New antivirals for the treatment of chronic hepatitis B.

INTRODUCTION: Current treatment with oral nucleos(t)ides entecavir or tenofovir provide sustained suppression of HBV replication and clinical benefit in most chronic hepatitis B virus (HBV) infected persons. However, HBV rebound generally occurs upon drug discontinuation due to persistence of genomic HBV reservoirs as episomic cccDNA and chromosomic integrated HBV-DNA. There is renewed enthusiasm on HBV drug discovery following recent successes with antivirals for hepatitis C and immunotherapies for some cancers. Areas covered: New drugs that target distinct steps of the HBV life cycle are been developed, including inhibitors of viral entry, new polymerase inhibitors, capsid and assembly inhibitors, virus release blockers, and disruptors of cccDNA formation and transcription. Alongside these antivirals, agents that enhance anti-HBV specific immune responses are being tested, including TLR agonists, checkpoint inhibitors and therapeutic vaccines. Expert opinion: The achievement of a 'functional cure' for chronic HBV infection, with sustained HBsAg clearance and undetectable viremia once medications are stopped, represents the next step in the pace towards HBV elimination. Hopefully, the combination of new drugs that eliminate or functionally inactivate the genomic HBV reservoirs (cccDNA and integrated HBV-DNA) along with agents that enhance or activate immune responses against HBV will lead to a 'definitive cure' for chronic HBV infection.

HTLV infection in HCV-antibody positive patients in Spain.

Since hepatitis C virus (HCV) and human T-lymphotropic virus (HTLV) share transmission routes, dual infection could be frequent. In Spain, HTLV underdiagnosis is highlighted by the high proportion of patients presenting either with tropical spastic paraparesis (TSP) or adult T-cell leukemia (ATL) at first diagnosis. We examined whether the renewed efforts for expanding HCV testing may provide a sentinel population that might selectively be targeted to unveil asymptomatic HTLV carriers. The presence of anti-HTLV antibodies was examined in 3,838 consecutive individuals with reactive HCV serology attended during the last three years at 13 hospitals distributed across the Spanish geography. Overall 71% were male and the median age was 41-years old. Foreigners represented 9% of the study population. A total of 50 individuals (1.3%) were seroreactive for HTLV, being 30 confirmed as HTLV-2 and two as HTLV-1 (0.12%). The remaining 18 had indeterminate Western blot patterns. Most individuals with HTLV-2 and HTLV indeterminate serology were HIV-positive, former injection drug users and native Spaniards. In contrast, the two HTLV-1 infections were found in men coming from Brazil and the Dominican Republic, respectively. In summary, the overall prevalence of HTLV infection in individuals living in Spain seropositive for HCV is 1.3%, more than 10-fold greater than in general outclinics in Spain. However, immigrants from HTLV-1 endemic regions and former injection drug users with HTLV-2 infection are by far the major contributory groups in HCV patients. Therefore, testing for HTLV in newly diagnosed HCV individuals would not contribute much to improve late HTLV diagnosis in Spain.

Hepatitis delta and HIV infection.

Viral liver diseases are frequent comorbidities and major contributors to death in HIV-positive individuals on antiretroviral therapy. Although cure of hepatitis C and control of hepatitis B with antivirals avert liver disease progression in most HIV-coinfected patients, the lack of satisfactory treatment for hepatitis delta virus (HDV) infection remains a major threat for developing cirrhosis and liver cancer in this population. In the European Union (EU) and North America, sexual contact has replaced injection drug use that has been the major transmission route for HDV in HIV-positive persons. PegIFNα is the only approved HDV therapy; however, sustained HDV-RNA clearance is achieved by less than 25%. The recent discovery of sodium taurocholate cotransporting polypeptide as the key hepatitis B virus (HBV) and HDV cell entry receptor has opened the door to a new therapeutic era. Indeed, promising results have been released using Myrcludex-B, a sodium taurocholate cotransporting polypeptide inhibitor. More encouraging are data with new classes of HDV blockers, such as prenylation inhibitors (i.e. lonafarnib) and nucleic acid polymers. At this time, sustained suppression of HDV replication is the primary goal of HDV therapy, as it is associated with normalization of liver enzymes and histological improvement. Of note, the use of specific antivirals for HDV must be given along with anti-HBV agents to prevent HBV rebounds following removal of viral interference. The lack of persistent forms of HDV-RNA could provide a unique opportunity for curing hepatitis delta, even without eliminating HBV circular covalently closed DNA. Ultimately, suppression of HDV replication along with hepatitis B surface antigen clearance once drugs are off would be the best reflect of hepatitis delta cure.

Hepatitis C cure with antiviral therapy--benefits beyond the liver.

Liver disease is the major complication of chronic HCV infection. However, extrahepatic complications are common (50-75%), including mixed cryoglobulinaemia and B-cell lymphomas. Given that chronic hepatitis C has become curable using expensive oral direct-acting antivirals (DAAs), it seems worth revisiting the whole spectrum and burden of disease in HCV carriers.Herein, we update the most clinically significant medical complications associated with chronic hepatitis C and the evidence of benefits that would derive from a wide use of curative DAA therapies.Chronic HCV infection is associated with a broad spectrum of clinical conditions, including distinct rheumatic disorders (polyarthritis, sicca syndrome), lymphoproliferative conditions (mixed cryoglobulinaemia, monoclonal gammapathies and B-cell lymphomas) and damage at other organs due to persistent systemic inflammation, leading to renal, bone, neurological and/or cardiovascular disease. Eradication of HCV with DAAs is associated with amelioration and/or resolution of most liver-related and extrahepatic complications. Ultimately, gains in quality of life and survival favour treating everyone with hepatitis C regardless of liver fibrosis stage.

Emerging challenges in managing hepatitis B in HIV patients.

Roughly 10 % of HIV-positive individuals worldwide have concomitant chronic hepatitis B virus (HBV) infection, with large differences between geographical regions and/or risk groups. Hepatitis B is a preventable infection with vaccines. However, it cannot be eradicated once acquired, resembling HIV and in contrast with HCV. In developed countries, hepatitis B exhibits particular features in the HIV population. First, HBV infection is less frequently misdiagnosed than in the general population. Second, nucleos(t)ide analogs active against HBV are widely used as part of antiretroviral combinations and are taken by most HIV patients. Lastly, as the HIV population ages given the success of antiretroviral therapy, non-AIDS co-morbidities are becoming a major cause of disease, for which specific drugs are required, increasing the risk of interactions and hepatotoxicity. Furthermore, concern on HBV reactivation is rising as immunosuppressive drug therapies are increasingly been used for cancers and other non-malignant conditions. In this scenario, new challenges are emerging in the management of hepatitis B in HIV-positive individuals. Among them, major interest is focused on failures to suppress HBV replication, HBV breakthroughs and reactivations, the meaning of isolated anti-HBc, screening for liver cancer, and the complexity arising when hepatitis viruses C and/or D are additionally present. This review will focus on these challenges and the major advances in HBV coinfection in HIV.

Drug interactions with new hepatitis C oral drugs.

INTRODUCTION: Chronic hepatitis C virus (HCV) infection has recently become a curable disease with antiviral therapy. The knowledge of drug interactions using direct-acting antivirals (DAA) may permit maximizing antiviral efficacy and avoiding drug-related toxicities. Ageing in the chronic hepatitis C population, along with added co-morbidities that require other medications, has increased the attention on drug interactions using DAA. AREAS COVERED: This review provides an update of the most clinically significant pharmacokinetic and pharmacodynamic drug interactions occurring between currently available DAA and other medications. The review also revisits how drug interactions with DAA can be prevented and managed. EXPERT OPINION: Interactions between DAA and other drugs are frequent in clinical practice. The most frequent drug interactions modify drug metabolism by inducing or inhibiting the cytochrome P450, leading to abnormal drug exposures. Through this mechanism HCV protease inhibitors, especially when co-formulated with ritonavir as pharmacoenhancer, and non-nucleoside HCV polymerase inhibitors interact with other medications. In contrast, NS5B nucleos(t)ide analog inhibitors (i.e., sofosbuvir) and some HCV NS5A inhibitors (i.e., ledipasvir), which do not or only marginally affect CYP450, are relatively free of significant pharmacokinetic interactions. However, exposure to HCV nucleos(t)ide analogs may be influenced by induction/inhibition of drug transporters (i.e., P-glycoprotein) as well as by pharmacodynamic interference with other nucleos(t)ide analogs used as antivirals or cancer drugs. Drug interactions for some NS5A inhibitors (i.e., daclatasvir) are generally moderate and can be managed with dose adjustments.

Liver fibrosis progression despite HCV cure with antiviral therapy in HIV-HCV-coinfected patients.

BACKGROUND: Accelerated liver fibrosis and more frequent hepatic decompensation events and liver-related deaths are characteristically seen in chronic hepatitis C patients coinfected with HIV compared with HCV-monoinfected individuals. Quantitative estimates of long-term clinical benefits derived from curing HCV with antiviral therapy in coinfected patients are scarce, despite being needed for accurate cost-effectiveness decisions using expensive direct-acting antivirals in this population. METHODS: We retrospectively examined all HIV-HCV-coinfected patients followed at one reference clinic in Madrid since 2004. Liver fibrosis was measured longitudinally using elastometry; changes above 30% in kilopascal units were considered as significant. RESULTS: A total of 568 HIV-HCV-coinfected patients were examined. Pegylated interferon/ribavirin therapy had been given to 396 (69.7%) of whom 138 (34.8%) had achieved sustained virological response (SVR). Mean follow-up was of 6.8 (±1.5) years for hepatic events and 4.4 (±0.8) years for liver fibrosis. Hepatic decompensation events, liver-related deaths and significant liver fibrosis progression occurred less frequently in SVR than in non-treated/treatment failures. Although regression of liver fibrosis occurred in most SVR patients, fibrosis significantly progressed in 7.2% of them, in association with higher plasma HIV RNA (P=0.005) and longer exposure to HIV protease inhibitors (P=0.009). CONCLUSIONS: Achievement of SVR dramatically reduces the risk of hepatic decompensation events and liver-related deaths in HIV-HCV-coinfected patients. Although liver fibrosis generally improves following HCV cure, worsening may occur in association with uncontrolled HIV replication and prolonged exposure to protease inhibitors. Thus, periodic assessment of liver fibrosis is warranted after SVR and screening for liver cancer should continue in coinfected patients with advanced liver fibrosis.

Pharmacogenetics of antiretroviral therapy.

INTRODUCTION: Human genetic testing is rapidly entering into most medical disciplines, mainly as a way to predict hereditary conditions including predisposition to cancers or degenerative diseases. Another area of interest for human genomics is to ascertain the therapeutic effect and prevent potential toxicities and/or drug-drug interactions of medication. AREAS COVERED: Several human genotypes have been associated with differences in the metabolism and transport of antiretroviral agents that ultimately affect drug exposure. The accelerated discovery of new gene mutations and polymorphisms that influence the effects of antiretroviral drugs provides a unique opportunity for a personalized medicine approach in the management of lifelong HIV therapy. EXPERT OPINION: Integration of human genomic screening into HIV clinical management will be cost-effective, maximizing the benefit of drugs with the lowest risk of side effects for a given patient.

Molecular epidemiology and clinical features of human T cell lymphotropic virus type 1 infection in Spain.

Human T cell lymphotropic virus type 1 (HTLV-1) infection in Spain is rare and mainly affects immigrants from endemic regions and native Spaniards with a prior history of sexual intercourse with persons from endemic countries. Herein, we report the main clinical and virological features of cases reported in Spain. All individuals with HTLV-1 infection recorded at the national registry since 1989 were examined. Phylogenetic analysis was performed based on the long terminal repeat (LTR) region. A total of 229 HTLV-1 cases had been reported up to December 2012. The mean age was 41 years old and 61% were female. Their country of origin was Latin America in 59%, Africa in 15%, and Spain in 20%. Transmission had occurred following sexual contact in 41%, parenteral exposure in 12%, and vertically in 9%. HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) was diagnosed in 27 cases and adult T cell leukemia/lymphoma (ATLL) in 17 subjects. HTLV-1 subtype could be obtained for 45 patients; all but one belonged to the Cosmopolitan subtype a. One Nigerian pregnant woman harbored HTLV-1 subtype b. Within the Cosmopolitan subtype a, two individuals (from Bolivia and Peru, respectively) belonged to the Japanese subgroup B, another two (from Senegal and Mauritania) to the North African subgroup D, and 39 to the Transcontinental subgroup A. Of note, one divergent HTLV-1 strain from an Ethiopian branched off from all five known Cosmopolitan subtype 1a subgroups. Divergent HTLV-1 strains have been introduced and currently circulate in Spain. The relatively large proportion of symptomatic cases (19%) suggests that HTLV-1 infection is underdiagnosed in Spain.

Progression to advanced liver fibrosis in HIV-HCV-coinfected patients and prioritization of new hepatitis C therapies.

BACKGROUND: Because of their high cost, the use of direct-acting antivirals (DAAs) is being restricted by many governments to chronic HCV-infected individuals with advanced liver fibrosis. However, response rates are lower and toxicities more frequent in this subset of patients. METHODS: All HIV-HCV-coinfected patients followed for at least 3 years at one reference clinic were identified. Liver fibrosis progression (LFP) was defined as a shift from Metavir F0-F2 to F3-F4 estimates (>9.5 KPa) using elastometry. RESULTS: A total of 527 HIV-HCV-coinfected patients were identified, of whom 344 had F0-F2 at baseline. Pegylated interferon/ribavirin therapy was given to 205 patients with null/mild fibrosis, of whom 92 (44.9%) achieved sustained virological response (SVR). After a mean follow-up of 53 months, LFP occurred in 5.4% SVR, 25.7% non-SVR and 18% untreated patients (P=0.005). In multivariate analysis, only achievement of SVR prevented LFP (adjusted hazard ratio 2.1; 95% CI 1.1, 4.1; P=0.01). In 139 untreated patients, only greater baseline elastometry values predicted LFP in multivariate analysis (adjusted hazard ratio 1.84; 95% CI 1.03, 3.3; P=0.03). The area under the receiver operating characteristic (AUROC) curve was 79%. A discriminant threshold of 7.1 kPa gave 68% sensitivity and 82% specificity. CONCLUSIONS: In the absence of successful treatment, more than 20% of HIV-HCV-coinfected patients with null/mild liver fibrosis progress to advanced fibrosis within 5 years. Patients with >7.1 kPa (Metavir F2) display the highest risk. Therefore, all coinfected patients with any significant liver fibrosis should be considered as candidates for new DAA-based therapies.

Management and treatment of chronic hepatitis B in HIV-positive patients.

Chronic hepatitis B virus (HBV) infection is common in HIV-positive individuals, mainly among those with sexually risky behaviors. Although HBV vaccination is mandatory in all HIV-infected persons with negative HBV markers, lower rates of protection due to abnormal immune responses are achieved. HIV accelerates the course of liver disease caused by chronic HBV infection, leading rapidly to end-stage hepatic illness and increasing the risk of hepatocellular carcinoma. Treatment of HIV including nucleos(t)ide analogues active against HBV highly improves outcomes, especially when tenofovir is part of the antiviral regimen. The use of lamivudine as the only active anti-HBV agent in HIV-HBV co-infected patients should be limited to individuals with low serum HBV-DNA levels. Otherwise, selection of drug resistance may eliminate any clinical benefit, produce cross-resistance to other antivirals, and favor the emergence of HBV vaccine escape mutants.

Hepatitis delta is a major determinant of liver decompensation events and death in HIV-infected patients.

BACKGROUND: Coinfection with hepatitis viruses is common in individuals infected with human immunodeficiency virus (HIV) and has become a leading cause of complications and death in those receiving antiretroviral therapy (ART). METHODS: We retrospectively examined the effect of coinfection with hepatitis B, C, and/or D viruses (HBV, HCV, HDV, respectively) on liver decompensation events (ascites, variceal bleeding, encephalopathy, and/or hepatocellular carcinoma) and liver-related mortality in HIV-positive patients on regular follow-up since the year 2004 at a reference HIV clinic in Madrid, Spain. RESULTS: A total of 1147 HIV-infected patients (mean age, 42 years; 81% males; 46% intravenous drug users, 85.4% on ART) were analyzed. Mean follow-up was 81.2 ± 17.8 months. At baseline, 521 patients (45.4%) were HCV-antibody positive, 85 (7.4%) were hepatitis B surface antigen positive, and 17 (1.5%) were anti-HDV positive. A total of 233 HIV/HCV-coinfected patients received antiviral therapy for HCV, of whom 106 (45%) achieved sustained virologic response (SVR). Overall, 15 patients died of liver-related complications and 26 developed hepatic decompensation events. Taking as controls the 524 HIV-monoinfected patients, HDV coinfection (adjusted hazard ratio [AHR], 7.5; 95% confidence interval [CI], 1.84-30.8; P = .005) and baseline liver stiffness (AHR, 1.1; 95% CI, 1.07-1.13; P < .0001) were associated with a higher rate of liver-related morbidity and mortality. In contrast, SVR following hepatitis C therapy in HIV/HCV-coinfected patients was protective (AHR, 0.11; 95% CI, .01-.86; P = .03). CONCLUSIONS: Hepatitis delta is associated with a high rate of death and liver decompensation events in HIV-infected patients on ART.

Longitudinal changes in viral RNA concentration in patients with chronic hepatitis C and/or HIV infection in the absence of antiviral therapy.

BACKGROUND: The concentration of circulating viral RNA at baseline and during antiviral therapy predicts response in both HIV infection and chronic hepatitis C. METHODS: Retrospective review of longitudinal plasma HCV-RNA determinations in untreated chronic hepatitis C patients. As comparison, longitudinal plasma HIV-RNA measurements were performed in untreated HIV individuals. RESULTS: A total of 3169 HCV-RNA determinations over 43.0±31.6 months were available for 818 chronic hepatitis C patients. For 333 HIV individuals, 1998 HIV-RNA measurements were examined over 27.3±17.5 months. Overall 44% consecutive specimens had >0.5 log variation in HCV-RNA values compared to 23% for HIV-RNA (p<0.001). These rates were 15% and 4%, respectively, for variations >1 log (p<0.001). In multivariate analysis (odds ratio, 95% confidence interval, p), the likelihood of experiencing HCV-RNA variations >0.5 log IU/mL was greater in patients with lower HCV-RNA (0.35 per log[0.26-0.47], 0.001), HIV coinfection (2.57[91.56-4.23], <0.001) and IL28B-CC (1.87[1.28-2.74], 0.001). CONCLUSIONS: Fluctuation in circulating HCV-RNA may be clinically meaningful in a substantial proportion of chronic hepatitis C patients. It may influence the best time to prescribe antiviral therapy. Moreover, decisions based on early viral kinetics, such as early stopping rules, may require testing of baseline specimens the closest to treatment initiation.

Hepatitis B in HIV-infected patients.

Chronic hepatitis B virus (HBV) infection is common in HIV-positive individuals. Although HBV vaccination is mandatory for HIV-positive individuals with negative-HBV markers, lower rates of protection are achieved. HIV infection accelerates the course of liver disease caused by chronic HBV infection, leading to end-stage hepatic illness and increasing the risk of hepatocellular carcinoma. Anti-HBV active agents, especially tenofovir, improve outcomes. Lamivudine alone should be limited to patients with low serum HBV-DNA levels, since selection of drug resistance often compromises long-term benefits, leads to cross-resistance with other antivirals, and favors the potential emergence of HBV-vaccine escape mutants.

Update on HIV/HCV coinfection.

Liver disease is currently one of the leading causes of hospitalization and death in HIV-positive individuals. Coinfection with the hepatitis C virus (HCV) is a major contributor to this trend. Besides hepatic damage, which is enhanced in the presence of HIV-associated immunosuppression, HCV may contribute to disease in coinfected individuals by potentiating immune activation and chronic inflammation, which ultimately account for an increased risk of cardiovascular events, kidney disease, and cancers in this population. Fortunately, hepatitis C therapeutics has entered a revolutionary era in which we hope that most patients treated with the new oral direct-acting antivirals (DAA) will be cured. However, many challenges preclude envisioning a prompt elimination of HCV from the coinfected population. Issues that should be addressed include the following: (1) rising incidence of acute hepatitis C in men who have sex with men, and expansion/recrudescence of injection drug use in some settings/regions; (2) adverse drug interactions between antiretrovirals and DAA; and (3) high cost of DAA, which may lead many to defer or fail to access appropriate therapy.

Association between HLA alleles and HAM/TSP in individuals infected with HTLV-1.

HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) develops in less than 5 % of HTLV-1 carriers. It is unclear which factors trigger the development of disease. The aim of this study was to explore the influence of HLA alleles on the development of HAM/TSP. A total of 40 HTLV-1-infected individuals belonging to the Spanish HTLV-1 cohort were examined. HTLV-1 proviral load was measured by real-time polymerase chain reaction. HLA class I (A, B, C) and class II (DRB1, DQB1) alleles were genotyped using the bead array technology. Median HTLV-1 proviral load in 12 HAM/TSP patients was greater than in 28 asymptomatic carriers (637 vs. 71 copies per 10(4) peripheral blood mononuclear cells; p = 0.006). Moreover, HAM/TSP was significantly associated with HLA-B 07 and HLA-DRB1 01:01 (p = 0.039). Interestingly, individuals with these HLA alleles had greater HTLV-1 proviral load than asymptomatic carriers (p = 0.036). In summary, HLA testing should be considered in asymptomatic HTLV-1 individuals and close monitoring of HTLV-1 proviral load along with periodic neurological evaluations should be prioritized in HLA-DRB1 01:01 and HLA-B 07 carriers.

Genetic determinants of idiopathic noncirrhotic portal hypertension in HIV-infected patients.

BACKGROUND: Noncirrhotic portal hypertension (NCPH) is a rare but potentially life-threatening complication in patients with human immunodeficiency virus (HIV). Cases of NCPH have been reported in HIV-negative individuals as result of treatment with thiopurines for leukemia or inflammatory bowel disease. Exposure to didanosine, which is also a purine analogue, predisposes to NCPH in the HIV setting. However, it is unclear why NCPH only develops in a small subset of didanosine-treated patients. METHODS: A multicenter, case-control study was conducted to investigate the role of pharmacogenomics in NCPH in HIV patients with prior didanosine exposure. Three controls were chosen for each case, adjusted for sex, age, CD4 counts, plasma HIV-RNA, and site. Tagging 36 single-nucleotide polymorphisms (SNPs) at enzymes involved in the purine metabolism (inosine triphosphatase, 5'-nucleotidase cytosolic-II, purine nucleoside phosphorylase and xanthine oxidase) was performed using SNPlex microarray technology. RESULTS: Eighty individuals were examined; 22 with NCPH and 58 matched controls. Two SNPs at the 5'-nucleotidase gene were associated with NCPH: rs11191561 (48% CG/GG vs 17% CC; P=.003) and rs11598702 (40% CC/CT vs 9% TT; P=.003). SNPs at another 2 loci at the xanthine oxidase gene were also associated with NCPH: rs1429376 (71% AA vs 23% CC/AC; P=.015) and rs1594160 (71% AA vs 23% CC/AC; P=.015). There was a cumulative risk of NCPH for these 4 SNPs: 7%, 26%, 42%, 50%, and 100%, respectively, for 0, 1, 2, 3, or all SNPs (P=.001). CONCLUSIONS: SNPs at the 5'-nucleotidase and xanthine oxidase genes influence the risk of NCPH in HIV patients treated with didanosine.

HIV Gag-specific immune response mediated by double negative (CD3(+)CD4(-)CD8(-)) T cells in HIV-exposed seronegative individuals.

Double negative (DN) T cells are CD3(+), CD4(-), CD8(-) cells with either T-cell receptors (TCR) αß or TCR γδ whose importance on protection against HIV infection is unknown. Since HIV-exposed seronegative individuals correspond to an ideal group in whom correlates of protection are expected, the role of these cells was studied in 13 HIV-serodiscordant couples in a stable relationship and reporting unprotected sexual intercourses. HIV-specific immune responses mediated by DN T-cells were evaluated by measuring intracellular IFNγ and MIP1ß (CCL4) production in response to HIV-Gag peptides. Thirty-five healthy controls not exposed to HIV were tested similarly and used to define a threshold for positive responses. Interestingly, Gag-specific DN T-cell responses were found in 3/13 (23%) HIV-exposed seronegative individuals (Group A), involving both DN/αß(+) and DN/γδ(+) T-cells through MIP1ß and IFNγ production. 4/13 (30%) of partners infected with HIV (Group B) also showed Gag-specific responses but were mediated exclusively by DN/γδ(+) T-cells, mainly through IFNγ production. DN T-cells in Group A individuals can display differential HIV-specific immune responses, which might contribute to the low susceptibility to infection with HIV shown by individuals in Group A.

Interferon-stimulated genes are associated with peginterferon/ribavirin treatment response regardless of IL28B alleles in hepatitis C virus/HIV-coinfected patients.

BACKGROUND: The interaction between interferon-stimulated genes (ISGs) expression, IL28B genotypes and hepatitis C treatment outcomes has been mainly evaluated in the liver tissue from hepatitis C virus (HCV)-monoinfected patients but with controversial results. Herein, we examined whether more easily accessible peripheral blood mononuclear cells (PBMCs) could be used for this purpose in HIV-HCV coinfected patients, a population in whom HCV-induced liver disease progression occurs more rapidly and treatment response is lower. METHODS: Gene expression profiles were examined using the human whole genome Agilent microarray platform in PBMCs collected from HIV/HCV-coinfected patients who had completed a course of peginterferon/ribavirin therapy with validated outcomes. Patients were split out according to the achievement of sustained virological response (SVR) and IL28B rs12979860 genotypes. The GeneSpringGX software was used to select genes differentially expressed in the different groups. RESULTS: Nineteen HIV/HCV-coinfected individuals receiving antiretroviral therapy and having undetectable plasma HIV-RNA were examined. Global gene expression profiles showed 42 genes differentially expressed according to treatment outcome and 56 according to IL28B genotype. Common genes were not found and functions differed for genes belonging to either group. Whereas at least 26 out of 37 repressed genes (70.3%) in SVR patients were ISGs, none of the 56 differentially expressed genes in carriers of distinct IL28B variants were ISGs (P < 0.0001). CONCLUSION: Baseline expression of ISGs in PBMCs from HCV/HIV-coinfected patients influence the response to peginterferon/ribavirin therapy, regardless of IL28B genotypes. PBMC specimens can reliably be used for evaluating ISGs expression in clinical practice.

Different impact of IL28B polymorphisms on response to peginterferon-α plus ribavirin in HIV-positive patients infected with HCV subtypes 1a or 1b.

BACKGROUND: HCV subtype 1a has emerged as a predictor of poor response to triple hepatitis C therapy including boceprevir or telaprevir, which largely has been attributed to a lower resistance barrier in HCV-1a compared to -1b. OBJECTIVES: We examined whether a lower efficacy of pegIFN/RBV on HCV-1a than HCV-1b could alternatively contribute to explain it. STUDY DESIGN: All chronic hepatitis C patients who had completed a course of pegIFN/RBV therapy at our institution were examined. For this study we selected individuals that were IFN-naïve and had been successfully subtyped as 1a or 1b. Moreover, only HIV-coinfected patients were included as they represented a more uniform population in terms of demographics and treatment exposure at our institution. The IL28B rs12979860 alleles were typed using the 5' nuclease assay. RESULTS: A total of 96 individuals were examined, 58 of whom harbored HCV-1a and 38 HCV-1b. IL28B allele distribution was as follows: 33 CC and 63 CT/TT. SVR was achieved by 64% of CC vs 30% of CT/TT patients (p=0.001). On the other hand, SVR was 53% in HCV-1b vs 34% in HCV-1a (p=0.08). Interestingly, the effect of IL28B variants on SVR was mainly recognized in HCV-1a (63% in CC vs 20% in CT/TT; p=0.001), being marginal on HCV-1b (64% in CC vs 46% in CT/TT; p=0.27). CONCLUSIONS: The rate of SVR to pegIFN/RBV therapy tends to be lower in HIV-infected patients with chronic hepatitis C due to HCV-1a than HCV-1b; being the impact of IL28B variants significantly stronger on HCV-1a than HCV-1b.