A 3-year follow-up study after treatment with simeprevir in combination with pegylated interferon-α and ribavirin for chronic hepatitis C virus infection.

BACKGROUND: Simeprevir is approved with pegylated interferon and ribavirin (PR) for chronic hepatitis C virus (HCV) genotype (GT) 1 and GT4 infection in the USA and the European Union. METHODS: This 3-year follow-up study assessed the durability of sustained virologic response (SVR) (undetectable HCV RNA 12 or 24 weeks after treatment end), and evaluated the persistence of treatment-emergent NS3/4A protease inhibitor resistance in patients not achieving SVR following treatment with simeprevir plus PR in the parent study. The maintenance of SVR after the last post-therapy follow-up visit of the parent study (LPVPS) was assessed using HCV RNA measurements. The persistence of treatment-emergent NS3 amino acid substitutions in patients with no SVR at LPVPS was assessed using population sequencing. No study medications were administered. RESULTS: Overall, 249 patients were enrolled (200 with SVR at LPVPS; 49 with no SVR at LPVPS); 40 patients discontinued prematurely (18 with SVR; 22 with no SVR). All 200 enrolled patients who achieved SVR in the parent study maintained SVR until the last available visit in this study (median follow-up time: 35.8 months). The treatment-emergent NS3 amino acid substitutions detected at time of failure in the parent study in 43/49 enrolled patients were no longer detected in 37/43 (86.0%) at the end of this study (median follow-up time: 179.9 weeks [41.3 months]). CONCLUSION: This 3-year follow-up study provides evidence for the long-term durability of SVR (100%) after successful treatment with simeprevir plus PR. Treatment-emergent NS3 amino acid substitutions became undetectable in the majority of patients. TRIAL REGISTRATION: NCT01349465; ClinicalTrials.gov .

Clinical impact of pharmacokinetic interactions between the HCV protease inhibitor simeprevir and frequently used concomitant medications.

AIMS: Direct-acting antiviral agents (DAAs) for the treatment of hepatitis C (HCV) can be associated with drug-drug interactions (DDIs) with concomitant medications. The practical clinical implications of such DDIs are poorly understood. We assessed the clinical impact of possible pharmacokinetic (PK) interactions between simeprevir and frequently prescribed concomitant medications. METHODS: This post hoc analysis pooled data from nine studies which evaluated simeprevir (SMV)-based interferon-free HCV treatment. Three classes of frequently used concomitant medications of interest (CMOIs) were analysed [antihypertensive drugs (AHDs), anxiolytic drugs (AXDs) and lipid-lowering drugs (LLDs)] and categorized as amber or green according to their DDI potential with SMV (green: no DDIs; amber: potential/known PK interactions). Concomitant medications not recommended to be coadministered with SMV were not included. The composite primary endpoint was defined as the frequency of either discontinuation, interruption or dose modification of the CMOI during 12 weeks of SMV treatment. RESULTS: Few patients met the composite endpoint in the various subgroups. Patients on amber CMOIs tended to experience CMOI modification more often (13.4-19.4%) than those on green CMOIs (3.1-10.8%). There was no difference in the frequency of adverse events between patients taking green and those taking amber CMOIs. CONCLUSIONS: In this large pooled analysis, coadministration of the evaluated commonly prescribed medications with known or potential PK interactions with SMV was manageable and resulted in few adjustments of concomitant medications. Our method could serve as a blueprint for the evaluation of the impact of DDIs.

Simeprevir with peginterferon α-2a/ribavirin for chronic hepatitis C virus genotype 1 infection in treatment-experienced patients: an open-label, rollover study.

BACKGROUND: This Phase 3, open-label, rollover study (NCT01323244) investigated the efficacy and safety of simeprevir plus peginterferon α-2a (PegIFNα-2a) and ribavirin (RBV) in a well-characterized population of HCV genotype 1 (GT1)-infected treatment-experienced patients. METHODS: Patients who had failed PegIFNα/RBV treatment in the placebo arm of a previous Phase 2/3 simeprevir study (Phase 2/3 group, n = 125), or had been exposed to HCV direct-acting antivirals (simeprevir or other) for up to 14 days in a selected Phase 1 study (Phase 1 group, n = 16), were eligible. Phase 2/3 group patients were classified according to prior relapse, breakthrough, or non-response (null response, partial response, non-classifiable non-response) to PegIFNα/RBV. Eight patients in the Phase 1 group received short-term (≤14 days) simeprevir. Treatment comprised simeprevir 150 mg once daily (QD) plus PegIFNα-2a/RBV for 12 weeks followed by PegIFNα-2a/RBV for 12 or 36 weeks (using response-guided therapy [RGT] to determine total treatment duration in Phase 2/3 prior relapsers or breakthrough) or 36 weeks fixed (Phase 2/3 group non-responders and Phase 1 group). The primary endpoint was sustained virologic response 12 weeks after planned end of treatment (SVR12). RESULTS: Phase 2/3 group: SVR12 rate was 69.6% (87/125) overall; 92.7% (51/55), 60.0% (6/10), 64.3% (18/28), and 36.7% (11/30) in patients with prior relapse, viral breakthrough, partial response, or null response, respectively. SVR12 rates were similar for patients with HCV GT1a (66.0% [33/50]) and GT1b infection (72.0% [54/75]) and among HCV GT1a-infected patients with/without a baseline Q80K polymorphism (66.7% [8/12] and 65.8% [25/38], respectively). The majority of RGT-eligible patients (prior viral relapse or breakthrough) met RGT criteria (89.2% [58/65]); of these, 89.7% (52/58) achieved SVR12. Overall, 16.0% (20/125) of patients experienced on-treatment failure and 14.4% (18/125) experienced post-treatment failure (15 relapses, 3 missing data). Phase 1 group (simeprevir-naïve and -experienced patients combined): SVR12 rate was 37.5% (6/16). Safety and tolerability findings were comparable to those of the feeder studies. CONCLUSIONS: The majority of RGT-eligible patients met criteria for shortening treatment to 24 weeks in total. Simeprevir 150 mg QD with PegIFNα-2a/RBV led to a high SVR rate among prior relapsers with HCV GT1 infection. No new safety signals were noted. TRIAL REGISTRATION: NCT01323244 . (date of registration: March 24, 2011).

Efficacy, safety, and pharmacokinetics of simeprevir, daclatasvir, and ribavirin in patients with recurrent hepatitis C virus genotype 1b infection after orthotopic liver transplantation: The Phase II SATURN study.

BACKGROUND: Recurrent hepatitis C virus (HCV) infection following liver transplantation is associated with accelerated progression to graft failure and reduced patient survival. METHODS: The Phase II, open-label SATURN study (NCT01938625) investigated the combination of simeprevir (SMV), daclatasvir (DCV), and ribavirin (RBV) administered for 24 weeks in 35 patients with recurrent HCV genotype (GT) 1b infection after orthotopic liver transplantation (OLT). RESULTS: High rates of both on-treatment and sustained virologic response 12 weeks after end of treatment (SVR12) were achieved in patients who were either treatment-naïve or had failed post-OLT treatment with peginterferon and RBV. Overall, 91% of patients (32/35) achieved SVR12. The combination was generally well tolerated, with an adverse event profile consistent with that observed in previous clinical trials of SMV or DCV separately. Co-administration of SMV with cyclosporine resulted in significantly increased SMV plasma exposures, which was not the case with the co-administration of SMV with tacrolimus. Therefore, the concomitant use of SMV with cyclosporine is not recommended. CONCLUSION: The interferon-free combination of SMV, DCV, and RBV administered for 24 weeks was shown to be effective and well tolerated in the treatment of post-OLT HCV GT1b-infected patients.

Efficacy and safety of simeprevir with PegIFN/ribavirin in naïve or experienced patients infected with chronic HCV genotype 4.

BACKGROUND & AIMS: Simeprevir (SMV) is a once-daily (QD), oral hepatitis C virus (HCV) NS3/4A protease inhibitor approved for treatment of genotype (GT) 1 and GT4 infection. This Phase III, open-label, single-arm study (RESTORE; NCT01567735) evaluated efficacy/safety of SMV with peginterferon-α-2a/ribavirin (PR) in patients with chronic HCV GT4 infection. METHODS: 107 patients were included. Treatment-naïve (n=35) and prior relapse patients (n=22) received SMV 150mg QD+PR (12 weeks), followed by PR alone (12 or 36 weeks, response-guided [HCV RNA <25IU/ml detectable/undetectable at week 4 and <25IU/ml undetectable at week 12]). Prior non-responders (partial, n=10; null, n=40) received SMV/PR (12 weeks), followed by PR for 36 weeks. The primary endpoint was sustained virologic response 12 weeks after end of treatment (SVR12). RESULTS: Median age: 49.0years; 28.0% Black/African; 7.5% IL28B CC; 28.8% METAVIR F4. Overall, 65.4% (70/107) of patients achieved SVR12 (82.9% [29/35] treatment-naïve; 86.4% [19/22] prior relapsers; 60.0% [6/10] prior partial responders; 40.0% [16/40] prior null responders). In treatment-naïve and prior relapser patients fulfilling response-guided criteria for 24 weeks of treatment (88.6% [31/35] and 90.9% [20/22]), SVR12 rates were high: 93.5% [29/31] and 95.0% [19/20], respectively. Overall on-treatment failure and relapse rates were 23.4% (25/107) and 14.6% (12/82), respectively. Adverse events (AEs) were mainly grade 1/2; serious AEs were infrequent (4.7%) and considered unrelated to SMV. CONCLUSIONS: Efficacy and safety of SMV 150mg QD for 12 weeks with PR in treatment-naïve or -experienced patients with chronic HCV GT4 infection were in line with previous reports for HCV GT1 infection.

Simeprevir (TMC435) with pegylated interferon/ribavirin in patients coinfected with HCV genotype 1 and HIV-1: a phase 3 study.

BACKGROUND: Simeprevir is an oral, once-daily, hepatitis C virus (HCV) NS3/4A protease inhibitor for the treatment of chronic HCV genotype 1 infection. Human immunodeficiency virus (HIV) coinfection accelerates progression of liver disease. This uncontrolled, open-label trial explored the safety and efficacy of simeprevir in patients with HCV genotype 1/HIV type 1 (HIV-1) coinfection. METHODS: Patients received simeprevir (150 mg once daily) with pegylated interferon alfa-2a/ribavirin (peg-IFN/RBV) for 12 weeks. Noncirrhotic HCV treatment-naive patients and prior relapsers received response-guided therapy (RGT) with peg-IFN/RBV for 24 or 48 weeks. Prior null responders, prior partial responders, and patients with cirrhosis received peg-IFN/RBV for 48 weeks. The primary endpoint was sustained virologic response 12 weeks after the end of treatment (SVR12). RESULTS: One hundred and six patients (93 on antiretroviral therapy) were enrolled and treated. SVR12 rates were 79.2% in HCV treatment-naive patients, 57.1% in prior null responders, 86.7% in prior relapsers, and 70.0% in prior partial responders. Fifty-four of 61 eligible patients (88.5%) met RGT criteria for 24 weeks of peg-IFN/RBV, of whom 87.0% (47/54) achieved SVR12. SVR12 rates were 80.0% (36/45) and 63.6% (14/22) for patients with METAVIR scores of F0-F2 and F3-F4, respectively. Common adverse event (AE) rates were consistent with peg-IFN/RBV therapy (fatigue, headache, nausea, neutropenia). Most AEs were grade 1/2; serious AEs occurred in 5.7% of patients, none of which were fatal. CONCLUSIONS: Simeprevir was generally well tolerated with safety similar to that observed in HCV-monoinfected patients and high SVR12 rates in HCV treatment-naive patients, prior relapsers, prior partial responders, and prior null responders with HIV-1 coinfection. CLINICAL TRIALS REGISTRATION: NCT01479868.

Correction to: Pharmacokinetics, Safety and Tolerability of JNJ-56136379, a Novel Hepatitis B Virus Capsid Assembly Modulator, in Healthy Subjects.

In the original article Ninth and Tenth authors were incorrectly omitted from the author group. The correct author group is Joris Vandenbossche, Wolfgang Jessner, Maarten van den Boer, Jeike Biewenga, Jan Martin Berke, Willem Talloen, Loeckie De Zwart, Jan Snoeys, Koen Vandyck, John Fry, Jeysen Yogaratnam.

Pharmacokinetics, Safety and Tolerability of JNJ-56136379, a Novel Hepatitis B Virus Capsid Assembly Modulator, in Healthy Subjects.

INTRODUCTION: Hepatitis B viral capsid assembly is an attractive target for new antiviral treatments. JNJ-56136379 (JNJ-6379) is a potent capsid assembly modulator in vitro with a dual mode of action. In Part 1 of this first-in-human study in healthy adults, the pharmacokinetics (PK), safety and tolerability of JNJ-6379 were evaluated following single ascending and multiple oral doses. METHODS: This was a double-blind, randomized, placebo-controlled study in 30 healthy adults. Eighteen subjects were randomized to receive single doses of JNJ-6379 (25 to 600 mg) or placebo. Twelve subjects were randomized to receive 150 mg JNJ-6379 or placebo twice daily for 2 days, followed by 100 mg JNJ-6379 or placebo daily for 10 days. RESULTS: The maximum observed plasma concentration and the area under the curve increased dose proportionally from 25 to 300 mg JNJ-6379. Following multiple dosing, steady-state conditions were achieved on day 8. Steady-state clearance was similar following single and multiple dosing, suggesting time-linear PK. All adverse events (AEs) reported were mild to moderate in severity. There were no serious AEs or dose-limiting toxicities and no apparent relationship to dose for any AE. CONCLUSION: JNJ-6379 was well tolerated in this study. Based on the safety profile and plasma exposures of JNJ-6379 in healthy subjects, a dosing regimen was selected for Part 2 of this study in patients with chronic hepatitis B. This is anticipated to achieve trough plasma exposures of JNJ-6379 at steady state of more than three times the 90% effective concentration of viral replication determined in vitro. TRIAL REGISTRATION: Clinicaltrials.gov identifier, NCT02662712. FUNDING: Janssen Pharmaceutica.

Very early viral kinetics on interferon treatment in chronic hepatitis C virus genotype 4 infection.

BACKGROUND: Interferon (IFN)-resistant hepatitis C virus strains limit efficacy of antiviral combination therapy in patients infected with genotypes 1 and 4. A single test dose of IFN was useful to identify non-responders to IFN-alpha2b/ribavirin (RBV) or likely non-responders to pegylated (PEG)-IFN-alpha2a/RBV therapy in genotype 1 patients. Our aim was to investigate this approach in genotype 4 patients. METHODS: Viral load was measured in 46 patients before and 24 h after 10 megaunits (MU) IFN-alpha2b, and before and during 2 weeks of daily 5 MU IFN-alpha2b administration. Thereafter, patients received 48 weeks combination therapy with either 180 microg PEG-IFN-alpha2a/week (n=33), 1.5 microg/kg PEG-IFN-alpha2b/week (n=7) or 5 MU IFN-alpha2b/2 days (n=6), along with 1-1.2g RBV/day. For prediction analysis the largest group (PEG-IFN-alpha2a) was evaluated only. RESULTS: Median 24 h log10 change after 10 MU IFN-alpha2b was 1.15 (range 0.08-2.48) and after 5 MU IFN-alpha2b was 0.81 (-0.12-2.22; P<0.0001). Log10 changes after 2 weeks on 5 MU IFN-alpha2b daily and 24 h after 10 MU were the best predictors of early virological response (defined by negativity of a standard qualitative PCR) to PEG-IFN-alpha2a/RBV combination therapy (area under curve [AUC]=0.97; P<0.001, receiver operating characteristics), 24 h log10 change after 10 MU was the best predictor of sustained virological response (SVR; AUC=0.91, P=0.001). CONCLUSION: As in genotype 1 patients, there is large variation in IFN responsiveness, including the presence of resistant strains, in genotype 4 patients. A 24 h log10 change after 10 MU IFN-alpha2b is an excellent predictor of SVR on PEG-IFNalpha2a/RBV combination therapy. This test may be useful to obtain homogeneous groups for clinical studies and could help in clinical decision making.

Simeprevir versus telaprevir with peginterferon and ribavirin in previous null or partial responders with chronic hepatitis C virus genotype 1 infection (ATTAIN): a randomised, double-blind, non-inferiority phase 3 trial.

BACKGROUND: We did a phase 3 study in previous non-responders with chronic hepatitis C virus (HCV) genotype 1 infection and compensated liver disease that related to the standard of care for these patients at the time this study was initiated. We investigated whether simeprevir is non-inferior in terms of efficacy to telaprevir, each in combination with peginterferon alfa-2a and ribavirin. METHODS: We did this randomised, double-blind, phase 3 trial at 169 investigational sites in 24 countries. We enrolled adults (≥18 years) with chronic HCV genotype 1 infection, compensated liver disease, and plasma HCV RNA higher than 10 000 IU/mL who were null or partial responders during at least one previous course of peginterferon alfa-2a and ribavirin treatment. We randomly assigned (1:1) patients (stratified by HCV genotype 1 subtype [1a plus other/1b] and previous treatment response [partial or null]) to receive simeprevir (150 mg once a day) plus telaprevir placebo (three times a day 7-9 h apart) or telaprevir (750 mg three times a day) plus simeprevir placebo (once a day) in combination with peginterferon alfa-2a and ribavirin for 12 weeks followed by 36 weeks of peginterferon alfa-2a and ribavirin alone. The primary efficacy endpoint was sustained virological response 12 weeks after end of treatment (SVR12) in the intention-to-treat and the per-protocol population. We compared groups with the Cochran-Mantel-Haenszel test. We established a non-inferiority margin of 12%. Adverse events were reported descriptively. This trial is registered with ClinicalTrials.gov, number NCT01485991. FINDINGS: Patient screening began on Jan 19, 2012, and the last visit was on April 7, 2014. We included 763 patients (472 previous null responders [62%]). Simeprevir and peginterferon alfa-2a and ribavirin was non-inferior to telaprevir and peginterferon alfa-2a and ribavirin for SVR12 (54% [203/379] vs 55% [210/384]; difference -1·1%, 95% CI -7·8 to 5·5; p=0·0007). SVR12 was achieved in 70% (101/145) versus 68% (100/146) of previous partial responders and 44% (102/234) versus 46% (110/238) of previous null responders with simeprevir and peginterferon alfa-2a and ribavirin and telaprevir and peginterferon alfa-2a and ribavirin treatment, respectively. We recorded differences between treatment groups in simeprevir or telaprevir-related adverse events (69% [261/379] in the simeprevir group vs 86% [330/384] in the telaprevir group), serious adverse events (2% [8/379] vs 9% [33/384]), and adverse events leading to simeprevir or telaprevir discontinuation (2% [7/379] vs 8% [32/384]). INTERPRETATION: Simeprevir once a day with peginterferon alfa-2a and ribavirin was well tolerated in HCV genotype 1-infected previous non-responders and was non-inferior to telaprevir, thus providing an alternative treatment in areas of the world where all-oral HCV regimens are not available or accessible. FUNDING: Janssen.

Hepatitis C viral dynamics: basic concept and clinical significance.

Viral dynamics is a concept analyzing the time course of treatment-induced changes in blood virion concentration (kinetics) to derive conclusions of where, when and how in the living organism virions are produced or eliminated. Originally applied to human immunodeficiency virus type 1 and hepatitis B virus, it has elucidated mechanisms of antiviral therapy in hepatitis C virus infection as well. This review summarizes key aspects of mathematical modeling as well as important clinical applications, namely induction therapy and prediction of virologic response to treatment. Furthermore, limitations of currently available quantitative assays will be discussed.

Retreatment of patients with chronic hepatitis C not responding to interferon/ribavirin combination therapy with daily interferon plus ribavirin plus amantadine.

There is currently no accepted therapeutic regimen for patients with chronic hepatitis C who failed to respond to standard combination treatment with interferon-alpha plus ribavirin. We investigated triple combination treatment with induction dosing of interferon-alpha plus ribavirin plus amantadine in these difficult-to-treat patients. Nonresponders (n = 67), breakthroughs (n = 16) and relapsers (n = 19) to previous interferon/ribavirin combination treatment of at least 6 months were included. For the first 16 weeks, patients received interferon-alpha2a 6 MU daily, ribavirin 800-1200 mg/d, and amantadine 200 mg/d. In cases of undetectable HCV RNA at week 12, treatment was continued with interferon-alpha2a 6 MU every other day and the same doses of ribavirin and amantadine until week 48. In cases of HCV RNA positivity at week 12, treatment was stopped. A total of 102 patients were enrolled (80%: genotype 1, 19%: cirrhosis). HCV RNA was negative in 35/102 patients (34%) at week 12 and in 27/ 102 patients (26%) at the end of treatment. Virological response was sustained in 15/102 patients (15%). On-treatment virological response was higher in previous relapsers/breakthroughs than in previous nonresponders (week 12: 49% vs. 27%, p < 0.05; week 48: 46% vs. 16%, p < 0.01) but no such difference was found for sustained virological response (20% vs. 12%, NS). In conclusion, triple combination treatment with daily interferon-alpha plus ribavirin plus amantadine for 3 months can induce virological response in a considerable number of nonresponders/relapsers to previous dual combination treatment, but the sustained virological response rate remains low.

Transcellular water transport in hepatobiliary secretion and role of aquaporins in liver.

In the context of the osmotic model of bile formation, we used isolated rat hepatocyte couplets and performed volume measurements by video image analysis to analyze the transport of water between the bile canalicular lumen, liver cells and the surrounding bathing medium. Increasing bath osmolarity by the addition of sucrose led to shrinkage of cells that preceded shrinkage of the canalicular lumen by approx. 1 sec. Thermodynamic modeling of water transport across the basolateral and apical cell membranes and across a paracellular pathway (tight junctions) revealed high hydraulic water permeabilities of both cell membranes of approx. 3*10(-4) cm*sec(-1)*(osmol/kg)(-1) indicating transcellular water flux between bathing medium and bile. Tight junctions exhibited low water permeability but allowed for electrolyte permeation that enables canalicular spaces to shrink below van't Hoff equilibrium during the osmotic maneuver. The results are discussed with respect to the role of different types of membrane aquaporins being expressed in hepatocytes.

Sustained remission of chronic hepatitis C after acute hepatitis B superinfection.

We observed acute HBV superinfection on chronic HCV genotype 1 infection in a 29-y-old injection drug user. On presentation HCV-RNA was already negative and remained so for at least 7 months thereafter. We speculate that clearance of HCV-HBV coinfected cells by HBV-specific immunity might be a mechanism of HCV eradication.

Diagnostic value of quantitative hepatic copper determination in patients with Wilson's Disease.

BACKGROUND & AIMS: A 5-fold increase of hepatic copper concentration is considered as the best available test for diagnosis of hepatic Wilson's disease (WD). However, the sensitivity and specificity of this test have never been fully investigated. METHODS: Copper content was measured by flame atomic absorption spectroscopy in 114 liver biopsies obtained at diagnosis of WD, in 219 patients with noncholestatic liver diseases (including 144 with chronic hepatitis C and 44 with nonalcoholic fatty liver disease), and in 26 without evidence of liver disease. RESULTS: Liver copper content was >250 microg/g in 95 WD patients (83.3%), between 50 and 250 microg/g in 15, and below 50 microg/g in 4. It did not correlate with age (r(2) = .003), the grade of fibrosis, or the presence of stainable copper. Liver copper content was >250 or between 50 and 250 microg/g in 3 (1.4%) and 20 (9.1%) of 219 patients with noncholestatic liver diseases, respectively. By lowering the cutoff from 250 to 75 microg/g, the sensitivity of liver copper content to diagnose WD increased from 83.3% (95% confidence interval, 75.2%-89.6%) to 96.5% (91.3%-99.1%), but the specificity decreased from 98.6% (96.0%-99.7%) to 95.4% (91.8%-97.8%). CONCLUSIONS: There is no gold standard for the diagnosis of WD. Liver copper content is a useful parameter, but a value below 250 microg/g does not exclude WD. Diagnosis requires the combination of a variety of clinical and biochemical tests.

Correction of CFTR malfunction and stimulation of Ca-activated Cl channels restore HCO3- secretion in cystic fibrosis bile ductular cells.

In view of the occurrence of hepatobiliary disorders in cystic fibrosis (CF) this study addresses the role of the cystic fibrosis transmembrane conductance regulator (CFTR) and of Ca(2+)-activated Cl(-) channels in promoting HCO3- secretion in bile ductular cells. Human cholangiocytes were isolated from control livers and from 1 patient with CF (DeltaF508/G542X mutations). Single channel and whole cell currents were analyzed by patch clamp techniques, and HCO3- secretion was determined by fluorometric analysis of the rate of recovery of intracellular pH following alkaline loading. In control cholangiocytes, both cyclic adenosine monophosphate (cAMP) and protein kinase A (PKA) catalytic subunit, activated CFTR Cl(-) channels that exhibited a nonrectifying conductance of 8 pS and appeared in clusters. Activation of Cl(-) current by cAMP was associated with an increase in the rate of HCO3- secretion. The basal rate of HCO3- secretion was lower in CF than in control cholangiocytes. In both control and CF cholangiocytes, raising intracellular Ca(2+) concentrations with ionomycin led to a parallel activation of Cl(-) current and HCO3- secretion. Consistent with reports that premature stop codon mutations (class I; e.g., G542X) can be read over by treatment with aminoglycoside antibiotics, exposure of CF cholangiocytes to gentamicin restored activation by cAMP of Cl(-) current and HCO3- secretion. The observation that activation of Ca(2+)-dependent Cl(-) channels can substitute for cystic fibrosis transmembrane conductance regulator (CFTR) in supporting HCO3- secretion and the efficacy of gentamicin in restoring CFTR function and HCO3- secretion in class I mutations are of potential clinical interest.

Hepatic iron concentration does not predict response to standard and pegylated-IFN/ribavirin therapy in patients with chronic hepatitis C.

BACKGROUND/AIMS: Iron overload is common among patients with chronic hepatitis C (CHC). In this study the role of hepatic iron concentration (HIC) and serum iron parameters was assessed to determine response to standard and pegylated interferon (IFN)/ribavirin combination therapy in patients with CHC. METHODS: Liver biopsies were obtained from 169 IFN-naïve patients (m=115, f=54, age: 40.8+/-10.7) with CHC. 140 patients were treated with standard IFN/ribavirin, 29 patients with pegylated-IFN/ribavirin. Biopsy specimens were evaluated according to the DiBisceglie scoring system and iron grading. HIC was determined by atomic absorption spectroscopy. Ferritin and transferrin saturation and presence of HFE-C282Y and H63D gene mutations were determined at baseline. RESULTS: Nonresponders to combination therapy had higher serum ferritin levels at baseline (p<0.01). There was no difference of HIC, transferrin saturation levels, and the HFE-mutation status between responders and nonresponders. Logistic regression analysis revealed serum ferritin as an independent predictor of response. HIC correlated with the DiBisceglie score (r=0.352, p<0.001), iron grading (r=0.352, p<0.001) and serum ferritin (r=0.335, P<0.001). CONCLUSIONS: Pretreatment liver iron concentration does not predict response to combination therapy in patients with CHC. In contrast, high baseline serum ferritin levels are predictors of poor response to antiviral therapy.

Sudden hearing loss in patients with chronic hepatitis C treated with pegylated interferon/ribavirin.

BACKGROUND: Sudden hearing loss has been reported on standard interferon (IFN)-alpha2 therapy. This is the first report on the occurrence of sudden hearing loss in six cases of chronic hepatitis C in temporal relation to treatment with pegylated (PEG)-IFN alfa2a or b/ribavirin combination therapy. Three patients were treated in an ongoing randomized placebo-controlled trial comparing the addition of 200 mg amantadine or placebo to the combination of 180 microg PEG-IFN alpha2a (PEGASYS, Roche, Basel, CH)/wk and 1-1.2 g ribavirin/d (COPEGUS, Roche, Nutley, USA) in de novo patients infected with HCV genotype 1. Sudden hearing loss and tinnitus developed on day 1 and after 4, 23, 25, 36, and 40 wk of treatment, respectively. CONCLUSIONS: Sudden hearing loss may occur in about 1% of patients on PEG-IFN/ribavirin combination therapy. This rate was not different to that observed in an untreated population. Possible mechanisms involved include direct ototoxicity of IFN, autoimmunity, and hematological changes. In contrast to published cases on auditory disability due to standard IFN, hearing loss did not fully resolve after discontinuation of therapy with PEG-IFN. On the other hand, symptoms did not worsen on continued treatment. Therefore, the decision whether to continue or to stop the treatment when signs of ototoxicity appear is based on the clinical judgment of the treating physician.

Rapid suppression of hematopoiesis by standard or pegylated interferon-alpha.

BACKGROUND & AIMS: Treatment of chronic hepatitis C with interferon (IFN)-alpha often has hematotoxic effects. We evaluated the effects of acute vs. chronic and standard vs. pegylated IFN-alpha on hematopoiesis. METHODS: We studied hematopoiesis in 46 patients with chronic hepatitis C receiving single high-dose IN-Falpha2b followed by daily dose standard or weekly pegylated IFN before combination antiviral therapy. RESULTS: Single high-dose therapy resulted in a significant drop in hemoglobin (HB), leukocytes, and platelet count. Although platelets, stimulated by a significant increase in thrombopoietin (TPO), and leukocytes recovered quickly, HB remained below baseline for 7 days. Daily standard or weekly pegylated IFN-alpha leads to a more pronounced drop in all 3 lineages with concomitant increases in TPO and erythropoietin (EPO). No difference was observed between standard and pegylated IFN, except for HB, which fell more during pegylated IFN therapy. Consecutive combination antiviral therapy aggravated the anemia but not the drop in leukocytes or thrombocytes. CONCLUSIONS: The drop in all 3 hematopoietic lineages through IFN-alpha treatment, high-dose standard, standard daily dose, or pegylated, is caused by a combination of bone marrow inhibition and probably some other rapid acting mechanisms. Hematopoietic growth factors are increased as a consequence but cannot overcome the bone marrow suppression.

Subclinical impairment of brain function in chronic hepatitis C infection.

BACKGROUND/AIMS: Central nervous system abnormalities such as fatigue and depression occur more frequently in chronic hepatitis C virus (HCV) infection than in many other causes of chronic liver disease. The finding that fatigue is unrelated to activity of hepatitis or mode of infection could indicate an independent effect of HCV on brain function. This study tested the hypothesis of a subclinical cognitive dysfunction in HCV-infected patients. METHODS: One-hundred untreated HCV-RNA positive biopsy-proven patients were investigated by P300 event-related potentials, a sensitive electrophysiologic test of cognitive processing. Health-related quality of life and fatigue were assessed using the SF-36 questionnaire and the Fatigue Impact Scale, respectively. RESULTS: Cognitive brain function was subclinically impaired in the cohort of HCV-infected patients as indicated by significantly prolonged P300 latencies (P=0.01 for comparison to matched healthy subjects) and reduced P300 amplitudes (P<0.001, respectively). Seventeen of the 100 HCV-infected patients had P300 latencies outside the age-adjusted normal range. Abnormal P300 characteristics were not related to the degree of histologic or biochemical activity of hepatitis, severity of fatigue or mental health impairment. CONCLUSIONS: This study demonstrates that patients with HCV infection showed a slight but significant neurocognitive impairment, possibly indicating a further extrahepatic manifestation of chronic hepatitis C.