Treatment of chronic hepatitis C with high-dose interferon alpha-2b. A multicenter study

Chronic hepatitis C in patients with normal or near normal alanine aminotransferase levels: the role of interferon alpha 2b therapy

BACKGROUND/AIMS

Interferon is the only approved therapy for chronic hepatitis occurring as a consequence of an infection with the hepatitis C virus. Because interferon is expensive, has a large number of untoward effects and its efficacy is not guaranteed, many physicians limit their use of this therapy to those with histologically advanced but not end-stage cirrhotic disease. Moreover, most cases are biopsied only after 6 months or more of abnormal alanine aminotransferase levels have been documented. The rationale for this approach to patients with hepatitis C virus infection has not been demonstrated.

METHODS

In the present study, a total of 37 patients with alanine aminotransferase levels < 1.5 upper limits of normal (59 IU/l or less) who were HCV-RNA positive by reverse transcriptase polymerase chain reaction, were selected for interferon treatment, having been identified as having hepatitis C virus disease as the result of a screening Ab-HCV test confirmed with a positive radio immune blotting assay. Once identified, each subject underwent a percutaneous liver biopsy and was tested for the presence of HBsAg, Ab-HBs and HBV-DNA. All liver biopsies were read and graded according to the criteria of Knodell et al. Each subject was treated with interferon a2b at a dose of 5 MU administered daily until a response was achieved (a minimum period of 6 months) or until a full year had elapsed. A response was defined as HCV-RNA negativity in serum on three consecutive monthly determinations. The study population consisted of 21 males and 16 females ranging in age from 17 to 72 years (mean 46.7 +/- 2.2 years). Their mean serum alanine aminotransferase level at the initiation of therapy was 37.5 +/- 2.1 IU/l with a range of 10-59 (normal values being 40 IU/l or less). 54% of the subjects were presumed to have acquired their hepatitis C virus infection as a result of a blood transfusion; 32% as a result of prior intravenous drug abuse; and 13% had no identifiable risk factor for hepatitis C virus. Despite having normal or near normal serum alanine aminotransferase levels, 9 subjects had chronic persistent hepatitis, 13 had chronic active hepatitis and 15 had chronic active hepatitis + cirrhosis documented by histopathologic assessment of their liver biopsies.

RESULTS

An interferon response was achieved in 5/9 with chronic persistent hepatitis, 11/13 with chronic active hepatitis and 8/15 with chronic active hepatitis + cirrhosis for an overall response rate of 65%.

CONCLUSIONS

This study has demonstrated that individuals who: 1) are hepatitis C virus positive with serum alanine aminotransferase levels < 1.5 x upper limits of normal can have histologically advanced liver disease; 2) can respond to interferon therapy defined as clearance of detectable HCV-RNA in serum; and, 3) should be considered for interferon treatment.

Interferon alfa-2b for chronic hepatitis C: effects of dose increment and duration of treatment on response rates. Results of the first multicentre Australian trial. Australia Hepatitis C Study Group

Two hundred and thirty patients with histologically proven chronic hepatitis C were randomized to receive one of the following treatment protocols: (a) 3 million units of interferon alfa-2b thrice weekly for 6 months, (b) 5 million units thrice weekly for 6 months, or (c) 3 million units thrice weekly for 2 years. The short-term response to treatment was defined by normal alanine aminotransferase for at least 3 months and until the end of treatment, and was confirmed by loss of hepatitis C viraemia in 42 (91%) of 46 cases as determined by reverse transcription-polymerase chain reaction. Short-term response to interferon alfa-2b was independent of the incremental dose, being 64% for 5 million units and 58% for 3 million units. Long-term response to interferon alfa-2b was defined by continued normality of alanine aminotransferase levels for at least 6 months after treatment withdrawal. The long-term response rates among responders treated for 6 months and those treated for 2 years were 29% and 54%, respectively (p < 0.001). Among all 18 patients tested, serum HCV-RNA was negative at both 6 and 12 months of follow-up in all long-term responders, and none have subsequently relapsed. Improvement in hepatic necroinflammatory changes was confirmed by quantitative histology (Scheuer score) in responders at the end of interferon alfa-2b treatment. The changes were significantly greater among those who had been treated for 2 years compared with those treated for 6 months (p < 0.05 and p < 0.02, respectively, for portal and lobular inflammation scores). Several pretreatment characteristics could be correlated with a favourable response to interferon alfa-2b. Thus, absence of cirrhosis was associated with a short-term response of 75%, while only 42% of patients with cirrhosis had a short-term response (p < 0.001). The frequency of short-term response to interferon alfa-2b also differed according to mode of disease acquisition, being best for injecting drug use (71%), less favourable for blood transfusion (56%) and worst for sporadic cases (43%) (p < 0.01). This observed difference, however, was not independent of histology on multivariate analysis. In summary, a 5 million unit dose of interferon alfa-2b failed to improve the short-term or long-term response to interferon alfa-2b treatment, but prolongation of interferon alfa-2b treatment to 2 years resulted in substantially improved long-term response rate.

Randomized trial comparing three different regimens of alpha-2a-interferon in chronic hepatitis C. The TriVeneto Viral Hepatitis Group

Alpha-interferon (IFN-alpha) is an effective treatment for chronic hepatitis C, but only 20% to 30% of patients are apparently cured with the current recommended schedule of 3 MU given three times a week for 6 months. To evaluate the efficacy of more aggressive treatment regimens, we have conducted a randomized trial in 174 patients with chronic hepatitis C using three different schedules: (1) 12-month treatment starting with 6 MU/ three times a week and decreasing the dose on the basis of serum alanine transaminase (ALT) activities (group A: 59 cases); (2) fixed dose of 3 MU three times a week for 12 months (Group B: 61 cases), (3) fixed dose of 6 MU three times of week for 6 months (Group C: 54 cases). Patients were evaluated during therapy for biochemical and virological response and followed for at least 12 months after therapy to assess long-term efficacy and liver histological outcome. The genotype of infecting HCV was also analyzed in all patients, and predictors of response were determined by multivariate analysis. Serum ALT became normal during therapy in 76% of patients (95% confidence interval [CI]: 63 to 86), 65% (CI: 52 to 77), and 74% (CI: 60 to 85) in groups A, B, and C, respectively (P = NS). The corresponding figures for sustained response 12 months after therapy were 49% (CI: 36 to 62), 31% (CI: 20 to 44), and 28% (CI: 16 to 42)(A vs. B, P = .06; A vs. C, P = 0.03). Eighty-six percent of patients with sustained response cleared HCV-RNA from serum, and 72% improved histologically.(ABSTRACT TRUNCATED AT 250 WORDS)

Quantitation of hepatitis C viral RNA in liver and serum samples using competitive polymerase chain reaction

AIMS

To investigate whether the amount of hepatitis C viral RNA (HCV-RNA) in liver and serum can predict the effectiveness of interferon treatment in patients with chronic hepatitis C.

METHODS

The amount of HCV-RNA in frozen liver tissues and sera of 22 patients with chronic hepatitis C was determined before and after interferon alfa treatment by the competitive reverse transcriptional polymerase chain reaction method.

RESULTS

Patients with small amounts of HCV-RNA in serum before treatment showed a significantly more effective response to interferon treatment. After treatment, HCV-RNA disappeared from both the liver and serum of all patients who sustained complete response (n = 11); in contrast, HCV-RNA decreased but persisted in the liver of all those who relapsed after cessation of treatment (n = 11).

CONCLUSIONS

The elimination of hepatitis C virus from the liver as well as from the serum seems to be essential for sustained remission. The quantitation of HCV-RNA in liver biopsy specimens obtained after treatment would be a highly accurate predictor of whether relapse is likely to occur.

Randomized controlled trial of recombinant interferon-alpha 2b in the treatment of Chinese patients with chronic hepatitis C

To evaluate the efficacy of recombinant interferon (IFN) alpha 2b in the treatment of Chinese patients with chronic hepatitis C, a randomized controlled trial was conducted in 50 chronic hepatitis C patients: 25 patients received 3 million units of subcutaneously injected recombinant IFN-alpha 2b three times per week for 6 months, and 25 patients received no specific treatment were used as controls. At the end of the IFN treatment, 19 patients (76%) in the IFN-treated group normalized serum ALT compared with only 6 patients (24%) in the control group (p < 0.01). Relapse within 6 months after the completion of treatment occurred in 13 IFN-treated patients (68%). Normalized serum ALT was seen in 6 patients (24%) in the IFN-treated group and 1 patient (4%) in the control group 6 months after discontinuation of IFN therapy (p = 0.10). The presence of serum hepatitis C virus (HCV) RNA measured by reverse transcription-polymerase chain reaction was detected at the end of the IFN treatment in all 13 patients who relapsed after cessation of therapy. In only 3 of 25 IFN-treated patients (12%) was the presence of serum HCV RNA not detectable at the end of the IFN treatment or 6 months after cessation of therapy. No patient in the control group had undetectable serum HCV RNA during the study period. Using multivariate logistic regression analysis, the low pretreatment levels of HCV RNA, measured by a quantitative branched DNA amplification assay, was the only independent predictor of a sustained response to IFN therapy (p = 0.02).(ABSTRACT TRUNCATED AT 250 WORDS)

Comparative study of two high doses of lymphoblastoid interferon in the treatment of chronic hepatitis C: influence on the levels of ALT, viraemia and histologic activity

Ninety consecutive patients with chronic hepatitis C were included in a randomized, uncontrolled trial to compare the efficacy of two treatment regimens, 10 MU (group A) vs 5 MU (group B), of lymphoblastoid interferon, in a step-down schedule for 24 weeks. All of the patients had antibodies against the hepatitis C virus, and all but one were HCV RNA positive in serum. The origin of the infection was attributed to blood transfusion in 30 patients and classified as sporadic in 60 patients. During treatment reduction in the ALT levels as well as the elimination of viraemia was observed in both treated groups, although these changes did not correlate significantly with the interferon dose. Nine months after the end of therapy, a sustained response was achieved in 13.6% (12/88) of the patients. Relapse in group B (87.5%) was significantly higher than in group A (59.1%). The percentage of cases which remained with undetectable HCV RNA was significantly higher for the sustained responders (66.7%) than for the non-responders (11.8%) and relapser patients (2.4%). Repeated liver biopsies showed an overall significant reduction of all the subindices of histological activity from patients with sustained response, except for fibrosis. In short: the 10 MU dosing regimen of lymphoblastoid interferon was as efficient as the 5 MU dose as it brought about a similar improvement in ALT levels, histological activity and elimination of viraemia, albeit 10 MU proved significantly more effective in the prevention of a relapse among the responders after 24 weeks therapy.

Usefulness of simple assays for serum concentration of hepatitis C virus RNA and HCV genotype in predicting the response of patients with chronic hepatitis C to interferon alpha 2a therapy

The use of two new assays was evaluated for predicting the response to interferon (IFN) therapy in patients with chronic hepatitis C. The genotype of hepatitis C virus (HCV) was established by an enzyme-linked immunosorbent assay based on genotype-specific recombinant peptides of the NS4 region (genotyping ELISA). The concentration of HCV RNA was measured by a branched DNA assay (bDNA assay). Seventy-eight patients received the same regimen of IFN alpha 2a. Of the 74 patients assessed who completed the program, 38 (51.4%) were responders; i.e., their serum aminotransferase levels remained normal for 6 months or longer after stopping IFN, while 36 (48.6%) were nonresponders. The results of the HCV genotype determined by the genotyping ELISA and by the polymerase chain reaction (PCR) assay based on genotype-specific primers were similar. The serum concentrations of HCV RNA as measured by the bDNA assay and by the competitive PCR assay correlated closely and significantly (r = 0.82, P < 0.001). Multiple logistic regression analysis showed that the serum concentration of HCV RNA determined by the bDNA assay, the HCV genotype determined by the genotyping ELISA, and the histology activity index (HAI) of the liver were independently associated with IFN efficacy. By using these three variables in combination, a predictive rate of 82.4% was obtained. A lower level of HCV RNA, genotype 2 and a lower HAI score for liver histology were predictive of a favorable response to IFN. Thus, the genotyping ELSIA and the bDNA assay appear to be useful for clinical management of patients receiving IFN therapy.

Long term follow-up and patterns of response of ALT in patients with chronic hepatitis NANB/C treated with recombinant interferon-alpha

The response to interferon treatment in chronic hepatitis NANB/C has usually been classified as complete, partial or absent, according to the behavior of serum alanine aminotransferase (ALT). However, a more detailed observation of the enzymatic activity has shown that the patterns may be more complex. The aim of this study was to describe the long term follow-up and patterns of ALT response in patients with chronic hepatitis NANB/C treated with recombinant interferon-alpha. A follow-up of 6 months or more after interferon-alpha was achieved in 44 patients. We have classified the serum ALT responses into six patterns and the observed frequencies were as follows: I. Long term response = 9 (20.5%); II. Normalization followed by persistent relapse after IFN = 7 (15.9%); III. Normalization with transient relapse = 5 (11.9%); IV. Temporary normalization and relapse during IFN = 4 (9.1%); V. Partial response (more than 50% of ALT decrease) = 7 (15.9%); VI. No response = 12 (27.3%). In conclusion, ALT patterns vary widely during and after IFN treatment and can be classified in at least 6 types.

Predictors of sustained response, relapse and no response in patients with chronic hepatitis C treated with interferon-alpha

Three main patterns of response are seen when interferon-alpha (IFN-alpha) is used for the treatment of chronic hepatitis C: 1 sustained response with alanine-aminotransferase (ALT) normalization that is maintained after cessation of therapy, with or without clearance of serum hepatitis C virus (HCV) RNA; 2 transient response with ALT normalization during therapy followed by relapse after its withdrawal, and 3 no response with no or only partial reduction in ALT levels. In order to define variables that could predict each of these three types of response we studied 321 cases of chronic hepatitis C treated with IFN-alpha in two consecutive trials conducted in our Unit. By univariate analysis, age < 45 years (P < 0.01), known disease duration < 60 months (P < 0.01), normal gamma-glutamyl-transpeptidase (gamma GT) levels (P < 0.01) and infection by HCV genotype 2 or HCV genotype 3 (P < 0.01) were found to be statistically associated with sustained response while age > 45 years (P < 0.01), body weight (P = 0.05), cirrhosis (P < 0.01) and elevated gamma GT levels (P < 0.01) were associated with no response. By multivariate analysis sustained response was predicted by HCV genotype 2 (P < 0.01) and HCV genotype 3 (P < 0.01), known disease duration (P < 0.01), patient's age (P < 0.05) and associated with the use of a more aggressive treatment schedule (P < 0.05). Transient response with relapse was predicted by known duration of disease (P < 0.05), HCV genotype 1 (P < 0.05) and female sex (P < 0.05). No response was statistically associated with elevated gamma GT levels (P < 0.01), higher body weight (P < 0.05) and with the less aggressive regimen of 3 MU of natural IFN-alpha given three times weekly for 6 months (P < 0.05). These results indicate that the HCV genotype as well as the schedule of treatment greatly affect the pattern of response to IFN in chronic hepatitis C and allow us to define criteria to predict which type of response is more likely in individual patients.

Clinical and histologic predictors of response to interferon-alpha in patients with chronic hepatitis C viral infection

To evaluate if any pretreatment characteristics of patients with chronic hepatitis C (HCV) can be used to predict response to the current recommended dose (3 million units three times a week) and higher doses of interferon-alpha (IFN), we retrospectively assessed the response of 37 patients with HCV who were treated with IFN. Sixteen patients (43%) responded to the standard dose of IFN with normalization of ALT. Weight and liver histology were found to be significant factors for response. The responders weighed significantly less than nonresponders (161.8 +/- 35.5 lb versus 200.3 +/- 45.4 lb, P = 0.008). Seventy-five percent of patients with chronic lobular or persistent hepatitis were responders, whereas only 28% of patients with more advanced hepatitis responded (P = 0.01). There was no correlation between the degree of bile duct damage or steatosis and response rate. This study suggests that obesity and severe histologic injury are negative predictive factors of response to the current recommended dose of IFN. The adequacy of the current recommended dose of IFN in overweight patients needs to be investigated.

Hepatitis C: progress and problems

The hepatitis C virus (HCV), a single-stranded RNA virus, is the major cause of posttransfusion hepatitis. HCV isolates differ in nucleotide and amino acid sequences. Nucleotide changes are concentrated in hypervariable regions and may be related to immune selection. In most immunocompetent persons, HCV infection is diagnosed serologically, using antigens from conserved regions. Amplification of RNA may be necessary to detect infection in immunosuppressed patients. Transmission by known parenteral routes is frequent; other means of spread are less common and may represent inapparent, percutaneous dissemination. Infection can lead to classical acute hepatitis, but most infected persons have no history of acute disease. Once infected, most individuals apparently remain carriers of the virus, with varying degrees of hepatocyte damage and fibrosis ensuing. Chronic hepatitis may lead to cirrhosis and hepatocellular carcinoma. However, disease progression varies widely, from less than 2 years to cirrhosis in some patients to more than 30 years with only chronic hepatitis in others. Determinants important in deciding outcome are unknown. Alpha interferon, which results in sustained remission in selected patients, is the only available therapy. Long-term benefits from such therapy have not been demonstrated. Prevention of HCV infection by vaccination is likely to be challenging if ongoing viral mutation results in escape from neutralization and clearance.

The role of interferon in the treatment of viral hepatitis

Chronic viral hepatitis, frequently an asymptomatic disease, can persist for decades. Despite the lack of symptoms, prolonged infection can lead to the complications of cirrhosis, liver failure and hepatocellular carcinoma. The goal of therapy is to reduce the risk of developing these complications and to eradicate the infectious pool. Patients with ongoing viral replication appear to be at greatest risk for developing complications. These patients have been targeted for treatment. Numerous randomized studies of interferon treatment of chronic hepatitis B and C have been published in the last 8 years. The experience from these studies and more recent developments will be reviewed.

Interferon therapy in chronic hepatitis C virus infection

Antiviral treatment of chronic hepatitis C with interferon is reviewed. Alpha-interferon, both recombinant alpha-2a, -2b and human lymphoblastoid interferon given at a dose of > or = 3MU t.i.w. for 6-12 months will result in normalisation of ALT levels (complete response) in some 50-60% of treated patients with chronic hepatitis C virus (HCV) infection. Approximately half of the complete responders to interferon will relapse within 6 months once treatment is withdrawn (non-sustained response). Longer treatment schedules (6 vs. 12 months) seem to diminish the relapse rate and increase the percentage of sustained response. In patients with sustained response to interferon treatment with continuously normal ALT levels > or = 6 months after treatment stop a concomitant eradication of the viraemia is usually seen, whereas a non-sustained or non-response to interferon usually will indicate a continuous viraemia. Factors predictive of a favourable response are low pretreatment HCV RNA levels in serum, genotypes other than type II according to Okamoto, short disease duration, female gender and less pronounced liver damage, whereas high serum HCV RNA levels, having genotype II and cirrhosis, are predictive of a less favourable response. Patients with a sustained response and eradication of the viraemia will also improve their liver inflammation with diminishing scores for portal inflammation, piecemeal necrosis, lobular inflammation and also fibrosis after treatment. For non-responders and non-sustained responders to interferon, ribavirin especially in combination with interferon will offer some hope for the future.

Treatment of chronic sporadic-type non-A, non-B hepatitis with lymphoblastoid interferon: gamma GT levels predictive for response

The aim of this study was to evaluate the efficacy of human lymphoblastoid interferon-alpha treatment in chronic sporadic-type non-A, non-B hepatitis. We also aimed to determine if histological or liver function data could predict either response or relapse. Sixty patients with chronic sporadic-type non-A, non-B hepatitis were randomized in two groups of 30. One group was treated with interferon-alpha (3 MU thrice weekly) for one year; the other group was untreated controls. The treated group was followed for another year after interferon withdrawal. Liver function tests were performed during treatment. Liver biopsy was carried out before and a year after randomization. We evaluated rate of response [normalization of alanine aminotransferase (ALT) levels for at least three consecutive months] and rate of relapse (ALT rebound after therapy suspension). We also looked at possible predictive factors for response and relapse. In the treatment group the rate of response was 55% (16/29). No control patient exhibited ALT normalization. Among the responders, 31% (5/16) relapsed after interferon withdrawal. Low gamma GT and female sex are positive predictive factors of response (P < 0.01 and P < 0.02 respectively). Presence of portal and periportal inflammation at the second liver biopsy was correlated with relapse (P < 0.05). In conclusion, human lymphoblastoid interferon-alpha treatment for one year is beneficial in patients suffering from chronic sporadic-type non-A, non-B hepatitis. Low pretreatment gamma GT levels and female sex are positive predictors of response in this patient population.(ABSTRACT TRUNCATED AT 250 WORDS)