Prediction of the response of chronic hepatitis C to interferon alfa: a statistical analysis of pretreatment variables

Association between human leucocyte antigen-DO polymorphisms and interferon/ribavirin treatment response in hepatitis C virus type 1 infection in Chinese population: a prospective study

OBJECTIVE

The human leucocyte antigen-DO (HLA-DO) gene located in the HLA non-classical class-II region may play a role in treatment response to hepatitis C virus (HCV). This study was conducted to explore the role of single nucleotide polymorphisms (SNPs) in HLA-DO in responding to HCV therapy.

SETTING

All patients were recruited between January 2011 and September 2016 from the Jurong People's Hospital, Jiangsu Province, China.

PARTICIPANTS

A total of 346 chronic hepatitis C (CHC) patients who finished the 48-week pegylated interferon-alpha and ribavirin (PEG IFN-α/RBV) treatment were enrolled in this study. All patients were former remunerated blood donors. The inclusion criteria for patients were as follows: (1) treatment-naive and treated with PEG IFN-α/RBV, (2) HCV RNA was present in serum for over 6 months before treatment, (3) negative for hepatitis B (HBV) or HIV infection and (4) lacked any other hepatic diseases.All participants in this study were Chinese Han population and infected with HCV genotype 1b and treated with subcutaneous PEG IFN-α at a dose of 180 µg once a week with the addition of 800-1000 mg/d RBV according to weight orally for 48 weeks.

RESULTS

The SNPs HLA-DOA rs1044429 and HLA-DOB rs2284191 and rs2856997 of 18 SNPs were correlated with HCV treatment response in the Chinese Han population. The dominant model indicated that patients carrying favourable genotypes at rs1044429 AA and rs2284191 AA were more likely to achieve sustained virological response (SVR) (OR 1.99, 95% CI 1.25 to 3.19; OR 2.71, 95% CI 1.58 to 4.63, respectively), while patients carrying unfavourable genotypes at rs2856997 GG were less likely to achieve SVR (OR 0.48, 95% CI 0.29 to 0.78).

CONCLUSION

Genetic variations at rs1044429, rs2284191 and rs2856997 were independent predictors of HCV treatment response in the Chinese Han population.

Pretreatment prediction of response to peginterferon plus ribavirin therapy in genotype 1 chronic hepatitis C using data mining analysis

BACKGROUND

This study aimed to develop a model for the pre-treatment prediction of sustained virological response (SVR) to peg-interferon plus ribavirin therapy in chronic hepatitis C.

METHODS

Data from 800 genotype 1b chronic hepatitis C patients with high viral load (>100,000 IU/ml) treated by peg-interferon plus ribavirin at 6 hospitals in Japan were randomly assigned to a model building (n = 506) or an internal validation (n = 294). Data from 524 patients treated at 29 hospitals in Japan were used for an external validation. Factors predictive of SVR were explored using data mining analysis.

RESULTS

Age (<50 years), alpha-fetoprotein (AFP) (<8 ng/mL), platelet count (≥ 120 × 10(9)/l), gamma-glutamyltransferase (GGT) (<40 IU/l), and male gender were used to build the decision tree model, which divided patients into 7 subgroups with variable rates of SVR ranging from 22 to 77%. The reproducibility of the model was confirmed by the internal and external validation (r (2) = 0.92 and 0.93, respectively). When reconstructed into 3 groups, the rate of SVR was 75% for the high probability group, 44% for the intermediate probability group and 23% for the low probability group. Poor adherence to drugs lowered the rate of SVR in the low probability group, but not in the high probability group.

CONCLUSIONS

A decision tree model that includes age, gender, AFP, platelet counts, and GGT is useful for predicting the probability of response to therapy with peg-interferon plus ribavirin and has the potential to support clinical decisions regarding the selection of patients for therapy.

A study of best positive predictors for sustained virologic response to interferon alpha plus ribavirin therapy in naive chronic hepatitis C patients

BACKGROUND

The aim of this study was to determine the rate of sustained virological response (SVR) and various factors associated with response rates in chronic hepatitis C infected patients treated with interferon alpha and ribavirin combination therapy.

METHODS

A retrospective review of patients data collected at this Centre from 2001 to 2007 was performed. Out of 731 consecutive patients 400 patients that fulfilled the study criteria were evaluated and subsequently treated with a combination of interferon alpha 2b (3 MU subcutaneously three injections weekly) and ribavirin (800-1200 mg orally daily). Treatment were administered for either 24 weeks or 48 weeks and patients were followed for an additional 6 months thereafter. End of the treatment response (ETR), SVR and side effects were recorded.

RESULTS

Out of 400 patients, 394 completed the entire treatment course and six patients discontinued treatment at month 2. Over 67% responded at the end of treatment and 16% suffered relapse. Among all treated patients, 47.6% males and 56.7% females had sustained viral response with a total combined sustained viral response rate of 50.5%. Rapid response was seen in 46.5% patients. In a multivariate logistic regression analysis, slow virological responders (adjusted OR 2.6 [95% CI 1.9-3.7]), HCV genotype 1&4 (adjusted OR 2.4 [95% CI 1.7-3.5]), pre-treatment viral load > 0.2 MIU/mL (adjusted OR 2.2 [95% CI 1.8-4.2]), Panjabi ethnic group (adjusted OR 1.6 [95% CI 1.0-3.2]) and Age > 40 years (adjusted OR 1.5 [95% CI 0.9-2.4]) were independent risk factors for non response. Side effects were usual and tolerable and only 1.5% discontinued the treatment.

CONCLUSION

The best positive predictor for SVR in this country are: rapid virologic response, HCV genotype 2 & 3, age < 40 years, ethnic race Pashtoons and pre-treatment viral load < 0.2 million IU/mL.

Glucose abnormalities are an independent risk factor for nonresponse to antiviral treatment in chronic hepatitis C

OBJECTIVES

The influence of glucose abnormalities on the efficacy of antiviral treatment is unknown. This study investigated whether glucose abnormalities (impaired fasting glucose and type 2 diabetes) influence the response to antiviral therapy with interferon plus ribavirin in patients with chronic hepatitis C.

METHODS

A total of 178 treatment-naïve patients with chronic hepatitis C treated with combination therapy were retrospectively studied. SVR was assessed after completing treatment. Fasting plasmatic glucose was measured prior to therapy.

RESULTS

Compared with nonresponders (N = 111), patients with SVR (N = 67) had lower plasma glucose (94.1 +/- 12.7 vs 104.4 +/- 25.8 mg/dL, P= 0.001) and a lower prevalence of glucose abnormalities (24.24%vs 44.14%, P= 0.012). The SVR rate was 45.13% in patients with normoglycemia (N = 113), 28.26% in patients with impaired fasting glucose (N = 46), and 15.78% in type 2 diabetic patients (N = 19) (P < 0.001). Multivariate logistic regression identified genotype 1 (OR 1.55, 95% CI 1.01-2.41, P= 0.05), gamma-glutamyltranspeptidase level (OR 6.41, 95% CI 1.86-22.07, P= 0.003), and presence of glucose abnormalities (OR 2.33, 95% CI 1.04-5.20, P= 0.039) as being independently associated with the absence of an SVR. In addition, patients with glucose abnormalities (N = 65) showed a lower virological response rate when compared with a subgroup of normoglycemic patients (N = 65) matched for sex, age, and liver fibrosis (24.6%vs 44.6%, P= 0.001).

CONCLUSIONS

Glucose abnormalities are an independent predictor of poor virological response to combined therapy in hepatitis C virus infected patients.

Hepatitis C and steatosis

Hepatitis C infection and non-alcohol-related hepatic steatosis are the most common liver diseases worldwide, and both conditions often co-exist in the same patient. Hepatitis C virus (HCV) genotype 3 directly induces development of steatosis, whereas in patients with non-genotype 3 chronic hepatitis C infection, insulin resistance plays a key role in the pathophysiology of steatosis. Insulin resistance and its clinical components including obesity, hyperglycemia, hypertriglyceridemia, increased blood pressure, and low HDL-cholesterol levels are often seen in patients with chronic hepatitis C infection. Both increased adipocity and presence of steatosis may increase the risk of fibrosis progression, and both have been associated with a decreased rate of response to antiviral treatment. Hence, liver steatosis in the setting of HCV infection is a distinct condition with specific clinical and prognostic implications. Accumulating evidence suggests that weight management may lead not only to a decrease in steatosis but also improvement in fibrosis severity. However, further studies are necessary to determine whether weight reduction improves response to antiviral therapy.

Ribavirin with either standard or pegylated interferon to treat recurrent hepatitis C after liver transplantation

AIM

To investigate the efficacy of two anti-viral protocols in hepatitis C virus-reinfected liver transplant recipients.

METHODS

In this prospective study, 26 liver transplant patients were treated with standard interferon-alpha2b for 12 months or standard interferon-alpha2b for 3 months followed by pegylated interferon-alpha2b for 9 months. Interferon was combined with ribavirin in all patients. The histological course of the study population was compared with an untreated historic control group (n = 38) with similar baseline characteristics.

RESULTS

The sustained virological response rates in the standard interferon group and in the pegylated interferon group were 27.3% and 26.7%, respectively. Only 29% of patients with sustained virological response had end of treatment histological response, whereas 47% of viral non-responders showed end of treatment histological response. The percentage of patients with histological improvement was significantly higher in the study population when compared to the controls. Univariate analysis indicated that hepatitis C virus genotype non-1, high baseline alanine aminotransferase, the time interval between liver transplant and interferon therapy and the body mass index predicted sustained virological response. In the multivariate model, baseline alanine aminotransferase and the body mass index remained a significant predictor of sustained virological response.

CONCLUSIONS

Both treatment regimens offer similar efficacy profiles. Failure to eradicate hepatitis C virus should not lead to treatment discontinuation if serial liver biopsies demonstrate histological response.

Leptin restores plasma cholesterol, glucose and weight loss induced by IFNalpha treatment

Leptin, an adipokine, a major regulator of food intake, was recently suggested to play a role in immune response. We previously showed that weight reduction following IFNalpha therapy is due, at least in part, to direct induction of adipose tissue apoptosis. We now studied the effect of leptin on IFNalpha treated adipocytes in vitro and in vivo. Diet induced obese C57/B6 mice were treated continually with recombinant (r) IFNalphaA/D + leptin (100 U/g body weight + 10 microg/day, respectably) or leptin (10 microg/day) alone for 8 days. Co-administration of IFNalphaA/D + leptin significantly reduced plasma cholesterol (P<0.001), glucose (P<0.007) and pro-apoptotic protein levels (P<0.05). Additionally, co-administration prevented loss of body weight due to adipocyte apoptosis. Thus, leptin co-administration with IFNalphaA/D decreases some of the side effects of IFNalpha administration such as weight loss, cholesterol and glucose levels.

Non-response to antiviral therapy is associated with obesity and increased hepatic expression of suppressor of cytokine signalling 3 (SOCS-3) in patients with chronic hepatitis C, viral genotype 1

BACKGROUND

Interferon alpha (IFN-alpha) activated cellular signalling is negatively regulated by inhibitory factors, including the suppressor of cytokine signalling (SOCS) family. The effects of host factors such as obesity on hepatic expression of these inhibitory factors in subjects with chronic hepatitis C virus (HCV) are unknown.

OBJECTIVES

To assess the independent effects of obesity, insulin resistance, and steatosis on response to IFN-alpha therapy and to determine hepatic expression of factors inhibiting IFN-alpha signalling in obese and non-obese subjects with chronic HCV.

METHODS

A total of 145 subjects were analysed to determine host factors associated with non-response to antiviral therapy. Treatment comprised IFN-alpha or peginterferon alpha, either alone or in combination with ribavirin. In a separate cohort of 73 patients, real time-polymerase chain reaction was performed to analyse hepatic mRNA expression. Immunohistochemistry for SOCS-3 was performed on liver biopsy samples from 38 patients with viral genotype 1 who had received antiviral treatment.

RESULTS

Non-response (NR) to treatment occurred in 55% of patients with HCV genotypes 1 or 4 and 22% with genotypes 2 or 3. Factors independently associated with NR were viral genotype 1/4 (p < 0.001), cirrhosis on pretreatment biopsy (p = 0.025), and body mass index > or = 30 kg/m2 (p = 0.010). Obese subjects with viral genotype 1 had increased hepatic mRNA expression of phosphoenolpyruvate carboxy kinase (p = 0.01) and SOCS-3 (p = 0.047), in comparison with lean subjects. Following multivariate analysis, SOCS-3 mRNA expression remained independently associated with obesity (p = 0.023). SOCS-3 immunoreactivity was significantly increased in obesity (p = 0.013) and in non-responders compared with responders (p = 0.014).

CONCLUSIONS

In patients with chronic HCV viral genotype 1, increased expression of factors that inhibit interferon signalling may be one mechanism by which obesity reduces the biological response to IFN-alpha.

Steatosis: co-factor in other liver diseases

The prevalence of fatty liver is rising in association with the global increase in obesity and type 2 diabetes. In the past, simple steatosis was regarded as benign, but the presence of another liver disease may provide a synergistic combination of steatosis, cellular adaptation, and oxidative damage that aggravates liver injury. In this review, a major focus is on the role of steatosis as a co-factor in chronic hepatitis C (HCV), where the mechanisms promoting fibrosis and the effect of weight reduction in minimizing liver injury have been most widely studied. Steatosis, obesity, and associated metabolic factors may also modulate the response to alcohol- and drug-induced liver disease and may be risk factors for the development of hepatocellular cancer. The pathogenesis of injury in obesity-related fatty liver disease involves a number of pathways, which are currently under investigation. Enhanced oxidative stress, increased susceptibility to apoptosis, and a dysregulated response to cellular injury have been implicated, and other components of the metabolic syndrome such as hyperinsulinemia and hyperglycemia are likely to have a role. Fibrosis also may be increased as a by-product of altered hepatocyte regeneration and activation of bipotential hepatic progenitor cells. In conclusion, active management of obesity and a reduction in steatosis may improve liver injury and decrease the progression of fibrosis.

Amantadine therapy for chronic hepatitis C

OBJECTIVE

Although treatment of hepatitis C has improved, up to 50% do not respond to standard therapy with interferon regimes or cannot tolerate the treatment due to side effects. The purpose of the present investigation was to evaluate the safety and effectiveness of the antiviral drug amantadine for the treatment of hepatitis C in those who had either previously failed interferon therapy or were not candidates for interferon.

DESIGN

A prospective double-blind randomized placebo-controlled trial.

SETTING

Outpatient research clinic of a teaching hospital.

PATIENTS/PARTICIPANTS

One hundred fifty-two patients with confirmed hepatitis C with abnormal liver enzymes, detectable hepatitis C RNA in the blood, and abnormal liver histology by biopsy were randomized to receive treatment or placebo.

MEASUREMENTS AND MAIN RESULTS

Patients received either amantadine 100 mg twice daily by mouth or placebo for 6 months. After 6 months, placebo-treated patients were crossed over and treated with amantadine for 6 months and amantadine-treated subjects received 6 additional months of therapy. Amantadine therapy resulted in a significant decline in serum alanine aminotransferase compared to placebo (P =.03). Nine percent cleared the virus at the end of therapy and 6.8% had a sustained virologic response 6 months after discontinuation of amantadine, but this was not statistically significant. Side effects were minimal, and the social quality of life survey improved with 12 months of amantadine (P =.02).

CONCLUSIONS

Oral amantadine may provide a safe alternative treatment for those patients who are intolerant or unresponsive to interferon.

High body mass index is an independent risk factor for nonresponse to antiviral treatment in chronic hepatitis C

The aim of this study was to determine if body mass index (BMI) was an independent predictor of response to antiviral treatment in patients with chronic hepatitis C. A retrospective review was performed of all patients at a single center with chronic hepatitis C treated with antiviral medication from 1989 to 2000. A sustained response was defined as either negative hepatitis C virus (HCV) RNA by polymerase chain reaction and/or normal alanine aminotransferase (ALT) level (only in those treated before availability of HCV RNA testing) 6 months following completion of therapy. All patients were classified into one of 3 groups according to BMI (normal, <25 kg/m(2); overweight, 25-30 kg/m(2); obese, >30 kg/m(2)). A total of 253 patients were treated with either interferon (IFN) monotherapy or IFN in combination with ribavirin. Patients were excluded if predetermined clinical characteristics were unavailable. Using logistic regression, and after adjusting for the examined variables (age, sex, history of alcohol consumption >50 g/d, cirrhosis on pretreatment biopsy, and BMI), likelihood ratio tests showed significant differences in response to treatment according to BMI group (P =.01), genotype (P <.01), and cirrhosis (P <.01). Those with genotypes 2 or 3 had an odds ratio (OR) for success of 11.7 compared with those with genotype 1, cirrhotic patients had an OR of 0.15 compared with noncirrhotic patients, and obese patients had an OR of 0.23 compared with normal and overweight patients. Hepatic steatosis was not an independent risk factor for response to antiviral treatment. In conclusion, obesity, only when defined as a BMI greater than 30 kg/m(2), is an independent (of genotype and cirrhosis) negative predictor of response to hepatitis C treatment.

Predictive role of serum procollagen III peptide and Knodell's index in survival prognosis of patients with hepatitis B virus liver cirrhosis

OBJECTIVE

The objective of the study was to improve the accuracy of survival prognosis in patients with liver cirrhosis using procollagen III peptide (PIIIP), as a marker of inflammation and fibrogenesis, and Knodell's histologic activity index (KI) in addition to previously used prognostic factors.

PATIENTS AND METHODS

Five-year survival was followed in a group of 75 patients with hepatitis B virus (HBV) liver cirrhosis (patients testing anti-HBe positive and HBV-DNA negative). There were 31 patients with compensated cirrhosis and 44 with decompensated cirrhosis. The diagnostic procedure included clinical, laboratory, ultrasound and pathohistologic examination. We combined PIIIP and KI with other significant variables to achieve the highest possible sensitivity, specificity and accuracy for survival prognosis in HBV liver cirrhosis. The models were compared using ROC analysis.

RESULTS

At the end of the five-year period of survival follow-up, there were 39 survivors and 36 patients had died (only three died from an extrahepatic cause). In the quantitative model, the discriminant canonical function (DCF) identified PIIIP, bilirubin, prothrombin time, ascites and KI as statistically significant parameters in the prognosis of five-year survival. Calculation of the score based on DCF yielded an accuracy of 89.3%. In the semiquantitative model, the analysis of variance identified PIIIP, bilirubin, albumin, pro-thrombin time, alkaline phosphatase, ascites and KI as significant variables. When PIIIP was added to the clinicohistologic diagnosis, Child-Pugh score and KI, the level of accuracy improved by 12% (from 78% to 90%), 11% (from 79% to 90%) and 10.6% (from 80% to 90.6%), respectively. When calculated with the three biochemical parameters (alkaline phosphatase, PIIIP and bilirubin) and KI identified by DCF, the accuracy was 90.6%.

CONCLUSION

Combining PIIIP and KI with other prognostic parameters is useful in achieving a better precision of survival prognosis in patients with HBV liver cirrhosis.

Review article: indicators and predictors of response to anti-viral therapy in chronic hepatitis C

The complications of chronic hepatitis C, including cirrhosis and hepatocellular carcinoma, are expected to increase dramatically world-wide over the next 10-20 years. Immunomodulatory/anti-viral therapy, employing interferon alfa both alone and in combination with ribavirin, affords the only effective treatment for hepatitis C. Accurate early prediction of response to interferon therapy may decrease or eliminate unnecessary or ineffective treatment, permit greater flexibility in tailoring therapy on an individual basis, and enhance the cost-effectiveness of treatment. Liver biopsy provides valuable information about the baseline severity and subsequent progression of hepatitis C. Severe fibrosis or cirrhosis on the pre-treatment liver biopsy is associated with decreased response rates. The measurement of viral RNA levels and genotyping may be used to optimize individual patient treatment. Genotype non-1 and a low viral load are the most significant pre-treatment indicators of sustained virological response. The most reliable predictor of a poor virological response is continued seropositivity for viral RNA during therapy. Therefore, a decision to stop or continue treatment can be based on a positive viral RNA test at 12 weeks for interferon-naive patients receiving interferon or pegylated interferon therapy.

Hepatitis C viral genotype influences the clinical outcome of patients with acute posttransfusion hepatitis C

Most patients with an acute infection of hepatitis C virus (HCV) will develop chronic hepatitis, and only about 15-20% of the cases will resolve spontaneously. The mechanism for the different outcomes in patients with acute HCV infection remains unclear. HCV genotype has been recognized as an important factor affecting the clinical course and outcome of chronic hepatitis C patients. In order to evaluate the role of HCV genotype in the clinical course and outcome of acute posttransfusion hepatitis C, 67 patients with acute posttransfusion hepatitis C from a prospective study of posttransfusion non-A, non-B hepatitis were enrolled. Thirty-nine patients (58.2%) were HCV genotype 1b. Among the 67 patients with acute posttransfusion hepatitis C, 53 (79.1%) progressed to chronic hepatitis. Significantly more patients with genotype 1b than non-1b genotypes developed chronic hepatitis (89.7% vs. 64.3%; P = 0.019). There was no significant difference in gender, mean age, amount of transfused blood, hepatitis symptoms, jaundice, incubation period, peak serum alanine transaminase, or serum HCV RNA titer between patients with HCV genotype 1b and non-1b infections. Patients who developed chronic hepatitis had a significantly greater incidence of genotype 1b infection (66.0% vs. 28.6%; P = 0.013) and a longer incubation period (7.3 weeks vs. 5.4 weeks; P = 0.052) than patients whose infection was resolved. Patients with a genotype 1b infection that resolved itself spontaneously all had an incubation period of less than 6 weeks. Multivariate logistic regression analysis revealed that genotype 1b and an incubation period > or = 6 weeks were significant predictive factors for the development of chronic hepatitis. Therefore, the HCV genotype can influence the outcome of patients with acute HCV infection.

Gamma glutamyl transferase

Serum gamma-glutamyl transferase (GGT) has been widely used as an index of liver dysfunction and marker of alcohol intake. The last few years have seen improvements in these areas and advances in understanding of its physiological role in counteracting oxidative stress by breaking down extracellular glutathione and making its component amino acids available to the cells. Conditions that increase serum GGT, such as obstructive liver disease, high alcohol consumption, and use of enzyme-inducing drugs, lead to increased free radical production and the threat of glutathione depletion. However, the products of the GGT reaction may themselves lead to increased free radical production, particularly in the presence of iron. There have also been important advances in the definition of the associations between serum GGT and risk of coronary heart disease, Type 2 diabetes, and stroke. People with high serum GGT have higher mortality, partly because of the association between GGT and other risk factors and partly because GGT is an independent predictor of risk. This review aims to summarize the knowledge about GGT's clinical applications, to present information on its physiological roles, consider the results of epidemiological studies, and assess how far these separate areas can be combined into an integrated view.

Variations within hepatitis C virus E2 protein and response to interferon treatment

To determine whether the hepatitis C virus (HCV) E2 PePHD sequence (aa 659-670; PKR-eIF2alpha phosphorylation homology domain) is the determinant for the response of interferon treatment, we have analyzed PePHD sequences in HCV-infected patients who had received interferon-alfa treatment. The PePHD sequence from all (6/6) of the patients, who are non- or partial responders to the interferon treatment, is the wild-type sequence (RSELSPLLL-TT, consensus sequence of HCV-1a and HCV-1b). However, there are sequence variations from more than half (5/9) of the patients, who are complete responders to the treatment. We have also analyzed the NS5A ISDR sequence (aa 2209-2248, interferon sensitivity-determining region) variation in HCV-1b-infected patients. No such correlation has been observed. Thus, our data suggest that HCV E2 should play a more important role than NS5A in determining the interferon responses.

High-dose interferon plus ribavirin in chronic hepatitis C not responding to recombinant alpha-interferon

BACKGROUND

Recently, the combination treatment of recombinant alpha-interferon plus ribavirin has been proposed for chronic hepatitis C patients unresponsive to previous therapy with recombinant alpha-interferon alone.

AIM

To determine the effectiveness of the combination therapy for the re-treatment of chronic hepatitis C patients unresponsive to previous interferon therapy. Immediate and long-term follow-up data are reported.

PATIENTS AND METHODS

A series of 100 patients with chronic hepatitis C not responding to recombinant alpha-interferon 3 MU tiw, were randomly assigned to two groups of 50 patients each: Group A, treated with recombinant alpha-interferon therapy for an additional six months but at a double dosage (6 MU tiw) in association with ribavirin. Group B, same treatment as group A but without ribavirin. All patients responsive to therapy were then followed-up for at least 12 months. At the end of the treatment and at the end of the follow-up period, we distinguished between complete responses (return to normal of alanine aminotransferase with undetectable serum HCV-RNA] and biochemical responses (return to normal of alanine aminotransferase still with detectable viraemia).

RESULTS

Side-effects were observed only in patients treated with recombinant alpha-interferon plus ribavirin: 12% discontinued the therapy due to haemolytic anaemia. In group A, the percentages of end-of-treatment complete response, end-of-treatment biochemical response, sustained complete response, and sustained biochemical response, were 38%, 20%, 8%, and 14%, respectively, whilst in group B, these percentages were 12%, 16%, 6%, and 16%, respectively.

CONCLUSION

The results indicate that in patients with chronic hepatitis C unresponsive to previous recombinant alpha-interferon therapy, re-treatment with higher recombinant alpha-interferon doses, either alone or in combination with ribavirin, lead to mild long-term benefit. However, the satisfactory end of treatment complete response in group A suggests that a significant percentage of patients are sensitive to the combination therapy; and that a more aggressive therapeutic protocol in this selected subset of patients could result in a larger number of long-lasting responses leading, in turn, to a more favourable cost-effect ratio.

Early predictors of response to treatment in patients with chronic hepatitis C

The term sustained response should be applied to patients with negative serum HCV-RNA and normal values of serum transaminases 6 months after interferon withdrawal. To investigate which factors identify sustained responders early during treatment we analysed 18 reports which used the definition sustained response. Eight reports, comprising 988 patients, have studied the value of early clearance of viraemia as a predictor of sustained response using multivariate analysis and all of them found that this was the strongest predictor of a sustained response. Determination of HCV-RNA 4 or 12 weeks after initiation of IFN therapy predicts treatment outcome more accurately than baseline viral load (the best pre-treatment predictor). ALT levels during the first 12 weeks of treatment have lower predictive value than early viral clearance. The sensitivity of a negative HCV-RNA test is similar at week 4 and at week 12 of therapy while the specificity and the accuracy is higher at week 4. The value of persistent viraemia for early prediction of no response is higher than 97%, with similar values at weeks 4 and 12. Persistence of HCV-RNA in serum at week 4 strongly indicates that the patient will not respond to treatment and in these cases interruption of treatment or other therapeutic options could be considered.

Interferon plus ribavirin in chronic hepatitis C non-responders to recombinant alpha-interferon

The aim of this study was to evaluate the most appropriate therapeutic protocol for patients with chronic hepatitis C not responding to a previous course of recombinant interferon alpha-2b (rIFN). Sixty patients were randomly assigned to two groups of 30 subjects each: group A was treated with double dose of the same type of rIFN (6 MU t.i.w.) plus ribavirin for 6 months; group B was treated with the same rIFN dose and duration as group A, but without ribavirin. An end of treatment complete response (ETCR) was defined as alanine transaminase (ALT) normalization with undetectable serum HCV-RNA at the end of the treatment, while an end of treatment biochemical response (ETBR) as ALT normalization with still detectable viraemia. The two groups were homogeneous. The patients with ETCR or ETBR were than followed-up for at least 1 year. A sustained biochemical response (SBR) was defined as the persistence of normal ALT with still detectable viraemia after a 12-month follow-up, and a sustained complete response (SCR) as the persistence of normal ALT with undetectable viraemia. Side-effects were only observed in patients treated with rIFN plus ribavirin: four cases (13%) discontinued the therapy owing to haemolytic anaemia. Combination therapy induced an ETCR in 11 patients (37%) and an ETBR in six (20%), while a SCR was observed in two subjects (7%) and a SBR in four (13%). The use of a double dose of rIFN alone obtained an ETCR in four cases (13%) and an ETBR in five (17%), with a SCR in two (7%) and a SBR in three (10%). Hence, both combination therapy and single treatment with higher rIFN doses were unable to show statistically significant long-term benefits in patients with chronic hepatitis C resistant to a previous course of rIFN treatment.

Prediction of relapse or sustained response in biochemical responders by serum hepatitis C virus RNA monitoring during interferon therapy

Normalization of serum aminotransferase levels is achieved in approximately 50% of chronic hepatitis C patients treated with interferon (IFN); however, in about one-half of these patients the hepatitis relapses after therapy. In this study we investigated the efficacy of serum hepatitis C virus (HCV) RNA monitoring during IFN therapy to predict the outcome of a biochemical end-of-treatment (ETR) response. Eighty patients with chronic hepatitis C received leucocyte (natural) IFN-alpha (13 patients) or recombinant IFN-alpha2a (67 patients). Antiviral therapy was given for 12 months to 43 (53.7%) responders and this group was analysed further. During follow-up, 15 relapsed and 28 showed a sustained response (median follow-up 50 months, range 39-67 months). Viraemia was monitored at baseline, and at months 1, 3, 6, 9 and 12 of treatment, by nested polymerase chain reaction (PCR) (sensitivity 10-100 copies ml-1). A combination of positive nested PCR and HCV RNA values at the 3rd and 6th months of treatment was 100% predictive of relapse (sensitivity, 66.6%; specificity, 100%). A combination of negative nested PCR and HCV RNA values at the 1st and 3rd months of treatment was 100% predictive of sustained response (sensitivity, 39.3%; specificity, 100%). In conclusion, serum HCV RNA monitoring is an appropriate and reliable tool for predicting early outcome of the biochemical ETR response after IFN discontinuation. This could be useful in the modulation of therapeutic management of chronic hepatitis C.

Bile acids modulate the interferon signalling pathway

We have previously shown that cholestasis and bile acids inhibit 2', 5' oligoadenylate synthetase (OAS) activity in the liver and in primary hepatocyte cultures. Here, we assessed the influence of bile acids on interferon (IFN) pathway activation in three hepatoma cell lines. In HepG2 cells, bile acids (100-200 micromol/L) inhibited IFN-induced 2',5' OAS activity to an extent depending on their surface activity index. In Western blot analysis, IFN-induced expression of two major antiviral proteins, MxA and OAS p100, was reduced by 54% +/- 8% and 44% +/- 12%, respectively, when cells were preincubated for 4 hours with 100 micromol/L chenodeoxycholic acid (CDCA). In the same conditions, CDCA did not modify the IFN-induced signal transducers and activators of transcription (STAT)s tyrosine phosphorylation. In contrast, it reduced IFN-induced MxA promoter activity by 60%. The inhibitory effect of CDCA was not mediated by a 4beta-phorbol 12beta-myristate 13alpha-acetate (PMA)-sensitive protein kinase C (PKC)-dependent pathway. Finally, using CHO cells stably expressing a functional human bile acid carrier (Na+-dependent taurocholate cotransporting polypeptide [NTCP]), we found that bile acid inhibition of the IFN pathway occurred in the range of more physiological concentrations (12-50 micromol/L). In summary, our results provide strong evidence that bile acids inhibit the induction of proteins involved in the antiviral activity of IFN. This might partly explain the lack of responsiveness to IFN therapy in some patients with advanced chronic viral liver diseases.

Prediction of successful outcome in a randomised controlled trial of the long-term efficacy of interferon alpha treatment for chronic hepatitis C

To evaluate the efficacy of a 12-month course of recombinant interferon alpha (IFN-alpha2b), and to assess predictive factors of successful response to IFN therapy in chronic active hepatitis C (HCV CAH), 242 patients with histologically proven HCV CAH were assigned randomly to two groups, one treated with IFN-alpha2b (3 MU three times weekly, intramuscularly), the other untreated. To determine the efficacy of IFN-alpha2b 12 months after therapy, a second liver biopsy was carried out on 100 treated patients and 27 untreated patients. The biochemical, virological, and serological response of patients followed up for at least 50 months after treatment was also evaluated to confirm the efficacy of IFN-alpha2b. The genotypes of infecting HCV, anti-HCV core IgM, and HCV-RNA concentrations were also analysed and the predictors of response determined by univariate and multivariate analyses. Response was defined in terms of the normalisation of aminotransferase activities and the disappearance of HCV-RNA. The overall long-term response was 39.4%. Anti-HCV core IgM levels were significantly lower in long-term responders. Patients with increased levels of IgM anti HCV core (>3.8 sample/cut-off), infected with genotype 1b were nonresponders. Liver histology improved significantly in patients with long-term response. Multivariate analysis identified three independent predictors of the likelihood of long-term response to IFN therapy: age younger than 40 years, basal anti-HCV core IgM levels < or = 3.8, and genotypes other than 1b. These data indicate that the treatment with IFN-alpha2b used in this randomised controlled trial is effective in HCV CAH. Anti-HCV core IgM was the strongest predictor of long-term response in the present study.

The effects of a high dose, short course of interferon on hepatitis C

To shorten the period of interferon (IFN) treatment for chronic hepatitis C, we investigated the clinical efficacy of a regimen using a higher dose and a shorter treatment period. Fifty chronic hepatitis C patients who were hepatitis C virus (HCV)-RNA positive and who were histologically diagnosed as having chronic hepatitis, took part in the study. Virus levels were measured before and 2 weeks after starting the treatment. We administered natural IFNalpha, 10 MU, i.m. daily for 2 consecutive weeks and then three times per week for the subsequent 14 weeks (total dose 560 MU). Patients who were HCV-RNA negative at the completion of the therapy and 6 months later, were evaluated as sustained responders (SR; 32%). Those who were not HCV-RNA negative at the two time points were evaluated as non-responders. Nucleotide and clone differences in the hypervariable region (HVR) and predictive factors for prognosis were also analysed. Low virus level and HCV-RNA genotype 2a/2b were the predictors for good prognosis, whereas the numbers of nucleotide differences and clone differences in HVR were not. Sustained responder patients became HCV-RNA negative 2 weeks after starting the treatment at a significantly higher rate, whereas no non-responder patients were HCV-RNA negative at that time. The SR rate (32%) was equivalent to those reported in previous 24 week treatment studies. This IFN therapy using a higher dose and a shorter period was useful.

Prediction of cirrhosis in patients with chronic hepatitis C infection by artificial neural network analysis of virus and clinical factors

The diagnosis of cirrhosis in patients with hepatitis C virus (HCV) infection is currently made using a liver biopsy. In this study we have trained and validated artificial neural networks (ANN) with routine clinical host and viral parameters to predict the presence or absence of cirrhosis in patients with chronic HCV infection and assessed and interpreted the role of the different inputs on the ANN classification. Fifteen routine clinical and virological factors were collated from 112 patients who were HCV RNA positive by reverse transcriptase-polymerase chain reaction (RT-PCR). Standard and Ward-type feed-forward fully-connected ANN analyses were carried out both by training the networks with data from 82 patients and subsequently testing with data from 30 patients plus performing leave-one-out tests for the whole patient data set. The ANN results were also compared with those from multiple logistic regression. The performance of both ANN methods was superior compared with the logistic regression. The best performance was obtained with the Ward-type ANNs resulting in a sensitivity of 92% and a specificity of 98.9% together with a predictive value of a positive test of 95% and a predictive value of a negative test of 97% in the leave-one-out test. Hence, further validation of the ANN analysis is likely to provide a non-invasive test for diagnosing cirrhosis in HCV-infected patients.

Review article: interferon and hepatitis C--factors predicting therapeutic outcome

Hepatitis C chronically infects approximately 1.5% of Americans and is the most common clinical problem facing hepatologists. Since the virus was initially described in 1989, development of an effective therapy has been challenging. Although several different therapeutic agents have been used, no therapy has been shown to reliably eradicate the virus. Interferon-alpha, a cytokine with immunostimulatory and anti-viral properties, has become the therapy of choice for patients with chronic hepatitis C infection. Trials assessing the efficacy of interferon-alpha have characterized host and viral factors predictive of responses to treatment. A thorough understanding of these predictive factors is requisite to providing cost-effective therapeutic decisions for the patient with chronic hepatitis C infection.

Determinants of outcome of compensated hepatitis C virus-related cirrhosis

The aim of this study was to assess the incidence of decompensation (ascites, jaundice, variceal bleeding, and encephalopathy), hepatocellular carcinoma (HCC) and death or liver transplantation in patients with compensated hepatitis C virus (HCV)-related cirrhosis, taking into account the viral genotype and interferon (IFN) therapy. Between 1989 and 1994, 668 patients with no clinical evidence of decompensation were referred to our department for liver biopsy because of positivity for anti-HCV antibodies and elevated aminotransferase activity; 103 of these patients had cirrhosis. The median follow-up was 40 months. Fifty-nine patients were treated with IFN for a mean duration of 11+/-6 months; 3 (5%) had a prolonged biochemical and virological response. Baseline characteristics of IFN-treated and untreated patients were not significantly different. HCV genotypes (InnoLiPa) were predominantly 1b (48%) and 3a (20%). During follow-up, complications of cirrhosis occurred in 26 patients, HCC in 11 patients, and decompensation not related to HCC in 19 patients. Sixteen patients died, 94% of liver disease. Three patients were transplanted for liver failure. The 4-year risk of HCC was 11.5% (annual incidence 3.3%) and that of decompensation was 20%. Survival probability was 96% and 84% at 2 and 4 years, respectively. In multivariate analysis, the absence of IFN therapy was the only independent factor predictive both for HCC and decompensation. A low albumin level at entry and the absence of IFN therapy were the two independent factors predictive of death or liver transplantation. Probability of survival at 2 and 4 years was significantly different between IFN-treated and untreated patients (respectively 97% and 92% vs 95% and 63%, P < .0001). In conclusion, in patients with compensated HCV-related cirrhosis: 1) complications of cirrhosis are frequent, whatever the viral genotype; and 2) the severity of cirrhosis and the absence of IFN therapy are independently predictive of bad outcome.

Hepatitis C

Hepatitis C virus (HCV) infection afflicts millions of people in the United States and worldwide. We examine the epidemiology of HCV infection, the molecular biology of the virus, the pathophysiology of infection, the clinical diagnosis and manifestations of infection, and the treatment of HCV infection.

Alpha-glutathione transferases in HCV-related chronic hepatitis: a new predictive index of response to interferon therapy?

BACKGROUND/AIM

The aim of this study was to evaluate if plasma levels of alpha-glutathione-S-transferases (determined in basal conditions and monthly for 1 year during and 1 year after interferon therapy) could characterize patients who show only a primary response.

METHODS

We studied 48 patients with biopsy-proven, hepatitis C virus ribonucleic acid positive chronic hepatitis treated with interferon: 18 were "Sustained Responders", 12 "Relapsers" and 18 "Non-Responders".

RESULTS

Relapsers showed higher basal levels of alpha-glutathione-S-transferases, which remained higher than normal even when alanine aminotransferases normalized. No correlation was documented between alpha-glutathione-S-transferase levels and all other parameters examined (alanine aminotransferases, gamma-glutamyl-transpeptidase, viremia, and histological activity index).

CONCLUSIONS

These findings suggest that alpha-glutathione-S-transferase levels may be considered a predictive index of response to interferon therapy in chronic hepatitis C patients.

A pilot study on the efficacy of escalating dosage of alpha-interferon for chronic hepatitis C in HIV-infected patients. The Hepatitis/HIV Spanish Study Group

Chronic liver disease caused by hepatitis C virus (HCV) seems to present a more accelerated course in HIV-infected patients, leading to cirrhosis and liver failure in a shorter period of time than in HIV-negative individuals. As efforts to increase life expectancy in HIV-infected people progress, substantial morbidity and mortality from HCV infection is likely to arise amongst subjects infected parenterally, such as injecting drug users, haemophiliacs and transfusion recipients. Preliminary results have suggested that alpha-interferon (IFN) treatment allows higher rates of response in HIV-infected patients with higher CD4+ lymphocyte counts, suggesting a primary dependence of IFN on a preserved immune system in order to act appropriately. In an open, multicentre, prospective trial we analysed whether the use of larger doses of IFN, through an escalating schedule, might overcome the limits imposed by immune dysfunction. An interim analysis performed in 29 patients concluded that escalating the dosage did not improve the rate of response to IFN. In fact, only one (8.3%) out of 12 patients without response after 3 months of being on IFN therapy achieved response after the dosage was increased from 5 MU to 8 MU s.c. three times a week. Moreover, he relapsed 3 months after completion of treatment for 1 year.

Treatment of HCV: approach to difficult cases

The treatment of patients with HCV in itself represents a challenge for the treating physicians, but is particularly difficult in special situations where experience is limited. In patients with normal aminotransferases or an incomplete response to IFN, the safety of IFN administration is not the major issue, but one should consider the limited effectiveness of the therapy. In other patients, such as those with concomitant autoimmune hepatitis, an immunosuppressed state or a major psychiatric illness, IFN can be administered but may be associated with serious risks. In these cases, IFN should be used under strictly supervised circumstances and only by physicians with considerable familiarity with the drug. After needle stick exposures, IFN may prevent progression of acute infection to chronic hepatitis. Finally, in patients with well-established cirrhosis, IFN treatment may prevent decomposition or the development of hepatocellular carcinoma. In each of these categories, treatment must be tailored to the individual case based on good clinical judgment. It is hoped that greater experience, newer therapies, and a better understanding of the natural history of HCV infection will simplify the treatment of these cases that currently present difficult management problems.

Interferon therapy for Japanese hemophiliacs with chronic hepatitis C

Eight Japanese hemophiliacs with chronic hepatitis C (CHC) received interferon (IFN) therapy and four of them (50%) responded completely. Non-responders included 3 double-infected patients: 1 with hepatitis B virus (HBV) and 2 with human immunodeficiency virus-1 (HIV-1). In one of the patients with HIV-1 double infection, the absolute number of CD4+ lymphocytes decreased during IFN therapy. These findings suggest that hemophiliac patients with CHC can respond well to IFN therapy, but in patients who are double-infected with HBV and HIV-1, the indication of IFN therapy should be considered seriously.

Mutations in the NS5A gene of hepatitis C virus in North American patients infected with HCV genotype 1a or 1b

Previous studies from Japan have described an association between a conserved sequence within the hepatitis C virus (HCV) genome and resistance to interferon (IFN) therapy for patients infected with HCV genotype 1b [Enomoto et al. (1995): Journal of Clinical Investigation 96: 224-230; Enomoto et al. (1996): New England Journal of Medicine 334:77-81]. The present study examines amino acid sequences surrounding the putative Interferon Sensitivity Determining Region (ISDR) of the NS5A gene of HCV in 21 North American patients with genotype 1a or 1b infection receiving recombinant IFN therapy. The ISDR consensus or intermediate pattern was observed in 13 of 14 NS5A clones from North American patients infected with genotype 1b. However, we found no evidence of the consensus ISDR sequence in any NS5A clones isolated from 15 patients with genotype 1a infection. In select cases, gel shift analysis showed no significant changes in the clonal frequency of the putative ISDR domain of HCV genotype 1a or 1b infected patients who were either nonresponsive to IFN therapy, or relapsed following withdrawal of IFN therapy. These results suggest that a conserved ISDR domain is neither associated with, nor responsible for, IFN resistance in North American patients infected with HCV genotype 1a, and demonstrate a need for further investigation into the reported association between ISDR consensus sequences and IFN resistance in genotype 1b clones.

Influence of viral genotype and level of viremia on the severity of liver injury and the response to interferon therapy in Spanish patients with chronic C infection

BACKGROUND

We wanted to investigate the influence of viral genotype on the severity of liver injury and response to interferon and whether the level of viremia differs in accordance with genotype, severity of liver disease, and response to interferon in patients with hepatitis C virus (HCV) infection.

METHODS

We studied 118 patients with HCV-related liver disease. HCV genotypes were determined with a line probe assay, and serum HCV RNA levels with a competitive reverse transcription polymerase chain reaction assay.

RESULTS

HCV type 1b was the most prevalent genotype (88%). It was present in 100% of cirrhotic patients, with or without hepatocellular carcinoma (HCC), but only in 78% of patients with chronic hepatitis (P < 0.001). The response to interferon was better in patients infected with non-1b HCV genotypes (P = 0.002). In a multivariate analysis non-1b HCV genotypes and a low hepatic fibrosis correlated with a favorable response to interferon. Among patients with chronic hepatitis those infected with HCV type 1b were older (P < 0.001), and age was the only independent factor associated with HCV type 1b. Viremia levels differed neither between genotypes nor in response to interferon and was significantly lower in patients with cirrhosis and HCC.

CONCLUSIONS

HCV 1b was associated with more severe liver disease and a worse response to interferon therapy. Non-1b genotypes and a lower liver fibrosis were the only independent predictors of a favorable response to interferon. Levels of HCV viremia differed neither among different genotypes nor in response to interferon and decreased with advanced liver disease.

Effect of obesity on pharmacokinetics and biologic effect of interferon-alpha in hepatitis C

To examine potential adverse effects of obesity in reducing the response to interferon-alpha (IFN-alpha) in chronic hepatitis C (HCV), IFN-alpha and HCV RNA levels in serum and the 2',5'-oligoadenylate synthetase (2-5 OAS) levels in peripheral blood mononuclear cells (PBMC) were compared between six obese and five nonobese patients before and after a single, 10 mIU dose of IFN-alpha2b. There were no differences in the mean histologic activity index between the two groups. The maximal IFN concentration and the area under the serum IFN concentration-time curve were higher in nonobese patients. These two parameters were inversely correlated with body weight and body surface area. No differences were found in the mean reduction in HCV RNA levels between the two groups following IFN-alpha. The maximal 2-5 OAS level after treatment divided by the pretreatment 2-5 OAS level (2-5 OAS response ratio) was greater in the nonobese patients, suggesting stronger biologic response upon exposure to exogenous IFN-alpha in nonobese patients.

Genotype, viral load and age as independent predictors of treatment outcome of interferon-alpha 2a treatment in patients with chronic hepatitis C. Construct group

Patients with chronic hepatitis C respond differently when treated with interferon. We randomized 116 patients with chronic hepatitis C in order to compare two dosage regimens of recombinant interferon alpha 2a:3 MIU x 3 per week for 6 months (arm A) or 6 MIU x 3 per week for 3 months and then 3 MIU x 3 per week for 3 months (arm B). There were no significant differences concerning outcome between the two dose regimens: sustained clearance of HCV viremia 6 months after the end of treatment was obtained in 12/59 (20%) in group A compared with 18/57 (32%) in group B (p = 0.24). In patients with genotype 1a, 4/31 (13%), in genotype 1b, none of 9 (0%), 9/15 (60%) in genotype 2, and 17/58 (29%) in genotype 3, showed sustained clearance of HCV viremia 6 months after the end of treatment (p = 0.002). In a stepwise logistic regression analysis, only pretreatment viral load (p = 0.0001), genotype (p = 0.001) and age (p = 0.04) were identified as independent predictors of sustained clearance of HCV viremia. Liver histology as assessed by Knodell index was significantly improved in patients with sustained HCV RNA response 6 months after the end of treatment (5.2 +/- 2.2 vs 2.6 +/- 2.2, p < 0.001), but not in responders with relapse or in non-responders. In conclusion, stepwise logistic regression analysis showed that viral load, HCV genotype and age were the only independent predictors for sustained HCV RNA response.

Predictors of response to interferon therapy

An optimal treatment schedule is the first factor that influences sustained responses to interferon (IFN) therapy. There is growing evidence that prolonged IFN therapy (at least 12 months or longer) increases the sustained response rate. A low viremia at baseline favorably affects the long-term response to IFN. High viral replication does not preclude response, but highly viremic patients tend not to sustain their response. Patients with genotypes 2 and 3 (Simmonds classification) have an improved likelihood of responding compared to patients with genotype 1; unfortunately, genotype 1 predominates in Western countries. The "quasispecies" diversity of hepatitis C virus (HCV) may play a role in determining response to IFN, which is more likely in patients with lesser degrees of HCV diversity. However, studying the nucleotide diversity of the hypervariable region 1 of HCV is a very complex and expensive process that cannot be applied to a large number of patients. The sustained response rate is higher in patients with mild disease than in cirrhotic patients. Cirrhotics should be treated with caution, since IFN therapy could induce serious side effects and decompensation. Baseline predictive factors of response are useful to improve the cost-benefit ratio of IFN therapy but cannot be considered inclusion/exclusion criteria. The decision on how to treat should be based upon the individual characteristics of each patient.

Permanent response to alpha-interferon therapy in chronic hepatitis C is preceded by rapid clearance of HCV-RNA from serum

BACKGROUND/AIMS

Prediction of response to interferon therapy is important in the management of chronic hepatitis C. Pre-therapy data are valuable but they may be inaccurate in some cases. Our aim was to investigate whether the biochemical and virological events that occur early during interferon therapy in chronic hepatitis C may predict the final result of the treatment.

METHODS

ALT and serum HCV-RNA were serially measured in 53 HCV-RNA-positive patients who received a standard 6-month course of interferon therapy. Eleven patients with a sustained response, 23 who responded but subsequently relapsed and 19 who did not respond were studied. HCV-RNA was measured with a commercial kit (Amplicor HCV).

RESULTS

After 4 weeks of treatment, HCV-RNA became negative in 73% of sustained responders, in 26% of transient responders (p = 0.02) and in none of the non-responders. Corresponding figures after 8 weeks of therapy were 82% in sustained responders, 61% in transient responders and 9% in non-responders. The difference between sustained and transient responders at this time was not significant. After 4 weeks of therapy, 82% of sustained responders, 52% of transient responders and none of the non-responders presented normalization of alanine transferase. The difference between sustained and transient responders was not significant. Corresponding figures for normalization of alanine transferase at 8 weeks were 82%, 96% and 0% respectively. At the end of treatment, all sustained responders, 70% of transient responders and none of the non-responders had cleared HCV-RNA from serum.

CONCLUSIONS

A rapid normalization of alanine transferase induced by interferon therapy is associated with response, but does not differentiate between transient and permanent response. In contrast, clearance of HCV-RNA after 4 weeks of treatment, but not after 8 weeks, is significatively associated with sustained response. Testing for HCV-RNA early during interferon administration may be valuable for further decisions concerning therapy in patients with chronic hepatitis C.

Duration of HCV infection as a predictor of nonresponse to interferon

Duration of hepatitis C virus (HCV) infection is a key feature in determining responsiveness to interferon (IFN). Studies assessing its value as a predictive factor in chronic HCV infection show that a long duration of infection reduces the likelihood of a sustained response to IFN (defined as ALT normalization and clearance of serum HCV-RNA). The effect of HCV infection duration is independent of the presence of cirrhosis and level of HCV viremia. Meta-analysis of IFN trials in acute HCV infection shows an obvious effect of the drug on long-term ALT normalization and HCV-RNA clearance. Treatment of HCV infection during the acute or early chronic phase could therefore maximize therapeutic effectiveness.

Predictive factors of a response to interferon therapy in chronic hepatitis C

To determine predictive factors of response to interferon (IFN) therapy in chronic hepatitis C patients, we administered IFN-alpha, 1 6 million U1 intramuscularly daily for 2 consecutive weeks, then three times a week, to 136 patients judged to have chronic hepatitis C virus (HCV) infection according to HCV-RNA positivity. We also investigated the most effective length of IFN-alpha treatment according to efficacy factors, i.e., histological activity index. HCV-RNA genotype, and HCV-RNA levels. patients were classified either into a short-term group (entire treatment period 16 weeks), standard-term group (24 weeks), and long-term group (40 weeks). Patients were assessed as complete responders (CR) if their HCV-RNA became negative and their alanine aminotransferase (ALT) decreased to < or = 39 IU/L after 18 months of treatment or nonresponders in other cases. Results showed that HCV-RNA levels and genotype were statistically significant predictive factors. CR rates in the standard- and long-term groups were significantly higher than in the short-term group (p < 0.05). In patients with low HAI scores, the long-term group showed the highest CR rate. In patients with low virus counts, the CR rate increased to 73% in the 24th week and 100% in the 40th week. CR rates in patients with HCV-RNA genotype 1b and 2a or 2b also increased as the treatment period became longer. For efficacy, a 24-week treatment period was necessary. In patients with mild liver tissue damage or low virus counts, 40 weeks of treatment proved highly useful.

Therapy of chronic viral hepatitis

Interferon alpha is effective therapy for patients with chronic hepatitis B and hepatitis C. Only 20% to 40% of patients, however, have a sustained benefit from therapy. For the majority of patients with these diseases, alternative forms of therapy are needed. Nucleoside analogues appear to be extremely promising for the treatment of chronic hepatitis B and will undoubtedly play a major role in the management of this disease. For chronic hepatitis C, prolonged therapy with interferon, improved patient selection, and combined therapy with multiple agents such as ribavirin may lead to an improved therapeutic response.

Low dose alpha interferon therapy can be effective in chronic active hepatitis C. Results of a multicentre, randomised trial

BACKGROUND

There is some controversy concerning the efficacy of low dose alpha interferon therapy in chronic hepatitis C.

AIMS

To evaluate the effectiveness of treatment with low doses of alpha interferon in chronic hepatitis C.

PATIENTS

One hundred and forty one patients with anti-HCV positive chronic active hepatitis C from six hospitals were enrolled in the study.

METHODS

Patients were randomised to treatment with 5 MU (group A) or 1.5 MU (group B) injections. The dose was reduced in responders from group A or increased in non-responders from group B to maintain treatment with the minimal effective dose. Patients were treated for 48 weeks and followed up for 24 additional weeks with no treatment. Normalisation of alanine aminotransferase (ALT) was used to evaluate response.

RESULTS

A sustained response was seen in eight patients from group A (12%) and in 15 (21%) from group B. This difference was not statistically significant. Increasing the dose of interferon led to sustained response in only five of 58 patients (9%) from group B who did not respond to 1.5 MU injections. In contrast, 15 of 21 patients (71%) in whom ALT remained normal with 1.5 MU injections developed a sustained response. By multivariate analysis sustained response seemed associated with young age and was more frequent in patients with genotype 3 HCV infection. Sustained response was preceded by a rapid normalisation of ALT and was inversely related to the amount of alpha interferon necessary to maintain ALT at low values during treatment.

CONCLUSIONS

Some patients with chronic hepatitis C are very sensitive to alpha interferon and can be successfully treated with low doses. Treatment with higher doses may be effective in a minority of patients who do not respond to low doses.

Virus and host factors are both important determinants of response to interferon treatment among patients with chronic hepatitis C

Virus and host factors have both been linked to the response to interferon treatment among patients with chronic hepatitis C but their relative importance and potential interactions are unclear. Hepatitis C virus genotype and level of viraemia were determined in pretreatment sera from 65 Australian patients treated with interferon-alpha 2b (IFN-alpha 2b), 3 MU tiw for 6 months. Hepatitis C viraemia was quantitated by a competitive reverse transcription-polymerase chain reaction (RT-PCR) method and genotype was determined by a line probe assay. By univariate analysis, there were positive associations between initial (short-term) responses to IFN treatment and younger age (P = 0.004), absence of cirrhosis (P = 0.01), and injecting drug use as risk factor for infection (P = 0.05) but not gender, duration of infection, or level of viraemia. Genotype appeared to be important (P = 0.06) but failed to reach statistical significance. By multivariate analysis, absence of cirrhosis was the only significant independent predictor of treatment response (P = 0.01). Among initial responders, the factors associated with long-term response were the pretreatment HCV RNA titre and the duration of infection. There was a close association between viral genotype, but not viral load, and the severity of liver disease. An interplay of factors determines the outcome of a 6-month course of interferon treatment for hepatitis C. Severity of liver disease, but not the viral load, is the most crucial determinant of initial response to interferon, and histological severity appeared to be influenced by the viral genotype. The level of hepatitis C virus (HCV) viraemia and the duration of infection are independent determinants of long-term response by affecting the relapse rate after interferon treatment.

Tumor necrosis factor alpha gene expression and the response to interferon in chronic hepatitis C

Tumor necrosis factor alpha (TNF-alpha) is a cytokine with pleiotropic properties that is induced in a variety of pathological situations including viral infections. In this work, we analyzed the expression of TNF-alpha gene in patients with chronic hepatitis C. Serum TNF-alpha levels were found to be elevated in all chronic hepatitis C patients including those cases presenting sustained biochemical remission of the disease after interferon therapy. Untreated patients with chronic hepatitis C showed increased TNF-alpha messenger RNA (mRNA) levels in the liver and mononuclear cells as compared with healthy controls. After completion of treatment with interferon, patients experiencing sustained complete response showed values of TNF-alpha mRNA, both in the liver and in peripheral mononuclear cells, within the normal range, significantly lower than patients who did not respond to interferon and than those with complete response who relapsed after interferon withdrawal. Pretreatment values of TNF-alpha mRNA were lower in long-term responders to interferon than in cases who failed to respond to the treatment. Values of TNF-alpha mRNA in the liver or in mononuclear cells were higher in specimens with positive hepatitis C virus (HCV) RNA than in those samples where the virus was undetectable. Neither the intensity of the liver damage nor the amount of HCV RNA in serum or in cells showed correlation with the levels of TNF-alpha transcripts in peripheral mononuclear cells but it was found that high TNF-alpha values were associated with genotype 1b. In conclusion, there is an enhanced expression of TNF-alpha in HCV infection. High levels of this cytokine may play a role in the resistance to interferon therapy.

IL-1 beta and TNF-alpha produced by peripheral blood mononuclear cells before and during interferon therapy in patients with chronic hepatitis C

We investigated the spontaneous and phytohemagglutinin-stimulated production of interleukin-1 beta (IL-1 beta) and tumor necrosis factor-alpha (TNF-alpha) by peripheral blood mononuclear cells in patients with chronic hepatitis C during treatment with interferon-alpha (IFN-alpha). Spontaneous productions of these were significantly higher in patients with chronic hepatitis C than in healthy subjects. For patients prescribed interferon, stimulated production of TNF-alpha was significantly higher in complete responders than in partial responders, but the differences were small between the other cytokine levels and outcome of IFN treatment. Spontaneous production of these cytokines was higher in patients with genotype III with complete response than in genotype III patients with a partial response, but this was not the case in patients with genotype II. There was a negative correlation between these cytokines and histological activity index. Spontaneous production of cytokines was decreased only in complete responders after the administration of interferon. These data suggest that the elevated production of cytokines in patients with chronic hepatitis C may be due to host response to the virus, and monitoring cytokines along with alanine aminotransferase and hepatitis C virus RNA during treatment may provide more precise information of the effectiveness of therapy.

Serological and salivary markers compared with biochemical markers for monitoring interferon treatment for hepatitis C virus infection

Paired serum and saliva specimens were collected on a regular basis from 18 asymptomatic blood donors participating in a controlled clinical trial of interferon alpha 2a (IFN) treatment of chronic hepatitis C virus (HCV) infection. Nine patients were randomised to receive interferon and nine to observation only. Serum and salivary HCV RNA was detected by a "nested" polymerase chain reaction (PCR) assay. Complete follow-up data were available for 14 patients (7 treated and 7 untreated). Serum ALT levels declined to normal in five of the seven IFN-treated patients by the twelfth week. Of these five, loss of hepatitis C viraemia was observed in three. Of the seven treated patients, the three responders had a lower viraemia level than the partial or nonresponders. Both nonresponders had infection with type 1 HCV, but the complete and partial responders were infected with types 2 or 3. HCV RNA was detected in the saliva of all seven observation patients during the follow-up period. HCV was also detected in the saliva of the two patients who did not respond to IFN treatment. No correlation was shown between the level of HCV RNA in serum and the presence of HCV RNA in saliva. A role for noninvasive salivary investigations in monitoring treatment is possible, but further refinement of the methodology is required.