Predictive factors of early and sustained responses to peginterferon plus ribavirin combination therapy in Japanese patients infected with hepatitis C virus genotype 1b: amino acid substitutions in the core region and low-density lipoprotein cholesterol levels

Pretreatment prediction of virological response to peginterferon plus ribavirin therapy in chronic hepatitis C patients using viral and host factors

The interferon sensitivity determining region (ISDR) of the hepatitis C virus (HCV) and T-helper type 1 and type 2 (Th1/Th2) ratio were analyzed along with other host and viral factors for their ability to predict the response of patients with chronic hepatitis C to pegylated interferon alpha-2b (Peg-IFN) and ribavirin (RBV) combination therapy. A total of 120 chronic hepatitis C patients with genotype 1 HCV and high baseline viral loads who were to undergo combination therapy scheduled for 48 weeks were enrolled. Sustained virologic response (SVR) was achieved in 54 (45%) of the 120 patients. The pretreatment factors significantly associated with SVR by logistic regression analysis were ISDR mutant [odds ratio (OR) = 86.0, P = 0.0008], Th1/Th2 ratio </= 15.5 (OR = 9.6, P = 0.0021), body weight 59 kg, and neutrophil count 2,300/microL. A logistic regression model to estimate SVR before combination therapy was constructed using these four factors. Patients fell into three groups when plotted according to estimated and actual SVR rates: actual SVR rate was 91% (32/35) in the high sensitivity group, 41% (15/37) in the intermediate sensitivity group, and 15% (7/48) in the low sensitivity group. Rapid or early virological responses were seen in 80% of patients with high sensitivity and who achieved SVR but were found in only 40% of patients with intermediate or low sensitivity. Null- and very late virological responses were quite rare in the high sensitivity group. In conclusion, a logistic regression model that includes the sequence of ISDR of the HCV, Th1/Th2 ratio, body weight, and neutrophil count can be useful for accurately predicting actual SVR rate before combination therapy.

Efficacy of pegylated interferon plus ribavirin treatment in HIV/hepatitis C virus co-infected patients receiving abacavir plus lamivudine or tenofovir plus either lamivudine or emtricitabine as nucleoside analogue backbone

OBJECTIVES

To compare the response to hepatitis C virus (HCV) therapy among human immunodeficiency virus (HIV)/HCV co-infected patients receiving a nucleos(t)ide reverse transcriptase inhibitor [N(t)RTI] backbone consisting of abacavir plus lamivudine with that observed in subjects who receive tenofovir plus lamivudine or emtricitabine.

METHODS

A total of 256 subjects, enrolled in a cohort of 948 HIV-infected patients who received pegylated interferon and ribavirin from October 2001 to January 2006, were included in this study. All patients were taking one protease inhibitor or one non-nucleoside reverse transcriptase inhibitor and abacavir plus lamivudine or tenofovir plus lamivudine or emtricitabine as N(t)RTI backbone during HCV therapy. Sustained virological response (SVR) rates in both backbone groups were compared.

RESULTS

In an intention-to-treat analysis, 20 out of 70 (29%) individuals under abacavir and 83 out of 186 (45%) under tenofovir showed SVR (P = 0.02). N(t)RTI backbone containing tenofovir was an independent predictor of SVR in the multivariate analysis [adjusted odds ratio (95% CI), 2.6 (1.05-6.9); P = 0.03]. The association between abacavir use and lower SVR was chiefly seen in patients with plasma HCV-RNA load higher than 600 000 IU/mL and genotype 1 or 4. Among patients treated with ribavirin dose <13.2 mg/kg/day, 3 (20%) of those under abacavir versus 22 (52%) under tenofovir reached SVR (P = 0.03), whereas the rates were 31% and 38% (P = 0.4), respectively, in those receiving >/=13.2 mg/kg/day.

CONCLUSIONS

HIV-infected patients who receive abacavir plus lamivudine respond worse to pegylated interferon plus ribavirin than those who are given tenofovir plus lamivudine or emtricitabine as N(t)RTI backbone, especially in those receiving lower ribavirin doses.

Substitution of amino acid 70 in the hepatitis C virus core region of genotype 1b is an important predictor of elevated alpha-fetoprotein in patients without hepatocellular carcinoma

Previous studies identified amino acid (aa) substitutions of the hepatitis C virus core region of genotype 1b (HCV-1b core region) and elevated serum alpha-fetoprotein (AFP) levels as predictors of poor virologic response to pegylated interferon (PEG-IFN) plus ribavirin (RBV), and also as risk factors for hepatocarcinogenesis. The present study evaluated the impact of aa substitutions of HCV-1b core region on AFP, as a surrogate marker of hepatocarcinogenesis, on AFP levels in 569 Japanese patients with HCV-1b but without HCC, and investigated the predictive factors of elevated AFP (> or =11 microg/L). High AFP levels were detected in 27.4% of the patients. The rate of hepatocarcinogenesis in a group of 109 patients who received IFN monotherapy and followed-up for 15 years, was significantly higher in patients with abnormal than normal AFP. Multivariate analysis of 569 patients identified fibrosis stage (F3,4), aspartate aminotransferase (> or =76 IU/L), substitution of aa 70 (glutamine or histidine), and platelet count (<15.0 x 10(4)/microl) as significant determinants of elevated AFP. In 49 patients with abnormal AFP levels and substitutions at aa 70 who were treated with PEG-IFN + RBV, the rate of normalization of AFP was significantly lower in non-virological responders (28.6%) than in transient (71.4%) and sustained (100%) virological responders. The results indicated that substitution of aa 70 of HCV-1b core region is an important predictor of elevated AFP in non-HCC patients, and that eradication of the mutant virus normalizes AFP. The results highlight the importance of eradication of mutant type virus of aa 70 for reducing the risk of hepatocarcinogenesis.

Efficacy of low-dose intermittent interferon-alpha monotherapy in patients infected with hepatitis C virus genotype 1b who were predicted or failed to respond to pegylated interferon plus ribavirin combination therapy

The efficacy of interferon (IFN) monotherapy for non-responders to pegylated interferon (PEG-IFN) plus ribavirin (RBV) combination therapy is still unclear. To evaluate the impact of IFN monotherapy on biochemical response, 200 consecutive patients infected with HCV genotype 1b, who received low-dose intermittent IFN-alpha monotherapy, were investigated. A median IFN dose per day of 3 million units was administered during a median period of 74 weeks. As a whole, the ALT normalization rates were 50.5, 65.9, 58.4, and 61.7% at 4, 12, 24, and 48 weeks, respectively. In 40 patients, who had abnormal AFP levels at the start of treatment, 52.5% achieved normalization of AFP within 48 weeks. Multivariate analysis identified indocyanine green retention rate at 15 min as the parameter that influenced significantly and independently ALT normalization. ALT normalization rates of patients who were predicted to be poor responders to PEG-IFN plus RBV combination therapy (but not substitutions of amino acid 70 and/or 91 in the HCV core region, female sex, and lower levels of low-density lipoprotein cholesterol) were similar to others. Furthermore, the ALT normalization rates in non-responders to combination therapy were 29.2, 60.9, 60.0, and 40.0% at 4, 12, 24, and 48 weeks, respectively. The results suggest that low-dose intermittent IFN monotherapy is an efficacious therapeutic regimen for patients unsuitable for PEG-IFN plus RBV, including non-responders, because it can lead to ALT normalization and thus a reduced risk of hepatocarcinogenesis.

HCV replication and statin pleotropism: an adjuvant treatment panacea?

With optimal treatment regimens for hepatitis C still under investigation, novel agents that may improve sustained virologic response (SVR) are needed. The targeting of host lipid metabolism, particularly via the cholesterol-lowering 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors or statins, represents a novel approach to hepatitis C therapy and has been proven beneficial in vitro. The study in this issue of the Journal is the first prospective trial that shows benefit, albeit modest, of statin therapy in vivo. While limited by heterogeneous patient population and overall small numbers, this study provides hope that use of statins in combination with standard therapy pegylated interferon and ribavirin may improve SVR.

Dysmetabolic changes associated with HCV: a distinct syndrome?

Although not associated with the metabolic syndrome, HCV is linked with impaired insulin signalling, insulin resistance, hypocholesterolemia and steatosis which represent a distinct HCV-associated dysmetabolic syndrome. Insulin resistance affects the development of diabetes, fibrosis, impaired response to antivirals and perhaps hepatocellular carcinoma risk. HCV infection is associated with hypocholesterolemia and steatosis reversible after sustained virologic response. A "viral", and a "metabolic" steatosis exist as function of viral genotypes. Little is known about the possible role of HCV in further components of the metabolic syndrome such as atherosclerosis, obesity, arterial hypertension, hyperuricemia and thrombotic risk factors.

Fluvastatin inhibits hepatitis C replication in humans

BACKGROUND Hepatitis C viral (HCV) infection is the leading cause of death due to liver disease in the United States. Currently, pegylated interferon and ribavirin produce sustained viral remission in only 50% of patients. Additional agents are needed to increase the cure rate. In vitro experiments show strong antiviral effects of fluvastatin against HCV.

OBJECTIVES

To assess the safety and antiviral effects of fluvastatin in chronic HCV carriers.

METHODS

31 veterans with chronic HCV were prospectively given oral doses of fluvastatin, 20 to 320 mg/day, for 2-12 weeks with weekly monitoring of HCV RNA and liver tests. Reductions of viral load (P < 0.01) versus a control group were considered suppressive.

RESULTS

With 80 mg a day or less, 11/22 (50%) patients responded by lowering HCV RNA. The first lowering occurred within 4 weeks (9/11, 82%). The greatest weekly change in HCV RNA level was a 1.75 log(10) reduction. When lowered in responders, the viral load remained relatively constant for 2-5 weeks (7/9, 78%), or on the next test rebounded immediately to a non-significant change from, baseline (n = 2). Continued lowering of virus was seen in 2/19 (22 %) patients when the study ended. We found no evidence of liver tests worsening.

CONCLUSIONS

FLV used as monotherapy in vivo showed suppressive effects of HCV clinically that are modest, variable, and often short-lived. These findings support "proof-of-concept" for pilot trials combining fluvastatin with standard therapy. Statins and fluvastatin, in particular, appear to be safe for use in hepatitis C.

Baseline serum low-density lipoprotein cholesterol levels predict response to hepatitis C virus therapy in HIV/hepatitis C virus coinfected patients

BACKGROUND

High levels of serum low-density lipoprotein cholesterol are associated with better response to pegylated interferon and ribavirin in hepatitis C virus monoinfected patients. There are no data concerning this topic in HIV/hepatitis C virus coinfected patients in whom lipid disorders are particularly common.

OBJECTIVE

To assess the association between baseline lipid levels and sustained virologic response to pegylated interferon and ribavirin in coinfected patients.

METHODS

A total of 260 HIV/hepatitis C virus coinfected patients under treatment with pegylated interferon and ribavirin and who had a baseline serum lipid profile were included in this retrospective study.

RESULTS

Thirty-eight (24%) patients with genotypes 1-4 and 64 (63%) with genotypes 2-3 achieved sustained virologic response. Forty-nine (44%) patients with serum low-density lipoprotein cholesterol levels 100 mg/dl or more showed sustained virologic response compared with 53 (36%) with lower values [adjusted odds ratio: 2.51; 95% confidence interval: 1.40-4.87; P = 0.003]. This association was independent of the remaining predictors of sustained virologic response which were genotypes 2-3, plasma hepatitis C virus RNA 600,000 IU/ml or less, exposure to at least 80% of the planned therapy and lack of concomitant antiretroviral therapy. The rate of sustained virologic response in patients with genotype 1 and low-density lipoprotein cholesterol at least 100 mg/ml was 31% compared with 17% in those with lower values (adjusted odds ratio: 2.19; 95% confidence interval: 1.04-4.66; P = 0.040). The corresponding figures in subjects with genotypes 2-3 were 73 and 58% [2.71 (0.99-7.46); P = 0.054]. No other lipid was associated with response.

CONCLUSION

Higher low-density lipoprotein cholesterol levels predict sustained virologic response to pegylated interferon and ribavirin in HIV/hepatitis C virus coinfected patients. This might be used to improve the rate of sustained virologic response in this setting.

Efficacy in patients with dose reduction in combination therapy of peginterferon and ribavirin for chronic hepatitis C

OBJECTIVE

The aim of this study was to elucidate efficacy after dose reduction in combination therapy of peginterferon and ribavirin for chronic hepatitis C.

METHODS

Inclusion criteria were hepatitis C virus (HCV) genotype 1b, serum HCV RNA level of >/=100 KIU/ml, dose reduction of peginterferon and/or ribavirin between the first 4 weeks and 20 weeks after the initiation of treatment. 164 patients were enrolled in this retrospective cohort study. Predictive factors for sustained viral response (SVR) after dose reduction were examined.

RESULTS

Out of the 146 patients treated with dose reduction, 57 had SVR. Multivariate analysis showed that SVR occurred when serum HCV RNA at the time of dose reduction was negative (p < 0.001) and total ribavirin dose was >/=100% of the anticipated total dose (p < 0.001). 57% (55/97) of patients with undetectable serum HCV RNA at the time of dose reduction had SVR. In contrast, only 4% (2/49) of patients with detectable serum HCV RNA at the time of dose reduction had SVR.

CONCLUSIONS

On dose reduction of combination therapy for chronic hepatitis C, undetectable serum HCV RNA at the time of dose reduction and attainment of the total ribavirin dose of >/=100% enhance SVR.

Amino acid substitutions in the hepatitis C virus core region are the important predictor of hepatocarcinogenesis

We showed previously that amino acid (aa) substitutions in hepatitis C virus core region (HCV-CR) are negative predictors of virologic response to pegylated interferon (IFN) plus ribavirin therapy. HCV-CR induces hepatocellular carcinoma in transgenic mice, but the clinical impact is still unclear. To evaluate the impact of aa substitutions in HCV-CR on hepatocarcinogenesis, we performed a follow-up study on 313 noncirrhotic consecutive naïve patients infected with HCV genotype 1b who received IFN monotherapy. The median follow-up was 14.7 years. A sustained virologic response (SVR) after the first IFN was achieved by 65 patients (20.8%) (group A). Of 248 patients (79.2%) of non-SVR after first IFN, 112 (35.8%) did not receive additional IFN (group B), and the remaining 136 (43.5%) received multicourse IFN monotherapy (group C). As a whole, cumulative hepatocarcinogenesis rates in double wild-type (arginine at aa 70/leucine at aa 91) of HCV-CR were significantly lower than those in nondouble wild-type. Multivariate analyses identified 3 parameters (fibrosis stage 3, nondouble wild-type of HCV-CR, and group B) that tended to or significantly influenced hepatocarcinogenesis independently. With regard to hepatocarcinogenesis rates in group C according to HCV-CR and the mean alanine aminotransferase (ALT) during IFN-free period, significantly higher rates were noted in patients of nondouble wild-type with ALT levels of more than 1.5 times the upper limit of normal (25.7%) compared with the others (2.4%).

CONCLUSION

Amino acid substitutions in the HCV-CR are the important predictor of hepatocarcinogenesis. In multicourse IFN therapy to nondouble wild-type, we emphasize the importance of reducing the risk of hepatocarcinogenesis by mean ALT during an IFN-free period below 1.5 times the upper limit of normal.

Predictors of viral kinetics to peginterferon plus ribavirin combination therapy in Japanese patients infected with hepatitis C virus genotype 1b

For chronic hepatitis C virus (HCV) infection, evaluation of response to peginterferon (PEG-IFN) plus ribavirin (RBV) therapy based on viral kinetics is useful as an early predictor of treatment efficacy, but the underlying mechanisms of the different viral kinetics to treatment are still unclear. The response to 48-week PEG-IFN-RBV combination therapy was evaluated in 160 Japanese adult patients infected with HCV genotype 1b and determined the rapid virological response (at 4 weeks), early virological response (at 12 weeks), end-of treatment response, and sustained virological response (6 months after end of treatment). The proportion of patients who showed rapid, early and sustained virological, and end-of treatment responses were 50%, 73%, 47%, and 71%, respectively. Furthermore, 66% of patients who achieved early virological response also showed sustained virological response. Multivariate analysis identified substitutions of amino acid (aa) 70 and 91 in the HCV core region (double-wild-type) as a predictor of early HCV-RNA negativity, rapid, early, and sustained virological responses and end-of treatment response, and lipid metabolic factors (high levels of LDL cholesterol and total cholesterol) as predictors of early and rapid virological responses and end-of treatment response. Male sex and low levels of alpha-fetoprotein were other predictors of sustained virological response. Furthermore, female sex and severity of liver fibrosis were determinants of lack of sustained virological response in spite of early virological response. This study identified predictors of efficacy of PEG-IFN-RBV therapy based on viral kinetics in Japanese patients infected with HCV genotype 1b.

Prediction of response to pegylated interferon and ribavirin in hepatitis C by polymorphisms in the viral core protein and very early dynamics of viremia

OBJECTIVE

To evaluate power of amino acid polymorphisms in core protein of hepatitis C virus (HCV) for predicting sustained virological response (SVR) to pegylated interferon (Peg-IFN)/ribavirin, when they were combined with virological response.

METHODS

Peg-IFN/ribavirin was given to 118 patients infected with HCV genotype 1b in high viral loads. Amino acid polymorphisms (Arg70 vs. Gln70 and Leu91 vs. Met91) in combination with on-treatment virological responses were correlated with SVR.

RESULTS

End-of-treatment response (ETR) was achieved in 71% and SVR in 47% of the 118 patients. In multivariate analysis, Arg70 and Leu91, and higher ribavirin dose were independently associated with ETR. In patients with Gln70 and/or Met91, SVR was more frequent in those with than without prompt virological response (PVR) for a decrease in viral load >or=1.0 log by 48 h. Specificity in predicting patients without ETR and SVR, in combination with core polymorphisms, was not different between PVR and early virological response at 12 weeks.

CONCLUSION

Core polymorphisms combined with PVR would be useful in promptly identifying the patients who will not respond to Peg-IFN/ribavirin, thereby avoiding unrewarding side effects and high costs.

Contribution of insertions and deletions to the variability of hepatitis C virus populations

Little is known about the potential effects of insertions and deletions (indels) on the evolutionary dynamics of hepatitis C virus (HCV). In fact, the consequences of indels on antiviral treatment response are a field of investigation completely unexplored. Here, an extensive sequencing project was undertaken by cloning and sequencing serum samples from 25 patients infected with HCV subtype 1a and 48 patients with subtype 1b. For 23 patients, samples obtained after treatment with alpha interferon plus ribavirin were also available. Two genome fragments containing the hypervariable regions in the envelope 2 glycoprotein and the PKR-BD domain in NS5A were sequenced, yielding almost 16 000 sequences. Our results show that insertions are quite rare, but they are often present in biologically relevant domains of the HCV genome. Moreover, their frequency distributions between different time samples reflect the quasispecies dynamics of HCV populations. Deletions seem to be subject to negative selection.