Impact of HIV on host-virus interactions during early hepatitis C virus infection

Hepatitis co-infection in paediatric HIV: progressing treatment and prevention

PURPOSE OF REVIEW

To analyse the main evidence and recommendations for the management of hepatitis co-infection in children living with HIV.

RECENT FINDINGS

We analysed available data pertaining to the natural history of liver disease and treatment of co-infected children.

SUMMARY

Viral hepatitis co-infection in people living with HIV (PLHIV) is a global problem owing to the shared routes of transmission, particularly in areas of high endemicity for the three viruses. Viral hepatitis co-infection can accelerate liver disease progression and increase morbidity and mortality, even in patients on suppressive antiretroviral treatment (ART). Viral hepatitis should be routinely screened in PLHIV and, once diagnosed with viral hepatitis, PLHIV should be closely monitored for liver disease progression and complications. Children living with HIV-HBV co-infection should be treated with ART containing agents which are active against both viruses. Children living with HIV-HCV co-infection should receive directly acting antivirals (DAA) to eradicate HCV infection. Prevention measures to reduce vertical and horizontal transmission of HBV and HCV (anti-HBV vaccination and immunoglobulins, anti-HBV treatment in pregnancy, anti-HCV DAAs in people of childbearing age, avoiding blood contact, sexual barrier precautions) should be adopted and encouraged, particularly in high endemicity countries.

Treatment Outcomes of HCV Infection in People Living with HIV: A Case Series from a Single Center in Korea

BACKGROUND

Limited information is available on the clinical course and treatment outcomes of human immunodeficiency virus (HIV) and hepatitis C virus (HCV) coinfection in Korea.

MATERIALS AND METHODS

A retrospective case series was conducted of patients with HIV-HCV coinfection who received interferon (IFN)-based or direct-acting antiviral (DAA) treatment for HCV at a tertiary care hospital between 2000 and 2023. Early virological response (EVR) was defined as a 2-log reduction in HCV RNA levels or undetectable HCV RNA levels at treatment week 12. A sustained virologic response (SVR) was defined as undetectable HCV RNA at 12 weeks after treatment completion.

RESULTS

Of the 33 patients with HIV-HCV coinfection, 19 received anti-HCV treatment, of whom 12 received IFN-based treatment and 10 received DAA treatment. The median age at the time of anti-HCV treatment was 49 years (interquartile range, 42-57 years) and 15 patients (79%) were male. Of the 12 patients who received IFN-based anti-HCV treatment, 10 showed EVR and 8 achieved SVR. However, 2 patients who achieved SVR experienced recurrence of HCV infection during follow-up; therefore, the overall success rate of IFN-based treatment was 50% (6/12). All 10 patients (including 3 in whom IFN-based treatment failed) who received DAA treatment (5 with previous anti-HCV treatment and 5 treatment-naïve), achieved SVR and did not experience recurrence of HCV infection during follow-up; therefore, the overall success rate of DAA treatment was 100%.

CONCLUSION

In Korean patients with HIV-HCV coinfection, treatment outcomes were better with DAA treatment than with IFN-based treatment.

Identification and functional characterization of laminin receptor in the mud crab, Scylla paramamosain, in response to MCDV-1 challenge

Laminin receptor (LR), which mediating cell adhesion to the extracellular matrix, plays a crucial role in cell signaling and regulatory functions. In the present study, a laminin receptor gene (SpLR) was cloned and characterized from the mud crab (Scylla paramamosain). The full length of SpLR contained an open reading frame (ORF) of 960 bp encoding 319 amino acids, a 5' untranslated region (UTR) of 66 bp and a 3' UTR of 49 bp. The predicted protein comprised two Ribosomal-S2 domains and a 40S-SA-C domain. The mRNA of SpLR was highly expressed in the gill, followed by the hepatopancreas. The expression of SpLR was up-regulated after mud crab dicistrovirus-1(MCDV-1) infection. Knocking down SpLR in vivo by RNA interference significantly down-regulated the expression of the immune genes SpJAK, SpSTAT, SpToll1, SpALF1 and SpALF5. This study shown that the expression level of SpToll1 and SpCAM in SpLR-interfered group significantly increased after MCDV-1 infection. Moreover, silencing of SpLR in vivo decreased the MCDV-1 replication and increased the survival rate of mud crabs after MCDV-1 infection. These findings collectively suggest a pivotal role for SpLR in the mud crab's response to MCDV-1 infection. By influencing the expression of critical innate immune factors and impacting viral replication dynamics, SpLR emerges as a key player in the intricate host-pathogen interaction, providing valuable insights into the molecular mechanisms underlying MCDV-1 pathogenesis in mud crabs.

Functional HIV-1/HCV cross-reactive antibodies isolated from a chronically co-infected donor

Despite prolific efforts to characterize the antibody response to human immunodeficiency virus type 1 (HIV-1) and hepatitis C virus (HCV) mono-infections, the response to chronic co-infection with these two ever-evolving viruses is poorly understood. Here, we investigate the antibody repertoire of a chronically HIV-1/HCV co-infected individual using linking B cell receptor to antigen specificity through sequencing (LIBRA-seq). We identify five HIV-1/HCV cross-reactive antibodies demonstrating binding and functional cross-reactivity between HIV-1 and HCV envelope glycoproteins. All five antibodies show exceptional HCV neutralization breadth and effector functions against both HIV-1 and HCV. One antibody, mAb688, also cross-reacts with influenza and coronaviruses, including severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). We examine the development of these antibodies using next-generation sequencing analysis and lineage tracing and find that somatic hypermutation established and enhanced this reactivity. These antibodies provide a potential future direction for therapeutic and vaccine development against current and emerging infectious diseases. More broadly, chronic co-infection represents a complex immunological challenge that can provide insights into the fundamental rules that underly antibody-antigen specificity.

Factors Associated with Spontaneous Clearance of Recently Acquired Hepatitis C Virus among HIV-Positive Men in Brazil

INTRODUCTION

The objective of the present study was to describe the clinical and epidemiological aspects of recently acquired hepatitis C virus (HCV) infection and the frequency of its spontaneous clearance in a people living with the human immunodeficiency virus (PLWH) cohort.

METHODS

We reviewed the medical records from all PLWH at the human immunodeficiency virus (HIV) outpatient reference clinic affiliated with the University of São Paulo, Brazil, and identified, by immunoassays and RNA-PCR individuals who acquired HCV infection between January 2015 and December 2017. The factors associated with subsequent spontaneous clearance of the infection in this group were identified and analyzed.

RESULTS

Among 3143 PLWH individuals, 362 (11.5%) were coinfected with HCV. Forty-eight (13.2%) of these subjects first became HCV-positive between January 2015 and December 2017. Spontaneous HCV clearance was documented in 23 individuals (47.9%). The majority of this latter group were male (83.3%), and the median age was 31 years (23-39). The main risk group for HCV acquisition was men who had sex with men (MSM) (89.5%). In a multivariate analysis, only an elevated CD4+ T lymphocyte count at the time of seroconversion was found to be associated with subsequent HCV clearance (p = 0.025).

CONCLUSIONS

In HIV-infected individuals in Sao Paulo, Brazil, most cases of recent HCV transmission were by sexual exposure. In PLWH, particularly in MSM, the individual's CD4+ T lymphocyte count is a determinant of whether an acquired HCV infection will be prolonged or will spontaneously clear.

Causes and outcomes of hepatic fibrosis in persons living with HIV

PURPOSE OF REVIEW

The epidemiology of liver disease in people living with HIV has evolved since the arrival of effective hepatitis C virus (HCV) treatment. Nonalcoholic fatty liver disease (NAFLD) in HIV patients is highly prevalent while hepatitis D, hepatitis E, and occult hepatitis B remain underappreciated. We discuss mechanisms of fibrosis in HIV and review clinical outcomes of HIV-associated liver diseases.

RECENT FINDINGS

HIV-HCV co-infection is receding as a cause of progressive liver disease, but fibrosis biomarkers after HCV treatment remain elevated. Antiretroviral therapy (ART) with anti-hepatitis B virus (HBV) activity promotes stable liver disease, but oversimplifying ART regimens in unrecognized suppressed HBV may lead to activation of HBV. A high prevalence of fibrosis and rapid progression of fibrosis are seen in HIV-associated NAFLD, with visceral fat as a major risk factor. Newer ART such as integrase strand inhibitors may have limited intrinsic hepatoxicity but do increase weight, which may secondarily lead to hepatic steatosis. Promising therapies for HIV-associated NAFLD include tesamorelin and CCR5 blockade agents.

SUMMARY

Our understanding of the natural history and pathogenesis of liver diseases in HIV has advanced and adapted to the changing landscape of liver disease in this population. Future research should evaluate long-term clinical and histological outcomes, prevention strategies, and treatment options to improve morbidity and mortality in HIV-related liver diseases.

Mathematical modeling of HIV-HCV co-infection model: Impact of parameters on reproduction number

Background: Hepatitis C Virus (HCV) and Human Immunodeficiency Virus (HIV) are both as classified blood-borne viruses since they are transmitted through contact with contaminated blood. Approximately 1.3 million of the 2.75 million global HIV/HCV carriers inject drugs (PWID). HIV co-infection has a harmful effect on the progression of HCV, resulting in greater rates of HCV persistence after acute infection, higher viral levels, and accelerated progression of liver fibrosis and end-stage liver disease. In this study, we developed and investigated a mathematical model for the dynamical behavior of HIV/AIDS and HCV co-infection, which includes therapy for both diseases, vertical transmission in HIV cases, unawareness and awareness of HIV infection, inefficient HIV treatment follow-up, and efficient condom use. Methods: Positivity and boundedness of the model under investigation were established using well-known theorems. The equilibria were demonstrated by bringing all differential equations to zero. The associative reproduction numbers for mono-infected and dual-infected models were calculated using the next-generation matrix approach. The local and global stabilities of the models were validated using the linearization and comparison theorem and the negative criterion techniques of bendixson and dulac, respectively. Results: The growing prevalence of HIV treatment dropout in each compartment of the HIV model led to a reduction in HIV on treatment compartments while other compartments exhibited an increase in populations . In dually infected patients, treating HCV first reduces co-infection reproduction number R ech , which reduces liver cancer risk. Conclusions: From the model's results, we infer various steps that policymakers could take to reduce the number of mono-infected and co-infected individuals.

Mathematical modeling of HIV-HCV co-infection model: Impact of parameters on reproduction number

Background: Hepatitis C Virus (HCV) and Human Immunodeficiency Virus (HIV) are both classified as blood-borne viruses since they are transmitted through contact with contaminated blood. Approximately 1.3 million of the 2.75 million global HIV/HCV carriers are people who inject drugs (PWID). HIV co-infection has a harmful effect on the progression of HCV, resulting in greater rates of HCV persistence after acute infection, higher viral levels, and accelerated progression of liver fibrosis and end-stage liver disease. In this study, we developed and investigated a mathematical model for the dynamical behavior of HIV/AIDS and HCV co-infection, which includes therapy for both diseases, vertical transmission in HIV cases, unawareness and awareness of HIV infection, inefficient HIV treatment follow-up, and efficient condom use. Methods: Positivity and boundedness of the model under investigation were established using well-known theorems. The equilibria were demonstrated by bringing all differential equations to zero. The associative reproduction numbers for mono-infected and dual-infected models were calculated using the next-generation matrix approach. The local and global stabilities of the models were validated using the linearization and comparison theorem and the negative criterion techniques of bendixson and dulac, respectively. Results: The growing prevalence of HIV treatment dropout in each compartment of the HIV model led to a reduction in HIV on treatment compartments while other compartments exhibited an increase in populations . In dually infected patients, treating HCV first reduces co-infection reproduction number R ech , which reduces liver cancer risk. Conclusions: From the model's results, we infer various steps (such as: campaigns to warn individuals about the consequences of having multiple sexual partners; distributing more condoms to individuals; continuing treatment for chronic HCV and AIDS) that policymakers could take to reduce the number of mono-infected and co-infected individuals.

Elimination of hepatitis C among HIV-positive population in Asia: old and new challenges

Hepatitis C virus (HCV) prevalence is high among people living with HIV co-infected with HCV, people who inject drugs, men who have sex with men and inmates in correctional settings. The barriers to eliminate HCV among these key populations include diagnosis challenges, lack of awareness, discrimination and stigmatization. In addition, scaling up of HCV treatment has been a challenge in Asia–Pacific with the lack of national policies, targets and unavailability of appropriate direct-acting antivirals regimens. In order to achieve HCV micro elimination within these high-risk populations, novel strategies to improve the cascade of care from diagnosis to treatment with direct-acting antivirals, complemented by behavioral change interventions, harm reduction services for people who inject drugs, civil society led advocacy and policies from the government, will be necessary.

Insights Into the Pathophysiology of Liver Disease in HCV/HIV: Does it End With HCV Cure?

HCV-HIV coinfected patients exhibit rapid progression of liver damage relative to HCV monoinfected patients. The availability of new directly acting antiviral agents has dramatically improved outcomes for coinfected patients as sustained virologic response rates now exceed 95% and fibrosis-related parameters are improved. Nevertheless, coinfected patients still have a higher mortality risk and more severe hepatocellular carcinoma compared to HCV monoinfected patients, implying the existence of pathways unique to people living with HIV that continue to promote accelerated liver disease. In this article, we review the pathobiology of liver disease in HCV-HIV coinfected patients in the directly acting antiviral era and explore the mechanisms through which HIV itself induces liver damage. Since liver disease is one of the leading causes of non-AIDS-related mortality in HIV-positive patients, enhancing our understanding of HIV-associated fibrotic pathways will remain important for new diagnostic and therapeutic strategies to slow or reverse liver disease progression, even after HCV cure.

Hepatitis C Care Continuum in a Human Immunodeficiency Virus (HIV) Positive Cohort: Data From the HIV Atlanta Veterans Affairs Cohort Study

Background

Human immunodeficiency virus (HIV) and hepatitis C virus (HCV) coinfection is associated with accelerated progression to cirrhosis, end-stage liver disease, and liver-associated death. It is fortunate that curative direct-acting antivirals for the treatment of HCV are widely available in the VA healthcare system. We attempted to identify, evaluate, and treat all HIV/HCV-coinfected persons at the Atlanta VA Healthcare System.

Methods

Human immunodeficiency virus/HCV-coinfected persons at Atlanta VA between 2015 and 2018 were identified using the HIV Atlanta Veterans Affairs Cohort Study and Hepatitis C VA Clinical Case Registry. Retrospective reviews of each electronic medical record were conducted by the hepatitis C clinical team for validation. The primary end point was achieving sustained virologic response.

Results

One hundred thirty-eight veterans with HIV and hepatitis C viremia were identified. One hundred twenty-five (90%) were evaluated for treatment and 113 (91%) were initiated on direct-acting antiviral therapy. Median age at initiation of treatment was 60 years and the majority were black race (90%). Genotype 1a was most common (70%) and 41% had compensated cirrhosis. One hundred eight completed treatment and 96% achieved sustained virologic response. Six veterans had virologic relapse; 4 had treatment-emergent resistance mutations in the NS5a gene. Mean CD4 was 580 cells/mm³ with HIV viral suppression in 82% of the cohort. In those not treated, unstable housing (25%), active substance use (31%), and psychiatric conditions (42%) were identified barriers to care.

Conclusions

Through a concerted, systematic effort, over 80% of HIV/hepatitis C persons in the Atlanta VA have been initiated on treatment for hepatitis C, 96% of which have been cured.

Molecular characterization of carboxypeptidase B-like (CPB) in Scylla paramamosain and its role in white spot syndrome virus and Vibrio alginolyticus infection

Carboxypeptidase plays an important physiological role in the tissues and organs of animals. In this study, we cloned an entire 2316 bp carboxypeptidase B-like (CPB) sequence with a 1302 bp open reading frame encoding a 434 amino acid peptide from Scylla paramamosain. The CPB gene was expressed highly in hepatopancreas and decreased in crab hemocytes after challenges with white spot syndrome virus (WSSV) or Vibrio alginolyticus. After CPB gene knockdown using double-stranded RNA (CPB-dsRNA), the expression of JAK, STAT, C-type lectin, crustin antimicrobial peptide, Toll-like receptors, prophenoloxidase, and myosin II essential light chain-like protein were down-regulated in hemocytes at 24 h post dsRNA treatment. CPB knockdown decreases total hemocyte count in crabs indicated that CPB may negatively regulate crab hemocyte proliferation in crabs. CPB showed an inhibitory effect on hemocyte apoptosis in crabs infected with WSSV or V. alginolyticus. The phagocytosis rate of WSSV by hemocytes was increased after CPB-dsRNA treatment. After WSSV challenge, the mortality and WSSV copy number were both decreased but the rate of hemocyte apoptosis was increased in CPB-dsRNA-treated crabs. The results indicate that the antiviral activity of the crabs was enhanced when CPB was knocked down, indicating WSSV may take advantage of CPB to benefit its replication. In contrast, the absence of CPB in crabs increased mortality following the V. alginolyticus challenge. The phagocytosis rate of V. alginolyticus by hemocytes was increased after CPB-dsRNA treatment. It was revealed that CPB may play a positive role in the immune response to V. alginolyticus through increasing the phagocytosis rate of V. alginolyticus. This research further adds to our understanding of the CPB and identifies its potential role in the innate immunity of crabs.

Retrospective study of hepatitis C outcomes and treatment in HIV co-infected persons from the Australian HIV Observational Database

BACKGROUND

The widespread availability of direct-acting antivirals (DAAs) is expected to drastically improve the treatment uptake and cure rate of hepatitis C virus (HCV). In this paper, rates of and factors associated with HCV treatment uptake and cure in the HIV co-infected population in Australia were assessed before access to DAAs.

METHODS

The medical records of patients in the Australian HIV Observational Database who were reported to be HCV antibody positive from 1999 to 2014 were reviewed for HCV treatment data. Patients with detectable HCV RNA were included in this analysis. Logistic regression models were applied to identify factors associated with treatment uptake and HCV sustained virological response (SVR) 24 weeks' post treatment.

RESULTS

The median follow-up time of those with chronic HCV/HIV co-infection was 103 months (interquartile range 51-166 months). Of 179 HCV viraemic patients, 79 (44.1%) began treatment. In the adjusted model, a higher METAVIR score was the only significant factor associated with treatment uptake (odds ratio (OR) 8.87, 95% confidence interval (CI) 2.00-39.3, P=0.004). SVR was achieved in 37 (50%) of 74 treated patients. HCV genotypes 2/3 compared with 1/4 remained the only significant factor for SVR in an adjusted multivariable setting (OR 5.44, 95% CI 1.53-19.4, P=0.009).

CONCLUSIONS

HCV treatment uptake and SVR have been relatively low in the era of interferon-containing regimens, in Australian HIV/HCV coinfected patients. With new and better tolerated DAAs, treatment of HCV is likely to become more accessible, and identification and treatment of HCV in co-infected patients should become a priority.

CD4/CD8 ratio predicts the cellular immune response to acute hepatitis C in HIV-coinfected adults

Hepatitis C virus (HCV) coinfection is a strong risk factor for death of HIV-infected patients. Immune dysfunction affects the clinical course of acute hepatitis C (AHC). CD4/CD8 ratio is a biomarker of both persistent inflammation and immunosenescence in HIV-infected adults on effective antiretroviral therapy. A low CD4/CD8 ratio predicts immunosenescence and is associated with increased morbidity and mortality in both HIV-infected adults and elderly HIV-uninfected adults. Additionally, immunosenescence is associated with unresponsiveness to vaccine and could affect the immune reaction to pathogens during their primary infection. We retrospectively evaluated 12 AHC patients to assess the association between CD4/CD8 ratio and liver damage in AHC. We used the Spearman rank correlation test to assess the correlation. We found that CD4/CD8 ratio and peak alanine aminotransferase level (peak ALT) were positively correlated (r = 0.8322, p = 0.0013). The CD4 counts did not correlate with peak ALT (r = 0.5245, p = 0.0839). CD8⁺ T cells expansion for AHC did not affect these results, because the CD4/CD8 ratio before the onset of AHC and peak ALT positively correlate (n = 11; r = 0.7909, p = 0.0055) and there was no significant difference between CD4/CD8 ratios before and after the onset of AHC (n = 11; p = 0.9766). Immunosenescence may be negatively associated with the cellular immune response to acute HCV infection. We suggest that clinicians consider using CD4/CD8 ratio as a marker of immunosenescence in their management of patients with HIV infection and other complications.

Liver stiffness regression after successful Hepatitis C treatment is independent of HIV coinfection

OBJECTIVES

The aim of the study was to assess the regression of liver stiffness after successful direct-acting antiviral (DAA) treatment in patients with hepatitis C virus (HCV) monoinfection and HCV/-HIV coinfection. In addition, we aimed to identify factors associated with liver stiffness regression.

METHODS

We studied patients treated with interferon-free DAA regimens with a sustained virological response at week 12 (SVR₁₂ ) or 24 (SVR₂₄ ) post-treatment. Liver stiffness was assessed by transient elastography (TE) before the initiation and after the end of treatment (median 12 weeks).

RESULTS

Of 214 enrolled patients, 85 (40%) were HCV monoinfected and 129 (60%) HCV/HIV coinfected. Baseline median TE values were 7.8 kPa [interquartile range (IQR) 5.9-12.0 kPa] in mono-infected patients and 10.7 kPa (IQR 7.8-17.0 kPa) in coinfected patients. Overall, the median TE value decreased from 10.1 to 6.8 kPa (n = 214; P < 0.0001). There was no difference between mono- and coinfected patients (-2.2 versus -3.3 kPa, respectively; P = 0.88), which was verified by an analysis of covariance (ANCOVA) adjusting for baseline TE values. Significant (≥ 30%) regression of liver stiffness was achieved by 45% of patients (54% with baseline TE ≥ 7.1 kPa). In multivariate analysis, a prior HCV treatment was a negative predictor of liver stiffness regression [odds ratio (OR) 0.31; P = 0.001]. A higher baseline TE value was positively associated with achieving a significant regression (OR 1.06; P = 0.02). HIV coinfection status, HCV genotype, age, sex, treatment duration, controlled attenuation parameter value, bilirubin concentration, platelet count and aspartate aminotransferase concentration were not associated with liver stiffness regression.

CONCLUSIONS

Regression of liver stiffness after successful DAA treatment did not differ in patients with HCV monoinfection and those with HCV/HIV coinfection. Half of all patients achieved a significant (≥ 30%) regression. Prior treatment for HCV was a negative predictor for this endpoint, while a higher baseline TE value was positively associated with regression.

Shrimp miR-1000 Functions in Antiviral Immunity by Simultaneously Triggering the Degradation of Two Viral mRNAs

MicroRNAs (miRNAs) function as crucial suppressors of gene expression via translational repression or direct mRNA degradation. However, the mechanism of multi-gene regulation by a host miRNA in antiviral immunity has not been extensively explored. In this study, the regulation of two white spot syndrome virus (WSSV) genes by its host (Marsupenaeus japonicus shrimp) miRNA (shrimp miR-1000) was characterized. The miRNA target gene prediction showed that only two virus genes (wsv191 and wsv407) might be the targets of miR-1000. The results of insect cell transfection assays revealed that shrimp miR-1000 could target multiple virus genes (wsv191 and wsv407). The mRNA degradation analysis and RNA FISH (fluorescence in situ hybridization) analysis indicated that miR-1000 triggered the mRNA degradation of target genes through 5′-3′ exonucleolytic digestion in vivo and thereby inhibited the virus infection in shrimp. The miRNA-mediated 5′-3′ exonucleolytic digestion of target mRNAs stopped near the 3′UTR (3′untranslated region) sequence complementary to the seed sequence of miR-1000. Therefore, our study provided novel insights into how a host miRNA targeted multiple viral genes and prevented host from virus infection.

Direct-Acting Antivirals Improve Access to Care and Cure for Patients With HIV and Chronic HCV Infection

Background

Direct-acting antivirals (DAA) as curative therapy for hepatitis C virus (HCV) infection offer >95% sustained virologic response (SVR), including in patients with human immunodeficiency virus (HIV) infection. Despite improved safety and efficacy of HCV treatment, challenges remain, including drug-drug interactions between DAA and antiretroviral therapy (ART) and restrictions on access by payers.

Methods

We performed a retrospective cohort study of all HIV/HCV co-infected and HCV mono-infected patients captured in care at our institution from 2011-2015, reflecting the DAA era, to determine treatment uptake and SVR, and to elucidate barriers to accessing DAA for co-infected patients.

Results

We identified 9290 patients with HCV mono-infection and 507 with HIV/HCV co-infection. Compared to mono-infected patients, co-infected patients were younger and more likely to be male and African-American. For both groups, treatment uptake improved from the DAA/pegylated interferon (PEGIFN)-ribavirin to IFN-free DAA era. One-third of co-infected patients in the IFN-free DAA era required ART switch and nearly all remained virologically suppressed after 6 months. We observed SVR >95% for most patient subgroups including those with co-infection, prior treatment-experience, and cirrhosis. Predictors of access to DAA for co-infected patients included Caucasian race, CD4 count ≥200 cells/mm³, HIV virologic suppression and cirrhosis. Time to approval of DAA was longest for patients insured by Medicaid, followed by private insurance and Medicare.

Conclusions

DAA therapy has significantly improved access to HCV treatment and high SVR is independent of HIV status. However, in order to realize cure for all, barriers and disparities in access need to be urgently addressed.

Prevalence and predictors of liver disease in HIV-infected children and adolescents

Liver disease in HIV-infected patients may result from the infection itself, antiretroviral treatment or comorbidities. In this study, we analysed liver disease in 79 HIV-infected children and adolescents aged 14.0 ± 5.1 years. All the patients were receiving combination antiretroviral therapy (cART), with a mean duration of 11.5 ± 4.7 years. Six patients (8%) had detectable HIV viral load, and 8/79 (10%) of the participants were coinfected with hepatitis B or C virus (HCV, 6/8 or HBV, 2/8). Liver disease was defined as an elevation of any of the following parameters: alanine or aspartate aminotransferase (ALT and AST), total bilirubin, and gamma glutamyl transferase (GGTP). For the noninvasive evaluation of liver fibrosis, the AST-to-Platelet Ratio Index (APRI) and Fibrosis-4 (FIB-4) were calculated. Liver disease was diagnosed in 20/79 (25%) of the patients, including 13/71 (18%) of participants without coinfection and 7/8 (88%) with coinfection (p < 0.0001). All of the liver markers except bilirubin were significantly higher in the coinfected group. APRI scores indicated significant fibrosis in 5/8 (63%) of patients with coinfection. HBV or HCV coinfection and detectable HIV viral load were independently positively associated with APRI (p = 0.0001, and p = 0.0001) and FIB-4 (p = 0.001, and p = 0.002, respectively). In conclusion, liver disease in HIV-infected children and adolescents results mainly from HBV or HCV coinfection. Effective antiretroviral treatment is protective against hepatic abnormalities.

Cell-Mediated Immune Predictors of Vaccine Effect on Viral Load and CD4 Count in a Phase 2 Therapeutic HIV-1 Vaccine Clinical Trial

Background

In a placebo-controlled trial of the peptide-based therapeutic HIV-1 p24^Gag vaccine candidate Vacc-4x, participants on combination antiretroviral therapy (cART) received six immunizations over 18 weeks, followed by analytical treatment interruption (ATI) between weeks 28 and 52. Cell-mediated immune responses were investigated as predictors of Vacc-4x effect (VE) on viral load (VL) and CD4 count during ATI.

Methods

All analyses of week 28 responses and fold-changes relative to baseline considered per-protocol participants (Vacc-4x:placebo = 72:32) resuming cART after week 40. Linear regression models with interaction tests were used. VE was estimated as the Vacc-4x–placebo difference in log₁₀-transformed VL (VE^VL) or CD4 count (VE^CD4).

Findings

A lower fold-change of CD4+ T-cell proliferation was associated with VE^CD4 at week 48 (p = 0.036, multiplicity adjusted q = 0.036) and week 52 (p = 0.040, q = 0.080). A higher fold-change of IFN-γ in proliferation supernatants was associated with VE^VL at week 44 (p = 0.047, q = 0.07). A higher fold-change of TNF-α was associated with VE^VL at week 44 (p = 0.045, q = 0.070), week 48 (p = 0.028, q = 0.070), and week 52 (p = 0.037, q = 0.074). A higher fold-change of IL-6 was associated with VE^VL at week 48 (p = 0.017, q = 0.036). TNF-α levels (> median) were associated with VE^CD4 at week 48 (p = 0.009, q = 0.009).

Interpretation

These exploratory analyses highlight the potential value of investigating biomarkers in T-cell proliferation supernatants for VE in clinical studies.

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Ex vivo CD4+ T-cell proliferation was predictive of Vacc-4x effect.

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IFN-γ, TNF-α and IL-6 secretion in T-cell proliferation supernatants were predictive of Vacc-4x effect.

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Such immune predictors could be utilized to mitigate risks associated with cART interruption towards HIV cure.

No immune correlates or predictors of therapeutic vaccine effect (i.e. a reduction in viral load compared to placebo on treatment interruption) for human immunodeficiency virus (HIV)-1 are known. We investigated a broad array of cytokines/chemokines produced in T-cell proliferation supernatants from a placebo-controlled clinical study of a therapeutic HIV vaccine. Although such supernatants do not provide cell type-specific readouts, the cytokines/chemokines studied included T-helper (Th)1, Th2, growth factor, immuno-modulatory and pro-inflammatory functions. Specifically, we found that, IFN-γ, TNF-α and IL-6 secretion correlated with vaccine effect, suggesting such supernatants could represent important sample material not previously considered for the identification of immune markers of vaccine effect.

Comparison of HCV viral load and its genotype distributions in HCV mono- and HIV/HCV co-infected illicit drug users

BACKGROUND

Because of shared modes of transmission, patients with hepatitis C virus (HCV) infection are often co-infected with other types of hepatitis viruses and/or HIV. We studied HCV viral load and its genotype patterns among HCV mono- and HCV/HIV co-infected Illicit Drug Users in Fars province-Iran.

METHODS

Totally, 580 HCV seropositive IDUs referred to Prof. Alborzi Clinical Microbiology Research Center, Shiraz, Iran, without receiving any anti-HCV treatment, were enrolled. After their HCV infections were reconfirmed by one step rapid diagnostic test, HCV RNA level and HCV genotypes were determined by Taq-man real-time PCR assays. Their HIV serostatus was determined and seropositive patients were excluded from the group. In addition, 104 HIV/HCV co-infected IDUs referred from Shiraz Behavioral Diseases Consultation Center (SBDC) were assessed for HCV RNA level and HCV genotype patterns, as well.

RESULTS

The overall estimated HIV prevalence was 6.7% (39/580) among HCV seropositive IDUs. Genotype 1, the most prevalent genotype in both groups, was detected in 69% and 49% of co- and mono-infected IDUs, respectively. Median HCV viral load was significantly higher in HIV/HCV co-infected patients, compared with that among HCV mono-infected counterparts.

CONCLUSIONS

Given the higher baseline HCV viral load and GT1 attributed to poorer treatments response, HCV treatment must be more considered among HCV/HIV co-infected IDUs, compared to those mono-infected with HCV.

Prevalence of hepatitis C virus infection among HIV+ men who have sex with men: a systematic review and meta-analysis

Since 2000, an increase in hepatitis C virus infection among HIV-infected (HIV+) men who have sex with men has been observed. Evidence points to blood exposure during sex as the medium of hepatitis C virus transmission. Hepatitis C virus prevalence among HIV + MSM overall and in relation to injection drug use is poorly characterized. In this study, a systematic review and meta-analysis examining global hepatitis C virus antibody prevalence and estimating active hepatitis C virus prevalence among HIV + MSM were conducted; 42 reports provided anti-hepatitis C virus prevalence data among HIV + MSM. Pooled prevalence produced an overall anti-hepatitis C virus prevalence among HIV + MSM of 8.1%; active HCV prevalence estimate was 5.3%-7.3%. Anti-hepatitis C virus prevalence among injection drug use and non-injection drug use HIV + MSM was 40.0% and 6.7%, respectively. Among HIV + MSM, hepatitis C virus prevalence increased significantly over time among the overall and non-injection drug use groups, and decreased significantly among injection drug use HIV + MSM. We identified a moderate prevalence of hepatitis C virus among all HIV + MSM and among non-injection drug use HIV + MSM; for both, prevalence was observed to be increasing slightly. Pooled prevalence of hepatitis C virus among HIV + MSM was higher than that observed in the 1945-1965 US birth cohort. The modest but rising hepatitis C virus prevalence among HIV + MSM suggests an opportunity to control HCV among HIV + MSM; this combined with data demonstrating a rising hepatitis C virus incidence highlights the temporal urgency to do so.

Coinfection with HIV and hepatitis C virus in 229 children and young adults living in Europe

OBJECTIVE

To characterize children, adolescents and young adults infected with HIV/hepatitis C virus (HCV) vertically or before age of 18 years and living in Europe regarding mode of acquisition, HCV genotype, clinical status and treatment.

DESIGN

Retrospective, cross-sectional study using pooled data from 11 European paediatric HIV cohorts.

METHODS

Patients aged more than 18 months and less than 25 years, with HIV/HCV acquired vertically or in childhood, were included. Anonymized individual patient data were collected using a standard protocol and modified HIV Cohorts Data Exchange Protocol.

RESULTS

Of 229 patients included, 142 (62%) had vertically acquired infection. Median age at last follow-up was 16.2 years. Most children had HCV genotype 1 (101/184, 55%) or 3 (57/184, 31%). One-fifth (46/214) had a previous AIDS diagnosis (data missing on prior AIDS diagnoses for 15). At their last clinic visit, 70% (145/208) had no/mild immunosuppression (Centers for Disease Control and Prevention stage 1), and 131 of 179 on antiretroviral therapy had undetectable HIV RNA (assay thresholds varied from <20 to <150 copies/ml). Overall, 42% (86/204) had hepatomegaly in the previous year, and 55% (116/213) had alanine aminotransferase more than 40 IU/l at their last test. Of 97 patients with transient elastography, 12 had results more than 9 kPa; this was associated with duration of HCV infection (P = 0.033), but not with CD4 cell count, antiretroviral therapy use or sex in univariable analysis. Of 17 patients with liver biopsies, six had bridging fibrosis and one had cirrhosis. Twenty-five (11%) had been treated successfully for HCV.

CONCLUSION

The high proportion of patients with progressive liver disease underscores the need for close monitoring and earlier and more effective HCV treatment.

Treatment optimization for HIV/HCV co-infected patients

Human immunodeficiency virus (HIV) and hepatitis C virus (HCV) infections affect millions of persons around the globe and cause profound morbidity and mortality. A major intersection exists between these two epidemics, with HCV infection being more common in persons with HIV than in the general population, largely due to shared routes of transmission. HCV co-infection increases risk for liver- and non-liver-related morbidity and mortality, making HCV treatment a priority in HIV co-infected persons, but the treatment of HCV in co-infected patients has been daunting for multiple reasons. Until recently, HCV treatment has frequently been deferred due to the low rates of cure, significant adverse effects, burdensome duration of therapy and drug-drug interactions with HIV antiretroviral medications. Untreated HCV has resulted in significant health consequences for the millions of those infected and has led to multiple downstream impacts on our healthcare systems around the world. The development of a remarkable number of new HCV direct-acting agents (DAAs) that are significantly more efficacious and tolerable than the previous interferon-based regimens has transformed this important field of medicine, with the potential to dramatically reduce the burden of infection and improve health outcomes in this population. This review will summarize the epidemiology and clinical impact of HIV/HCV co-infection and current approaches to the treatment of HCV in HIV/HCV co-infected patients.

Optimum combination therapy regimens for HIV/HCV infection

HIV-HCV co-infection mostly affects intravenous drug users, in whom prevalence has tended to decrease in recent years, while it has increased in men who have sex with men, with occurrence of acute hepatitis C. Hepatitis C has a poorer prognosis in patients co-infected with HIV, as clinical progression is faster and degree of hepatic fibrosis is greater. However, optimized ARV treatment is clearly associated with slower progression to hepatic complications. Interactions between HCV and HIV drugs are numerous, which underlines the importance of pharmacological advice for HIV-treated patients before they start HCV treatment. In HIV-HCV co-infection, treatment of hepatitis C has to be offered as in mono-infected patients (US and European countries) or to all patients (French guidelines). In most patients, HCV eradication is achieved with different DAA associations, the choice and duration being driven by HCV genotype, hepatic fibrosis stage, and whether patients have been previously treated or not.

A Comprehensive Analysis of the Impact of HIV on HCV Immune Responses and Its Association with Liver Disease Progression in a Unique Plasma Donor Cohort

Objective

Human Immunodeficiency Virus (HIV) and Hepatitis C virus (HCV) co-infection is recognized as a major cause of morbidity and mortality among HIV-1 infected patients. Our understanding of the impact of HIV infection on HCV specific immune responses and liver disease outcome is limited by the heterogeneous study populations with genetically diverse infecting viruses, varying duration of infection and anti-viral treatment.

Methods

Viral-specific immune responses in a cohort of 151 HCV mono- and HIV co-infected former plasma donors infected with a narrow source of virus were studied. HCV and HIV specific T cell responses were correlated with clinical data.

Results

HIV-1 accelerated liver disease progression and decreased HCV specific T cell immunity. The magnitude of HCV specific T cell responses inversely correlated with lower HCV RNA load and reduced liver injury as assessed by non-invasive markers of liver fibrosis. HIV co-infection reduced the frequency of HCV specific CD4⁺ T cells with no detectable effect on CD8⁺ T cells or neutralizing antibody levels.

Conclusion

Our study highlights the impact of HIV co-infection on HCV specific CD4+ T cell responses in a unique cohort of patients for both HCV and HIV and suggests a crucial role for these cells in controlling chronic HCV replication and liver disease progression.

Clinical outcomes of patients infected with HIV through use of injected drugs compared to patients infected through sexual transmission: late presentation, delayed anti-retroviral treatment and higher mortality

AIMS

To compare patients who acquired HIV infection through use of injected drugs (HIV-IDU) with patients who acquired HIV by sexual transmission (HIV-ST) in terms of late presentation (LP), delay in anti-retroviral treatment (ART) initiation, virological and immunological response to ART, mortality and progression to AIDS.

DESIGN

Prospective multi-centre cohort study of HIV-infected subjects naive to ART at entry (Cohort of the Spanish HIV Research Network: CoRIS).

SETTING

Thirty-one centres from the Spanish public health-care system.

PARTICIPANTS

A total of 9355 patients were included (1064 HIV-IDU and 8291 HIV-ST) during 2004-13.

MEASUREMENTS

We compared LP (defined as presentation for care with a CD4 cell count < 350/μl and/or AIDS-defining illness), delayed ART initiation (defined as initiating treatment more than 6 months after the date when treatment was indicated by the guidelines, or not initiating treatment at all when it was indicated), virological and immunological response to ART (defined as viral load < 50 HIV-1 RNA copies/ml and a CD4 count increase of at least 100 cells/μl, respectively, after 1 year of treatment), mortality and progression to AIDS in HIV-IDU and HIV-ST.

FINDINGS

Compared with HIV-ST, HIV-IDU had higher risk of LP [odds ratio (OR) = 1.76; 95% confidence interval (CI) = 1.41-2.18], delayed ART initiation (OR 1.87; 95% CI = 1.46-2.40) and higher mortality [hazard ratio (HR) = 1.43; 95% CI = 1.03-2.01] and risk of progression to AIDS [subhazard ratio (SHR) = 1.68; 95% CI = 1.29-2.18]. Virological suppression due to ART was lower in HIV-IDU than in patients with HIV-ST only among patients without hepatitis C virus (HCV) infection [adjusted OR (aOR) = 0.59; 95% CI = 0.36-0.95]; among patients with HCV infection, virological suppression due to ART did not show significant differences between HIV-IDU and HIV-ST. There were no significant differences in immunological response after adjusting by HCV (aOR = 0.74; 95% CI = 0.52-1.06).

CONCLUSIONS

In Spain, patients who acquire HIV infection through use of injected drugs appear to have a higher risk of late presentation, delayed initiation of anti-retroviral treatment and progression to AIDS and death than patients who acquire HIV by sexual transmission.

Key drug-drug interactions with direct-acting antiviral in HIV-HCV coinfection

PURPOSE OF REVIEW

We reviewed the most recent data on pharmacokinetic interactions between hepatitis C direct-acting antiviral (DAA) agents and HIV antiretrovirals (ARVs).

RECENT FINDINGS

Drug interactions between DAAs and HIV ARVs are extrapolated from phase 1 drug-drug interaction (DDI) studies in healthy volunteers. Safety and efficacy data of DAA-ARV combinations are largely limited to the drug combinations permitted in phase 2 and 3 HIV-HCV coinfection trials. Paritapervir/ritonavir with ombitasvir and dasabuvir (3D) should not be coadministered with efavirenz, etravirine, elvitegravir/cobicistat or with additional doses of ritonavir. Atazanavir, darunavir and rilpivirine require cautious monitoring when used with 3D. The combination of sofosbuvir and ledipasvir can be safely used with most ARVs, but there is a risk of hyperbilirubinaemia with atazanavir. Tenofovir exposure is significantly increased when used with sofosbuvir-ledipasvir and a boosted protease inhibitor or emtricitabine/efavirenz, and therefore should be used with cautious monitoring for renal toxicity only when alternative therapy is not possible. Daclatasvir requires dosage modification with atazanavir, efavirenz and cobicistat. The coadministration of simeprevir with efavirenz, etravirine or ritonavir-boosted and cobicistat-boosted regimens is not recommended.

SUMMARY

The safety and efficacy of HCV therapy in HIV-HCV coinfection is now comparable with HCV monoinfection, but drug interactions need to be carefully considered before instituting therapy to minimize potential harm. Real-world data are required to further assess the clinical implications of some DDIs.

Cytokine Response Associated with Hepatitis C Virus Clearance in HIV Coinfected Patients Initiating Peg Interferon-α Based Therapy

Background

Treatment of hepatitis C virus (HCV) infection based on peginterferon-α (pegIFNα) and ribavirin induces important changes in cytokine release and T cell activation.

Objective

Immune response to pegIFNα-ribavirin therapy was explored in patients coinfected by HCV and HIV.

Methods

Concentrations of 25 cytokines and CD8⁺ T cell activation were monitored in HCV/HIV coinfected patients classified as sustained virological responders (SVR, n=19) and non-responders (NR, n=11).

Results

High pretreatment concentrations of IP-10 (CXCL-10) and MCP-1 (CCL-2) were associated with a poor anti-HCV response. PegIFNα-ribavirin therapy increased CD8⁺ T cell activation and induced significant changes in levels of eleven cytokines related to both Th1 and Th2 responses in SVR (IL-1β, IL-1RA, IL-4, IL-5, IL-6, IL-7, IL-12p40/70, IL-13, IP-10, eotaxin, MCP-1) but of only six cytokines in NR (IL-1β, IL-2, IL-5, IL-12p40/70, IL-13, eotaxin). The highest rise in MIP-1β and MCP-1 levels was observed four weeks after anti-HCV treatment initiation in SVR compared to NR (p=0.002 and p=0.03, respectively), whereas a decrease in IL-8 concentration was associated with treatment failure (p= 0.052).

Conclusions

Higher and broader cytokine responses to pegIFNα-ribavirin therapy were observed in SVR patients compared to NR. Changes in IL-8, MIP-1β, and MCP-1 serum concentrations may be associated with efficacy of pegIFNα- and ribavirin-based therapies in patients coinfected by HCV and HIV.

Hepatitis C genotype 4: The past, present, and future

Hepatitis C virus (HCV) genotype (GT) 4 represents 12%-15% (15-18 million) of total global HCV infection. It is prevalent in Northern and Equatorial Africa and the Middle East, and is also present in some countries in Europe. GT-4 (and subtype 4a in particular) dominates the HCV epidemic in Egypt. In underdeveloped countries, risk factors associated with HCV infection may be due to unsafe medical practices or other factors such as familial transmission, mother’s HCV status, or illiteracy. HCV prevention and control programs should include health education, increased community awareness towards the disease, controlling infection distribution in health-care centers, proper sterilization of medical and dental instruments, and ensuring safe supply of blood and blood-products. Response rates to a 48-wk combined pegylated-interferon (PEG-IFN) and ribavirin (RBV) treatment range from 40%-69%, and HCV-GT-4 has been considered better than GT-1 but worse than GT-2 and GT-3 in treatment with PEG-IFN/RBV. However, with the introduction of the HCV-GT-1 effective protease inhibitors boceprevir and telaprevir in 2011, HCV-GT-4 became the “most difficult (GT) to treat”. Recently, the direct-acting antivirals (DAAs) with pan- genotypic activities simeprevir, sofosbuvir, and daclatasvir have been recommended in triple regimens with PEG-IFN/RBV for the treatment of HCV-GT-4. An IFN-free regimen will be available for treatment of all genotypes of HCV in the near future. To date, several DAAs have been developed and are currently being evaluated in various combinations in clinical trials. As new regimens and new agents are being approved by the Food and Drug Administration, we can expect the guidelines for HCV treatment to be changed. The availability of shorter, simpler, and more tolerable treatment regimens can reduce the morbidity and mortality associated with HCV infection. With such a large number of therapeutic agents available, we can end up with a range of choices that we can select from to treat patients.

Multiple Introduction and Naturally Occuring Drug Resistance of HCV among HIV-Infected Intravenous Drug Users in Yunnan: An Origin of China's HIV/HCV Epidemics

Background

The human immunodeficiency virus 1 (HIV-1) epidemic in China historically stemmed from intravenous drug users (IDUs) in Yunnan. Due to a shared transmission route, hepatitis C virus (HCV)/HIV-1 co-infection is common. Here, we investigated HCV genetic characteristics and baseline drug resistance among HIV-infected IDUs in Yunnan.

Methods

Blood samples of 432 HIV-1/HCV co-infected IDUs were collected from January to June 2014 in six prefectures of Yunnan Province. Partial E1E2 and NS5B genes were sequenced. Phylogenetic, evolutionary and genotypic drug resistance analyses were performed.

Results

Among the 293 specimens successfully genotyped, seven subtypes were identified, including subtypes 3b (37.9%, 111/293), 3a (21.8%, 64/293), 6n (14.0%, 41/293), 1b (10.6%, 31/293), 1a (8.2%, 24/293), 6a (5.1%, 15/293) and 6u (2.4%, 7/293). The distribution of HCV subtypes was mostly related to geographic location. Subtypes 3b, 3a, and 6n were detected in all six prefectures, however, the other four subtypes were detected only in parts of the six prefectures. Phylogeographic analyses indicated that 6n, 1a and 6u originated in the western prefecture (Dehong) and spread eastward and showed genetic relatedness with those detected in Burmese. However, 6a originated in the southeast prefectures (Honghe and Wenshan) bordering Vietnam and was transmitted westward. These subtypes exhibited different evolutionary rates (between 4.35×10⁻⁴ and 2.38×10⁻³ substitutions site^-1 year^-1) and times of most recent common ancestor (tMRCA, between 1790.3 and 1994.6), suggesting that HCV was multiply introduced into Yunnan. Naturally occurring resistance-associated mutations (C316N, A421V, C445F, I482L, V494A, and V499A) to NS5B polymerase inhibitors were detected in direct-acting antivirals (DAAs)-naïve IDUs.

Conclusion

This work reveals the temporal-spatial distribution of HCV subtypes and baseline HCV drug resistance among HIV-infected IDUs in Yunnan. The findings enhance our understanding of the characteristics and evolution of HCV in IDUs and are valuable for developing HCV prevention and management strategies for this population.

National Trend and Characteristics of Acute Hepatitis C among HIV-Infected Individuals: A Matched Case-Control Study-Taiwan, 2001-2014

Background

Hepatitis C virus (HCV) infection has been increasingly recognized among HIV-infected men who have sex with men (MSM) worldwide. We investigated the trend of and factors associated with acute hepatitis C (AHC) among HIV-infected individuals in Taiwan.

Methods

The National Disease Surveillance System collects characteristics of AHC, HIV, syphilis, and gonorrhea cases through mandatory reports and patient interviews. Reported AHC patients in 2014 were interviewed additionally on sexual and parenteral exposures. Information on HCV genotypes were collected from the largest medical center serving HIV-infected Taiwanese. We defined an HIV/AHC case as a documented negative HCV antibody test result followed within 12 months by a positive test in a previously reported HIV-infected individual. Each case was matched to two HIV-infected, non-AHC controls for age, age of HIV diagnosis, sex, transmission route, HIV diagnosis date, and county/city. Conditional logistic regression was used to identify associated characteristics.

Results

During 2001–2014, 93 of 6,624 AHC reports were HIV/AHC cases; the annual case count increased from one in 2009 to 34 in 2014. All were males (81 [87%] MSM) aged 21–49 years with AHC diagnosed 2–5,923 days after HIV diagnoses. Sixty-eight (73%) lived in the Taipei metropolitan area. Detected HCV genotypes were 2a (n = 6), 1b (n = 5), 1b + 2a (n = 1) and 2b (n = 1). Among 28 HIV/AHC patients interviewed in 2014, 13 (46%) reported engaging in unprotected sex ≤3 months before AHC diagnosis. Seventy-nine HIV/AHC cases were matched to 158 controls. HIV/AHC was associated with recent syphilis (adjusted odds ratio [aOR], 10.9; 95% confidence interval [CI], 4.2–28.6) and last syphilis >6 months (aOR, 2.9; 95% CI, 1.2–6.9).

Conclusions

HIV/AHC cases continued to increase particularly among sexually active HIV-infected MSM with a syphilis diagnosis in northern Taiwan. We recommend surveillance of associated behavioral and virologic characteristics and HCV counseling and testing for HIV-infected men in Taiwan.

Hepatitis C in human immunodeficiency virus co-infected individuals: Is this still a "special population"?

A substantial proportion of individuals with chronic hepatitis C virus (HCV) are co-infected with human immunodeficiency virus (HIV). Co-infected individuals are traditionally considered as one of the "special populations" amongst those with chronic HCV, mainly because of faster progression to end-stage liver disease and suboptimal responses to treatment with pegylated interferon alpha and ribavirin, the benefits of which are often outweighed by toxicity. The advent of the newer direct acting antivirals (DAAs) has given hope that the majority of co-infected individuals can clear HCV. However the "special population" designation may prove an obstacle for those with co-infection to gain access to the new agents, in terms of requirement for separate pre-licensing clinical trials and extensive drug-drug interaction studies. We review the global epidemiology, natural history and pathogenesis of chronic hepatitis C in HIV co-infection. The accelerated course of chronic hepatitis C in HIV co-infection is not adequately offset by successful combination antiretroviral therapy. We also review the treatment trials of chronic hepatitis C in HIV co-infected individuals with DAAs and compare them to trials in the HCV mono-infected. There is convincing evidence that HIV co-infection no longer diminishes the response to treatment against HCV in the new era of DAA-based therapy. The management of HCV co-infection should therefore become a priority in the care of HIV infected individuals, along with public health efforts to prevent new HCV infections, focusing particularly on specific patient groups at risk, such as men who have sex with men and injecting drug users.

Spontaneous Clearance of the Hepatitis C Virus Among Men Who Have Sex With Men

BACKGROUND

The probability of spontaneous hepatitis C virus (HCV) clearance ranges from 11% to 49%. Our previous cross-sectional study suggests that mode of acquisition explains some of this heterogeneity. We performed this prospective study to determine factors associated with spontaneous HCV clearance among men who have sex with men (MSM).

METHODS

A mixture-cure model was used to evaluate the probability of spontaneous HCV clearance among 101 MSM in the Multicenter AIDS Cohort Study with acute HCV infection between 1984 and 2012.

RESULTS

Spontaneous HCV clearance occurred in 46% of MSM (49% in non-injection drug users [IDUs] and 23% in IDUs). In the multivariable analysis, age <30 years (clearance ratio [CR] = 2.43; 95% confidence interval [CI], 1.53-3.87) and being human immunodeficiency virus (HIV) uninfected (CR = 2.97; 95% CI, 1.98-4.46) were independently associated with spontaneous clearance. Among men aged ≥30 years, being HIV uninfected, not having unprotected anal intercourse, older age, and being on highly active antiretroviral therapy were independently associated with higher clearance. The interferon lambda rs12979860 single nucleotide polymorphism (SNP) was not associated with spontaneous clearance among the 88 MSM who were not active IDUs (CR = 0.74; 95% CI, .46-1.21 for CC vs CT/TT genotype).

CONCLUSIONS

The high probability of spontaneous HCV clearance together with the lack of an association between the rs12979860 SNP and spontaneous clearance among MSM who do not use injection drugs suggests that the immune mechanisms involved with a successful response to acute HCV differ by mode of virus acquisition. Understanding potential mechanistic differences could be important for HCV vaccine development.

EFFECTS OF TREATMENT, AWARENESS AND CONDOM USE IN A COINFECTION MODEL FOR HIV AND HCV IN MSM

We develop a new a coinfection model for hepatitis C virus (HCV) and the human immunodeficiency virus (HIV). We consider treatment for both diseases, screening, unawareness and awareness of HIV infection, and the use of condoms. We study the local stability of the disease-free equilibria for the full model and for the two submodels (HCV only and HIV only submodels). We sketch bifurcation diagrams for different parameters, such as the probabilities that a contact will result in a HIV or an HCV infection. We present numerical simulations of the full model where the HIV, HCV and double endemic equilibria can be observed. We also show numerically the qualitative changes of the dynamical behavior of the full model for variation of relevant parameters. We extrapolate the results from the model for actual measures that could be implemented in order to reduce the number of infected individuals.

Modeling the effect of HIV coinfection on clearance and sustained virologic response during treatment for hepatitis C virus

BACKGROUND

HIV/hepatitis C (HCV) coinfection is a major concern in global health today. Each pathogen can exacerbate the effects of the other and affect treatment outcomes. Understanding the within-host dynamics of these coinfecting pathogens is crucial, particularly in light of new, direct-acting antiviral agents (DAAs) for HCV treatment that are becoming available.

METHODS AND FINDINGS

In this study, we construct a within-host mathematical model of HCV/HIV coinfection by adapting a previously published model of HCV monoinfection to include an immune system component in infection clearance. We explore the effect of HIV-coinfection on spontaneous HCV clearance and sustained virologic response (SVR) by building in decreased immune function with increased HIV viral load. Treatment is modeled by modifying HCV burst-size, and we use clinically-relevant parameter estimates. Our model replicates real-world patient outcomes; it outputs infected and uninfected target cell counts, and HCV viral load for varying treatment and coinfection scenarios. Increased HIV viral load and reduced CD4(+) count correlate with decreased spontaneous clearance and SVR chances. Treatment efficacy/duration combinations resulting in SVR are calculated for HIV-positive and negative patients, and crucially, we replicate the new findings that highly efficacious DAAs reduce treatment differences between HIV-positive and negative patients. However, we also find that if drug efficacy decays sufficiently over treatment course, SVR differences between HIV-positive and negative patients reappear.

CONCLUSIONS

Our model shows theoretical evidence of the differing outcomes of HCV infection in cases where the immune system is compromised by HIV. Understanding what controls these outcomes is especially important with the advent of efficacious but often prohibitively expensive DAAs. Using a model to predict patient response can lend insight into optimal treatment design, both in helping to identify patients who might respond well to treatment and in helping to identify treatment pathways and pitfalls.

Differences in hepatitis C virus prevalence and clearance by mode of acquisition among men who have sex with men

We examined the characteristics associated with hepatitis C virus (HCV) antibody (anti-HCV) prevalence and HCV clearance between injection drug using (IDU) and non-IDU men who have sex with men (MSM). Stored serum and plasma samples were tested for anti-HCV and HCV RNA to determine the HCV status of 6925 MSM at enrolment into the Multicentre AIDS Cohort Study (MACS). Prevalence and clearance ratios were calculated to determine the characteristics associated with HCV prevalence and clearance. Multivariable analyses were performed using Poisson regression methods with robust variance estimation. Anti-HCV prevalence was significantly higher among IDU than among non-IDU MSM (42.9% vs 4.0%), while clearance was significantly lower among IDU MSM (11.5% vs 34.5% among non-IDU MSM). HIV infection, Black race, and older age were independently associated with higher prevalence in both groups, while smoking, transfusion history, and syphilis were significantly associated with prevalence only among non-IDU MSM. The rs12979860-C/C genotype was the only characteristic independently associated with HCV clearance in both groups, but the effects of both rs12979860-C/C genotype [clearance ratio (CR) = 4.16 IDUs vs 1.71 non-IDUs; P = 0.03] and HBsAg positivity (CR = 5.06 IDUs vs 1.62 non-IDUs; P = 0.03) were significantly larger among IDU MSM. HIV infection was independently associated with lower HCV clearance only among non-IDU MSM (CR = 0.59, 95% CI = 0.40-0.87). IDU MSM have higher anti-HCV prevalence and lower HCV clearance than non-IDU MSM. Differences in the factors associated with HCV clearance suggest that the mechanisms driving the response to HCV may differ according to the mode of acquisition.

Drug interactions between antiretrovirals and new or emerging direct-acting antivirals in HIV/hepatitis C virus coinfection

PURPOSE OF REVIEW

We reviewed the pharmacokinetic interactions between direct-acting antivirals against hepatitis C virus (HCV) and antiretroviral agents.

RECENT FINDINGS

Most relevant pharmacokinetic studies involve healthy individuals and refer to the already licensed HCV protease inhibitors, boceprevir and telaprevir. Data from a phase II clinical trial question the clinical relevance of the interactions between boceprevir and HIV protease inhibitors. The use of a higher dose of telaprevir appears to offset the effect of efavirenz on telaprevir metabolism according to another phase II trial. Boceprevir and particularly telaprevir substantially increase the exposure to maraviroc, similarly to other potent CYP3A4 inhibitors. Different dosages of faldaprevir and daclatasvir have been recommended to be used in combination with a boosted HIV protease inhibitor vs. an efavirenz-based antiretroviral regimen. HIV protease inhibitors appear to substantially increase the exposure to simeprevir. The interactions between sofosbuvir and most antiretroviral agents do not appear to be of clinical relevance or to require dosage modifications.

SUMMARY

The drug-drug interaction studies for HCV direct-acting antivirals and antiretrovirals are important in determining the appropriate drug combinations and dosages. The clinical implications of these interactions need further assessment in different categories of patients, including those with cirrhosis.

Multiple hepatitis C virus (HCV) reinfections in HIV-positive men who have sex with men: no influence of HCV genotype switch or interleukin-28B genotype on spontaneous clearance

OBJECTIVES

The incidence of sexually transmitted hepatitis C virus (HCV) reinfection is on the rise in HIV-infected men who have sex with men (MSM). Data on natural history of acute hepatitis C and possible factors associated with spontaneous clearance are limited. The aim of this study was to analyse the outcome of HCV reinfections in HIV-positive MSM.

METHODS

A retrospective analysis was carried out on patients with more than one sexually acquired HCV infection who were diagnosed at four major German HIV and hepatitis care centres. Reinfection was defined by genotype or phylogenetic clade switch, detectable HCV RNA after a sustained virological response (SVR) or after spontaneous clearance (SC).

RESULTS

In total, 48 HIV-positive MSM were identified with HCV reinfection, among them 11 with a third episode and one patient with four episodes. At the first episode, 43 and five patients had an SVR and SC, respectively. The second episode was accompanied by a genotype switch in 29 patients (60%). Whereas 30 and nine patients showed an SVR and SC, respectively, eight patients developed chronic hepatitis. Neither HCV genotype switch nor interleukin-28B genotype was associated with SC. However, SC rates at the second episode were higher for patients with SC at the first episode compared with patients without SC (60 vs. 14%, respectively; P = 0.03). Two patients with SC at the first episode were reinfected with the same genotype.

CONCLUSIONS

Multiple reinfections in HIV-infected MSM do occur, with or without genotype switch, and with prior SC of previous episodes. In this large case series, except for SC at the first episode, no factor was of value in clinical decision-making for early therapeutic intervention in acute HCV reinfection.

HCV core antigen and HCV-RNA in HIV/HCV co-infected patients with different HCV genotypes

Background

A good correlation between HCV core antigen (HCVAg) and different HCV-RNA assays has been described, but little data are available in HCV/HIV co-infection. We aimed to evaluate HCVAg in comparison with HCV-RNA and to determine their kinetics during antiviral treatment in selected HCV/HIV co-infected patients.

Methods

355 samples from 286 HCV/HIV co-infected subjects for whom HCV-RNA (Abbott RealTime) was requested were analysed also for HCVAg (Abbott ARCHITECT) in order to evaluate the correlation between the two parameters both in patients treated or untreated for chronic hepatitis C and according to different HCV genotypes. The differences between percentages were evaluated by chi square or Fisher’s exact test, while mean and median values were compared by Student’s t test or the Mann–Whitney test, respectively. All differences were considered significant for a p value <0.05.

Results

HCVAg was detectable on 288/315 sera (91.4%) positive for HCV-RNA and in 5 out of40 (12.5%) sera with undetectable HCV-RNA for a total concordance of 90.1%. The correlation was fair both in untreated (r = 0.742) and in treated (r = 0.881) patients and stronger for genotypes 1 and 4 than for genotype 3. Both HCV-RNA and HCVAg levels were significantly higher (p = 0.028 and p = 0.0098, respectively) in patients infected by genotype 1 than by genotype 3. The mean ratio of Log values between HCV-RNA (IU/mL) and HCVAg (fmol/liter) was 2.27 ± 1.09 in untreated and 2.20 ± 0.82 in treated patients (p = n.s.),consistent with a sensitivity of HCVAg corresponding to about 1,000 IU/mL of HCV-RNA, and ranged from 2.21 to 2.32 among HCV genotypes with no significant differences; five samples (1.4%; 2 genotype 1a or 1c, 3 genotype 3a) showed highly divergent values. The analysis of 18 monitoring profiles from patients treated with PEG-IFN and Ribavirin showed similar trends, except in one case in which relapse could be predicted by HCVAg and not by HCV-RNA.

Conclusion

These results suggest that HCVAg represents an adequate tool for determining an ongoing HCV infection also in HIV co-infected patients, with lower costs and faster turnaround time than HCV-RNA.

Characteristics of HCV co-infection among HIV infected individuals from an area with high risk of blood-borne infections in central China

OBJECTIVE

Hepatitis C virus (HCV) and human immunodeficiency virus (HIV) co-infection has been proved to be a growing public health concern. The prevalence and genotypic pattern vary with geographic locations. Limited information is available to date with regard to HCV genotype and its clinical implications among those former commercial blood donor communities. The aims of this study were to genetically define the HCV genotype and associated clinical characteristics of HIV/HCV co-infected patients from a region with commercial blood donation history in central China.

METHODS

A cross sectional study, including 164 HIV infected subjects, was conducted in Shanxi province central China. Serum samples were collected and HCV antibody testing, AST and ALT testing were performed. Seropositive samples were further subjected to RT-PCR followed by direct sequence coupled with phylogenetic analysis of Core-E1 and NS5B regions performed in comparison with known reference genotypes.

FINDINGS

A total of 139 subjects were HCV antibody positive. Genotype could be determined for 88 isolates. Phylogenetic analysis revealed that the predominant circulating subtype was HCV 1b (65.9%), followed by HCV 2a (34.1%). The HCV viral load in the subjects infected with HIV1b was significantly higher than those infected with HCV 2a (P = 0.006). No significant difference for HCV RNA level was detected between ART status, CD4+ cell count level and HIV RNA level. Serum AST and ALT level were likely to increase with HCV RNA level, although no significance was observed. Those who had conducted commercial donation later than 1991 (OR 3.43, 95% CI: 1.12-10.48) and had a short duration of donation (OR 0.35, 95% CI: 0.13-0.96) were more likely to be infected with HCV 1b.

CONCLUSION

These results suggest that HCV subtype 1b predominates in this population, and the impact of HIV status and ART on HCV disease progression is not significantly correlated.

Hepatitis C treatment eligibility among HIV-hepatitis C virus coinfected patients in Oregon: a population-based sample

Approximately 287,000 individuals in the USA are coinfected with HIV and hepatitis C. Recently, new hepatitis C regimens have become available, increasing rates of sustained virologic response in the monoinfected, with studies evaluating their success in the coinfected under way. Previous investigators estimated eligibility for hepatitis C therapy among the coinfected patients, but all had significant methodological limitations. Our study is the first to use a multi-year, statewide, population-based sample to estimate treatment eligibility, and the first to estimate eligibility in the setting of an interferon-free regimen. In a population-based sample of 161 patients infected with HIV and hepatitis C living in Oregon during 2007-2010, 21% were eligible for hepatitis C therapy. Despite the anticipation surrounding an interferon-sparing regimen, eligibility assuming an interferon-free regimen increased only to 26%, largely due to multiple simultaneous contraindications. Obesity was described for the first time as being associated with decreased eligibility (OR: 0.11). Active alcohol abuse was the most common contraindication (24%); uncontrolled mental health (22%), recent injection drug use (21%), poor antiretroviral adherence (22%), and infection (21%) were also common excluding conditions. When active drug or alcohol abuse was excluded as contraindications to therapy, the eligibility rate was 34%, a 62% increase. Assuming an interferon-free regimen and the exclusion of active drug or alcohol abuse as contraindications to therapy, the eligibility rate increased to 42%. Despite the availability of direct-acting anti-viral regimens, eligibility rates in HIV-hepatitis C virus (HCV) coinfection are modest. Many factors precluding hepatitis C therapy are reversible, and targeted interventions could result in increased eligibility.

Hepatitis C virus infection in patients with HIV-1: epidemiology, natural history and management

Hepatitis C virus (HCV)-related liver diseases have contributed to increased morbidity and mortality in HIV-1-infected individuals in the era of effective antiretroviral therapy. HCV transmission patterns have changed among the HIV co-infected population during the last decade, with acute HCV infection emerging worldwide. HIV infection accelerates the progression of HCV-related liver diseases and consequently cirrhosis, liver failure, and hepatocellular carcinoma. However, the current standard treatment of HCV infection with pegylated interferon plus ribavirin results in only a limited viral response. Furthermore, cumbersome pill regimens, antiretroviral related hepatotoxicity, and drug interactions of HCV and HIV regimens complicate therapy strategies. Fortunately, in the near future, new direct-acting anti-HCV agents will widen therapeutic options for HCV/HIV co-infection. Liver transplantation is also gradually accepted as a therapeutic option for end stage liver disease of HCV/HIV co-infected patients.

The two-edged sword: vasculitis associated with HIV and hepatitis C coinfection

Vasculitis has long been associated with chronic viral infections, thus the twin perils of the infection and the immune response against it that bedevils the specialties of infection and immunity. After HIV was identified, it too became associated with vasculitic syndromes. Later, hepatitis C virus was also isolated, identified and described with its own spectrum of vasculitic diseases, including hepatitis C virus-associated cryoglobulinaemia. With the increasing prevalence of HIV and hepatitis C virus coinfection, there has come an increasing recognition of the range of vasculitides that can occur in this population leading to significant morbidity, diagnostic and treatment challenges. In this review, we examine the epidemiology, pathogenesis and general principles of treatment of these systemic diseases in HIV/hepatitis C virus coinfected individuals.

HIV and co-infections

Despite significant reductions in morbidity and mortality secondary to availability of effective combination anti-retroviral therapy (cART), human immunodeficiency virus (HIV) infection still accounts for 1.5 million deaths annually. The majority of deaths occur in sub-Saharan Africa where rates of opportunistic co-infections are disproportionately high. In this review, we discuss the immunopathogenesis of five common infections that cause significant morbidity in HIV-infected patients globally. These include co-infection with Mycobacterium tuberculosis, Cryptococcus neoformans, hepatitis B virus, hepatitis C virus, and Plasmodium falciparum. Specifically, we review the natural history of each co-infection in the setting of HIV, the specific immune defects induced by HIV, the effects of cART on the immune response to the co-infection, the pathogenesis of immune restoration disease (IRD) associated with each infection, and advances in the areas of prevention of each co-infection via vaccination. Finally, we discuss the opportunities and gaps in knowledge for future research.

Focus on drug interactions: the challenge of treating hepatitis C virus infection with direct-acting antiviral drugs in the HIV-positive patient

PURPOSE OF REVIEW

Successful treatment of hepatitis C virus (HCV) infection is necessary for the survival of HIV-infected patients. This review covers the outcomes of current therapy, first-generation HCV direct-acting antivirals (DAAs) and their drug-to-drug interactions (DDIs). Understanding DDIs between HIV antiretroviral therapy (ART) and the DAAs in development is important to assure the best management of the HIV/HCV coinfected individuals.

RECENT FINDINGS

The two first-in-class DAAs were approved for clinical use in 2011. The first trials with boceprevir or telaprevir added to standard therapy in HIV/HCV coinfected patients revealed triple therapy to be efficacious with significantly improved sustained virological response rates. However, these DAAs were associated with more and worse adverse effects, as well as with significant DDIs with multiple drugs, including ART. Early data on DAAs in development suggest improved efficacy and safety and the potential for lesser DDIs.

SUMMARY

Anti-HCV therapy is fundamental in coinfected patients, but the approved therapies are suboptimal. The first-generation of approved HCV DAAs improved efficacy of therapy in coinfected patients, but have multiple safety concerns, including potentially serious drug interactions with ART. Early results from newer DAAs are promising.

Sexually transmitted hepatitis C infection: the new epidemic in MSM?

PURPOSE OF REVIEW

Increasing evidence has emerged for permucosal transmission of hepatitis C amongst HIV-infected MSM.

RECENT FINDINGS

A rising incidence of acute hepatitis C virus (HCV) in HIV-infected MSM has been observed since 2000 in Europe, Australia, USA and Asia. Transmission appears to occur through the permucosal rather than the more usual parenteral route. Although often multifactorial, permucosal risk factors can be classified as behavioural (sexual practices and mucosally administered drugs) and biological (HIV and sexually transmitted infections). This review will describe the epidemiology of HCV infection in this cohort. Current and future treatment strategies will also be outlined in the context of novel, orally bioavailable, directly acting antiviral therapies.

SUMMARY

An improved understanding of HCV epidemiology will allow implementation of more effective public health interventions to limit onward transmission of HCV.

Acute hepatitis C in an HIV-infected patient: a case report and review of literature

With the decrease in transmission via transfusions and injection drug use, acute symptomatic hepatitis C is infrequently seen in developed countries. We report a case of a human immunodeficiency virus (HIV)-infected adult who presented with abdominal pain. His alanine aminotransferase was greater than sixty times the upper limit of normal without any evidence on examination of fulminant hepatic failure. His workup revealed an elevated hepatitis C viral level with a negative hepatitis C antibody. He was discharged once his liver function tests improved. As an outpatient, he had a recurrent bout of symptoms with an elevation of his alanine aminotransferase and hepatitis C viral levels that promoted anti-hepatitis C virus treatment. This case illustrates the importance of considering acute hepatitis C as a cause of acute hepatitis in HIV-infected men who have sex with men. While patients with acute symptomatic hepatitis C generally have a higher rate of spontaneous viral clearance compared to those with an insidious acute infection, most still progress to chronic hepatitis C infection, and patients with HIV coinfection carry a higher risk of progression to chronic disease.