Background: Idursulfase has limited passage through the bloodbrain barrier when administered intravenously. Objectives: We have undertaken a program to develop an intrathecal (IT) formulation of idursulfase to target CNS manifestations of MPS II. Methods: In a safety study, single bolus injections of idursulfase-IT 3 mg (n=12), 30 mg (n=6), or 100 mg (n=12) were administered via implanted drug delivery device (IDDD) once every 4 weeks to cynomolgus monkeys for 6 months. Weekly IV injections of 0.5 mg/ kg idursulfase were administered concomitantly. Device implant controls (n=6) were administered IV saline and IT PBS; vehicle controls (n=12) were administered IV and IT vehicle. In an efficacy study, idursulfase-IT was administered intrathecally to idursulfase knockout mice (n=3) once weekly for 3 weeks. Results: In monkeys, the combination of IV and IT idursulfase was not associated with any significant adverse toxicologic events compared with controls. Immunohistochemical (IHC) staining detected idursulfase-IT protein in all brain areas in the 100 mg dose group, with a deposition gradient from the cerebral cortex to the ventricular white matter. Colocalization staining revealed idursulfase-IT associated with neurons and oligodendrocytes. Additionally, idursulfase-IT appeared to be associated with axonal structures, suggestive of anterograde axonal transport. In the efficacy study in mice, morphological improvements were seen in all brain areas. A marked reduction in CNS cellular vacuolization was seen via both light and electron microscopy. IHC staining revealed a reduction in LAMP-1 (lysosomal associated membrane protein 1). Conclusions: Idursulfase-IT safely reaches relevant CNS tissues in monkeys and is efficacious in MPS II mice.

It is uncertain whether occult hepatitis B virus co-infection will hasten progressive liver disease in chronic hepatitis C patients after liver transplantation. This study evaluated fibrosis progression and severe fibrosis in 118 consecutive hepatitis B surface antigen-negative patients with virological and histological evidence of recurrent chronic hepatitis C infection co-infected with occult hepatitis B virus after liver transplantation. HBV DNA was detected from serum at the time of recurrent chronic hepatitis C infection by polymerase chain reaction. Each subject underwent a repeat liver biopsy 5 years post-liver transplantation. Occult hepatitis B virus co-infection was present in 41 of the 118 (34.7%) patients. At 5 years post-liver transplantation, 13 of the 41 occult hepatitis B virus co-infected patients compared with 16 of the 77 patients without occult hepatitis B virus co-infection developed fibrosis progression (31.7% vs. 20.8%, respectively, p = 0.39). Eight of 41 the occult hepatitis B virus co-infected patients compared with 13 of the 77 patients without occult hepatitis B virus co-infection had severe fibrosis (19.5% vs. 16.9%, respectively, p = 0.97). In conclusion, occult hepatitis B virus co-infection in patients with recurrent chronic hepatitis C infection was not associated with accelerated fibrosis progression or severe fibrosis after liver transplantation.

Occult hepatitis B virus (HBV) infection in individuals without hepatitis B surface antigen (HBsAg) can be identified in hepatitis C virus (HCV) infected patients. However, its role in fibrosis progression remains uncertain. This retrospective study compared the fibrosis progression (defined as fibrosis progression by at least one stage) and progression to severe fibrosis (fibrosis stage 3 or 4) in HCV patients with occult HBV infection. Occult HBV infection was diagnosed by the detection of HBV DNA in the serum of 74 consecutive anti-HCV positive patients by PCR. Thirty-one patients (41.9%) had occult HBV infection. All 74 patients had a median of 2 (range 2–3) liver biopsies. The median time between the first and last liver biopsy was 57.7 (range 15.0–132.8) months. Eleven of the 31 patients with occult HBV infection compared with 12 of the 43 patients without occult HBV infection had fibrosis progression (35.5% versus 27.9%, respectively, p=0.608). Six of the 31 patients with occult HBV infection compared with 8 of the 43 patients without occult HBV infection developed severe fibrosis (19.4% versus 18.6%, respectively, p=0.946). In conclusion, chronic HCV patients with occult HBV co-infection does not seem to progress more than patients without occult HBV infection. However, more large-scale studies are needed before a definite conclusion can be obtained.

Injection drug users represent the largest cohort of patients with established hepatitis C virus (HCV) infection as well as the group that is at highest risk for new infections. Most published studies have focused on the clinical consequences of established HCV infection and have not examined the consequences of new infection. The aim of the current study was to measure the virological consequences of HCV in patients with ongoing injection drug use that might pose a risk for new and/or for superinfection with additional strains of HCV. We examined the following groups: (a) those with resolved HCV infection with ongoing injection drug use, (b) those with chronic infection who continued to inject and (c) those with chronic infection who no longer injected. Our study demonstrated a spectrum of responses. The majority of patients appeared to be 'protected' from new infection. None of six patients with resolved infection had detectable HCV RNA by quantitative or qualitative PCR when followed for 1 year. Similarly, despite ongoing injection drug use, no patient with persistent infection had a 'switch' in HCV genotype indicative of possible superinfection. Virological analysis of HCV quasispecies to detect possible infection with new variants of HCV in patients with apparently 'stable' infection, indicated divergence of virus over time, divergence that was unrelated to injection drug behaviour. Thus, patients with ongoing or prior HCV infection appear to develop immunity that protects against further infection with HCV despite repeated exposure.

Liver disease in patients coinfected with HIV and hepatitis C virus (HCV) has received increasing attention in recent years. Steatosis is accepted as an important contributor to liver disease in patients with HCV, but despite coinfected patients having several reasons to have steatosis, the prevalence and significance of such changes has received scant attention. We examined steatosis in an unselected cohort of coinfected patients and compared its prevalence and predictors with findings in monoinfected patients, where these relationships have been established. We studied 92 coinfected and 372 monoinfected patients undergoing staging liver biopsy. Baseline characteristics of the two groups differed significantly, pointing at different contributors to steatosis in each. Histological inflammation and fibrosis were very similar in the two groups, but steatosis was less in coinfected patients. Steatosis had a univariate association with fibrosis in both groups, but retained a multivariate association only in monoinfected patients. Other multivariate predictors of steatosis in monoinfected patients were the accepted variables of elevated body mass index, male sex, and genotype 3a infection, as well as age. In coinfected patients, however, age was the only multivariate predictor. Undetectable HIV viral load was associated with steatosis in coinfected patients in univariate analysis, but highly active antiretroviral therapy or its individual components could not be initially linked to steatosis. In conclusion, steatosis is less common in HIV/HCV coinfected patients than similar HCV monoinfected patients, and predictors of steatosis differ between the two groups.

BACKGROUND & AIMS:Keratins 8 and 18 protect the liver from stress. Keratin 8 and 18 variants in 17 of 467 liver disease explants and 2 of 349 blood bank controls were previously reported in 5 analyzed exonic regions. We asked whether mutations were present in the remaining 10 exons of keratins 8 and 18.METHODS:Exonic regions were polymerase chain reaction-amplified from genomic DNA, isolated from the above-mentioned 2 cohorts, and analyzed for the presence of mutations. Mutant keratins were also studied biochemically.RESULTS:We identified 10 novel keratin 8 and 18 heterozygous variants in 44 of 467 explants and 11 of 349 controls: keratin 18 deletion (delta64-71), a keratin 8 frameshift that truncates the last 14 amino acids; 8 missense keratin 8 and 18 alterations; and several new polymorphisms. The most common variant, keratin 8 R340H, at the highly conserved R340 was found in 30 of 467 explants and 10 of 349 controls (P = .02) and was confirmed in the diseased livers by generation of an R340H-specific antibody. Germline transmission and variant protein expression were verified. The mutations involved a variety of liver diseases, and some variants had an ethnic background preponderance. Mutations that introduced disulfide bonds (keratin 8 G61C or R453C) decreased keratin solubility, particularly after oxidative stress, whereas others decreased keratin 8 phosphorylation (keratin 8 G433S).CONCLUSIONS:The overall frequency of keratin 8 and 18 variants was 12.4% in 467 liver disease explants and 3.7% in 349 blood bank controls (P < .0001). Variants can alter keratin solubility or phosphorylation and may render individuals susceptible to end-stage liver disease, depending on their genetic background and exposure to other insults, such as alcohol or viral infection.

Inhibition of inosine monophosphate dehydrogenase (IMPDH) is one of several proposed mechanisms of action for ribavirin (RBV), a critical component of the current treatment for chronic hepatitis C (CHC). This study was a double-blind, placebo-controlled dose-escalation study of a novel, selective, orally active small molecule inhibitor of IMPDH, merimepodib (VX-497 or MMPD) in combination with standard interferon-alpha (IFN-alpha). Fifty-four treatment-naive patients with genotype-1 CHC were randomized to receive IFN-alpha 3 MIU subcutaneously three times a week, alone or in combination with 100 mg or 300 mg (every 8 h) of MMPD for 4 weeks. At the end of 4 weeks, all patients were offered 48 weeks of treatment with IFN-alpha/RBV. The objectives of the study were to evaluate the tolerability of the IFN-alpha/MMPD combination and to evaluate whether MMPD had an on-treatment effect on HCV-RNA, similar to RBV when added to IFN-alpha. The drug combination was generally well tolerated; one patient at the higher dose discontinued because of elevated alanine aminotransferase levels. No pharmacokinetic interactions were evident between the two drugs. Analysis of covariance that adjusted for a baseline imbalance in HCV-RNA in the intent-to-treat population did not show any significant differences between the treatment groups, or between MMPD plus IFN-alpha compared with IFN-alpha alone. However, the per-protocol primary efficacy analysis based on treatment-compliant patients demonstrated a greater reduction in mean HCV-RNA in the combination of 100 mg MMPD plus IFN-alpha compared with IFN-alpha alone (-1.78 log vs -0.86 log, P=0.037). In conclusion, the addition of a selective IMPDH inhibitor to IFN-alpha was well tolerated. In a low-dose range, the addition of MMPD may have the potential to add to the antiviral efficacy of IFN-alpha. Larger, longer duration trials incorporating pegylated IFN would be required to determine whether this combination, alone or with RBV, would increase either early or sustained virological response rates.

Background/Aims: The aim of this study was to evaluate long term safety and antiviral activity of different doses of emtricitabine given once daily to patients chronically infected with hepatitis B.Methods: Eligible patients were randomized in a double-blind, parallel study to evaluate 25, 100 or 200 mg once daily doses of emtricitabine for 48 weeks. Patients were then followed for an additional 48 weeks on open-label 200 mg emtricitabine. Serum HBV DNA, ALT, and hepatitis B serology were measured at regular intervals over the 2 years. Resistance surveillance was performed after 1 and 2 years on viremic samples, i.e. > 4700 copies/mL.Results: Emtricitabine was well tolerated and produced a dose proportional antiviral response. After 2 years, 53 % of the patients had serum HBV DNA <= 4700 copies/mL, 33% seroconverted to anti-HBe and 85% had normal ALT. Eighteen percent of the patients who had received 200 mg emtricitabine for 2 years developed resistance mutations.Conclusions: Emtricitabine was well tolerated and demonstrated a potent antiviral response for up to 2 years in patients with chronic hepatitis B infection. Based on these data, 200 mg emtricitabine once daily was chosen as the optimal dose for future hepatitis B studies. (c) 2005 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.

Heavy alcohol use contributes to liver disease in the setting of chronic hepatitis C virus (HCV) infection. Whether this is true for light or moderate alcohol use has not been demonstrated. Light alcohol use has survival benefits at a population level and is practiced by most patients with chronic HCV infection. In this study, 800 patients with HCV undergoing liver biopsy at three sites had detailed alcohol histories recorded and the relationship between alcohol and hepatic fibrosis was assessed. On univariate analysis, heavy alcohol use (>50 g/day) was associated with an increase in mean fibrosis (P =.01). Such an association could not be demonstrated for light and moderate alcohol use. For each category of alcohol intake (none, light, moderate, and heavy), a spectrum of fibrosis was observed. On multivariate analysis, age, serum alanine aminotransferase (ALT), and histological inflammation were the independent predictors of fibrosis (P = <.0001,.0003, <.0001, respectively). In conclusion, heavy alcohol use exerts a greater effect on fibrosis than light or moderate use. There is a range of fibrosis at each level of alcohol use. Age, serum ALT, and inflammation are independently associated with fibrosis in multivariate analysis, highlighting the fact that variables other than alcohol intake predominate in the production of hepatic fibrosis.

Anemia and decreased health-related quality of life (HRQL) are common in patients receiving combination therapy of interferon alfa (IFN) and ribavirin (RBV) for chronic hepatitis C virus (HCV) infection. In a randomized, prospective study evaluating the effectiveness of epoetin alfa in maintaining RBV dose, alleviating anemia, and improving HRQL in anemic (Hb < or = 12 g/dL) HCV-infected patients receiving combination therapy, patients receiving epoetin alfa had significant improvements in HRQL compared with placebo. In this study, 185 patients were randomized to 40,000 units of epoetin alfa subcutaneously weekly or placebo for an 8-week double-blind phase (DBP), followed by an 8-week open-label phase during which all patients received epoetin alfa. To further assess the impact of epoetin alfa on HRQL, post hoc analyses were conducted in the same patient population to compare the HRQL of these patients at randomization with norms of other populations, and to determine the critical relationship between hemoglobin (Hb) levels and HRQL. Mean HRQL scores of anemic HCV-infected patients receiving combination therapy at randomization were significantly lower than those of both the general population and patients who had other chronic conditions. Patients receiving epoetin alfa who had the greatest Hb increases from randomization to the end of the DBP also had the largest improvements in HRQL. Hb improvement was an independent predictor of HRQL improvement in these patients. In conclusion, epoetin alfa provided clinically significant HRQL improvement in HCV-infected patients receiving IFN/RBV therapy.

Keratin 8 and 18 (K8/18) phosphorylation plays a significant and site-specific role in regulating keratin filament organization, association with binding proteins, and modulation of cell cycle progression. Keratin hyperphosphorylation correlates with exposure to a variety of stresses in cultured cells and in mouse models of liver, pancreatic, and gallbladder injury, and it is found in association with mouse and human Mallory bodies. We asked whether K8/18 phosphorylation correlates with human liver disease progression by analyzing liver explants and biopsies of patients with chronic noncirrhotic hepatitis C virus (HCV) or cirrhosis. We also examined the effect of HCV therapy with interleukin-10 on keratin phosphorylation. Using site-specific antiphosphokeratin antibodies we found keratin hyperphosphorylation on most K8/18 sites in all cirrhotic liver explants tested and in most liver biopsies from patients with chronic HCV infection. Immunofluorescence staining of precirrhotic HCV livers showed focal keratin hyperphosphorylation and limited reorganization of keratin filament networks. In cirrhotic livers, keratin hyperphosphorylation occurred preferentially in hepatic nodule cells adjacent to bridging fibrosis and associated with increased stress kinase activation and apoptosis. Histological and serological improvement after interleukin-10 therapy was accompanied by normalization of keratin hyperphosphorylation on some sites in 7 of 10 patients. In conclusion, site-specific keratin phosphorylation in liver disease is a progression marker when increased and a likely regression marker when decreased.

Lamivudine is an effective first-line therapy for chronic hepatitis B virus (HBV) infection, accomplishing the goals of viral suppression, normalization of alanine aminotransferase (ALT) levels, histological improvement, and seroconversion. In the lamivudine clinical trials, up to 32% of patients positive for hepatitis B e antigen (HBeAg) lost HBeAg after 1 year of treatment, and approximately 18% achieved HBeAg seroconversion. ALT levels greater than five times the upper limit of normal increased the likelihood of HBeAg loss. The rates of seroconversion and resistance both increase with the length of treatment. In HBeAg-negative patients, two thirds showed response after 6 to 12 months of therapy, but this response diminished over time despite continued treatment, largely due to the emergence of resistance. Resistance is present in nearly 70% of patients at 5 years. Resistance reverses prior biochemical, virological, and histological gains and can lead to progressive liver failure. Careful patient selection is important, therefore, to maximize the potential for a treatment response under limited therapy.

Background/aims: New methods to detect virus-specific T-cell responses have recently been developed. Several human leukocyte antigen (HLA)-peptide tetramers for the detection of hepatitis C virus (HCV)-specific CD8+ T cells are under evaluation. Methods: Evaluation of one HLA class I-tetramer (HCVNS3-2) for the detection of HCV NS3-specific CD8+ T cells in a series of 38 HLA-A2+ chronically infected patients. Results: Almost half (42%) of the patients had detectable NS3-specific CD8+ T cells. The frequencies of such cells ranged from 0.01% to 0.22% of total CD8+ T cells. No significant differences in clinical features or mean viral load were detected between patients with or without tetramer+CD8+ T cells. Conclusions: The tetramer HCVNS3-2 may be very useful for the study of the HCV-specific CD8+ immune response. Combination of this reagent with other tetramers based on other HCV peptides may help in the understanding of the immune response to the virus. However, a panel of tetramers based on several parts of the HCV polyprotein may be a mandatory requirement to explore the whole breadth of the CD8+ T-cell response against HCV and to detect that response in the majority of patients with chronic infection.