Quantitative tests of liver function measure hepatic improvement after sustained virological response: results from the HALT-C trial

Editorial: Reading the cholate - A new gateway to portal hypertension and oesophageal varices

This article is linked to Hassanein et al papers. To view these articles, visit https://doi.org/10.1111/apt.18054 and https://doi.org/10.1111/apt.18128.

Hepatic Dysfunction Quantified by HepQuant DuO Outperforms Child-Pugh Classification in Predicting the Pharmacokinetics of Ampreloxetine

HepQuant tests quantify liver function from clearance of deuterium- and 13C-labeled cholates administered either intravenously and orally (SHUNT) or orally (DuO). Hepatic impairment studies have relied on clinical or laboratory criteria like Child-Pugh classification to categorize the degree of hepatic dysfunction. We compared HepQuant tests with Child-Pugh classification in predicting the pharmacokinetics of ampreloxetine. Twenty-one subjects with hepatic impairment (8 Child-Pugh A, 7 Child-Pugh B, and 6 Child-Pugh C), and 10 age- and sex-matched controls were studied. The pharmacokinetics of ampreloxetine were measured after oral administration of a single dose of 10 mg. Disease severity index (DSI), portal-systemic shunting (SHUNT%), hepatic reserve, and hepatic filtration rates (HFRs) were measured from serum samples obtained after intravenous administration of [24-13C]-cholate and oral administration of [2,2,4,4-2H]cholate. Ampreloxetine plasma exposure (AUC0-inf) was similar to controls in Child-Pugh A, increased 1.7-fold in subjects with Child-Pugh B, and 2.5-fold in subjects with Child-Pugh C and correlated with both Child-Pugh score and HepQuant parameters. The variability observed in ampreloxetine exposure (AUC0-inf) in subjects with moderate (Child-Pugh B) and severe hepatic impairment (Child-Pugh C) was explained by HepQuant parameters. Multivariable regression models demonstrated that DSI, SHUNT%, and Hepatic Reserve from SHUNT and DuO were superior predictors of ampreloxetine exposure (AUC0-inf) compared to Child-Pugh score. HepQuant DSI, SHUNT%, and hepatic reserve were more useful predictors of drug exposure than Child-Pugh class for ampreloxetine and thus may better optimize dose recommendations in patients with liver disease. The simple-to-administer, oral-only DuO version of the HepQuant test could enhance clinical utility.

Hepatic improvement within 27 days of avenciguat treatment in Child-Pugh A cirrhosis detected by an oral cholate challenge test

New methods for measuring hepatic improvement in clinical trials and the clinic are needed. One new method, HepQuant SHUNT, detected dose-dependent improvements in hepatic function and portal physiology in the phase 1b study (NCT03842761) of avenciguat, an activator of soluble guanylyl cyclase that is being developed for the treatment of portal hypertension. Herein, we examined whether HepQuant Duo, an easy-to-administer test version, could similarly detect the effects of avenciguat. Twenty-three patients with Child-Pugh A cirrhosis and liver stiffness >15 kPa received either a placebo (n = 5) or a maximum twice-daily avenciguat dose of 1, 2, or 3 mg (n = 6 per group) for 28 days. The DuO test was performed at baseline and on days 11 and 27 in each subject. The test involved administering 40 mg of d4-cholate orally, measuring d4-cholate concentrations in serum at 20 and 60 minutes, and calculating portal hepatic filtration rate, disease severity index, portal-systemic shunting (SHUNT%), and hepatic reserve (HR%). Avenciguat demonstrated dose-dependent improvement in all test parameters. Changes from baseline in SHUNT% after 27 days' treatment were 0.1 ± 9.0% for placebo, 1.7 ± 5.5% for 1 mg twice-daily, -3.2 ± 2.7% for 2 mg twice-daily, and -6.1 ± 5.0% for 3 mg twice-daily (paired t test for change from baseline p = 0.98, 0.48, 0.04, and 0.03, respectively). The changes detected by HepQuant DuO were similar to those previously observed and reported for HepQuant SHUNT. The results support further study of avenciguat in treating portal hypertension and spotlight the utility of HepQuant DuO in the development of drug therapy for liver disease. HepQuant DuO facilitates the use of function testing to measure hepatic improvement in clinical trials and the clinic.

Within-individual reproducibility of a dual sample oral cholate challenge test (DuO) and simplified versions of the HepQuant SHUNT test

Current noninvasive liver tests measure fibrosis, inflammation, or steatosis and do not measure function. The HepQuant platform of noninvasive tests uniquely assesses both liver function and physiology through the hepatic uptake of stable isotopes of cholate. However, the prototypical HepQuant SHUNT test (SHUNT V1.0) is cumbersome to administer, requiring intravenous and oral administration of cholate and six peripheral venous blood samples over 90 min. To alleviate the burden of test administration, we explored whether an oral only (DuO) version, and other simplified versions, of the test could provide reproducible measurements of liver function. DuO requires only oral dosing and two blood samples over 60 min. The simplified SHUNT test versions were SHUNT V1.1 (oral and IV dosing but four blood samples) and SHUNT V2.0 (oral and IV dosing but only two blood samples over 60 min). In this paper, we describe the reproducibility of DuO and the simplified SHUNT tests relative to that of SHUNT V1.0; equivalency is described in a separate paper. Data from two studies comprising 236 SHUNT tests in 94 subjects were analyzed retrospectively by each method. All simplified methods were highly reproducible across test parameters with intraclass correlation coefficients >0.93 for test parameters Disease Severity Index (DSI) and Hepatic Reserve. DuO and SHUNT V2.0 improved reproducibility in measuring portal-systemic shunting (SHUNT%). These simplified tests, particularly DuO and SHUNT V2.0, are easier to administer and less invasive, thus, having the potential to be more widely accepted by care providers administering the test and by patients receiving the test.

Compartmental model describing the physiological basis for the HepQuant SHUNT test

The HepQuant SHUNT test quantifies hepatic functional impairment from the simultaneous clearance of cholate from the systemic and portal circulations for the purpose of monitoring treatment effects or for predicting risk for clinical outcome. Compartmental models are defined by distribution volumes and transfer rates between volumes to estimate parameters not defined by noncompartmental analyses. Previously, a noncompartmental analysis method, called the minimal model (MM), demonstrated reproducible and reliable measures of liver function (Translational Research 2021). The aim of this study was to compare the reproducibility and reliability of a new physiologically based compartmental model (CM) vs the MM. Data were analyzed from 16 control, 16 nonalcoholic steatohepatitis (NASH), and 16 hepatitis C virus (HCV) subjects, each with 3 replicate tests conducted on 3 separate days. The CM describes transfer of cholates between systemic, portal, and liver compartments with assumptions from measured or literature-derived values and unknown parameters estimated by nonlinear least-squares regression. The CM was compared to the MM for 6 key indices of hepatic disease in terms of intraclass correlation coefficient (ICC) with a lower acceptable limit of 0.7. The CM correlated well with the MM for disease severity index (DSI) with R² (95% confidence interval) of 0.96 (0.94-0.98, P < 0.001). Acceptable reproducibility (ICC > 0.7) was observed for 6/6 and 5/6 hepatic disease indices for CM and MM, respectively. SHUNT, a measure of the absolute bioavailability, had ICC of 0.73 (0.60-0.83, P = 0.3095) for MM and 0.84 (0.76-0.90, P = 0.0012) for CM. The CM, but not the MM, allowed determination of anatomic shunt and hepatic extraction and improved the within individual reproducibility.

Kinetics of emergence of liver complications in hepatitis C virus infected patients and advanced fibrosis, with and without HIV-coinfection, after sustained virological response

OBJECTIVE

There is scarce available evidence on the distribution over time of liver complications emergence in hepatitis C virus (HCV)-infected patients who achieve sustained virological response (SVR) with direct-acting antiviral (DAA)-based therapy. Therefore, we aimed at describing the kinetics of liver-related events appearance in this setting.

DESIGN

A multicentric prospective cohort study.

METHODS

HCV-monoinfected and HIV/HCV-coinfected patients from GEHEP-011 cohort, whose inclusion criteria were had achieved SVR with DAA-based therapy; liver stiffness prior to starting treatment at least 9.5 kPa; and available liver stiffness measurement at SVR. SVR was considered as the baseline time-point.

RESULTS

One thousand and thirty-five patients were included, 664 (64%) coinfected with HIV. Before DAA-based therapy, 63 (6.1%) individuals showed decompensated cirrhosis. After SVR, 51 (4.9%) patients developed liver complications. Median (Q1-Q3) time to the emergence of hepatic events was hepatic encephalopathy 11 (7-24) months, ascites 14 (6-29) months, hepatocellular carcinoma (HCC) 17 (11-42) months and portal hypertension gastrointestinal bleeding (PHGB) 28 (22-38) months (P = 0.152). We define two profiles of liver complications: those emerging earlier (encephalopathy and ascites) and, those occurring continuously during the follow-up (HCC, PHGB) [median (Q1-Q3) time to emergence 12.7 (6.6-28.2) months vs. 25.4 (12.5-41.53) months, respectively (P = 0.026)].

CONCLUSION

The vast majority of HCV-infected patients who develop liver complications after reaching SVR with DAA do it within 3 years after SVR time-point. Specifically, hepatic encephalopathy and ascites do not usually emerge after this period. Conversely, HCC and PHGB may occur in longer term. It is critical to identify patients at risk of developing hepatic events to continue performing surveillance for them.

The within-individual reproducibility of the disease severity index from the HepQuant SHUNT test of liver function and physiology

The HepQuant SHUNT test quantifies liver function and blood flow using systemic and portal clearances of cholate. The test can identify the risk of well-compensated patients to develop complications of cirrhosis. To confirm the reliability of a single HepQuant SHUNT test we defined its within-individual reproducibility. Healthy subjects (n = 16), 16 with nonalcoholic steatohepatitis (NASH), and 16 with chronic hepatitis C virus (HCV) underwent 3 HepQuant SHUNT tests on 3 separate days within 30 days. The test involves simultaneous administration of 20 mg 13C-cholate IV and 40 mg d4-cholate PO, and subsequent collection of 3 mL blood samples at 5, 20, 45, 60, and 90 minutes. Clearances are expressed as systemic and portal hepatic filtration rate. Portal-systemic shunting (SHUNT), a disease severity index (DSI), and an estimate of DSI (STAT) are calculated from the clearances. Reproducibility was determined by the intraclass correlation coefficient (ICC > 0.70) and Bland-Altman analysis. Equal numbers of NASH and HCV patients had either early (F0-F2) or advanced (F3/F4) stages of fibrosis. All F3/F4 subjects were clinically compensated. The intraclass correlation coefficient (ICC) for DSI was 0.94 (0.90-0.96 95% confidence interval) indicating excellent reproducibility. The other test parameters had ICCs ranging from 0.74 (SHUNT) to 0.90 (STAT). In Bland-Altman analysis, the mean of differences between measurements of DSI was 0.13 with standard deviation 2.12. The excellent reproducibility of the HepQuant SHUNT test, particularly DSI, supports the use this minimally invasive, blood-based test as a reliable test of liver function and physiology.

Potential use of metabolic breath tests to assess liver disease and prognosis: has the time arrived for routine use in the clinic?

The progression of liver disease may be unique among organ system diseases in that progressive fibrosis compromises not only the sufficiency of hepatocyte mass but also impairs blood flow to the liver, resulting in porto-systemic shunting. Although liver biopsy as an assessment of fibrosis has become the key biomarker of and target for new therapies, it is invasive and subject to sampling error, and cannot quantify metabolic function or porto-systemic shunting. Measurement of the hepatic venous pressure gradient accommodates some of the deficiencies of biopsy but requires expertise not widely available and misses minor changes in hepatocellular mass and thereby information about metabolic function. Thus, an unmet need in clinical hepatology remains unfulfilled: a noninvasive biomarker which quantitates both the hepatocellular insufficiency and porto-systemic shunting inherent in progressive hepatic fibrosis. Ideally, such a biomarker should correlate with clinical endpoints including liver-related survival and cirrhotic complications, be performed at the point-of-care, and be affordable and easy to use. This review, an expert opinion, summarizes background and recent data suggesting that metabolic breath tests may now meet these requirements and have a valid place in clinical hepatology to supplant the time-honoured assessment of hepatic fibrosis.

Defining long-term outcomes with living donor liver transplantation in North America

OBJECTIVES

To compare long-term survival of living donor liver transplant (LDLT) at experienced transplant centers with outcomes of deceased donor liver transplant and identify key variables impacting patient and graft survival.

BACKGROUND

The Adult-to-Adult Living Donor Liver Transplantation Cohort Study is a prospective multicenter National Institutes of Health study comparing outcomes of LDLT and deceased donor liver transplant and associated risks.

METHODS

Mortality and graft failure for 1427 liver recipients (963 LDLT) enrolled in the Adult-to-Adult Living Donor Liver Transplantation Cohort Study who received transplant between January 1, 1998, and January 31, 2014, at 12 North American centers with median follow-up 6.7 years were analyzed using Kaplan-Meier and multivariable Cox models.

RESULTS

Survival probability at 10 years was 70% for LDLT and 64% for deceased donor liver transplant. Unadjusted survival was higher with LDLT (hazard ratio = 0.76, P = 0.02) but attenuated after adjustment (hazard ratio = 0.98, P = 0.90) as LDLT recipients had lower mean model for end-stage liver disease (15.5 vs 20.4) and fewer received transplant from intensive care unit, were inpatient, on dialysis, were ventilated, or with ascites. Posttransplant intensive care unit days were less for LDLT recipients. For all recipients, female sex and primary sclerosing cholangitis were associated with improved survival, whereas dialysis and older recipient/donor age were associated with worse survival. Higher model for end-stage liver disease score was associated with increased graft failure. Era of transplantation and type of donated lobe did not impact survival in LDLT.

CONCLUSIONS

LDLT provides significant long-term transplant benefit, resulting in transplantation at a lower model for end-stage liver disease score, decreased death on waitlist, and excellent posttransplant outcomes. Recipient diagnosis, disease severity, renal failure, and ages of recipient and donor should be considered in decision making regarding timing of transplant and donor options.Clinical Trials ID: NCT00096733.

Sorting out cirrhosis: mechanisms of non-response to hepatitis C therapy

Although cirrhosis has long been recognized as an important negative predictor of treatment response for hepatitis C virus (HCV) therapy, the mechanisms underlying this association remain relatively poorly understood. Treatment has progressed rapidly with the introduction of highly effective all-oral therapies, with promising outcomes even in patients with advanced cirrhosis. However, even with the new therapies, it is clear that patients with cirrhosis require special attention. Efficacy continues to be somewhat reduced compared to non-cirrhotic patients and safety is an important concern. In this review, we explore the reasons for treatment non-response in patients with cirrhosis. We focus on how cirrhosis impacts on four important areas including drug delivery, drug uptake and metabolism, immune responses and drug toxicity with examples from the clinical and basic literature. Fortunately, as treatment continues to progress, many of the challenges of treating patients with cirrhosis will become less and less problematic.

Noninvasive assessment of liver function

PURPOSE OF REVIEW

It is our opinion that there is an unmet need in hepatology for a minimally or noninvasive test of liver function and physiology. Quantitative liver function tests define the severity and prognosis of liver disease by measuring the clearance of substrates whose uptake or metabolism is dependent upon liver perfusion or hepatocyte function. Substrates with high-affinity hepatic transporters exhibit high 'first-pass' hepatic extraction and their clearance measures hepatic perfusion. In contrast, substrates metabolized by the liver have low first-pass extraction and their clearance measures specific drug metabolizing pathways.

RECENT FINDINGS

We highlight one quantitative liver function test, the dual cholate test, and introduce the concept of a disease severity index linked to clinical outcome that quantifies the simultaneous processes of hepatocyte uptake, clearance from the systemic circulation, clearance from the portal circulation, and portal-systemic shunting.

SUMMARY

It is our opinion that dual cholate is a relevant test for defining disease severity, monitoring the natural course of disease progression, and quantifying the response to therapy.

Processes to manage analyses and publications in a phase III multicenter randomized clinical trial

Background

The timely publication of findings in peer-reviewed journals is a primary goal of clinical research. In clinical trials, the processes leading to publication can be complex from choice and prioritization of analytic topics through to journal submission and revisions. As little literature exists on the publication process for multicenter trials, we describe the development, implementation, and effectiveness of such a process in a multicenter trial.

Methods

The Hepatitis C Antiviral Long-Term Treatment against Cirrhosis (HALT-C) trial included a data coordinating center (DCC) and clinical centers that recruited and followed more than 1,000 patients. Publication guidelines were approved by the steering committee, and the publications committee monitored the publication process from selection of topics to publication.

Results

A total of 73 manuscripts were published in 23 peer-reviewed journals. When manuscripts were closely tracked, the median time for analyses and drafting of manuscripts was 8 months. The median time for data analyses was 5 months and the median time for manuscript drafting was 3 months. The median time for publications committee review, submission, and journal acceptance was 7 months, and the median time from analytic start to journal acceptance was 18 months.

Conclusions

Effective publication guidelines must be comprehensive, implemented early in a trial, and require active management by study investigators. Successful collaboration, such as in the HALT-C trial, can serve as a model for others involved in multidisciplinary and multicenter research programs.

Trial registration

The HALT-C Trial was registered with clinicaltrials.gov (NCT00006164).

Detection of hepatocellular carcinoma in hepatitis C patients: biomarker discovery by LC-MS

Hepatocellular carcinoma (HCC) accounts for most cases of liver cancer worldwide; contraction of hepatitis C (HCV) is considered a major risk factor for liver cancer even when individuals have not developed formal cirrhosis. Global, untargeted metabolic profiling methods were applied to serum samples from patients with either HCV alone or HCC (with underlying HCV). The main objective of the study was to identify metabolite based biomarkers associated with cancer risk, with the long term goal of ultimately improving early detection and prognosis. Serum global metabolite profiles from patients with HCC (n=37) and HCV (n=21) were obtained using high performance liquid chromatography-mass spectrometry (HPLC-MS) methods. The selection of statistically significant metabolites for partial least-squares discriminant analysis (PLS-DA) model creation based on biological and statistical significance was contrasted to that of a traditional approach utilizing p-values alone. A PLS-DA model created using the former approach resulted in a model with 92% sensitivity, 95% specificity, and an AUROC of 0.93. A series of PLS-DA models iteratively utilizing three to seven metabolites that were altered significantly (p<0.05) and sufficiently (FC≤0.7 or FC≥1.3) showed good performance using p-values alone; the best of these PLS-DA models was capable of generating 73% sensitivity, 95% specificity, and an AUROC of 0.92. Metabolic profiles derived from LC-MS readily distinguish patients with HCC and HCV from those with HCV only. Differences in the metabolic profiles between high-risk individuals and HCC indicate the possibility of identifying the early development of liver cancer in at risk patients. The use of biological significance as a selection process prior to PLS-DA modeling may offer improved probabilities for translation of newly discovered biomarkers to clinical application.

Functional elements associated with hepatic regeneration in living donors after right hepatic lobectomy

We quantified the rates of hepatic regeneration and functional recovery for 6 months after right hepatic lobectomy in living donors for liver transplantation. Twelve donors were studied pre-donation (baseline); 8 were retested at a mean ± SD of 11±3 days after donation (T1), 10 were retested at a mean of 91±9 days after donation (T2), and 10 were retested at a mean of 185±17 days after donation (T3). Liver and spleen volumes were measured with computed tomography (CT) and single-photon emission computed tomography (SPECT). Hepatic metabolism was assessed with caffeine and erythromycin, and hepatic blood flow (HBF) was assessed with cholates, galactose, and the perfused hepatic mass (PHM) by SPECT. The regeneration rates (mL kg(-1) of body weight day(-1)) by CT were 0.60±0.22 mL from the baseline to T1, 0.05±0.02 mL from T1 to T2, and 0.01±0.01 from T2 to T3; by SPECT they were 0.54±0.20, 0.04±0.01, and 0.01±0.02, respectively. At T3, the liver volumes were 84%±7% of the baseline according to CT and 92%±13% of the baseline according to SPECT. Changes in the hepatic metabolism did not achieve statistical significance. At T1, the unadjusted clearance ratios with respect to the baseline were 0.75±0.07 for intravenous cholate (P<0.001), 0.88±0.15 for galactose (P=0.07), 0.84±0.08 for PHM (P=0.002), and 0.83±0.19 for the estimated HBF (P=0.06). At T1, these ratios adjusted per liter of liver were up to 50% greater than the baseline values, suggesting recruitment of HBF by the regenerating liver. Increased cholate shunt, increased spleen volume, and decreased platelet count, were consistent with an altered portal circulation. In conclusion, initial hepatic regeneration is rapid, accounts for nearly two-thirds of total regeneration, and is associated with increases in HBF and cholate uptake. Right lobe donation alters the portal circulation of living donors, but the long-term clinical consequences, if there are any, are unknown.

How to assess liver function?

PURPOSE OF REVIEW

The liver comprises a multitude of parenchymal and nonparenchymal cells with diverse metabolic, hemodynamic and immune functions. Available monitoring options consist of 'static' laboratory parameters, quantitative tests of liver function based on clearance, elimination or metabolite formation and scores, most notably the 'model for end-stage liver disease'. This review aims at balancing conventional markers against 'dynamic' tests in the critically ill.

RECENT FINDINGS

There is emerging evidence that conventional laboratory markers, most notably bilirubin, and the composite model for end-stage liver disease are superior to assess cirrhosis and their acute decompensation, while dynamic tests provide information in the absence of preexisting liver disease. Bilirubin and plasma disappearance rate of indocyanine green reflecting static and dynamic indicators of excretory dysfunction prognosticate unfavorable outcome, both, in the absence and presence of chronic liver disease better than other functions or indicators of injury. Although dye excretion is superior to conventional static parameters in the critically ill, it still underestimates impaired canalicular transport, an increasingly recognized facet of excretory dysfunction.

SUMMARY

Progress has been made in the last year to weigh static and dynamic tests to monitor parenchymal liver functions, whereas biomarkers to assess nonparenchymal functions remain largely obscure.

Despite poor interferon response in advanced hepatitis C virus infection, models of protease inhibitor treatment predict maximum treatment benefit

BACKGROUND

Protease inhibitors have improved sustained virological response (SVR) rates for subjects with genotype 1 hepatitis C virus infection (HCV). There is however uncertainty regarding how, and in whom, these agents should be used. In previously treated subjects, prior response to interferon has a major effect on SVR rates with protease inhibitor therapy.

AIM

To assess the benefits of treatment and to understand the utility of a stopping rule for subjects with a poor interferon response following a 4-week lead-in with pegylated interferon and ribavirin.

METHODS

Treatment responses and long-term outcomes were modelled using hypothetical 1000 subject cohorts with 5 years of follow-up. Treatment strategies were compared with number needed to treat (NNT) and comparative effectiveness approaches.

RESULTS

Over 5 years of follow-up the NNT to prevent liver-related mortality for subjects with advanced fibrosis was substantially lower than that for subjects with all fibrosis stages (18 vs. 60) indicating particular benefit in this high-risk population. The use of a stopping rule for subjects with advanced fibrosis and a poor interferon response after a 4-week lead-in reduces the number of subjects exposed to a protease inhibitor by 55%. However, 33% fewer liver-related deaths are prevented using this strategy, indicating that there is unacceptable harm associated with this approach over a 5-year follow-up period.

CONCLUSIONS

Subjects with advanced fibrosis should be prioritised for triple therapy on the basis of need. Treatment should be continued regardless of initial interferon response to maximise the early prevention of hepatitis C virus-related mortality.

Quantitative liver function tests improve the prediction of clinical outcomes in chronic hepatitis C: results from the Hepatitis C Antiviral Long-term Treatment Against Cirrhosis Trial

Risk for future clinical outcomes is proportional to the severity of liver disease in patients with chronic hepatitis C virus (HCV). We measured disease severity by quantitative liver function tests (QLFTs) to determine cutoffs for QLFTs that identified patients who were at low and high risk for a clinical outcome. Two hundred and twenty-seven participants in the Hepatitis C Antiviral Long-term Treatment Against Cirrhosis (HALT-C) Trial underwent baseline QLFTs and were followed for a median of 5.5 years for clinical outcomes. QLFTs were repeated in 196 patients at month 24 and in 165 patients at month 48. Caffeine elimination rate (k(elim)), antipyrine (AP) clearance (Cl), MEGX concentration, methionine breath test (MBT), galactose elimination capacity (GEC), dual cholate (CA) clearances and shunt, perfused hepatic mass (PHM), and liver and spleen volumes (by single-photon emission computed tomography) were measured. Baseline QLFTs were significantly worse (P = 0.0017 to P < 0.0001) and spleen volumes were larger (P < 0.0001) in the 54 patients who subsequently experienced clinical outcomes. QLFT cutoffs that characterized patients as "low" and "high risk" for clinical outcome yielded hazard ratios ranging from 2.21 (95% confidence interval [CI]: 1.29-3.78) for GEC to 6.52 (95% CI: 3.63-11.71) for CA clearance after oral administration (Cl(oral)). QLFTs independently predicted outcome in models with Ishak fibrosis score, platelet count, and standard laboratory tests. In serial studies, patients with high-risk results for CA Cl(oral) or PHM had a nearly 15-fold increase in risk for clinical outcome. Less than 5% of patients with "low risk" QLFTs experienced a clinical outcome.

CONCLUSION

QLFTs independently predict risk for future clinical outcomes. By improving risk assessment, QLFTs could enhance the noninvasive monitoring, counseling, and management of patients with chronic HCV.

Very low viral load (VLVL) relapse following treatment of naïve patients with chronic hepatitis C

BACKGROUND

Sustained virologic response (SVR) to treatment of naïve patients with chronic hepatitis C (HCV) with pegylated interferon and ribavirin is 50-60%. Patients who relapse have a poor response to re-treatment. We report a group of relapse patients with SVR to low-dose re-treatment after 6 months.

AIM

Characterization of HCV relapse patients with very low viral load (VLVL) (HCV RNA <5,000 IU/ml) 6 months after stopping full-dose initial treatment.

METHODS

We identified 120 consecutive naïve patients over 4 years treated with pegylated interferon alpha-2a and ribavirin with full-dose therapy for 24 weeks (non-genotype 1) or 48 weeks (genotype 1) with baseline liver biopsy and at least 6 months of follow-up after treatment. HCV RNA by PCR and hepatic blood tests were obtained monthly during treatment and at least 1, 3, and 6 months post treatment.

RESULTS

Of the initially treated patients, 54.2% had SVR, 25% non-response and 20.8% relapsed. Four of 25 who relapsed (16%) and one similar patient referred to our program had HCV RNA <5,000 IU/ml 6 months after stopping treatment (VLVL relapse). Significant differences (P < 0.05) compared with the 21 other relapse patients included all five patients who were genotype 1; 4/5 had cirrhosis, baseline HCV RNA was lower, and all had SVR to less intensive re-treatment for 6 months.

CONCLUSION

VLVL relapse patients should be sought, because SVR to re-treatment is common despite genotype 1 cirrhosis.

S-adenosyl methionine improves early viral responses and interferon-stimulated gene induction in hepatitis C nonresponders

BACKGROUND & AIMS

Less than half of patients infected with hepatitis C virus (HCV) achieve sustained viral clearance after pegylated interferon (peginterferon) and ribavirin therapy. S-adenosyl methionine (SAMe) improves interferon signaling in cell culture. We assessed the effect of SAMe on the kinetics of the early antiviral response and interferon signaling in nonresponders to previous antiviral therapy and investigated the mechanisms involved.

METHODS

Nonresponders with HCV genotype 1 were given peginterferon alfa-2a and ribavirin for 2 weeks (course A, baseline/control). After 1 month, patients received SAMe (1600 mg daily) for 2 weeks and then peginterferon and ribavirin for 48 weeks (course B; completed by 21 of 24 patients). Viral kinetics and interferon-stimulated gene (ISG) expression in peripheral blood mononuclear cells (PBMCs) were compared between courses.

RESULTS

The decrease in HCV RNA from 0 to 48 hours (phase 1) was similar with and without SAMe. However, the second phase slope of viral decline was improved with SAMe (course A, 0.11 ± 0.04 log(10) IU/mL/wk; course B, 0.27 ± 0.06; P = .009); 11 patients (53%) achieved an early virological response, and 10 (48%) had undetectable HCV RNA by week 24. Induction of ISGs in PBMCs was significantly greater during course B. In cultured cells, SAMe increased induction of ISGs and the antiviral effects of interferon by increasing STAT1 methylation, possibly affecting STAT1-DNA binding.

CONCLUSIONS

The addition of SAMe to peginterferon and ribavirin improves the early viral kinetics and increases ISG induction in nonresponders to previous therapy. SAMe might be a useful adjunct to peginterferon-based therapies in chronic HCV infection.