Hepatitis C minimal residual viremia (MRV) detected by TMA at the end of Peg-IFN plus ribavirin therapy predicts post-treatment relapse

Impact of antiviral therapy on hepatocellular carcinoma and mortality in patients with chronic hepatitis C: systematic review and meta-analysis

Background

The long-term clinical outcomes of antiviral therapy for patients with chronic hepatitis C are uncertain in terms of hepatitis C virus (HCV)-related morbidity and mortality according to the response to antiviral therapy. This study aimed to assess the impact of antiviral treatment on the development of HCC and mortality in patients with chronic HCV infection.

Methods

A systematic review was conducted for studies that evaluated the antiviral efficacy for patients with chronic hepatitis C or assessed the development of HCC or mortality between SVR (sustained virologic response) and non-SVR patients. The methodological quality of the enrolled publications was evaluated using Risk of Bias table or Newcastle-Ottawa scale. Random-effect model meta-analyses and meta-regression were performed. Publication bias was assessed.

Results

In total, 59 studies (4 RCTs, 15 prospective and 40 retrospective cohort studies) were included. Antiviral treatment was associated with reduced development of HCC (vs. no treatment; OR 0.392, 95% CI 0.275–0.557), and this effect was intensified when SVR was achieved (vs. no SVR, OR: 0.203, 95% CI 0.164–0.251). Antiviral treatment was associated with lower all-cause mortality (vs. no treatment; OR 0.380, 95% CI 0.295–0.489) and liver-specific mortality (OR 0.363, 95% CI 0.260–0.508). This rate was also intensified when SVR was achieved [all-cause mortality (vs. no SVR, OR 0.255, 95% CI 0.199–0.326), liver-specific mortality (OR 0.126, 95% CI 0.094–0.169)]. Sensitivity analyses revealed robust results, and a small study effect was minimal.

Conclusions

In patients with chronic hepatitis C, antiviral therapy can reduce the development of HCC and mortality, especially when SVR is achieved.

Electronic supplementary material

The online version of this article (doi:10.1186/s12876-017-0606-9) contains supplementary material, which is available to authorized users.

Clinical efficacy of the highly sensitive hepatitis C virus RNA quantitative assay in patients with relapse following interferon-based therapy with second-generation direct-acting antivirals

For refractory chronic hepatitis C, interferon (IFN)-based triple-agent combination therapy with second-generation direct-acting antivirals (DAAs) has been established as the standard treatment method. The rate of decrease in the viral load and the negative conversion of hepatitis C virus (HCV) RNA in the early phase following treatment initiation are considered important factors for predicting the therapeutic outcome. In the present study, the Roche Cobas AmpliPrep/COBAS TaqMan (CAP/CTM) HCV v2.0 assay and the AccuGENE m-HCV RNA quantitative assay [Abbott RealTime HCV (ART) assay] were analyzed for their clinical efficacy and ability to predict therapeutic outcomes in the early phase in patients with relapse following IFN-based second-generation DAA therapy. Of the 56 patients who received IFN-based second-generation DAA therapy since December 2013, 6 achieved an end-of-treatment response (ETR), but subsequently experienced relapse. In these 6 patients, fluctuations in viral loads in the early phase detected by the CAP/CTM and ART assays were compared. At 4 weeks after treatment initiation, 4 of the 6 patients were diagnosed as negative by the CAP/CTM assay, whereas 2 of these 4 patients were not identified as negative by the ART assay. Of the 2 patients, one was signal-positive with an HCV RNA load <1.08 Log IU/ml, and the other patient had a viral load of 1.12 Log IU/ml. At 8 weeks after treatment initiation, 1 patient was found to be negative by the CAP/CTM assay, but signal-positive with a viral load <1.08 Log IU/ml by the ART assay. From 4 to 8 weeks after treatment initiation, 3 of the 6 patients appeared to be discrepant cases. In conclusion, of the 6 patients who achieved an ETR, 4 were determined to have achieved a rapid virological response (RVR) by the CAP/CTM assay, but may not have actually become negative. The ART assay is highly sensitive, has a wide measurement range, may be suitable for monitoring HCV RNA loads, and is expected to have an important role in providing a predictive marker for early therapeutic outcomes. In discrepant cases in which no RVR is proved by either assay, it was assumed important to consider continuation of treatment and to attempt to achieve a sustained virological response.

Clinical significance of discordant positive hepatitis C virus transcription-mediated amplification following end of treatment response

BACKGROUND

Polymerase chain reaction (PCR) assays are the standard for detecting hepatitis C virus viremia. The transcription-mediated amplification (TMA)-based assay is more sensitive.

METHODS

We retrospectively reviewed the charts of patients with a post-end of treatment (EOT) PCR-/TMA+ result to assess the clinical significance of a positive TMA result after a PCR negative EOT response or sustained viral response (SVR). Patients were divided into Group 1: PCR-/TMA+ after EOT response but during 24 week follow-up (n = 4); and Group 2: PCR-/TMA+ after SVR (n = 11).

RESULTS

All Group 1 patients achieved SVR. No Group 2 patients became PCR positive or had a rise in ALT. The TMA subsequently became negative in 6/7 patients with follow-up evaluation.

CONCLUSIONS

A discordant positive TMA post-EOT response or SVR did not seem to be clinically significant. This finding supports the possibility that patients with SVR have an acquired immune surveillance that prevents low-level viremia from progressing to clinical relapse.

Discordance between HCV RNA assays for week 24 HCV RNA determination during pegylated interferon-α/ribavirin treatment for chronic hepatitis C

BACKGROUND

The development of more sensitive HCV RNA assays might necessitate re-evaluation of the rules for stopping treatment (for example, HCV RNA negativity at week 24 during treatment with pegylated interferon-α and ribavirin for chronic hepatitis C). The aim of this study was to assess discordance between the week 24 HCV RNA test results of two PCR-based assays (Amplicor and TaqMan) and the transcription-mediated amplification (TMA) HCV RNA qualitative assay.

METHODS

A total of 89 week 24 samples that were negative using PCR-based assays during treatment were retested with the TMA qualitative assay to investigate discordance between tests results. All week 24 samples were HCV RNA negative by Amplicor or by TaqMan.

RESULTS

Of the 89 patients, 46 (52%) achieved sustained virological response (SVR). Viral breakthrough or relapse occurred in 43 patients (48%). All 89 HCV RNA negative week 24 samples were retested with the qualitative TMA assay. Eleven out of 89 samples had detectable HCV RNA (12%). All patients with detectable HCV RNA experienced breakthrough or relapse (negative predictive value 100%). Of the 78 patients with undetectable HCV RNA at week 24 using the TMA assay, 46 achieved SVR. This resulted in a positive predictive value (PPV) of 59% for the TMA assay compared with a PPV of 52% for the PCR-based assays.

CONCLUSIONS

All patients with detectable HCV RNA at week 24 using the TMA assay eventually relapsed. On the basis of these results, the use of this more sensitive HCV RNA assay could lead to the prevention of unnecessary treatment.

Effects of interferon treatment on development and progression of hepatocellular carcinoma in patients with chronic virus infection: a meta-analysis of randomized controlled trials

Available literature on the effects of interferon (IFN) treatment on development and progression of hepatocellular carcinoma (HCC) in patients with chronic virus infection reports controversial results. The primary objective of this meta-analysis was to evaluate the effect of IFN on HCC risk in patients with chronic hepatitis C virus (HCV) or hepatitis B virus (HBV) infection; IFN's efficacy on local tumor progression and survival of advanced HCC patients was also assessed. All randomized controlled trials (RCTs) comparing IFN with no antiviral treatment were selected. Finally, we identified 11 RCTs including 1,772 patients, who met our inclusion criteria to perform this meta-analysis. Our analysis results showed that IFN significantly decreased the overall HCC incidence in HCV-infected patients [relative risk (RR)=0.39; 95% confidence interval (CI)=0.26-0.59; p=0.000], subgroup analysis indicated that IFN decreased HCC incidence in HCV-related cirrhotic patients evidently (RR=0.44; 95% CI=0.28-0.68; p=0.000); but HCC incidence in nonresponders to initial antiviral therapy did not reduce by maintenance IFN therapy (RR=0.96; 95% CI=0.59-1.56; p=0.864). Analysis results also demonstrated that IFN did not significantly affect the overall rate of HCC in HBV-infected patients although there was a trend favoring IFN therapy (RR=0.23; 95% CI=0.05-1.04; p=0.056). Besides, IFN did not improve one-year overall survival of advanced HCC patients significantly (RR=1.61; 95% CI=0.96-2.69; p=0.072); however, a quantitative analysis on local tumor progression could not be performed owing to lack of unified definitions among trials included in our study. By this meta-analysis, we conclude that IFN therapy is effective in reducing overall HCC risk in chronic HCV-infected patients; using it in this subpopulation seems promising, but its administration in other subpopulations still requires further exploration.

Twelve weeks posttreatment follow-up is as relevant as 24 weeks to determine the sustained virologic response in patients with hepatitis C virus receiving pegylated interferon and ribavirin

A sustained virologic response (SVR) in patients with chronic hepatitis C receiving pegylated interferon (PEG-IFN) plus ribavirin is defined as undetectable serum HCV-RNA at 24 weeks (W+24) posttreatment follow-up. Viral load outcome in patients with virological relapse (VR) has not been explored. This study evaluated whether the assessment of serum HCV-RNA 12 weeks (W+12) after the end of treatment was as relevant as W+24 to evaluate SVR in 573 patients who received combination PEG-IFN and ribavirin and had a virological response at the end of treatment. Serum HCV-RNA was measured, using a new assay based on transcription-mediated amplification (TMA) with a lowest detection limit of 5-10 IU/mL, at W+12 and W+24 after the end of treatment. VR was defined as reappearance of detectable HCV-RNA at W+24 posttreatment follow-up. The positive predictive value (PPV) of undetectable serum HCV-RNA at W+12 was evaluated to identify patients with SVR, and the viral load outcome was measured in relapse patients. At the W+24 posttreatment follow-up, 408 (71%) patients had an SVR, 181 (71.2%) were treated with PEG-IFNalpha-2a and ribavirin, and 227 (71.1%) were treated with PEG-IFNalpha-2b and ribavirin. At W+12, serum HCV-RNA was undetectable in 409 patients, and 408 patients were SVR (PPV 99.7%, 95% confidence interval 99.1-100). In relapse patients, serum HCV-RNA levels were 5.623 +/- 0.748, 4.979 +/- 0.870, and 5.216 +/- 0.758 log(10) IU/mL at baseline, W+12, and W+24, respectively.

CONCLUSION

Our results show that the assessment of serum HCV-RNA 12 weeks after the end of treatment, using the highly sensitive TMA assay (PPV 99.7%), is as relevant as after 24 weeks to predict SVR and make decisions on the management of treated patients, suggesting a new definition for SVR.

Antiviral therapy reduces risk of hepatocellular carcinoma in patients with hepatitis C virus-related cirrhosis

BACKGROUND & AIMS

The effects of antiviral therapy on prevention of hepatocellular carcinoma (HCC) in patients with hepatitis C virus (HCV)-related cirrhosis are unclear. We performed a systematic review and meta-analysis to assess HCC risk reduction in patients with HCV-related cirrhosis who have received antiviral therapy.

METHODS

Twenty studies (4700 patients) were analyzed that compared untreated patients with those given interferon (IFN) alone or ribavirin. Risk ratios (RRs) determined effect size using a random effects model.

RESULTS

Pooled data showed reduced HCC risk in the treatment group (RR, 0.43; 95% confidence interval [CI], 0.33-0.56), although the data were heterogenous (chi(2) = 59.10). Meta-regression analysis showed that studies with follow-up durations of more than 5 years contributed to heterogeneity. Analysis of 14 studies (n = 3310) reporting sustained virologic response (SVR) rates with antiviral treatment showed reduced HCC risk in patients with an SVR, compared with nonresponders (RR, 0.35; 95% CI, 0.26-0.46); the maximum benefits were observed in patients treated with ribavirin-based regimens (RR, 0.25; 95% CI, 0.14-0.46). Meta-analysis of 4 studies assessing the role of maintenance IFN in nonresponders did not show HCC risk reduction (RR, 0.58; 95% CI, 0.33-1.03). No publication bias was detected by the Egger test analysis (P > 0.1).

CONCLUSIONS

The risk of HCC is reduced among patients with HCV who achieve an SVR with antiviral therapy. Maintenance therapy with IFN does not reduce HCC risk among patients who do not respond to initial therapy. View this article's video abstract atwww.cghjournal.org.

Clinical performances of two real-time PCR assays and bDNA/TMA to early monitor treatment outcome in patients with chronic hepatitis C

BACKGROUND

Early viral monitoring is essential for the management of treatment outcome in patients with chronic hepatitis C. A variety of commercially available assays are now available to quantify HCV-RNA in routine clinical practice.

OBJECTIVES

Compare the clinical results of 3 commercially available assays to evaluate the positive predictive value (PPV) and the negative predictive value (NPV) of rapid virological response (RVR) at week 4 and early virological response (EVR) at week 12.

STUDY DESIGN

287 patients treated with standard care regimen combination therapy were studied. HCV-RNA values measured at baseline, week 4, week 12 with VERSANT HCV 3.0 Assay (bDNA), and VERSANT HCV-RNA Qualitative Assay (TMA) (bDNA/TMA); COBAS Ampliprep/COBAS/TaqMan (CAP/CTM) and Abbott m2000sp extraction/m2000rt amplification system (ART). RVR was defined as undetectable serum HCV-RNA and EVR as a > OR =2 log decline in baseline viral load (BLV).

RESULTS

Median (range) BVLs were: 5.585(2.585-6.816), 5.189(2.792-7.747) and 4.804(2.380-6.580) log(10)IU/ml, with bDNA/TMA, CAP/CTM and ART, respectively (p<0.01); RVR was observed in 22%, 30% and 27% of the patients and PPVs were 97%, 91% and 94% with bDNA/TMA, CAP/CTM and ART, respectively (p=0.317). EVR was observed in 76%, 73% and 67% of the patients and NPVs were 93%, 83% and 79% with bDNA/TMA, CAP/CTM and ART, respectively (p=0.09).

CONCLUSIONS

Treatment monitoring should include both detection of serum HCV-RNA at week 4 to predict SVR and at week 12 to predict non-SVR. The value of all 3 assays was similar for evaluating RVR or EVR. Because of viral load discrepancies the same assay should be used throughout patient treatment follow-up.

Virological response at 4 weeks to predict outcome of hepatitis C treatment with pegylated interferon and ribavirin

Background

Viral kinetics during therapy provides information on how to individualize treatment. To determine the benefit of assessing positive predictive values (PPVs) and negative predictive values (NPVs) of rapid virological responses (RVRs) and early virological responses (EVRs), on-treatment outcomes in chronic hepatitis C patients were examined.

Methods

A total of 408 patients (221 treatment-naive) treated with pegylated interferon-α2b and ribavirin were included. Hepatitis C virus (HCV) RNA was measured at baseline, 4 weeks and 12 weeks. RVR was defined as undetectable HCV RNA at 4 weeks and EVR as ≥2 log10 decrease in HCV RNA at 12 weeks. The additive value of RVR on predicting sustained virological response (SVR) was assessed with receiver operating characteristic (ROC) curves.

Results

SVR, RVR and EVR were observed in 46%, 23% and 78% of patients, respectively. PPVs of RVR were 96%, 100% and 100% in treatment-naive patients, relapsers and non-responders, respectively. NPVs of failure to achieve EVR were 97%, 75% and 91%, in treatment- naive patients, relapsers and non-responders, respectively. At 4 weeks, patients with RVR had the highest probability to achieve SVR (odds ratio 44.98 in the entire population and 32.95 in treatment-naive patients). ROC curves showed the area under the ROC curve to be 0.758 versus 0.832 in the entire population and 0.795 versus 0.858 in treatment-naive patients at baseline versus week 4, respectively.

Conclusions

RVR is a strong predictor of SVR (PPV>96%) and failure to achieve EVR is a strong predictor of non-SVR (NPV>75%), independent of patients’ pretreatment status. Added to baseline characteristics, RVR increased the accuracy to predict SVR. The combination of RVR and EVR provided complementary information, and thus provides a key opportunity to individualize treatment and improve the benefit/risk ratio of therapy.

Elevations in alanine aminotransferase levels late in the course of antiviral therapy in hepatitis C virus RNA-negative patients are associated with virological relapse

The incidence and clinical meaning of elevated alanine aminotransferase (ALT) in chronic hepatitis C patients who are hepatitis C virus (HCV)-RNA negative during pegylated interferon (PEG-IFN) and ribavirin therapy have not been completely characterized. In this study our aim was to assess the incidence, pattern, predictive factors, and clinical meaning of elevated ALT in a cohort of 173 chronic hepatitis C patients who obtained viral clearance during either PEG-IFNalpha2(a) or alpha2(b) and weight-based ribavirin therapy. Patients were defined sustained viral responders (SVRs) or relapser responders (RRs) on the basis of a serum HCV-RNA result at 24-week follow-up. SVR and RR were obtained in 141 (58%) and 32 patients (13%), respectively. Among the 173 study patients, 57 patients (33%) had undetectable serum HCV-RNA and elevated ALT in at least one evaluation (weeks 2, 4, 12, 24 in all genotypes, and week 48 in HCV genotype 1 and 4 alone), and this phenomenon was not differently distributed between SVRs and RRs. No pretreatment demographic (age, gender), clinical (ALT levels, histological grade and stage, body mass index) and viral (load, genotype) parameter was associated with this phenomenon. The incidence of elevated ALT levels was not associated with type of PEG-IFN and ribavirin dose. Elevated ALT levels showed a different longitudinal pattern, occurring more frequently between week 12 and the end of treatment in RR as compared to SVR patients (90% versus 9%, P = 0.000001).

CONCLUSION

The occurrence of elevated ALT levels in HCV-RNA-negative patients during PEG-IFN and ribavirin therapy is a fairly frequent and unpredictable phenomenon. Although ALT elevation per se is not associated with a greater risk of relapse, its occurrence in the later phases of therapy is more common in relapsing patients.

The pattern of pegylated interferon-α2b and ribavirin treatment failure in cirrhotic patients depends on hepatitis C virus genotype

Background

Failure of anti-hepatitis C therapy encompasses both primary non-response and post-treatment relapse. Treatment failure to pegylated interferon (PEG-IFN)-α2b and ribavirin (RBV) largely depends upon virus genotype, but the interaction between genotype, cirrhosis and pattern of treatment failure is unclear. We aimed to assess whether cirrhosis modifies the pattern of PEG-IFN-α2b and RBV treatment failure.

Methods

A total of 471 treatment-naive patients with histologically proven chronic hepatitis C virus (HCV) infection (106 with cirrhosis; 185 with HCV genotype 1 [HCV-1], 157 with HCV genotype 2 [HCV-2], 92 with HCV genotype 3 [HCV-3] and 37 with HCV genotype 4 [HCV-4]) were consecutively treated with PEG-IFN-α2b 1.5 μg weekly and weight-based RBV.

Results

The sustained virological response (SVR) rates were 31% in HCV-1 and HCV-4, 80% in HCV-2 and 72% in HCV-3, and were lower in cirrhotic than in non-cirrhotic HCV-1 and HCV-4 (17% versus 36%; P=0.01), and HCV-3 (33% versus 79%; P=0.001), but not HCV-2 (69% versus 83%; P=0.1) patients. Treatment failure was the consequence of lower end-of-treatment response rates (37% versus 53%; P=0.06) plus higher post-treatment relapse rates (55% versus 31%; P=0.07) in cirrhotic HCV-1 and HCV-4 patients and higher rates of post-treatment relapse in HCV-2 (29% versus 10%; P=0.01) and HCV-3 cirrhotic patients (61% versus 12%; P<0.001). By multi-variate analysis, HCV-1 and HCV-4 (odds ratio [OR] 7.44, 95% confidence interval [CI] 4.87–11.36), and cirrhosis (OR 3.00, 95% CI 1.80–5.00) were independent predictors of treatment failure.

Conclusions

Cirrhosis is an important moderator of SVR, accounting for different patterns of treatment failure in patients infected with different genotypes.

Sustained virological response is associated with clearance of hepatitis C virus RNA and a decrease in hepatitis C virus antibody

BACKGROUND/AIM

Viral eradication in chronic hepatitis C patients with sustained virological response (SVR) after interferon (IFN) therapy remains controversial.

METHODS

During a long-term follow-up study, 157 patients with SVR to IFN-alpha-2b-based therapy were investigated with a transcription-mediated amplification (TMA) assay in serum. The hepatitis C virus (HCV) antibody was assessed by measuring the optical density (OD) (Axsym HCV v3.0) and the semiquantitative titres (RIBA HCV v3.0) of the HCV antibodies directed against the core, NS3, NS4 and NS5 proteins. A control group included 23 untreated patients with persistently normal serum alanine aminotransferase and detectable serum HCV-RNA.

RESULTS

The median duration of follow-up was 4.0 (0-10) years. Serum HCV-RNA remained undetectable in all patients. The mean HCV antibody OD were 93 +/- 19 and 45 +/- 21 before therapy and in the last available serum sample respectively (P=0.001). There was a marked decrease in the HCV antibodies directed against the NS3, NS4 and NS5 proteins (P=0.001), while the core protein titre remained strongly positive. The 23 control patients were followed for a median of 5 (2-14) years. The mean HCV antibody OD were 65 +/- 14 and 64 +/- 19 in the first and the last measurements, respectively (NS), and HCV antibody titres for structural and non-structural proteins remained unchanged.

CONCLUSION

This long-term study evaluating 157 patients demonstrated that SVR assessed by TMA is durable, and HCV antibodies were markedly decreased (mainly those directed against the non-structural proteins), emphasizing an absence of ongoing infection. These results strongly suggest that HCV infection cured in patients who achieve an SVR.

Virological relapse in chronic hepatitis C

Approximately one-third of all patients infected with hepatitis C virus (HCV) genotype 1 who complete pegylated interferon α-based therapy and have undetectable serum HCV RNA at the end of treatment will experience relapse. Although relapse is a common outcome of therapy, its pathology and strategies for optimal management are poorly understood; however, optimized ribavirin dosing is recognized as pivotal in mitigating relapse. Recent data also suggest that early viral kinetics might help identify particular patient groups, such as slow responders, who are predisposed to relapse. This review provides a comprehensive overview of the importance of relapse in patients with chronic hepatitis C, including its underlying pathobiology, potential predictors and strategies to optimize the retreatment of previous relapsers.

Abbott RealTime hepatitis C virus (HCV) and Roche Cobas AmpliPrep/Cobas TaqMan HCV assays for prediction of sustained virological response to pegylated interferon and ribavirin in chronic hepatitis C patients

Two commercial real-time PCR assays are currently available for sensitive hepatitis C virus (HCV) RNA quantification: the Abbott RealTime HCV assay (ART) and Roche Cobas AmpliPrep/Cobas TaqMan HCV assay (CAP/CTM). We assessed whether the two real-time PCR assays were more effective than Roche Cobas Amplicor HCV Monitor test, v.2.0 (CAM) for prediction of the sustained virological response (SVR) to pegylated interferon (PEG-IFN) plus ribavirin (RBV) in chronic hepatitis C. Sixty patients chronically infected with HCV genotype 1b (37 males and 23 females, 53 +/- 12 years of age) were treated with PEG-IFNalpha2b plus RBV for 48 weeks. Stored specimens at nine time points for each patient (at baseline, on treatment, and 24 weeks after treatment) were tested by the two real-time PCR assays and CAM. Twenty-six (43.3%) patients reached SVR. The positive predictive values (PPVs) for SVR of undetectable HCV RNA at week 12 by CAM, ART, and CAP/CTM were 74.3%, 88.0%, and 95.2%, respectively. An undetectable HCV RNA level by CAM, ART, and CAP/CTM correctly predicted SVR at week 4 in 100%, 100%, and 100% of patients, at weeks 5 to 8 in 91.7%, 100%, and 100% of patients, at weeks 9 to 12 in 55.6%, 75%, and 87.5% of patients, and at weeks 13 to 24 in 0%, 26.7%, and 40% of patients, respectively. Of 16 patients who relapsed after treatment, HCV RNA was detectable in 2 patients at the end of treatment by CAP/CTM but undetectable by ART and CAM. HCV RNA tests using ART and CAP/CTM are considered to be more effective at predicting SVR than CAM, and the PPV for SVR was slightly higher in CAP/CTM than in ART.

Robust antiviral efficacy upon administration of a nucleoside analog to hepatitis C virus-infected chimpanzees

Hepatitis C virus (HCV) infects an estimated 170 million individuals worldwide and is associated with an increased incidence of liver fibrosis, cirrhosis, and hepatocellular carcinoma. Currently approved therapies to treat HCV infection consist of combinations of pegylated alpha interferon and ribavirin which result in a sustained viral response in 40 to 60% of patients. Efforts to develop improved therapies include the development of direct inhibitors of virally encoded enzymes such as the viral RNA-dependent RNA polymerase. A nucleoside analog, 2'-C-methyl-7-deaza-adenosine (MK-0608), has been shown to inhibit viral RNA replication in the subgenomic HCV genotype 1b replicon, with a 50% effective concentration (EC(50)) of 0.3 microM (EC(90) = 1.3 microM). To determine efficacy in vivo, MK-0608 was administered to HCV-infected chimpanzees, resulting in dose- and time-dependent decreases in plasma viral loads. In separate experiments, chimpanzees dosed for 7 days with MK-0608 at 0.2 and 2 mg per kg of body weight per day by intravenous administration experienced average reductions in viral load of 1.0 and >5 log(10) IU/ml, respectively. Two other HCV-infected chimpanzees received daily doses of 1 mg MK-0608 per kg via oral administration. After 37 days of oral dosing, one chimpanzee with a high starting viral load experienced a reduction in viral load of 4.6 log(10), and the viral load in the other chimpanzee fell below the limit of quantification (LOQ) of the HCV TaqMan assay (20 IU/ml). Importantly, viral load remained below the LOQ throughout the duration of dosing and for at least 12 days after dosing ended. The results demonstrate a robust antiviral effect on the administration of MK-0608 to HCV-infected chimpanzees.

Interpretation of positive transcription-mediated amplification test results from polymerase chain reaction-negative samples obtained after treatment of chronic hepatitis C

The Siemens VERSANT transcription-mediated amplification (TMA) assay is extremely sensitive for the detection of hepatitis C virus (HCV) RNA in serum. Eleven of 180 subjects in the Hepatitis C Antiviral Long-term Treatment against Cirrhosis (HALT-C) Trial who achieved polymerase chain reaction (PCR)-defined sustained virological response (SVR) at week 72 also had TMA-positive results from the same blood draw; six were positive on repeat testing. We report the follow-up on these 11 patients, and the reproducibility of TMA test results from PCR-negative samples in relationship to antiviral treatment outcome. Peginterferon and ribavirin treatment was initiated in 1145 prior interferon nonresponders with advanced hepatic fibrosis. Treatment was continued for 48 weeks if patients had undetectable HCV RNA by PCR at treatment week 20. Frozen serum samples from weeks 12, 20, 24, 48, and 72 were subsequently tested by TMA. Nine of the 11 patients returned for testing (median, 30 months after the week 72 visit), and all had undetectable HCV RNA by TMA and PCR. Among 759 PCR-negative samples obtained during treatment that were tested twice by TMA, 17% overall exhibited consistently positive results, and 21% exhibited inconsistently positive results. SVR was more likely if TMA was consistently negative than if consistently or inconsistently positive. With continued treatment, patients with inconsistently positive TMA results were more likely to become TMA-negative than TMA-positive (P < 0.0001).

CONCLUSION

In PCR-negative samples, positive TMA results may indicate the presence of low levels of HCV RNA. However, because patients with positive TMA results may achieve SVR, management decisions during therapy should not be based on a single positive TMA test result.

Eradication of hepatitis C virus in patients successfully treated for chronic hepatitis C

BACKGROUND & AIMS

It is unclear whether hepatitis C virus (HCV) is eradicated in patients with chronic hepatitis C who achieved a sustained virologic response (SVR).

METHODS

In this long-term follow-up study, including chronic hepatitis C patients who achieved SVR after interferon-based therapy, the presence of residual HCV RNA in serum, liver, and peripheral blood mononuclear cells (PBMCs) was assessed, using transcription-mediated amplification (sensitivity, <9.6 IU/mL). The benefit of SVR on liver fibrosis was evaluated using the METAVIR score.

RESULTS

A total of 344 patients were followed up for a median duration of 3.27 years (range, 0.50-18 y; interquartile range [IQR], 1.68-5.35 y). A total of 114 patients had a posttreatment liver tissue (median, 0.50 y; range, 0-14 y; IQR, 0-3.5 y) and a total of 156 had one PBMC (median, 3.0 y; range, 0.50-18 y; IQR, 1.25-5.50 y). Serum HCV RNA remained undetectable (1300 samples), indicating that none of the patients had a relapse. HCV RNA was detectable in 2 of 114 (1.7%) liver specimens, and in none of 156 PBMC specimens. Histologic analysis of 126 paired pretreatment and posttreatment liver biopsy specimens (median, 0.50 y; range, 0-14 y; IQR, 0-3.5 y) showed that fibrosis stage was improved in 56%, stable in 32%, deteriorated in 12%. Regression of cirrhosis was observed in 9 of 14 (64%) (95% confidence interval, 39-89) patients. No cirrhosis decompensation was observed, and 3 patients developed hepatocellular carcinoma.

CONCLUSIONS

In this large cohort of chronic hepatitis C patients, SVR was durable up to 18 years after treatment cessation, in addition to fibrosis stability/improvement (88%) and cirrhosis regression (64%). The presence of residual HCV RNA was observed only in liver tissue (1.7%). This result strongly suggests that SVR may be considered to show eradication of HCV infection.

The use of molecular assays in the management of viral hepatitis

Molecular assays are instrumental in the clinical management of viral hepatitis. During the past years, a wide variety of molecular assays have been developed and implemented. This considerably improved the understanding of the natural history and pathogenesis of Hepatitis B virus (HBV), Hepatitis C virus (HCV) or Hepatitis delta virus (HDV) hepatitis, but also caused uncertainties in the selection of the most appropriate assays for clinical requirements. Indeed, a rational choice and application of these assays requires adequate knowledge of the performance of the single test. Moreover, the choice of the most accurate assay for patients' needs and physicians' objectives, needs to be oriented to specific contexts, such as diagnosis, management or treatment. In the past, a hurdle in the routine use of assays for hepatitis viruses nucleic acid quantification was represented by the availability of only "home brew" methods which lacked standardization. Major improvement in addressing the use of molecular assays for viral hepatitis has been derived from recent standardization procedures that allowed a comparison between different tests after results were given as International Units. In addition, it should be reminded that, before getting into the market, molecular assays should be approved by European regulation authorities and validated using internationally recognized standards. A subsequent clinical validation should address the diagnostic accuracy of the assay. These proceedings have the aim of identifying which molecular tests, among those currently available, meet clinical requirements for each specific application.

Clinical evaluation of the COBAS Ampliprep/COBAS TaqMan for HCV RNA quantitation in comparison with the branched-DNA assay

Diagnosis and monitoring of HCV infection relies on sensitive and accurate HCV RNA detection and quantitation. The performance of the COBAS AmpliPrep/COBAS TaqMan 48 (CAP/CTM) (Roche, Branchburg, NJ), a fully automated, real-time PCR HCV RNA quantitative test was assessed and compared with the branched-DNA (bDNA) assay. Clinical evaluation on 576 specimens obtained from patients with chronic hepatitis C showed a good correlation (r = 0.893) between the two test, but the CAP/CTM scored higher HCV RNA titers than the bDNA across all viral genotypes. The mean bDNA versus CAP/CTM log10 IU/ml differences were -0.49, -0.4, -0.54, -0.26 for genotype 1a, 1b, 2a/2c, 3a, and 4, respectively. These differences reached statistical significance for genotypes 1b, 2a/c, and 3a. The ability of the CAP/CTM to monitor patients undergoing antiviral therapy and correctly identify the weeks 4 and 12 rapid and early virological responses was confirmed. The broader dynamic range of the CAP/CTM compared with the bDNA allowed for a better definition of viral kinetics. In conclusion, the CAP/CTM appears as a reliable and user-friendly assay to monitor HCV viremia during treatment of patients with chronic hepatitis. Its high sensitivity and wide dynamic range may help a better definition of viral load changes during antiviral therapy.

The course of hepatitis C viraemia in transfusion recipients prior to availability of antiviral therapy

Knowing the likely distribution of intervals from hepatitis C infection to first RNA-negativity is important in deciding about therapeutic intervention. Prospectively collected sera and data from the Transfusion-transmitted Viruses Study (1974-1980) provide specific dates of infection and pattern of alanine aminotransferase (ALT) elevations. We examined frequency, timing and correlates of spontaneous resolution for 94 acutely infected transfusion recipients followed for a median of 9.5 months. Later, follow-up sera (>10 years) were available for 27 of the 94 cases from a Veterans Administration (VA) Study (1989-1990). Twenty-five (27%) of the 94 cases were classified as probably resolved during the episode itself. First RNA negativity occurred at 6-50 weeks (median, 19.5 weeks) after infection, and 5-43 weeks (median, 11 weeks) after ALT elevation. Thirteen of the 25 cases remained RNA-negative subsequently; 12 others had 1-6 RNA-positive sera intercalated between first and last RNA-negative results. RNA negativity, therefore, began variably and was interrupted in 12 cases of 25 (48%) by transient RNA-positive sera. Five of these 25 patients who were RNA-negative in the last study specimen had late, Veterans Administration Study follow-up; none showed viraemia. Of the remaining 69 transfusion transmitted virus study recipients, whose last serum was RNA-positive, two cleared viraemia after the last study serum but before late follow-up. Eleven (16%) had 23 intercalated RNA-negative sera before last positivity. RNA status, therefore, needs monitoring for many months before judging the spontaneous outcome as transient negativity may occur. Resolution was significantly more common in women and symptomatic cases; it was not associated with viral load in the infectious donation, HCV genotype, or the recipient's age.

Assessment of hepatitis C virus-RNA clearance under combination therapy for hepatitis C virus genotype 1: performance of the transcription-mediated amplification assay

Monitoring of HCV-RNA in blood during antiviral therapy is performed mostly by commercially available reverse transcription polymerase chain reaction-based (RT-PCR) assays, with a lower detection limit of 30-50 IU/mL of HCV-RNA. Use of different tests in the pivotal trials of combination therapy has generated some discordance, in terms of predictive value of the early virological response (EVR). To evaluate whether the use of a more sensitive test, as a qualitative assay based on transcription mediated amplification (TMA) with a lower detection limit of 5-10 IU/mL of HCV-RNA, may obtain a better prediction of EVR and of the ultimate virological outcome, we retrospectively evaluated serial samples from 108 naïve patients with HCV genotype 1 chronic hepatitis, treated with pegylated alpha2b interferon plus ribavirin for 48 weeks and with a 24 weeks stopping rule. Serum samples of patients, obtained during treatment at weeks 4, 12, 24 and 48 and after treatment at week 24, were evaluated by TMA. Comparison of the RT-PCR and TMA assays for the qualitative detection of HCV-RNA showed no significant differences in performance when these tests were used at the end of the treatment period for assessing patients without an on-treatment virological response and those who eventually obtain a sustained virological response. Our results show instead that the use of TMA assay to detect HCV-RNA at 12 and 24 weeks of the combination therapy is more effective than RT-PCR in identifying patients with the highest probability of sustained HCV-RNA clearance.

Personalized therapy for chronic viral hepatitis C in the naive patient: How can we optimize treatment duration as a function of viral genotype?

Pegylated interferon plus ribavirin is the standard treatment for chronic hepatitis C (CHC). It yields sustained virological response (SVR) rates of 42-52% for genotype 1, 66-72% for genotype 4, and 76-80% for genotypes 2 and 3. Hence, the patient's genotype appears to be a determining predictive factor for the SVR. We have reviewed the literature in order to determine whether a genotype-specific treatment duration should be envisaged. The largest study to date of patients infected with HCV genotype 2 or 3 confirmed the value of the standard treatment duration of 24 weeks. Shorter treatments exposed the patients to a greater risk of relapse. For genotype 1, it was possible to offer a shorter, 24-week course of treatment to the 35% of patients with an initial viral load below 600,000 IU/mL and an early virological response (EVR) at week 4 (negative PCR), resulting in an SVR of 89%. For the remaining two-thirds of genotype 1 patients with a high viral load, the treatment duration should remain at 48 weeks. A subgroup of patients - the "slow virological responders" (positive PCR at week 12 but with less than 6000 IU/mL; negative PCR at week 24) - benefited from the extension of the treatment to 72 weeks, with an SVR of 88%. For patients infected with genotype 4 virus, combination therapy should feature a ribavirin dose of more than 1000 mg/day for an optimal duration of 48 weeks.

Prognostic significance of hepatitis C virus RNA detection by transcription-mediated amplification with negative polymerase chain reaction during therapy with peginterferon alpha and ribavirin

The lower limit of detection of most polymerase chain reaction (PCR) assays for hepatitis C virus (HCV) RNA is 50 IU/ml, compared to 5 IU/ml for the transcription-mediated amplification (TMA) method. We retrospectively reviewed 57 patients to assess the predictive value of a positive TMA in the setting of a negative PCR during antiviral therapy. Patients were divided into (1) PCR-/TMA+ (discordant; n=21) and (2) PCR-/TMA-(concordant; n=36). Sustained virologic response (SVR) was decreased in the discordant group (48% vs. 75%; P=0.04). In discordant patients, SVR was more frequent in patients who had one positive TMA than in those who had two or more positive TMAs or one positive TMA and recurrent HCV RNA detectability by PCR during treatment (78% vs. 25%; P=0.03). Breakthrough occurred more frequently in discordant patients (24% vs. 3%; P=0.02). A positive TMA on two or more occasions in patients who have become PCR-negative on therapy indicates a high likelihood of treatment failure.

Long-term follow-up of the hepatitis C HENCORE cohort: response to therapy and occurrence of liver-related complications

The aims of the study were to verify the long-term effect of time on viral clearance in hepatitis C virus (HCV) patients and to find out factors possibly associated with disease progression. A total of 1641 patients recruited from eight European centres in 1996-1997 were re-analysed 5-7 years after inclusion. The occurrence of decompensated cirrhosis, hepatocellular carcinoma (HCC) and liver transplantation was analysed in relation to different host and viral factors. Ninety-three per cent of the HCV patients who had cleared the virus (spontaneously or after antiviral therapy) remained HCV-RNA-negative during follow up and may be considered as 'cured'. Among patients who were sustained responders at inclusion, 2.3% developed liver complications during follow up, and 31% of non-responders did. Advanced age at infection and presence of the human leucocyte antigen (HLA) DRB1*1201-3 allele were possibly associated with a higher rate of progression to decompensated cirrhosis or HCC. Decompensated cirrhosis might be further associated with male gender, non-response to previous therapy, and lack of HLA DRB1*1301 allele, whereas HCC seems to be associated with the presence of the HLA DQ02 allele. Long-term follow up of HCV patients indicates that virological response persists over time and is associated with a very low incidence of liver complications. Advanced age at inclusion, advanced age at infection, viral genotype 1, non-response to previous therapy and possibly some specific HLA alleles are factors independently associated with a faster rate of progression towards liver complications. The large proportion of patients lost to follow up stresses the need for a strengthened and optimized management of HCV patients.

Role of weight-based ribavirin dosing and extended duration of therapy in chronic hepatitis C in HIV-infected patients: the PRESCO trial

The response to pegylated interferon (pegIFN) plus ribavirin (RBV) as treatment of chronic hepatitis C virus (HCV) infection is lower in HIV-coinfected than in HCV-monoinfected patients and could be due to suboptimal RBV dosing and/or insufficient duration of therapy in prior trials. In a prospective, multicenter, open, comparative trial, HCV/HIV-coinfected patients received pegIFN plus weight-based RBV for 48 or 72 weeks (HCV genotypes 1 and 4) and 24 or 48 weeks (HCV genotypes 2 and 3). Use of didanosine was not allowed. Out of 389 patients included in the trial, 61% were infected by HCV-1/4 and 67% had serum HCV-RNA >500,000 IU/ml. Sustained virological response (SVR) was achieved by 49.6%, significantly higher in HCV-2/3 than HCV-1/4 (72.4% vs. 35%; p < 0.0001). A high drop-out rate in the longer treatment arms precluded obtaining definitive conclusions about the efficacy of prolonging therapy. Premature treatment discontinuations due to serious adverse events occurred in 8.2%. Infection with HCV-2/3, lower baseline HCV-RNA, and negative HCV-RNA at week 12 were all independent predictors of SVR in the multivariate analysis. The use of RBV 1000-1200 mg/day plus pegIFN is relatively safe and provides SVR in nearly half of coinfected patients, twice as high in HCV-2/3 than HCV-1/4.

Involvement of dendritic cell frequency and function in virological relapse in pegylated interferon-alpha and ribavirin therapy for chronic hepatitis C patients

A combination of pegylated interferon alpha (PEG-IFNalpha) and ribavirin has been used widely. Enhancement of immune response against hepatitis C virus (HCV) is known to be involved in the efficacy of the combination therapy. The aim of the study was to elucidate whether the frequency or function of immunocompetent blood cells is related to the outcome of the therapy. Twenty-five chronic hepatitis C patients with high viral load of HCV genotype 1 who underwent 48 weeks of PEG-IFNalpha2b and ribavirin therapy were examined. During the treatment, frequencies of dendritic cell subsets, helper T cell subsets, and NK cells were phenotypically determined. In some patients, the ability of dendritic cells to stimulate allogeneic CD4(+)T cells was examined at the end and after the therapy. Among the 25 patients, 11 showed a sustained virological response, 11 a transient response, and 3 no response. In comparison with sustained virological responders, non-sustained virological responders showed impaired dendritic cell function at the end and after the treatment. The transient responders showed a decline of plasmacytoid dendritic cell frequency from Weeks 1-12 and impaired dendritic cell function as well. Even in patients who attained negative serum HCV RNA at Week 12, the transient responders showed a significant decrease of plasmacytoid dendritic cell frequency and impaired dendritic cell function. In conclusion, in PEG-IFNalpha and ribavirin combination therapy for chronic hepatitis C patients, the early-phase plasmacytoid dendritic cell frequency and/or end-of-treatment dendritic cell function are related to the virological outcome of the therapy.

Sustained virological response to interferon-alpha is associated with improved outcome in HCV-related cirrhosis: a retrospective study

The effect of achieving a sustained virological response (SVR) following interferon-alpha (IFNalpha) treatment on the clinical outcomes of patients with HCV-related cirrhosis is unknown. In an attempt to assess the risk of liver-related complications, HCC and liver-related mortality in patients with cirrhosis according to the response to IFNalpha treatment, a retrospective database was developed including all consecutive patients with HCV-related, histologically proven cirrhosis treated with IFNalpha monotherapy between January 1992 and December 1997. SVR was an undetectable serum HCV-RNA by PCR 24 weeks after IFNalpha discontinuation. HCC was assessed by ultrasound every 6 months. Independent predictors of all outcomes were assessed by Cox regression analysis. Of 920 patients, 124 (13.5%) were classified as achieving a SVR. During a mean follow-up of 96.1 months (range: 6-167) the incidence rates per 100 person-years of liver-related complications, HCC and liver-related death were 0, 0.66, and 0.19 among SVR and 1.88, 2.10, and 1.44 among non-SVR (P<0.001 by log-rank test). Multivariate analyses found that non-SVR was associated with a higher risk of liver-related complications (hazard ratio, HR, not applicable), HCC (HR 2.59; 95% CI 1.13-5.97) and liver-related mortality (HR 6.97; 95% CI 1.71-28.42) as compared to SVR.

CONCLUSION

Thus, in patients with HCV-related, histologically proven cirrhosis, achievement of a SVR after IFNalpha therapy was associated with a reduction of liver-related mortality lowering both the risk of complications and HCC development. Irrespective of SVR achievement, all patients should continue surveillance because the risk of occurrence of HCC was not entirely avoided.

Prediction of the efficacy of antiviral therapy for hepatitis C virus infection by an ultrasensitive RT-PCR assay

The efficacy of interferon therapy for hepatitis C virus (HCV) infection improved remarkably. However, virologic relapse occurs in a substantial proportion of patients with virologic response (defined as an HCV RNA level below 50 IU/ml at the end-of-treatment). A highly sensitive RT-nested PCR assay capable of detecting almost a single copy of HCV RNA and a real-time RT-PCR assay to quantify HCV RNA down to 120 copies per ml were developed. The RT-nested PCR assay showed that 1 IU of HCV RNA is equivalent to 12.2 copies. For 28 patients with virologic response (12 relapsers and 16 sustained virologic responders), week-4 and end-of-treatment plasma samples were retested. At week 4, HCV RNA was detected by the RT-nested PCR and qualitative COBAS Amplicor HCV version 2.0 in 8/9 (89%) and 6/9 (67%) samples from relapsers, and in 4/16 (25%) and 2/16 (13%) samples from sustained virologic responders, respectively. End-of-treatment samples with HCV-negative by the qualitative COBAS Amplicor were positive by the present assay in 4/12 (25%) of relapsing patients and 0/16 (0%) of sustained virologic responders. The viral levels detected by the present assay in the Amplicor-negative samples were 3.5-17.3 copies/ml, which is below the detection limit of COBAS Amplicor. In conclusion, the highly sensitive RT-nested PCR assay can predict sustained virologic response at week 4 and virologic relapse at the end-of-treatment more accurately than COBAS Amplicor, suggesting its usefulness in monitoring antiviral therapy for HCV infection.

Host and viral factors in the immunopathogenesis of primary hepatitis C virus infection

Individuals infected with hepatitis C virus (HCV) have two possible outcomes of infection, clearance or persistent infection. The focus of this review is the host mechanisms that facilitate clearance. The interaction between HCV viral components and the immune system ultimately determines the balance between the virus and host. Strong evidence points to the aspects of cellular immune response as the key determinants of outcome. The recent discovery of viral evasion strategies targeting innate immunity suggests that the interferon-alpha/beta induction pathways are also critical. A growing body of evidence has implicated polymorphisms in both innate and adaptive immune response genes as determinants of viral clearance in individuals infected with HCV.

HCV RNA detection by TMA during the hepatitis C antiviral long-term treatment against cirrhosis (Halt-C) trial

For making treatment decisions related to chronic hepatitis C, the utility of HCV RNA tests with increased sensitivity has not been defined. Prior interferon nonresponders with advanced fibrosis (n = 1,145) were retreated with peginterferon alpha-2a and ribavirin. Patients who were HCV RNA-negative by a polymerase chain reaction (PCR)-based assay (Roche COBAS Amplicor HCV Test, v. 2.0; lower limit of detection [LOD] 100 IU/mL) at week 20 (W20) received treatment for 48 weeks. Stored specimens were tested using the Bayer VERSANT HCV RNA Qualitative (TMA) Assay (LOD 9.6 IU/mL) and compared to PCR results for the ability to predict sustained virological response (SVR; defined as undetectable HCV RNA by PCR at W72). Nearly all PCR-positive samples (1006/1007, 99.9%) were positive as assessed by TMA. Among 1,294 PCR-negative samples, 22% were TMA-positive. Negative TMA results were more predictive of SVR than were negative PCR results at W12 (82% vs. 64%, P < .001) and at W20 (66% vs. 52%, P = 0.001). SVR was more likely the earlier TMA had become negative during treatment (82% at W12, 44% at W20, 20% at W24). Among 45 patients who were TMA-positive but were PCR-negative at W20 and W24, none achieved SVR (95% CI: 0%-8%). Approximately 10% of patients with a single positive TMA result at the end of treatment still achieved SVR. In conclusion, negative TMA results at or after W12 were superior to negative PCR results for predicting SVR. In patients with negative PCR results during treatment, a single positive TMA test did not exclude SVR, although persistently positive tests did.

Impaired Response to Interferon-α2B plus Ribavirin in Cirrhotic Patients with Genotype 3A Hepatitis C Virus Infection

Patients with chronic infection with the 3a genotype of hepatitis C virus (HCV) are considered as ‘easy-to-treat’ with interferon/ribavirin (IFN/RBV), independent of liver disease severity. However, patients with extensive fibrosis or cirrhosis were under-represented in all the registration Phase III trials performed so far. To assess the influence of liver fibrosis on the outcome of anti-HCV therapy, all patients with genotype 3a hepatitis C who were naive to IFN-based therapies, and received RBV combined with standard IFN or pegylated IFN-α2b (peg-IFN-α2b) as standard of care for their disease, were investigated at our centre. A sustained virological response (SVR) was achieved in 68 of 91 patients (75%) independent of IFN type, pretreatment viraemia, clearance of HCV RNA at week 4 and relevant co-morbidities. A SVR was less common in cirrhotics (6 of 17) than in non-cirrhotics (62 of 74; 35% vs 84%; P<0.0005). Compared to non-cirrhotics, the age and sex adjusted odds ratio (OR) of treatment failure for cirrhotics was 10.1 (95% confidence interval: 2.4–41.7). By multivariate analysis, cirrhosis was the only predictor of non-SVR. In conclusion, cirrhosis is an independent predictor of IFN/RBV treatment failure in patients chronically infected with HCV 3a and is associated with an increased risk of post-treatment hepatitis relapse. Evaluation of liver fibrosis is important in the management of patients with genotype 3a hepatitis C, since it helps to predict response to IFN/RBV therapy.