September 25, 2013

British Columbia steps up measures to address viral hepatitis

September 25, 2013 3:45 pm

BC-Infection-300x196

Dr. Julio Montaner is the director of the British Columbia Centre for Excellence in HIV/AIDS at St. Pauls’ Hospital.

A model for HIV treatment and prevention developed by the British Columbia Centre for Excellence (BC-CfE) in HIV/AIDS at St. Paul’s Hospital may also be the key to changing the course of the province’s hepatitis epidemics.

In March, the government of British Columbia announced the creation of a $1.5-million fund through St. Paul’s Hospital Foundation, which will enable the BC-CfE to explore ways to better address hepatitis B and C.

“With the support of the government of BC, we have led the way in the fight against HIV/AIDS. Now we hope to do the same with viral hepatitis,” said Dr. Julio Montaner, director, BC-CfE. “What we have done for HIV can and should be done for other high burden diseases like hepatitis. We can take the infrastructure we have developed under STOP HIV/AIDS and apply that so we can deliver a hepatitis-free generation to our province.”

Following the model pioneered by the BC-CfE, this project will focus on determining vulnerable individuals, identifying the best ways to prevent new infections and engage those at-risk or living with the diseases, and assessing the reach and effectiveness of new antiviral treatments.

Viral hepatitis affects thousands of British Columbians, many of whom are unaware they even have the disease. The BC Centre for Disease Control estimates that approximately 80,000 British Columbians are living with hepatitis C and 60,000 are living with hepatitis B.

Both viruses infect the liver and can lead to permanent damage, including liver cancer and failure. In many cases, no symptoms appear until the person’s liver is severely damaged.

“This funding will increase awareness and help us set up a province-wide strategy to combat these epidemics,” said Dr. Mel Krajden, medical director, hepatitis services, at BC Centre for Disease Control and professor of pathology and laboratory medicine, UBC.

Article By:

Sarah Rapplinger Sarah Rapplinger is a communications coordinator with the St. Paul’s Hospital Foundation in BC.

Source

Antimicrob. Agents Chemother. October 2013 vol. 57 no. 10 4727-4735

Dominique Larreya, Ansgar W. Lohseb, Christian Trepoc, Jean-Pierre Bronowickid, Keikawus Arastéhe, Marc Bourlièref, Jose Luis Callejag, Jerry O. Sternh, Gerhard Nehmizi, Nasri Abdallahj, Kristi L. Bergerk, Martin Marquisk, Jürgen Steffgeni and  George Kukoljk for the BI 207127 Study Group

+ Author Affiliations

ABSTRACT

Deleobuvir (BI 207127) is an investigational oral nonnucleoside inhibitor of hepatitis C virus (HCV) NS5B RNA polymerase. Antiviral activity, virology, pharmacokinetics, and safety were assessed in HCV genotype 1-infected patients receiving 5 days' deleobuvir monotherapy. In this double-blind phase 1b study, treatment-naive (TN; n = 15) and treatment-experienced (TE; n = 45) patients without cirrhosis received placebo or deleobuvir at 100, 200, 400, 800, or 1,200 mg every 8 h (q8h) for 5 days. Patients with cirrhosis (n = 13) received deleobuvir at 400 or 600 mg q8h for 5 days. Virologic analyses included NS5B genotyping and phenotyping of individual isolates. At day 5, patients without cirrhosis had dose-dependent median HCV RNA reductions of up to 3.8 log10 (with no placebo response); patients with cirrhosis had median HCV RNA reductions of approximately 3.0 log10. Three patients discontinued due to adverse events (AEs). The most common AEs were gastrointestinal, nervous system, and skin/cutaneous tissue disorders. Plasma exposure of deleobuvir was supraproportional at doses ≥ 400 mg q8h and approximately 2-fold higher in patients with cirrhosis than in patients without cirrhosis. No virologic breakthrough was observed. NS5B substitutions associated with deleobuvir resistance in vitro were detected in 9/59 patients; seven encoded P495 substitutions, including P495L, which conferred 120- to 310-fold-decreased sensitivity to deleobuvir. P495 variants did not persist in follow-up without selective drug pressure. Deleobuvir monotherapy was generally well tolerated and demonstrated dose-dependent antiviral activity against HCV genotype 1 over 5 days.

FOOTNOTES

Received 15 March 2013. Returned for modification 2 May 2013. Accepted 9 July 2013.

Address correspondence to Dominique Larrey, dom-larrey@chu-montpellier.fr.

Published ahead of print 15 July 2013

Supplemental material for this article may be found at http://dx.doi.org/10.1128/AAC.00565-13

Source.

Pharmacoepidemiology and Drug Safety

Early View (Online Version of Record published before inclusion in an issue)

Brief Report

E. Jennifer Edelman1,2,‡,*, Kirsha S. Gordon3,‡, Vincent Lo Re III4,5, Melissa Skanderson3,6, David A. Fiellin1,2, Amy C. Justice1,2,3, for the VACS Project Team

Article first published online: 22 SEP 2013

DOI: 10.1002/pds.3517

Copyright © 2013 John Wiley & Sons, Ltd.

Keywords: acetaminophen; HIV; hepatitis C; Veterans; medication; pharmacoepidemiology

ABSTRACT

Purpose

HIV-infected patients may be at particular risk for acetaminophen-induced hepatotoxicity, but acetaminophen use in the context of liver injury has been incompletely examined among HIV-infected patients. Among a sample of HIV-infected patients, we aimed to determine acetaminophen exposure, assess the cross-sectional association between acetaminophen exposure and advanced hepatic fibrosis, and determine whether factors associated with acetaminophen exposure varied by HCV status.

\Methods

We conducted a cross-sectional analysis of the Veterans Aging Cohort Study. Advanced hepatic fibrosis was defined as a FIB-4 > 3.25, a composite score calculated based on age, alanine aminotransferase, aspartate aminotransferase, and platelet count. Multivariable ordered polytomous logistic regression was used to determine the association between FIB-4 status and acetaminophen exposure stratified by HCV status.

Results

Among HIV-infected patients (n = 14 885), 31% received at least one acetaminophen prescription. Among those receiving acetaminophen, acetaminophen overuse was common among both HIV-monoinfected and HIV/HCV-coinfected patients (846 [31%] vs 596[32%], p = 0.79). After stratifying by HCV status, those with evidence of advanced liver fibrosis were equally likely to be exposed to acetaminophen. Furthermore, HIV-monoinfected patients with an alcohol use disorder were more likely to have acetaminophen overuse (OR [95%CI] = 1.56 [1.21–2.02]).

Conclusions

Strategies to minimize acetaminophen exposure, especially for HIV-monoinfected patients, are warranted. Copyright © 2013 John Wiley & Sons, Ltd.

Source

World J Gastroenterol. 2013 September 21; 19(35): 5917-5924.

Published online 2013 September 21. doi: 10.3748/wjg.v19.i35.5917.

Copyright ©2013 Baishideng Publishing Group Co., Limited. All rights reserved.

Livia Melo Villar, Elisabeth Lampe, Laboratory of Viral Hepatitis, Oswaldo Cruz Institute, Fiocruz, Rio de Janeiro, RJ 210360-040, Brazil

José Antonio Del Campo, Isidora Ranchal, Manuel Romero-Gomez, Unit for the Clinical Management of Digestive Diseases and CIBERehd, Hospital Universitario de Valme, 41014 Sevilla, Spain
Author contributions: Villar LM and Romero-Gomez M contributed to the study concept and design; Villar LM, Del Campo JA and Ranchal I performed data extraction, analysis and interpretation of the data; Lampe E and Romero-Gomez M drafted the review; all authors have read and approved the paper.

Correspondence to: Livia Melo Villar, PhD, Viral Hepatitis Laboratory, Helio and Peggy Pereira Pavillion, Ground Floor, Room B09, FIOCRUZ Av. Brasil, 4365, Manguinhos, Rio de Janeiro, RJ 210360-040, Brazil. lvillar@ioc.fiocruz.br

Telephone: +55-21-25621918 Fax: +55-21-22706397

Received December 14, 2012; Revised January 31, 2013; Accepted February 9, 2013;

Abstract

AIM: To evaluate the association between 25-hydroxyvitamin D [25(OH)D] and sustained virological response (SVR) in hepatitis C virus (HCV) infected individuals.

METHODS: Relevant studies were identified by systematically searching MEDLINE databases up to March 2012 and abstracts of the European and American Congress of Hepatology conducted in 2011. Studies must provide information on SVR and the levels of 25(OH)D3 and/or 25(OH)D2 [henceforth referred to as 25(OH)D] in sera samples from HCV infected individuals. The inclusion criteria were: clinical studies that included HCV infected patients aged older than 18 years regardless of HCV genotype or ethnic group; provided information on SVR rates; and were reported in the English language as full papers. Due to the heterogeneity of studies in categorizing serum vitamin D levels, a cut-off value of 30 ng/mL of serum 25(OH)D was used. Heterogeneity was assessed using I2 statistics. The summary odds ratios with their corresponding 95%CI were calculated based on a random-effects model.

RESULTS: Overall, 11 studies (8 observational and 3 interventional) involving 1575 individuals were included and 1117 HCV infected individuals (71%) showed low vitamin D levels. Most of the studies included mono-infected HCV individuals with the mean age ranging from 38 to 56 years. Four studies were conducted in human immunodeficiency virus/HCV infected individuals. Regarding vitamin D measurement, most of the studies employed radioimmunoassays (n = 5) followed by chemiluminescence (n = 4) and just one study employed high performance/pressure liquid chromatography (HPLC). Basal vitamin D levels varied from 17 to 43 ng/mL in the studies selected, and most of the HCV infected individuals had genotype 1 (1068/1575) with mean viral load varying from log 4.5-5.9 UI/mL. With regard to HCV treatment, most of the studies (n = 8) included HCV individuals without previous treatment, where the pooled SVR rate was 46.4%. High rates of SVR were observed in HCV individuals with vitamin D levels above 30 ng/mL (OR = 1.57; 95%CI: 1.12-2.2) and those supplemented with vitamin D (OR = 4.59; 95%CI: 1.67-12.63) regardless of genotype.

CONCLUSION: Our results demonstrated high prevalence of vitamin D deficiency and high SVR in individuals with higher serum vitamin D levels or receiving vitamin D supplementation.

Keywords: Vitamin D, Hepatitis C, Therapy, Meta-analysis, Sustained virological response

Core tip: High vitamin D levels (above 30 ng/mL) or supplementation are associated with sustained virological response in hepatitis C virus infected individuals.

INTRODUCTION

Viral hepatitis C is a serious public health problem worldwide infecting more than 130 million individuals[1]. Treatment of hepatitis C virus (HCV) infection is usually carried out using pegylated interferon (PEG-IFN) and ribavirin (RBV) for 24 wk for HCV genotypes 2 or 3, or 48 wk for HCV genotype 1 and the main objective of HCV therapy is a sustained virologic response (SVR), defined as an undetectable serum HCV-RNA level at 24 wk after the end of therapy. Rates of SVR range from 60%-70% in chronic hepatitis C (CHC) patients with genotypes 2 and 3, but is less than 50% in patients with genotype 1 using conventional therapy[2].

Recently, studies were conducted to analyze the influence of genetic and metabolic factors in antiviral response[3-5], and a recent review showed that vitamin D levels can influence HCV treatment[6]. Vitamin D itself is considered biologically inactive and is hydroxylated to 25-hydroxyvitamin D [25(OH)D] in the liver. 25(OH)D is the main circulating vitamin D metabolite and is used for classification of the vitamin D status[7,8]. In the kidney, 25(OH)D is converted to 1,25-dihydroxyvitamin D [1,25(OH)D] by 1-alpha-hydroxylase, however, it has been demonstrated that this conversion can occur in many extra-renal tissues including the liver[7,9]. Finally, 25(OH)D or 1,25(OH)2D bind to the ubiquitously expressed vitamin D receptor (VDR), which regulates approximately 3% of the human genome[10]. In this context, vitamin D deficiency has been associated with an increased risk of cancer[7,11], cardiovascular[12,13], autoimmune[14,15] and infectious diseases[6,16].

Due to these facts, there is great research interest in the role of vitamin D status in various infectious diseases. Some studies have shown that high levels of serum vitamin D level are an independent predictor of SVR following anti-viral therapy, and higher SVR is achieved with vitamin D supplementation in CHC individuals[17-22]. However, Lange et al[18] found that vitamin D deficiency was associated with a lower SVR rate only in CHC genotype 2/3 patients (treated with PEG-IFN and RBV for 24 wk), but not in CHC genotype 1 patients. Moreover, Jazwinski et al[23] found no association between vitamin D levels and SVR in 82 African American genotype 1 CHC-naïve patients, treated with PEG-IFN and RBV.

As vitamin D has an uncertain clinical value in HCV infected individuals and taking into consideration the limitations of previous reviews, we conducted an updated systematic review and meta-analysis to comprehensively assess vitamin D deficiency regarding antiviral therapy and the influence of vitamin D supplementation on SVR.

MATERIALS AND METHODS

Identification of studies

A broad search string was used in MEDLINE in order to identify relevant studies (all languages, all available years, search last completed 31.03.12) using the following search terms: [(“vitamin D” [MeSH Terms] or “vitamin D” [All Fields] or “ergocalciferols” [MeSH Terms] or “ergocalciferols” [All Fields]) or (“calcifediol” [MeSH Terms] or “calcifediol” [All Fields] or “calcidiol” [All Fields]) or (“25(OH)D” [All Fields] or “25(OH)D2” [All Fields] or “25(OH)D3” [All Fields]) and [(“HCV” [MeSH Terms]) or (“HCV” [All Fields] or “Hepacivirus” [All Fields]) or “Hepacivirus” [MeSH Terms])]. Abstracts from the European and American Association Congress of Hepatology (EASL 2011 and AASLD 2011) were also included in order to give more data on this theme.

Potentially relevant papers were accessed in order to review the abstract and/or full text. Only fully published articles were considered. Duplicate publications were deleted. Two researchers independently performed the literature search and data abstraction with regard to the inclusion and exclusion criteria by reading titles and abstracts. When reading titles and abstracts did not allow identification of eligible studies, articles were read in full. Only original studies conducted in humans were considered for the review. Thus, reviews and letters to the editor were excluded in the analysis, but read in full to identify potential relevant original studies. Disagreements between the two observers were resolved by discussion.

The following data were extracted: year of publication, number of patients, age, vitamin D levels, SVR percentage, method of measurement of vitamin D, HCV genotype, HCV viral load, percentage of naive patients. When such data were not explicitly reported, they were derived from data provided in the articles or requested from the authors through personal contacts, wherever possible.

Eligibility criteria

The study must provide information on SVR against HCV and the levels of 25(OH)D3 and/or 25(OH)D2 [henceforth referred to as 25(OH)D] in sera samples from HCV infected individuals. The inclusion criteria were: clinical studies that included HCV infected patients aged older than 18 years regardless of HCV genotype or ethnic group; provided information on SVR rates; and were reported in the English language as full papers. Studies were excluded if they met the following criteria: they did not provide information on 25(OH)D level, HCV status and/or SVR; basic studies; letters ⁄ case reports, or articles not reporting outcomes of interest or primary data (editorials, reviews).

Statistical analysis

Data were extracted from each paper and compiled for hypovitaminosis D and HCV antiviral response. Statistical analysis was performed using the Meta-Disc software 1.4[24], considering: (1) a summary of data from individual studies; (2) an investigation of the homogeneity of the studies both graphically and statistically; (3) calculation of clustered indices; and (4) exploration of heterogeneity. The meta-analysis was performed using the random-effect model by the Der Simonian and Laird method. Heterogeneity was tested for each planned analysis using the Cochran-Q heterogeneity test and measured using χ2 and I2 tests, and statistical significance was considered to be present when P < 0.05.

RESULTS

Description of studies included in the meta-analysis

A flow diagram of the search process is shown in Figure 1. The total search yielded 61 articles and 15 abstracts, after accessing the title and abstract, 65 studies were excluded for the following reasons: 49 did not provide data on vitamin D level, HCV status and/or SVR; 5 were basic studies; 8 were reviews, letters or editorials; 3 were duplicate studies.

WJG-19-5917-g001

Figure 1 Prisma flowchart for the selection of publications for the systematic review and meta-analysis. HCV: Hepatitis C virus; 25(OH)D: 25-hydroxyvitamin D.

Eleven studies involving 1575 individuals were included in this study[17,18,20-23,25-29]. The main characteristics of these studies are shown in Tables 1 and 2. Most of the studies were conducted in Europe and only one in North America. Eight studies evaluated vitamin D levels before and after antiviral therapy[17,18,21-23,25,28,29], while three were interventional studies where vitamin D supplementation was conducted[20,26,27]. Most of the studies included mono-infected HCV individuals with the mean age ranging from 38 to 56 years. Four studies were conducted in human immunodeficiency virus/HCV infected individuals[22,25,28,29]. With regard to vitamin D measurement, most of the studies employed radioimmunoassays (n = 5) followed by chemiluminescence (n = 4) and just one study employed HPLC. Basal vitamin D levels varied from 17 to 43 ng/mL in the studies selected, and most of the HCV infected individuals had genotype 1 (1068/1575) with mean viral load ranging from log 4.5-5.9 UI/mL. With regard to HCV treatment, most of the studies (n = 8) included HCV individuals without previous treatment, where the pooled SVR rate was 46.4%.

table-icon

Table 1 Summary of the general characteristics of the included studies regarding vitamin D and hepatitis C virus (mean ± SD)

table-icon

Table 2 Summary of included studies regarding vitamin D and hepatitis C virus aspects

WJG-19-5917-g002

Figure 2 Meta-analysis of 8 observational studies regarding vitamin D levels and sustained virological response against hepatitis C virus infection.

Vitamin D levels and sustained virological response

Different cut-off values for vitamin D were employed and in order to reduce this heterogeneity, a value of 30 ng/mL was used as the cut-off value, as most of the studies used this value to define vitamin D. Among the observational studies, a total of 1411 individuals were included. Using 30 ng/mL as cut-off value, the χ2 test of heterogeneity was high (P = 0.3799). There was a significant difference regarding vitamin D levels and SVR, where individuals with values higher than 30 ng/mL had a higher level of SVR. Using the random effects model by the Der Simonian and Laird method, the odds ratio was 1.57 (95%CI: 1.12-2.2) regardless of genotype (Figure 2).

A total of 1117 HCV infected individuals had low vitamin D levels (cut-off value of 30 ng/mL) representing 71% of the population studied, and most of these individuals were in the interventional studies (79.3%) as compared with the observational studies (69.9%). The highest association between vitamin D levels and SVR was observed in the study by Petta et al[17] as demonstrated by the OR and CI (OR = 1.96; 95%CI: 1.02-3.79).

Vitamin D supplementation and sustained virological response

With regard to vitamin D supplementation in HCV infected individuals in the interventional studies, the pooled estimation from 3 different studies indicated that SVR rates were higher in treated HCV individuals compared with non-treated HCV individuals. In the meta-analysis of SVR in the interventional studies where the cut-off value was 30 ng/mL, the OR was 4.59 (95%CI: 1.67-12.63) regardless of genotype (Figure 3). The test of heterogeneity (Cochran-Q = 2.86; df = 2; P = 0.2395), inconsistency I2 = 30%, and t = 0.2454. Of these studies, the OR values were higher in the study where only genotype 1 HCV individuals were included[27] (8.68) compared to the other 2 studies, one study included genotypes 1 and non-1[20] (1.90) and the other study recruited genotype 2 and 3 HCV infected individuals (5.78)[26].

WJG-19-5917-g003

Figure 3 Meta-analysis of 3 interventional studies regarding vitamin D levels and sustained virological response against hepatitis C virus infection.

Quality of the studies

Low heterogeneity was observed in the studies included in this meta-analysis according to the Q value for the observational (7.49) and interventional studies (2.86). The possible sources of heterogeneity across the studies were also explored using meta-regression analysis with the following co-variates as predictor variables: HCV genotype (1 and non-1); previous treatment (yes or no); Origin (Europe or America); method of vitamin D determination (HPLC, chemiluminescence or radiomunoassay). None of these variables interfered with the levels of vitamin D according SVR (data not shown). It is likely that this occurred because most of the studies were from Europe, including HCV genotype I individuals without previous treatment.

Although low heterogeneity was found, it was not possible to ensure high quality of all studies included in this meta-analysis. Some studies did not provide relevant data such as, mean age of the population included[23,28], mean basal vitamin D measurement[20,23,28], or mean HCV viral load[23,26-28].

DISCUSSION

Our review and meta-analysis summarize the results of eleven studies, which included a total of 1575 cases with hepatitis C, where basal 25(OH)D levels and 25(OH)D supplementation were associated with SVR in HCV patients. This updated review confirms and extends earlier results of a systematic review conducted by Cholangitis[6], who reported that vitamin D deficiency is very frequent before liver transplantation and ranges between 51% and 92%, whereas, in the liver transplantation setting, the prevalence of vitamin D deficiency is also high.

Vitamin D is metabolized by the liver and converted to 1,25-dihydroxyvitamin D3, which is the active form of the vitamin[29,30]. Individuals with chronic liver disease may have poor conversion from vitamin D3 or any of its other biologically active metabolites[31]. Severe liver disease may increase the risk of vitamin D deficiency and/or there might be a relationship between vitamin D deficiency and fibrosis. Putz-Bankuti et al[32] and Baur et al[33] also showed that low levels of 25(OH)D are associated with fibrosis and suggested that low 25(OH)D levels may predict hepatic decompensation and mortality in patients with chronic liver failure. More recently, Gal-Tanamy et al[34] showed that vitamin D3 increased the expression of the VDR and inhibited viral replication in cell culture.

Due to the observation of vitamin D deficiency in chronic liver disease patients, some studies have been conducted to evaluate vitamin D supplementation in these patients[20,26,27]. In some of these studies, it is reported that higher sunlight exposure or vitamin D supplementation should be recommended in patients with CHC[20,26,27]. In the present meta-analysis, vitamin D supplementation was related to higher SVR rates in HCV infected individuals, where the highest level was observed among genotype 1 HCV infected individuals. Although only a few studies regarding vitamin D supplementation fulfilled the eligibility criteria, different patterns were observed. The first study included only genotypes 2 and 3, the second included only genotype 1 and the third study involved genotypes 1, 2 and 3. Moreover, two of these studies were prospective and one was retrospective. Some limitations of these studies included the small number of patients, lack of vitamin D level assessment during therapy in the treatment and control groups, the design of prospective and randomized studies which were not placebo-controlled in one study[27], and the retrospective design of the study where immunocompromised HCV patients were supplemented with low-dose vitamin D (800 IU/d) after liver transplantation and most of the HCV patients (75%) had low vitamin D levels despite treatment[20].

In this meta-analysis, the levels of vitamin D were also associated with SVR, although different methods of vitamin D determination were used. Lai et al[8] demonstrated bias and variability in 25(OH)D measurements between laboratories and between different assays [quimioluminescence and liquid chromatography-tandem mass spectrometry (LC-MS/MS)] which can significantly affect clinical decision-making. In this situation, the adoption of common standards to allow assay calibration is urgently required.

Our study is the first meta-analysis of serum 25(OH)D levels and HCV infection in observational and interventional studies. Given the very small numbers of studies available to date, additional studies, ideally from different countries and populations are needed to assess potential differences in the associations between 25(OH)D and SVR for HCV. Large differences can be observed in different populations, depending on exposure to sunlight or vitamin D supplementation, and genetic differences[23]. Moreover, patients of African and Hispanic descent are less likely to respond to standard therapy[23] probably due to polymorphisms of the interleukin (IL)-28B gene, polymorphism of the VDR or vitamin D deficiency[17,35,36]. In this meta-analysis, all the individuals were Caucasian and most lived in Europe, which could explain vitamin D deficiency in this population resulting from possible low exposure to sunlight.

Meta-analysis is an important tool for revealing trends that may not be apparent in a single study. Pooling of independent, but similar studies increases precision and therefore the confidence level of the findings. A particular strength of our study is the application of advanced statistical techniques which allowed a summary of adjusted associations across studies and over the entire range of serum 25(OH)D values, despite the very heterogeneous categorization of 25(OH)D levels in the individual studies. Our study also has important limitations. First, as data on serum 25(OH)D in individuals were not available in each study, median, midpoints and mean of the groups were used for pooling. As a result, estimates of risk may have been less accurate than if data points on each individual had been used. Second, our meta-analysis was limited by the data provided in the individual studies, and although the authors tried to obtain the raw data from the articles, not all were available. Finally, although our review searched the MEDLINE database, recent Congress of Hepatology and Gastroenterology articles, and extensive checks for completeness by cross-referencing were employed, we cannot exclude the possibility that relevant studies may have been missed.

Despite its limitations, our review and meta-analysis support previous suggestions and provide the most comprehensive empirical evidence to date that basal serum 25(OH)D levels and vitamin D supplementation improves SVR in HCV infected individuals. However, available data are still sparse and in-depth analyses of these associations, in the context of additional longitudinal and prospective studies, are highly desirable to enable more precise estimates and a better understanding of the role of vitamin D in HCV infection.

ACKNOWLEDGMENTS

The authors would like to thank Christian Lange, Raymond T Chung, Assy Nimer, Andrea Branch, Eric Trépo, Mattias Mandorferk, Kian Bichoupan, Markus Peck, Alison Jazwinski, Laura Milazzo, and Salvatore Petta who kindly answered questions regarding their manuscripts in order to provide more information for this meta-analysis.

COMMENTS

Background

Hepatitis C virus (HCV) is a serious public health problem worldwide infecting more than 130 million individuals. Recently, studies have been conducted to analyze the influence of genetic and metabolic factors on antiviral response, and a recent review showed that vitamin D levels can influence HCV treatment.

Research frontiers

Vitamin D itself is considered biologically inactive and is hydroxylated to 25-hydroxyvitamin D [25(OH)D] in the liver. Some studies have suggested that vitamin D deficiency is associated with an increased risk of cancer, cardiovascular, autoimmune and infectious diseases. However, due to the limitations of previous reviews, the authors conducted an updated systematic review and meta-analysis to comprehensively assess vitamin D deficiency with regard to antiviral therapy and the influence of vitamin D supplementation on sustained virological response.

Innovations and breakthroughs

Previous individual studies demonstrated that high levels of vitamin D (above 30 ng/mL) or supplementation are associated to sustained virological response (SVR) in HCV infected individuals. In the present study, a meta-analysis of observational and interventional studies was conducted which proved that high levels of vitamin D (above 30 ng/mL) or supplementation are associated with SVR in HCV infected individuals.

Applications

By showing that basal vitamin D levels or suplementation are important for high rates of SVR in HCV patients, this study may provide a future strategy for therapeutic intervention in the treatment of HCV patients.

Terminology

HCV is an infection caused by a virus transmitted by the parenteral route. Vitamin D itself is considered biologically inactive and is hydroxylated to 25(OH)D in the liver. In the kidney, 25(OH)D is converted to 1,25(OH)2D by 1-alpha-hydroxylase, however, it has been demonstrated that this conversion can occur in many extra-renal tissues including the liver. Finally, 25(OH)D or 1,25(OH)2D bind to the ubiquitously expressed vitamin D receptor, which regulates approximately 3% of the human genome.

Peer review

The authors examined the influence of vitamin D levels or supplementation among HCV infected individuals. It was observed that high levels of vitamin D or supplementation are strongly associated to SVR among HCV infected individuals. The results are interesting and may represent the role of metabolic factors in HCV infection.

Footnotes

Supported by Coordination of Improvement of Higher Education Personnel in part

P- Reviewers Cuevas-Covarrubias SA, Kent L S- Editor Zhai HH L- Editor Webster JR E- Editor Ma S

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18. Lange CM, Bojunga J, Ramos-Lopez E, von Wagner M, Hassler A, Vermehren J, Herrmann E, Badenhoop K, Zeuzem S, Sarrazin C. Vitamin D deficiency and a CYP27B1-1260 promoter polymorphism are associated with chronic hepatitis C and poor response to interferon-alfa based therapy. J Hepatol. 2011;54:887-893. [PubMed] [DOI]

19. Nseir W, Gali M, Mouch SA, Djibre A, Nassar F, Assy N. Baseline serum HDL and vitamin D levels are strongly associated with SVR in chronic hepatitis C naïve genotype 1 patients. J Hepatol. 2011;54:S450.

20. Bitetto D, Fabris C, Fornasiere E, Pipan C, Fumolo E, Cussigh A, Bignulin S, Cmet S, Fontanini E, Falleti E. Vitamin D supplementation improves response to antiviral treatment for recurrent hepatitis C. Transpl Int. 2011;24:43-50. [PubMed] [DOI]

21.  Bitetto D, Fattovich G, Fabris C, Ceriani E, Falleti E, Fornasiere E, Pasino M, Ieluzzi D, Cussigh A, Cmet S. Complementary role of vitamin D deficiency and the interleukin-28B rs12979860 C/T polymorphism in predicting antiviral response in chronic hepatitis C. Hepatology. 2011;53:1118-1126. [PubMed] [DOI]

22. Terrier B, Carrat F, Geri G, Pol S, Piroth L, Halfon P, Poynard T, Souberbielle JC, Cacoub P. Low 25-OH vitamin D serum levels correlate with severe fibrosis in HIV-HCV co-infected patients with chronic hepatitis. J Hepatol. 2011;55:756-761. [PubMed] [DOI]

23. Jazwinski A, Clark PJ, Tillmann HL, Muir AJ. Vitamin D and treatment response in African American patients with HCV genotype 1. Hepatology. 2011;54:853.

24. Zamora J, Abraira V, Muriel A, Khan K, Coomarasamy A. Meta-DiSc: a software for meta-analysis of test accuracy data. BMC Med Res Methodol. 2006;6:31. [PubMed]

25. Milazzo L, Mazzali C, Bestetti G, Longhi E, Foschi A, Viola A, Vago T, Galli M, Parravicini C, Antinori S. Liver-related factors associated with low vitamin D levels in HIV and HIV/HCV coinfected patients and comparison to general population. Curr HIV Res. 2011;9:186-193. [PubMed]

26. Nimer A, Mouch A. Vitamin D improves viral response in hepatitis C genotype 2-3 naïve patients. World J Gastroenterol. 2012;18:800-805. [PubMed] [DOI]

27. Abu-Mouch S, Fireman Z, Jarchovsky J, Zeina AR, Assy N. Vitamin D supplementation improves sustained virologic response in chronic hepatitis C (genotype 1)-naïve patients. World J Gastroenterol. 2011;17:5184-5190. [PubMed] [DOI]

28. Soumekh A, Bichoupan K, Constable C, Benedict P, Vachon MLC, Fiel MI, Brau N, Rodriguez-Torres M, Sterling RK, Talal A. Two novel findings about interferon/ribavirin treatment: serum calcium falls and 25-hydroxyvitamin D increases. Hepatology. 2011;54:856.

29. Reiberg T, Payer BA, Obermayer-Pietsch B, Rieger A, Peck-Radosavljevic M. 1,25-OH-vitamin D levels are associated with early viral kinetics and sustained virologic response in patients with HCV-HIV coinfection. Hepatology. 2011;54:1191-1192.

30. DeLuca HF. Overview of general physiologic features and functions of vitamin D. Am J Clin Nutr. 2004;80:1689S-1696S. [PubMed]

31. Arteh J, Narra S, Nair S. Prevalence of vitamin D deficiency in chronic liver disease. Dig Dis Sci. 2010;55:2624-2628. [PubMed] [DOI]

32. Putz-Bankuti C, Pilz S, Stojakovic T, Scharnagl H, Pieber TR, Trauner M, Obermayer-Pietsch B, Stauber RE. Association of 25-hydroxyvitamin D levels with liver dysfunction and mortality in chronic liver disease. Liver Int. 2012;32:845-851. [PubMed] [DOI]

33. Baur K, Mertens JC, Schmitt J, Iwata R, Stieger B, Eloranta JJ, Frei P, Stickel F, Dill MT, Seifert B. Combined effect of 25-OH vitamin D plasma levels and genetic vitamin D receptor (NR 1I1) variants on fibrosis progression rate in HCV patients. Liver Int. 2012;32:635-643. [PubMed] [DOI]

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36. Ge D, Fellay J, Thompson AJ, Simon JS, Shianna KV, Urban TJ, Heinzen EL, Qiu P, Bertelsen AH, Muir AJ. Genetic variation in IL28B predicts hepatitis C treatment-induced viral clearance. Nature. 2009;461:399-401. [PubMed] [DOI]

Source

Government shutdown would likely roil FDA's drug-approval process

Provided by FierceBiotech

September 24, 2013 | By John Carroll

So what happens at the FDA in the event of a government shutdown next Tuesday? For now, the agency isn't saying, referring reporters to an OMB statement guiding government agencies to prepare to execute "an orderly shutdown."

But the FDA has been here before and agency watchers are referring to some of the old guidelines to prepare for what may--or may not--be about to happen. For drug developers in particular, it seems clear that a government shutdown would delay PDUFA dates for any companies looking to get a near-term approval. FDA panel reviews for drugs under regulatory review are also likely to get pushed back.

A short interruption in government services would not likely have a big impact on the regulatory timelines. But all bets are off if there's a lengthy interruption, which has the potential to roil the arrival of some closely watched therapies. Gilead ($GILD), for example, is looking for an approval by early December for sofosbuvir--with the chance of an early OK for a key breakthrough therapy.

Says the OMB: "Agencies are still in the process of reviewing relevant legal requirements and updating their plans.  Determinations about specific programs are being actively reviewed as agencies undertake this process."

- here's the OMB statement

Source

Gastroenterology
Volume 145, Issue 4 , Pages 790-800.e3, October 2013

Patrick Marcellin, Curtis Cooper, Luis Balart, Dominique Larrey, Terry Box, Eric Yoshida, Eric Lawitz, Peter Buggisch, Peter Ferenci, Martin Weltman, Emily Labriola–Tompkins, Sophie Le Pogam, Isabel Nájera, Denise Thomas, Gregory Hooper, Nancy S. Shulman, Ying Zhang, Mercidita T. Navarro, Chin Yin Lim, Michael Brunda, Norah A. Terrault, Ellen S. Yetzer

Received 3 January 2013; accepted 20 June 2013. published online 28 June 2013.

Abstract

Background & Aims

The combination of a hepatitis C virus (HCV) protease inhibitor, peginterferon, and ribavirin is the standard of care for patients with HCV genotype 1 infection. We report the efficacy and safety of response-guided therapy with danoprevir (a potent second-generation protease inhibitor), peginterferon alfa-2a (40 KD), and ribavirin in these patients.

Methods

Treatment-naïve patients (N = 237) were randomly assigned to groups given 12 weeks of danoprevir (300 mg every 8 hours; 600 mg every 12 hours, and 900 mg every 12 hours) or placebo plus peginterferon alfa-2a and ribavirin, followed by peginterferon alfa-2a and ribavirin. Patients given danoprevir who had an extended rapid virologic response (eRVR4−20: HCV RNA <15 IU/mL during weeks 4−20) stopped therapy at week 24; those without an eRVR4−20 continued therapy to 48 weeks. Patients who were given placebo received 48 weeks of peginterferon alfa-2a and ribavirin. The primary efficacy end point was sustained virologic response (SVR: HCV RNA <15 IU/mL after 24 weeks without treatment).

Results

Rates of SVR were higher among patients given danoprevir 300 mg (68%), 600 mg (85%), and 900 mg (76%) than placebo (42%) (95% confidence interval: 26%−59%). Seventy-nine percent of patients given danoprevir 600 mg had an eRVR4−20; among these, 96% had an SVR. Serious adverse events were reported in 7% to 8% of patients given danoprevir and 19% given placebo. Four patients given danoprevir (1 patient in the 600-mg group and 3 in the 900-mg group) had reversible, grade 4 increases in alanine aminotransferase, which led to early discontinuation of the 900-mg arm of the study.

Conclusions

The combination of danoprevir, peginterferon alfa-2a, and ribavirin leads to high rates of SVR in patients with HCV genotype 1 infection, but high doses of danoprevir can lead to grade 4 increases in alanine aminotransferase. Studies of lower doses of danoprevir with ritonavir, to reduce overall danoprevir exposure while maintaining potent antiviral activity, are underway; Clinicaltrials.gov number, NCT00963885.

Keywords: Danoprevir (RG7227), Hepatitis C Virus, Sustained Virologic Response, Response-Guided Therapy

Abbreviations used in this paper: ALT, alanine aminotransferase, BMI, body mass index, CI, confidence interval, eRVR, extended rapid virologic response, HCV, hepatitis C virus, PI, protease inhibitor, SVR, sustained virologic response

Conflicts of interest The authors disclose the following: P. Marcellin is an investigator for Roche, Gilead, BMS, Vertex, Novartis, Janssen-Tibotec, MSD, AbbVie, Boehringer Ingelheim, Pfizer, Alios BioPharma; received grant/research support from Roche, Gilead, BMS, Novartis, Janssen-Tibotec, MSD, Alios BioPharma; and is a speaker and expert for Roche, Gilead, BMS, Vertex, Novartis, Janssen-Tibotec, MSD, AbbVie. C. Cooper is a speaker/advisor for BMS, Merck, Roche, Vertex; an advisor for BI; and received research funding from Merck, Roche. L. Balart is on advisory committees or review panels for Genentech, Janssen, AbbVie; received grant/research support from Merck, Roche/Genentech, Bayer, Hyperion, AbbVie, Takeda, GI Dynamics, Gilead, BMS, Eisai, Vertex; and does speaking and teaching for Merck. D. Larrey D is on advisory boards for Roche, Boehringer-Ingelheim, Bristol-Myers Squibb, Janssen, MSD, AbbVie and received research grants from Roche, Boehringer-Ingelheim, Bristol-Myers Squibb, Gilead, AbbVie. T. Box is on advisory committees or review panels for Genentech, Vertex, Kadmon, Gilead; received grant/research support from Genentech, Merck, AbbVie, Idenix, Gilead, Boehringer ingelheim, BMS, Salix, Sundise, Genfit; and did speaking and teaching for Genentech, Vertex, Salix. E. Yoshida received honoraria from Roche, Merck, Vertex, Gilead, Bayer; received grant/research support from Roche, Merck, Vertex, Gilead, Pfizer, Boerhinger Ingelheim, Janssen, Astellas, AbbVie, Novartis. E. Lawitz received grant/research support from Abbvie, BMS, Gilead, GSK, Medtronic, Idenix, Merck, Novartis, Roche, Pfizer, Vertex, Tibotec/Johnson and Johnson, Achillion, Boehringer Ingelheim, Santaris, Genentech. P. Buggisch does speaking and teaching for MSD, Roche, Gilead, Novartis, Janssen, BMS. P. Ferenci is on the global advisory board for Roche/Genentech, Merck, Janssen, Boehringer-Ingelheim and Rottapharm-Madaus; is an advisor for GSK, Achillion, Idenix; on the speaker's bureau for Roche, MSD Austria, Janssen Austria, BMS Austria; received an unrestricted research grant from Roche Austria and MSD Austria. M. Weltman is on the advisory committees or review panels for Roche, Janssen, MSD, Abbvie, Gilead; and does speaking and teaching for Roche, BMS, MSD, Janssen. E. Labriola-Tompkins, S. Le Pogam, I. Nájera, and M. Brunda are employees of Hoffmann-La Roche Inc. D. Thomas and G Hooper are employees of Roche Products Ltd. N. S. Shulman, M. T. Navarro, C. Y. Lim, and E. S. Yetzer are employees of Genentech. Y. Zhang was an employee of Genentech at the time that the study was conducted. N. A. Terrault does consulting for Roche/Genentech; and received grant/research support from Roche/Genentech.

Funding This research was funded by F. Hoffmann-La Roche Ltd. Support for third-party writing assistance for this manuscript was provided by F. Hoffmann-La Roche Ltd.

PII: S0016-5085(13)00995-5

doi:10.1053/j.gastro.2013.06.051

© 2013 AGA Institute. Published by Elsevier Inc. All rights reserved.

Source

[Posted 09/25/2013]

AUDIENCE: Oncology, Pharmacy, Rheumatology, Patient

ISSUE: FDA approved changes to the prescribing information of the immune-suppressing and anti-cancer drugs Arzerra (ofatumumab) and Rituxan (rituximab) to add new Boxed Warning information about the risk of reactivation of hepatitis B virus (HBV) infection. The revised labels also will include additional recommendations for screening, monitoring, and managing patients on these drugs to decrease this risk.

In patients with prior HBV infection, HBV reactivation may occur when the body’s immune system is impaired. HBV reactivation has occurred in patients with prior HBV exposure who are later treated with drugs classified as CD20-directed cytolytic antibodies, including Arzerra (ofatumumab) and Rituxan (rituximab). Some cases have resulted in fulminant hepatitis, hepatic failure, and death.

See the FDA Drug Safety Communication1 for additional information, including a Data Summary.

BACKGROUND: Arzerra is used to treat chronic lymphocytic leukemia (CLL) in patients who have further disease after treatment with the anti-cancer drugs fludarabine and alemtuzumab. Rituxan is used to treat non-Hodgkin’s lymphoma and CLL. It is also used to treat other medical conditions, including rheumatoid arthritis, granulomatosis with polyangiitis, and microscopic polyangiitis.

RECOMMENDATIONS: To decrease the risk of HBV reactivation, FDA recommends that health care professionals:

  • Screen all patients for HBV infection before starting treatment with Arzerra or Rituxan by measuring hepatitis B surface antigen (HBsAg) and hepatitis B core antibody (anti-HBc).
  • Consult with hepatitis experts regarding monitoring and use of HBV antiviral therapy when screening identifies patients at risk of HBV reactivation due to evidence of prior HBV infection.
  • Monitor patients with evidence of prior HBV infection for clinical and laboratory signs of hepatitis B or HBV reactivation during Arzerra or Rituxan therapy and for several months thereafter, since reactivations have occurred several months following completion of therapy with these drugs.
  • In patients who develop reactivation of HBV while on Arzerra or Rituxan, immediately discontinue the drug and start appropriate treatment for HBV. Also discontinue any chemotherapy the patient is receiving until the HBV infection is controlled or resolved.  Because of insufficient data, no recommendation can be made regarding the resumption of Arzerra or Rituxan in patients who develop HBV reactivation hepatitis.

For Patients:

  • Before receiving Arzerra or Rituxan, tell your health care professional if you have or have had any severe infections, including HBV.
  • If you have had HBV infection, your health care professional should monitor you for HBV infection during treatment and for several months after you stop treatment with Arzerra or Rituxan.

Healthcare professionals and patients are encouraged to report adverse events or side effects related to the use of these products to the FDA's MedWatch Safety Information and Adverse Event Reporting Program:

  • Complete and submit the report Online: www.fda.gov/MedWatch/report.htm2
  • Download form3 or call 1-800-332-1088 to request a reporting form, then complete and return to the address on the pre-addressed form, or submit by fax to 1-800-FDA-0178

[09/25/2013 - Drug Safety Communication4 - FDA]

Page Last Updated: 09/25/2013
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Hepatitis C: A mouse at the end of the tunnel

Journal home > Advance online publication > 24 September 2013 > Full text

Research Highlight

Cell Research advance online publication 24 September 2013; doi: 10.1038/cr.2013.132

Marco Binder1 and Ralf Bartenschlager1

1Department of Infectious Diseases, Molecular Virology, University of Heidelberg, INF 345, D-69120 Heidelberg, Germany

Correspondence: Ralf Bartenschlager, E-mail: Ralf.Bartenschlager@med.uni-heidelberg.de

Since its discovery in 1989, researchers strive after a small animal model for Hepatitis C virus infection, so far with very limited success. A study recently published in Nature now for the first time reports the recapitulation of the complete life cycle of this virus in inbred mice with a functional adaptive immune system.

Worldwide, over 130 million people are chronically infected with Hepatitis C virus (HCV). Acute infection goes along with mild and generalized symptoms, and therefore mostly remains undiagnosed; in more than half of the patients, however, the infection persists and, over the years, can cause liver damage such as fibrosis, cirrhosis or hepatocellular carcinoma.

HCV is a positive strand RNA virus of the family Flaviviridae. Studies of this virus have made huge leaps forward since the implementation of efficient cell culture systems1,2; nonetheless, our knowledge of HCV-associated pathogenesis is scarce owing to the lack of a practicable animal model. So far, chimpanzees are the only animals fully susceptible to HCV infection; however, legal, ethical, economical let alone practical reasons dictate the establishment of small animal models as an alternative. Most efforts have been put into various mouse models3, but in general, mice are resistant to HCV infection. Only individual steps of the lifecycle could be reproduced in mouse cells: expression of human variants of the entry receptors CD81 and occludin mediates virus uptake into mouse cells4,5; selectable replicons demonstrated that HCV RNA can be replicated in mouse cells, albeit inefficiently; and assembly as well as secretion of HCV particles can be achieved in mouse hepatocytes3. In contrast, for studying the full replication cycle in living animals, systems had to be developed, in which mouse hepatic tissue was inducibly or constitutively deteriorated to allow repopulation by human hepatocytes3. This inter-species chimerism naturally required the animals to be immuno-deficient to avoid graft rejection. Nonetheless, particularly the uPA-SCID model has become very popular, especially for pre-clinical drug testing and validation and for studying passive immunization strategies against HCV infection. Still, for research on vaccine development and pathogenesis, these models are of limited to no use, as such studies require robust immune responses.

The teams of Alexander Ploss and Charles Rice now report a breakthrough on the way to an immune-competent mouse model6. They had shown previously that adenoviral expression of human CD81 and occludin in mouse liver cells rendered fully immune-competent mice susceptible to HCV infection; however, replication was abortive5. In their present study, the authors take this approach two steps further: (1) by establishing mice that express the entry factors transgenically; (2) by additionally incapacitating the innate antiviral response. It had been suggested earlier that this response severely impacts HCV replication in mouse cells7,8, and indeed, its blocking in an otherwise fully immune-competent background sufficed to increase viral replication to detectable levels in entry factor transgenic (EFT) mice. By testing knock-outs of several factors involved in innate antiviral defense, STAT1−/− EFT mice were found to be best to support HCV replication, which was sustained for up to 11 weeks, with viral genomes detectable in both liver tissue and serum. The authors could corroborate that this viremia relied on authentic viral replication, as it could be inhibited by neutralizing antibodies or an HCV-specific antiviral compound; moreover, a drastic reduction in viral replication was observed in mice that additionally carried a knock-out of the ppia (Cyclophilin A) gene, a well-known HCV host dependency factor in humans9. On the down side, one has to acknowledge that the infection rate in the liver was stunningly low with only 0.4% of hepatocytes infected at a given time. In contrast, in human livers HCV antigen has been detected in around 20% of cells on average. This low rate of infection in mice is coherent with comparatively low infectivity titers of < 100 infectious units per ml mouse serum; somewhat in contrast, however, are the high RNA titers of 104-106 copies per ml, arguing for a high excess of non-infectious RNA-containing structures. The mechanism by which they are released into the serum of infected mice and their biophysical properties remain to be determined. Regardless of the rather sparse hepatic infection, strikingly, the authors found clear evidence for the mounting of an immune response, such as splenomegaly with increased relative frequencies of NK- and B-cells as well as infiltration of infected livers by CD8+ T-cells. HCV infection was apparently cleared by the T-cell response, which at late stages of infection shifted towards a memory phenotype.

These results are remarkable and highlight the perspective of such an animal model possibly also for studies on (immune-mediated) pathogenesis and eventually development of T-cell activating vaccines. A few caveats, however, still need to be overcome on this front: none of the animals in the study developed a lasting, chronic infection, but rather cleared the virus after about 80 days; this might be resolved by adaptation of the virus to its new host by prolonged, serial passaging in mice. Additionally, the used transgenic mice lack STAT1, which is not only responsible for the immediate intrinsic antiviral response, but also required for signaling in response to all types of interferons (I, II and III). This deficiency for one deprives CD8+ T-cells of their antiviral activity through interferon-γ secretion, which has been reported to be more important in controlling HCV than direct cytolytic effects10, and, secondly, is likely to also affect the phenotypic differentiation and activation of various immune cells. One possible way to overcome the latter issue could be to use a tissue-specific knock-out of the stat1 gene, specifically targeting hepatocytes. Alternatively, a combined knock-out of different interferon effector genes with antiviral activity against HCV might still allow for HCV replication, while restoring general responsiveness to interferons.

Even with the mentioned limitations, the presented strategy denotes a milestone for HCV research and is the first system that can truly be called a small animal model for HCV infection. As it does not rely on xenografts, it is not only more practicable and much cheaper than previous models, but also more robust as it is completely independent from variations of human graft donors. Albeit still in need for optimizations, finally one can see the long-awaited HCV-susceptible mouse at the end of the tunnel.

References

1. Lohmann V, Körner F, Koch J, et al. Science 1999; 285:110–113. | Article | PubMed | ISI | CAS |

2. Wakita T, Pietschmann T, Kato T, et al. Nat Med 2005; 11:791–796. | Article | PubMed | ISI | CAS |

3. Mailly L, Robinet E, Meuleman P, et al. Front Microbiol 2013; 4:213. | Article | PubMed |

4. Ploss A, Evans MJ, Gaysinskaya VA, et al. Nature 2009; 457:882–886. | Article | PubMed | ISI | CAS |

5. Dorner M, Horwitz JA, Robbins JB, et al. Nature 2011; 474:208–211. | Article | PubMed | ISI | CAS |

6. Dorner M, Horwitz JA, Donovan BM, et al. Nature 2013 Jul 31. doi: 10.1038/nature12427 | Article |

7. Lin LT, Noyce RS, Pham TN, et al. J Virol 2010; 84:9170–9180. | Article | PubMed | ISI | CAS |

8. Chang KS, Cai Z, Zhang C, et al. J Virol 2006; 80:7364–7374. | Article | PubMed | ISI | CAS |

9. Lohmann V. Curr Top Microbiol Immunol 2013; 369:167–198. | PubMed |

10. Jo J, Aichele U, Kersting N, et al. Gastroenterology 2009; 136:1391–1401. | Article | PubMed | CAS |

Source

Journal of Hepatology
Volume 59, Issue 4 , Pages 696-700, October 2013

Giovanni Squadrito, Irene Cacciola, Angela Alibrandi, Teresa Pollicino, Giovanni Raimondo,

Received 22 August 2012; received in revised form 8 May 2013; accepted 31 May 2013. published online 10 June 2013.

See Editorial, pages 646–647

Abstract

Background & Aims

Occult hepatitis B virus infection (OBI) frequently occurs in patients with hepatitis C virus (HCV) related chronic hepatitis (CHC), but the influence of OBI on the CHC outcome is still uncertain. This observational cohort study evaluated the clinical evolution of CHC patients according to their OBI status.

Methods

From 1991 to 2000, 326 hepatitis B surface antigen negative CHC patients were tested for OBI by the analysis of liver biopsy DNA extracts. A total of 128/326 cases (39.2%) tested OBI positive and 198/326 (60.8%) OBI negative. Ninety-four of 326 patients (37 OBI positive, 57 OBI negative) were followed-up for a median time of 11years (range 5–19years). During the follow-up, 79/94 patients underwent anti-HCV treatments and 26 achieved a sustained virological response that occurred independently of their OBI status.

Results

Eighteen patients (13/37 OBI positive, 5/57 OBI negative, p<0.01) developed hepatocellular carcinoma (HCC). Among the 76 non-HCC individuals, 15 subjects (8/24 OBI positive, 7/52 OBI negative, p<0.05) developed advanced forms of cirrhosis. Eighteen patients died during follow-up and 2 underwent liver transplantation. OBI positive individuals had a cumulative survival rate significantly shorter than OBI negative individuals (p=0.003). Liver-related deaths were more frequently found in OBI positive than OBI negative patients (12/37 OBI positive vs. 6/57 OBI negative patients respectively, p<0.01). Finally, non-response to anti-HCV therapy was significantly associated with lower survival (p=0.02).

Conclusions

Among CHC patients, occult HBV co-infected individuals are a category at high risk of progression toward cirrhosis, HCC development, and lower survival.

Abbreviations: OBI, occult HBV infection, HCV, hepatitis C virus, CHC, chronic hepatitis C, SVR, sustained virological response, HCC, hepatocellular carcinoma, OLT, orthotopic liver transplantation, HBV, hepatitis B virus, HBsAg, hepatitis B surface antigen, IFNα, interferon-α, LDW, liver disease worsening

Keywords: HBsAg-negative, Liver biopsy, HBV DNA, Cirrhosis, Hepatocellular carcinoma

PII: S0168-8278(13)00376-0

doi:10.1016/j.jhep.2013.05.043

© 2013 European Association for the Study of the Liver. Published by Elsevier Inc. All rights reserved.

Source

Public release date: 18-Sep-2013
Contact: Eric Peters
petersem@vcu.edu
804-828-0563
Virginia Commonwealth University

A smartphone app can quickly screen for cognitive dysfunction often found in patients with cirrhosis, according to a new Virginia Commonwealth University study. The cognitive dysfunction, known as minimal hepatic encephalopathy (MHE), has been difficult to diagnose.

Published in the September issue of the journal Hepatology, the study tested the validity of the Stroop smartphone application – called EncephalApp_Stroop – as a method to screen for MHE.

Validation of the app as a health care tool opens the door for its use as a point-of-care (POC) instrument that providers can use to quickly, easily and confidently evaluate their patients who may be suffering from MHE.

"This app can be used to rapidly select which patients are likely to benefit from further MHE testing and potential treatment, which has been lacking at this time." said principal investigator Jasmohan Bajaj, M.D., associate professor, Department of Gastroenterology, Hepatology and Nutrition, VCU School of Medicine, who practices at VCU and McGuire VA Medical Centers. "It can be translated into practice by clinic assistants, nurses or other non-MD professionals to add a cost-effective approach to the rapid diagnosis of MHE."

MHE is associated with impaired quality of life, employment and driving capability and a higher risk of progression to overt hepatic encephalopathy, but treatment has not been standard of care in the U.S. partly because MHE testing is not feasible.

The free EncephalApp_Stroop app, which Bajaj developed, utilizes the Stroop task, which is used to evaluate psychomotor speed and cognitive flexibility through identification in various combinations of ink colors and words.

To determine the validity of the app as a health care tool, Bajaj and his team recruited 126 patients with cirrhosis, some of whom had overt hepatic encephalopathy, 51 age-balanced health controls and 43 additional patients with cirrhosis for the prospective validation cohort. They underwent a battery of recommended cognitive tests including the traditional MHE test and the Stroop app evaluation.

The team concluded that the Stroop app is a valid, reliable method for screening for MHE. Use of the app may improve the screening process by making it easier and faster and, subsequently, increase treatment rates in potential patients with MHE.

They suggest further studies evaluating the app's validity in other populations are needed.

The app can be downloaded on iTunes for iPhones or iPads and is available in Spanish, Czech, Slovak and Indonesian languages.

Source