increase in CD4+ and CD8+ T-cell percentages and of CD8+ T-cell activation and memory markers, in particular at the end of follow-up. On the other end, HCV mono-infected showed changes in the activation profile and in the memory CD4+ T-cell compartment. In HCV/HIV co-infected, a decrease in the IDO activity by DAA treatment was observed; conversely, in HCV mono-infected, it resulted unmodified. Regarding inflammatory mediators, viral suppression was associated with a reduction in IP-10 levels, while interferon regulatory factor (IRF)-7, interferon (IFN)-β, and interferon (IFN)-γ levels were downregulated during therapy and increased post therapy. A decrease in liver stiffness, APRI, and FIB-4 scores was also observed. Conclusions: Our study suggests that, although patients achieved HCV eradication, the immune activation state in both HCV mono-infected and HCV/HIV co-infected patients remains elevated for a long time after the end of DAA therapy, despite an improvement of liver-specific outcomes, meanwhile highlighting the distinct immunophenotypic and inflammatory biomarker profile between the groups of patients.

Resistance detection and re-treatment options in hepatitis C virus-related chronic liver diseases after DAA-treatment failure

BACKGROUND

Introduced in 2013-2014, the second- and third-wave directly acting antivirals (DAAs) have strongly enhanced the efficacy and tolerability of anti-HCV treatment, with a sustained virological response (SVR) in 90-95% of cases treated. The aim of this paper was to focus on the type and prevalence of viral strains with a reduced sensitivity to DAAs and on treatment choices for DAA-experienced patients.

METHODS

The Medline was searched for "HCV infection", "HCV treatment", "Directly acting antivirals","HCV resistance".

RESULTS

Most patients who did not achieve an SVR have been found to be infected with HCV mutant strains with a reduced susceptibility to these drugs. These mutants occur frequently in the NS5A region, with a moderate frequency in the NS3/4A regions and rarely in the NS5B region. Treatment-induced mutants resistant to NS5A DAAs persist for years after treatment discontinuation, whereas those resistant to the NS3 DAAs have a shorter duration.

CONCLUSIONS

Patients who have failed HCV treatment with DAA agents have several re-treatment options, but re-treatment selection may be intricate and resistance testing is recommended to optimize this choice. It is, therefore, important to bear in mind that the correct determination of HCV genotype and subtype and the identification of RASs are essential elements for choosing the optimal re-treatment. It is supposed that it is useful to give readers some other suggestions regarding therapeutic reprocessing.

The lived experience of interferon-free treatments for hepatitis C: A thematic analysis

BACKGROUND

International discourse concerning the evolution in hepatitis C virus (HCV) therapy has tended to focus on improving outcomes, shortened treatment length and reduced side-effects of interferon-free regimens. How these treatments are being understood and experienced by the people receiving them has so far been overlooked. This study therefore aimed to explore the lived experience of individuals taking interferon-free HCV therapies.

METHODS

Data were generated through 16 semi-structured interviews with a purposive sample of eight participants, recruited from a university hospital in Scotland. The interviews took place between June 2015 and March 2016, before and after a period of interferon-free HCV treatment. The data were interrogated using a thematic analysis, underpinned by social phenomenological theory.

RESULTS

Three overriding themes were identified. 'Expectations and realisations' characterised the influence that interferon continued to cast over interferon-free treatment, contrasting the practicalities of taking interferon-free therapy with preconceived notions. 'An honour and a pleasure' portrayed a positive experience of an undemanding therapy, yet among those with a history of drug use, was also positioned as a privilege, associated with feelings of luck and guilt. 'Treatment needs' illustrated the strategies participants used to search for treatment efficacy, and the value those with a significant history of drug use placed on support. One nonconforming case is then discussed to enhance rigour and trustworthiness.

CONCLUSION

This is the first qualitative exploration of the experience of interferon-free HCV treatment reported globally. The results from this study suggest a cultural lag exists between the pharmacological developments which have been witnessed, and societal understandings of them. This has implications for the way services meet the needs of, and offer therapy to, HCV positive individuals.

Correlates of infection and molecular characterization of blood-borne HIV, HCV, and HBV infections in HIV-1 infected inmates in Italy: An observational cross-sectional study

Coinfection of blood-borne hepatitis B and hepatitis C viruses (HBV and HCV, respectively) in human immunodeficiency virus type 1 (HIV-1)-positive individuals frequently occurs in inmate population and peculiar viral strains and patterns of virological markers may be observed.Plasma from 69 HIV-1-positive inmates was obtained from 7 clinical centers connected with correctional centers in different towns in Italy. HIV, HBV, and HCV markers were tested by commercial assays. Virus genotyping was carried out by sequencing the protease and reverse transcriptase-encoding region (PR-RT region) for HIV and a region encompassing the NS5B gene for HCV and subsequent phylogenetic analysis.Twelve over 14 HIV-subtyped inmates were infected with HIV-1 subtype B strains. The 2 non-B strains belonged to subtype G and CRF02_AG, in an Italian and a Gambian patient, respectively. Variants carrying the K103N and Y181C resistance mutations to non-nucleoside reverse transcriptase inhibitors (NNRTIs) were found in 2 out of 9 patients naive for combined antiretroviral therapy (cART) (22.2%). Most HIV-positive patients (92.8%) showed evidence of past or present HBV and/or HCV infection. Prevalence of HBV and HCV was 81.2% for both viruses, whereas prevalence of HBV/HCV coinfection was 69.6%. A significantly higher presence of HCV infection was found in Italians [odds ratio (OR) 11.0; interval 1.7-80.9] and in drug users (OR 27.8; interval 4.9-186.0). HCV subtypes were determined in 42 HCV or HBV/HCV-coinfected individuals. HCV subtypes 1a, 3a, 4d, and 1b were found in 42.9%, 40.5%, 14.3%, and 2.4% of inmates, respectively. Low titers of HBV DNA in HBV DNA positive subjects precluded HBV subtyping.The high prevalence of HBV and HCV coinfections in HIV-infected inmates, as well as the heterogeneity of HIV and HCV subtypes suggest the need to adopt systematic controls in prisons to monitor both the burden and the genetic forms of blood-borne viral infections, in order to apply targeted therapeutic interventions.

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.

The hepatitis C revolution part 2: difficult-to-treat groups and experimental approaches

PURPOSE OF REVIEW

Novel direct-acting antiviral (DAA) agents are highly effective in the treatment of hepatitis C, achieving unprecedented rates of sustained virological response, a functional cure. However, a significant minority of patients belong to 'difficult-to-treat' groups, in which efficacy of DAAs appears less robust. The review article aims to discuss additional treatment strategies which may be employed in these patient cohorts, as well as evidence for the potential role of experimental DAAs.

RECENT FINDINGS

Patients with genotype 3 infection have consistently lower rates of virological clearance following DAA therapy when compared with other genotypes. However, in combination with sofosbuvir, the novel nonstructural protein 5A inhibitor daclatasvir has demonstrated high efficacy in the treatment of noncirrhotic genotype 3 infection. Recent data from phase 2 and 3 clinical studies support the use of currently approved DAA regimens in the treatment of patients with hepatitis C virus and human immunodeficiency virus (HIV) coinfection. Sustained virological response rates in coinfected patients are analogous to those observed in monoinfection, such that HIV infection itself does not pose a barrier to DAA efficacy. In posttransplant populations, DAAs have again shown great potential, with trial data validating use of sofosbuvir/ledipasvir.

SUMMARY

Unmet need persists in certain subsets of the hepatitis C patient population. The arrival on scene of novel DAAs is likely to further expand the repertoire of available therapy for these 'difficult-to-treat' groups.

APASL consensus statements and recommendation on treatment of hepatitis C

The Asian-Pacific Association for the Study of the Liver (APASL) convened an international working party on the "APASL consensus statements and recommendation on management of hepatitis C" in March, 2015, in order to revise "APASL consensus statements and management algorithms for hepatitis C virus infection (Hepatol Int 6:409-435, 2012)". The working party consisted of expert hepatologists from the Asian-Pacific region gathered at Istanbul Congress Center, Istanbul, Turkey on 13 March 2015. New data were presented, discussed and debated to draft a revision. Participants of the consensus meeting assessed the quality of cited studies. Finalized recommendations on treatment of hepatitis C are presented in this review.

The discovery of sofosbuvir: a revolution for therapy of chronic hepatitis C

INTRODUCTION

Hepatitis C virus (HCV) infection is a worldwide health problem, whose management has been revolutionized after the availability of sofosbuvir, a direct-acting antiviral (DAAs). Sofosbuvir is a HCV NS5B polymerase inhibitor. Antiviral regimens including sofosbuvir are associated with success rates >90%, even in the case of "difficult-to-treat" patients such as subjects with liver cirrhosis as well as prior null response to IFN and ribavirin.

AREAS COVERED

This drug discovery case history focuses on the pre-clinical and clinical development of sofosbuvir. The authors analyze all of the main steps leading to the global approval of sofosbuvir. The paper also highlights the encouraging data from the subsequent trials wherein sofosbuvir was tested in combination with other DAAs (IFN- and often ribavirin-free regimens) and from first real life studies.

EXPERT OPINION

Sofosbuvir is a very powerful weapon in the new armamentarium against HCV. Thanks to its valuable features including its pangenotypic activity, once-daily oral administration, its excellent tolerability, and safety profile, it represents the backbone of several effective regimens, in combination with IFN or with other DAAs (IFN-free therapies). Regimens including sofosbuvir have quickly become the touchstone for all the novel anti-HCV treatments.

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.

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.

Hepatitis C virus markers in infection by hepatitis C virus: In the era of directly acting antivirals

About 130-170 million people are infected with the hepatitis C virus (HCV) worldwide and more than 350000 people die each year of HCV-related liver diseases. The combination of pegylated interferon (Peg-IFN) and ribavirin (RBV) was recommended as the treatment of choice for chronic hepatitis C for nearly a decade. In 2011 the directly acting antivirals (DAA) HCV NS3/4A protease inhibitors, telaprevir and boceprevir, were approved to treat HCV-genotype-1 infection, each in triple combination with Peg-IFN and RBV. These treatments allowed higher rates of SVR than the double Peg-IFN + RBV, but the low tolerability and high pill burden of these triple regimes were responsible for reduced adherence and early treatment discontinuation. The second and third wave DAAs introduced in 2013-2014 enhanced the efficacy and tolerability of anti-HCV treatment. Consequently, the traditional indicators for disease management and predictors of treatment response should be revised in light of these new therapeutic options. This review article will focus on the use of the markers of HCV infection and replication, of laboratory and instrumental data to define the stage of the disease and of predictors, if any, of response to therapy in the DAA era. The article is addressed particularly to physicians who have patients with hepatitis C in care in their everyday clinical practice.

New treatment strategies for hepatitis C infection

Hepatitis C infection can lead to cirrhosis and hepatocellular carcinoma and it is an important cause of mortality and morbidity. Achieving a sustained virological response has been the major aim for decades. Interferon treatment was the primarily developed therapy against the infection. Addition of the guanosine analog ribavirin to stop viral RNA synthesis increased the response rates as well as the adverse effects of the treatment. The increasing demands for alternative regimens led to the development of direct-acting antivirals (DAAs). The approval of sofosbuvir and simeprevir signaled a new era of antiviral treatment for hepatitis C infection. Although the majority of studies have been performed with DAAs in combination with interferon and resulted in a decrease in treatment duration and increase in response rates, the response rates achieved with interferon-free regimens provided hope for patients ineligible for therapy with interferon. Most DAA studies are in phase II leading to phase III. In the near future more DAAs are expected to be approved. The main disadvantage of the therapy remains the cost of the drugs. Here, we focus on new treatment strategies for hepatitis C infection as well as agents targeting hepatitis C virus replication that are in clinical development.

Dual antiviral therapy for HIV and hepatitis C - drug interactions and side effects

INTRODUCTION

Roughly 20% of HIV-positive persons worldwide are coinfected with hepatitis C virus (HCV). The recent advent of direct-acting antivirals (DAA) that cure most hepatitis C patients has attracted much attention. Knowledge on drug interactions between DAA and antiretrovirals (ARV) may allow maximizing antiviral efficacy while minimizing drug-related toxicities.

AREAS COVERED

We review the most frequent side effects and clinically significant drug interactions between DAA and ARV. We further discuss how they can be prevented and managed in HIV/HCV-coinfected patients.

EXPERT OPINION

The safety profile of current DAA and the most recently approved ARV is quite favorable. Interactions between DAA and ARV could be frequent in clinical practice. The most common drug interactions affect drug metabolism by inducing or inhibiting the cytochrome P450 system, leading to abnormal drug exposures. Throughout this mechanism HCV and HIV protease inhibitors interact, especially when co-formulated with ritonavir as a pharmacoenhancer, and non-nucleoside HCV and HIV polymerase inhibitors. In contrast, HIV and HCV nucleos(t)ide polymerase inhibitors, and most HCV NS5A inhibitors (i.e., ledipasvir) and HIV integrase inhibitors (i.e., dolutegravir), do not or only marginally affect CYP450, and therefore are free of significant drug interactions. Exposure to HIV and HCV nucleos(t)ide analogues (i.e., tenofovir and sofosbuvir, respectively) is subject to induction/inhibition of drug transporters (i.e., P-glycoprotein).