The most relevant randomized controlled trials of interferon-alpha (IFN) for naive patients with chronic hepatitis C (CHC) published in a decade, just before appearance of pegylated IFN trials in 2000, were included in this paper. Its purpose is to review the relationship between sustained biochemical response in active versus control group versus usual clinical variables as IFN regimens, cirrhosis, genotype and versus less frequently addressed variables as funding, methodological quality or location of principal author. Meta-analysis estimates of global treatment effect varied according to trial design: group 1=IFN versus placebo/no treatment, 32 RCTs, 2499 pts, OR 9.5 (6.3-14.2); group 2a=comparison of IFN schedules, 43 RCTs, 7454 pts, OR 1.6 (1.4-1.9); group 2b=IFN+other drugs versus standard IFN, 30 RCTs, 4737 pts, OR 2.0 (1.6-2.6). Fixed effects (arm-level) meta-regression on the complete data set (171 arms, 10,580 pts) revealed that sustained response was most likely in experimental arms of IFN+ribavirin or other drugs (OR 2.4), arms using yearly schedule (OR 2.0), trial principal author from Asia (OR 1.7), trial sample size >200 (OR 1.4) and arms enrolling less than 50% of cirrhotics (OR 1.3). Moreover, focus was on some significant interactions too, as the effect of trial's quality interacting to the recorded funding (more benefit if no-profit, less if for-profit) and the effect of trial funding interacting to the location of first author (more benefit if from Asia). Three main effects (experimental arm, cirrhosis, funding) and one interaction (funding*location of principal author) explained 31% of between study variability in a random-effect meta-regression. In a subgroup analysis on a data set including available information on HCV genotype (93 arms, around 7000 pts), meta-regression revealed that genotype 1 or 4 less than 50% per arm and specialistic journal were significant predictors of either biochemical (transaminases) or virological (HCV-RNA) sustained response, in a model including the same main effects identified in the complete data set analysis. Finally, although mostly captured by different IFN regimens along time, heterogeneity of effect in a large set of (not-pegylated) IFN trials was also explained by HCV genotype and variables of quality and reporting, such as trial's principal author from Asia.

The long-term histological and virological outcomes of spontaneous circulating hepatitis C virus (HCV) clearance were studied in chronic liver disease. Between 1979 and 1984, three patients underwent laparoscopy for chronic non-A, non-B liver disease, and two were found to have cirrhosis and one with chronic active hepatitis. After HCV assays became available in 1990, they were positive persistently for HCV antibody without serum HCV RNA. Reductions of antibody levels to HCV core and/or nonstructural proteins were observed, and liver biopsies were undertaken between 1995 and 2000. Liver biopsies at 11-19 years after laparoscopy disclosed marked alleviation of liver inflammation and fibrosis in each case although a low grade of inflammation remained. The two patients with cirrhosis no longer showed histological features of cirrhosis, and the poor liver function in one patient had been ameliorated. Liver specimens from two patients were subjected to polymerase chain reaction to detect positive and negative HCV RNA strands and hepatitis B virus DNA. Only the positive HCV RNA strand was detected for one patient who had previously cirrhosis. Liver specimens were examined from another six nonviremic HCV-seropositive individuals without chronic liver disease. Five patients displayed low-grade liver inflammation without evident fibrosis, but none had any viral genome in the liver. These findings suggest that spontaneous circulating HCV clearance in chronic liver disease confers favorable liver histological outcome, although occult HCV infection persists. J. Med. Virol. 69:41-49, 2003.

A previous meta-analysis of interferon therapy in naive patients with chronic hepatitis C has documented its efficacy in achieving virologic clearance, and improving liver biochemistry and histology; however, since its publication additional trials have been reported.

To evaluate the response to interferon in interferon naive patients with chronic hepatitis C. The effect of treatment dose and duration, and the response in patients with cirrhosis and those with normal aminotransferases was also investigated.

The Cochrane Controlled Trials Register (Cochrane Library Issue 1, 1999), MEDLINE (January 1966 to December 1999), and reference lists were searched, and pharmaceutical companies were contacted for unpublished trials.

Randomised clinical trials comparing interferon with placebo, no treatment, or different regimens of interferon were selected. Abstracts were excluded.

The primary outcome measure was sustained disappearance of serum HCV RNA (virologic sustained response (SR)). Biochemical and end of treatment responses, liver histology, and adverse events were also recorded. Assessment of drug efficacy used the methods of Peto and Der Simonian and Laird.

Fifty-four trials enrolling 6545 patients were included. Compared with no treatment, interferon 3 MU thrice weekly for 12 months increased the probability of a virologic SR (Peto odds ratio (OR) 4.60; 95% confidence interval (CI) 1.53 to 13.85). At this dosage and duration of therapy, the rate of virologic SR was 17% (95% CI 10 to 28%) in interferon-treated patients versus 3% (95% CI 1 to 10%) in controls. A dose of 6 MU was more effective than 3 MU thrice weekly (OR for 12 months treatment, 2.21; 95% CI 1.10 to 4.45), as were durations of 12 months or greater versus six months (OR 1.87; 95% CI 1.30 to 2.67). Adverse events were more common with higher doses and prolonged durations of treatment. Compared with no therapy, interferon increased the probability of histologic improvement (OR 9.22; 95% CI 5.69 to 14.94). The response to interferon in cirrhotic patients (virologic SR, 17%; 95% CI 11 to 26%) was similar to that in non-cirrhotic patients. However, interferon was no more effective than control in patients with normal aminotransferases.

Interferon is effective in achieving viral clearance and improving liver biochemistry and histology in interferon naive patients with chronic hepatitis C. Higher doses and prolonged durations are more effective, but associated with more frequent adverse events. Interferon is associated with similar benefits in patients with cirrhosis, but the efficacy in patients with normal aminotransferases is unproven.

The outcome of HCV infection is determined by the interaction between the virus and the host immune system. The persistence of infection in most HCV-infected individuals, despite the presence of HCV-directed antibodies, suggests that such antibodies fail to induce viral clearance. Patients with self-limited hepatitis C have evidence of a polyclonal, multispecific CD8+ T-cell response along with a coordinated CD4+ T-cell response that is associated with eradication of HCV infection. Cytokines are produced both locally within the liver and systemically and may play an important role in controlling viral replication and contributing to hepatocellular damage through amplification of a nonspecific immune response. In most patients, the humoral, cellular immune, and cytokine response seem insufficient to eradicate infection. In its attempt to clear the virus from the liver, the immune system contributes to the hepatocellular injury seem in most chronically infected patients. A better understanding of the host's immune response may provide further insight on the pathogenetic mechanisms involved in development of chronic hepatitis and aid the development of better therapeutic strategies.

The aim of this study was to update our previous meta-analysis of interferon (IFN) in the treatment of hepatitis C and to analyse new factors, namely, HCV RNA end-point, patients with cirrhosis and patients with normal ALT. We use the Der Simonian and Laird method, with heterogeneity and sensitivity analyses. Seventy-six randomized control trials (RCTs) in naive patients were found but we focused our analysis on 59 RCTs with chronic hepatitis C (26 vs. controls and 33 comparing different regimens) and on seven RCTs in acute hepatitis. Interferon-alpha (IFN-alpha) at 3 MU thrice weekly (TIW) for 12 months exhibited 39% of virological end-of-treatment response (ETR) and 17% of virological sustained response (SR), respectively, vs. 1% and 3% in untreated controls (all P < 0.001). There was a significant dose effect (in favour of 6 vs. 3 MU TIW): the virological SR at 6 months were 35% in the 6 MU group (95% CI: 24-47) and 16% in the 3 MU group (95% CI: 8-27) and were at 12 months 43% in the 6 MU group (95%CI: 31-56) and 25% in the 3 MU group (95% CI: 16-37). There was a significant duration effect (12 vs. 6 months) upon the virological SR rate both at 3 and 6 MU: 3 MU provided 14% of virological SR (95% CI: 11-19) in the 12 months group vs. 7% (95% CI: 5-11) in the 6 months group and 6 MU provided 22% (95% CI: 17-29) and 16% (95% CI: 11-22) virological SR in the 12 and 6 months groups, respectively. Cirrhotic treated patients had 17% of virological SR (95 CI: 9-24%; P < 0.001) vs. 0% in controls and provided a 20% reduction rate (95 CI: -2% to -37%, P=0.03) in hepatocellular carcinoma incidence. In acute hepatitis C, a 3-month treatment with IFN-alpha showed significant efficacy vs. controls upon the virological SR rate (32% vs. 4%, P < 0.001). In conclusion, we confirm the dose and duration effect of IFN in chronic hepatitis C, and the efficacy of IFN-alpha in the treatment of acute hepatitis and in cirrhotic patients.

A long-term assessment of quantitative hepatitis C virus (HCV) testing was performed at the University of Pittsburgh Medical Center. The Quantiplex HCV RNA 2.0 branched-chain DNA (bDNA) assay (Bayer Diagnostics) for hepatitis C viral load determination was used to test 3,471 specimens. bDNA-negative samples were also tested by an in-house qualitative reverse transcriptase (RT)-PCR assay with a measured sensitivity of fewer than 100 HCV genome equivalents per milliliter. Of 1,239 bDNA-negative specimens, 74.1% were negative and 25.9% were positive by RT-PCR, indicating the presence of viremia in a significant proportion of bDNA-negative samples. We discuss the medical and economic implications of these results and propose two alternatives for clinical laboratories to consider in approaching quantitative HCV testing. For laboratories able to perform a sensitive RT-PCR assay for </=40% of the bDNA test cost, prescreening bDNA requests by RT-PCR may be the most cost-effective approach.

The effectiveness of interferon against hepatitis C has been found to be greatly affected by viral factors. However, few controlled interferon trials have involved seemingly intractable cases of chronic hepatitis C.

In 44 patients with high hepatitis C virus RNA levels (> or = 10(5) copies/mL), we carried out a prospective, controlled study of two natural interferon-alpha regimens, seeking predictors of therapeutic efficacy. Total natural interferon-alpha doses over 6 months in two groups were 780 and 840 million units, respectively.

High therapeutic efficacy was achieved with no significant outcome difference between the regimens. The virus eradication rate was 35% and the rate of sustained biochemical response was 45% for both regimens. Multivariate logistic regression analysis identified viral genotype as the only significant predictor of success in viral eradication.

Hepatitis C virus genotype 2 showed high sensitivity to interferon-alpha and this therapy can be recommended even for patients with a high viral load of this genotype. In contrast, with genotype 1b, cure was extremely difficult in cases with 10(7) or more copies/mL with a single 6-month course of interferon-alpha.

The purpose of this study was to evaluate the clinical usefulness of surrogate markers of the interferon effect (i.e., alanine aminotransferase levels and serum HCV-RNA status) as predictors of long term response, and to identify the optimal schedule of treatment for patients with chronic hepatitis C by means of meta-analysis.

Pertinent randomized clinical trials and prospective studies were selected using MEDLINE (1986-1996), a reference list from published articles or reviews. Twenty-six prospective studies reporting data on surrogate markers of interferon response were selected. Thirty-nine trials comparing interferon alpha to no treatment and 25 trials comparing different schedules of interferon were reviewed. Conventional meta-analysis according to the DerSimonian and Laird method was used for the pooling of results.

The pooled probability of late relapse among sustained responders with negative serum HCV-RNA 6 months after treatment was very low (8.7%; 95% confidence interval 5.8-11.6%). The overall risk difference between treated and control groups was 16.63% (95% confidence interval 11.95-21.31%) for sustained aminotransferase normalization. Therapy with higher interferon dose compared with standard dose significantly improves the rate of sustained response (pooled risk difference 10.56%, 95% CI 5.47-15.65%). Cumulative meta-analyses suggest that a clear dose-response relationship exists across a wide range of interferon dosages. The multivariate meta-regression model confirms that the total interferon dose is an independent predictor of sustained response and that it seems more important than the length of treatment.

Testing for serum HCV-RNA, 6 months after interferon therapy in sustained biochemical responders, is useful for predicting long term response. The current standard total interferon dose of 234 mega-units is suboptimal. Further trials that directly compare different schedules of treatment are needed.

Hepatitis C virus (HCV)-RNA status and alanine aminotransferase (ALT) levels determined shortly after interferon (IFN) therapy in patients with chronic hepatitis C do not predict long-term response. To determine the virological sustained response after the completion of IFN therapy, HCV-RNA was measured at the end of treatment and at 3-4 months and 12 months after the completion of therapy in 537 patients with chronic hepatitis C. In 347 patients, HCV-RNA was not detected by polymerase chain reaction (PCR) at the completion of therapy and 175 of these patients (50%) were still PCR negative 12 months later. In contrast, of the 180 patients who were HCV-RNA negative at 3-4 months after completion of therapy, 99% remained negative at 12 months. Normal ALT levels were found in 80, 93 and 95% of patients who were negative for HCV-RNA either at the end of treatment or at 3-4 months and 12 months after the completion of therapy, respectively. Of patients who were HCV-RNA positive, 30, 15 and 20% were found to have normal ALT levels at the same respective time points. To determine a sustained virological response shortly after the completion of therapy, serum HCV-RNA was serially examined in 66 patients negative for HCV-RNA at the end of therapy. Of 31 patients who relapsed, HCV-RNA reappeared in 33, 80, 97 and 100% of patients by 1, 2, 4 and 8 weeks after the completion of therapy. In conclusion, a sustained virological response could be determined with 97 and 99% certainty at 4 weeks and at 3-4 months after the completion of therapy, respectively.

We have assessed the predictive value of the grade of pretreatment liver lesions on histologic response to interferon therapy in patients with chronic hepatitis C. In 93 patients with chronic hepatitis C virus (HCV) infection who showed an initial response to interferon therapy, HCV RNA load and serum aminotransferase levels together with grade of liver histologic lesions were assessed at baseline and 6 months after treatment cessation. Regression of portal and periportal necroinflammation was observed only in sustained responders (normalization of aminotransferase levels and HCV RNA clearance). Neither short-term response nor the absence of virus was associated with significant histologic changes in the liver biopsies. Logistic regression analysis showed that pretreatment histologic lesion was an independent predictive factor of biologic response in the histologic regression of lesions 6 months after cessation of interferon treatment. In conclusion, a dense inflammatory necrotic activity is a positive predictor of histologic response in interferon-treated patients with HCV.

We investigated the efficacy and tolerability of three different types of interferon-alpha, administered with the same schedule to naive patients with chronic hepatitis C. One hundred and seven patients with histologically proven chronic hepatitis C were enrolled during a period of three years and randomly divided into three groups, to receive (a) leukocyte-interferon-alpha, 6 MU three times a week for 4 months, followed by 3 MU three times a week for 8 months (Group I); (b) recombinant-IFN-alpha-2a, with the same schedule (Group II); and (c) lymphoblastoid-IFN-alpha-N1, with the same schedule (Group III). All patients were followed-up for 6 months to evaluate the long-term response. The 'Complete Response' rates at the end of treatment were: 50%, 46.1% and 41.6%, in Groups I, II and III, respectively; most patients relapsed after the end of therapy, so that the 'sustained responders' were, after 6 months of follow-up, 18.7%, 23.1% and 19.4%, respectively. Analysis of pre-treatment variables showed that age, ALT and gamma GT serum levels, as well as the prevalence of liver cirrhosis, were lower in the 'sustained responder' group. Four patients were eliminated from the study because of severe adverse events: 1, 2 and 1, in Groups I, II and III, respectively. Our results indicate a similar response rate with the three different types of interferon-alpha, although at baseline, age, serum levels of gamma globulins and the number of patients with cirrhosis-possible negative-risk factors, were higher in Group I.

There are limited data on the use of high interferon (IFN) dosage for treatment of children and young adults with hepatitis C virus infection and in those affected by thalassemia major (TM).

To assess the response of children and young adults with chronic hepatitis C disease, including those affected by TM, to high dose natural alpha-interferon (IFN-alpha). To evaluate the effect of iron overload in response to high dose IFN-alpha in young chronic hepatitis C virus thalassemia patients.

We conducted a therapeutic trial of natural IFN-alpha, using 10 million units/m2 three times a week for 6 months in 14 chronic hepatitis C patients ages 5 to 28 years; 7 also had TM. The follow-up period lasted 12 months.

Ten patients (73%) showed normal or nearly normal alanine aminotransferase values at the end of follow-up (biochemical response), but only five (35%) were negative for serum hepatitis C virus-RNA (complete responders). Four of the patients (57%) with TM were sustained complete responders. No correlation was found between the initial serum concentration of ferritin and response to IFN therapy. Patients infected with genotype 1b showed a poor response although high dose of natural IFN was used.

These results indicate that IFN-alpha can be used in children and young patients with chronic hepatitis C disease as well as in those affected by TM. Treatment with high dosage natural IFN-alpha in children and young adults with hepatitis C infection does not appear to be more effective than dosages previously used.

Multiple factors may influence the host-virus interaction in patients infected with hepatitis C virus (HCV), and these may result in diverse disease presentations. In immune competent hosts, there is little evidence that direct cytopathicity plays a significant role in liver cell injury. However, when host conditions are altered to allow for unusually high levels of viral replication and viral protein expression (i.e., immunosuppression), HCV may induce direct hepatocellular damage. In most patients infected with HCV, a wide array of humoral and cell-mediated immune responses are triggered in response to HCV polypeptides; however, despite this host immune response, HCV infections usually persist. Furthermore, the host immune response, in its attempt to clear the virus from the liver, contributes to the hepatocellular damage (chronic hepatitis) seen in the majority of chronically infected patients.

We studied the levels of serum hepatitis C virus (HCV)-RNA, the HCV genotype before interferon therapy, and the kinetics of serum HCV-RNA at the initial stages of therapy to determine their utility in predicting the therapeutic efficacy of interferon in 44 patients with chronic hepatitis C infection. We also looked at the efficacy of repeated interferon treatment in relation to the kinetics of serum HCV-RNA. The level of serum HCV-RNA determined by a branched DNA probe assay before interferon treatment and that by a reverse transcription nested polymerase chain reaction assay during the initial stages of interferon administration were useful for predicting the efficacy of treatment. Furthermore, detection of serum HCV-RNA by the reverse transcription nested polymerase chain reaction assay after the completion of interferon therapy indicated relapse at its earliest stage. In patients who experience relapse, repeated treatment with an appropriate dose of interferon before an increase in viral levels may increase the proportion of complete responses.

Interferon therapy has a beneficial effect in patients with chronic hepatitis C who have a low viral load. The aim of this study was to compare the core protein level with HCV RNA levels and to analyze whether virus quantitation predicts the efficacy of interferon therapy.

HCV core protein level assessed by the recently developed assay was compared with HCV RNA levels measured by three different methods (Amplicor-HCV monitor, competitive RT(CRT)-PCR, and bDNA probe assay) in 352 patients with chronic hepatitis C in relation to viral serotype.

From 91% (320/352) to 93% (299/322) of patients with viremia were detected by Amplicor-monitor and CRT-PCR, in contrast to 60% (187/312) and 74% (191/258) by bDNA and HCV core protein assay, respectively. The HCV core protein level was positively correlated with HCV RNA levels measured by the three assays (r = 0.680 to 0.731). Serum HCV RNA and core protein levels were significantly lower in patients with serotype 2 than in those with serotype 1. Viral eradication after interferon therapy was observed in 60-70% of the patients with < 1 x 10(4) copies/ml of HCV RNA by Amplicor-monitor assay, < 2 x 10(5) copies/ml by CRT-PCR, < 0.5 Meq/ml by bDNA assay, and < 20 pg/ml of core protein by HCV core protein assay. Viral eradication was uncommon (< 11%) among the patients with higher viral loads. Bivariate analysis revealed that the outcome of interferon therapy was more closely associated with both HCV core protein and RNA levels than the HCV serotype.

Quantitation of HCV core protein and HCV RNA in useful for prediction of the interferon response.

To evaluate the histological changes seen in liver biopsies after interferon (IFN) treatment in patients with chronic hepatitis C and human immunodeficiency virus (HIV) infection.

Twenty four intravenous drug users with chronic hepatitis C were investigated histologically before beginning a 12 month course of IFN treatment and 18 months later. Twelve were HIV positive, without opportunistic or other viral infections (group A), and 12 were HIV negative (group B).

According to alanine amino-transferase concentrations, four sustained responders and eight non-responders were found in group A; six sustained responders, five relapsers, and one non-responder were found in group B. HCV RNA became negative in one sustained responder of group A and in the six sustained responders of group B. When histological findings of biopsies performed before therapy and 18 months later were compared, no significant changes in the mean value of Knodell's index and subindices were found in group A, whereas in group B Knodell's index, piecemeal necrosis, and focal hepatocellular necrosis decreased significantly.

In chronic hepatitis C, coinfection with HIV showed a tendency towards a lower response to IFN, although this did not reach statistical significance; however, none of the HIV positive patients developed cirrhosis during the follow up and this should be considered in clinical management of such patients.

To examine the effect of prolonged treatment with different doses of interferon alpha-2b on the relapse rate in patients with chronic hepatitis C.

One hundred and seventy-one patients with non-cirrhotic chronic hepatitis C were enrolled in an Italian multicenter trial. All patients were treated for 3 months with 3,000,000 Units (3 MU) of interferon alpha-2b given subcutaneously three times a week (t.i.w.). Patients with abnormal alanine aminotransferase (ALT) values were given 6 MU of interferon for an additional 3 months. If ALT remained persistently abnormal, therapy was then suspended. If ALT levels were normal, therapy was continued (6 MU t.i.w.) for an additional 18 months (total=2 years). Patients with normal ALT were randomly assigned to two groups, one receiving 3 MU and the other receiving 6 MU t.i.w. for an additional 21 months (total=2 years). Follow-up continued for 2 years after therapy withdrawal.

Seven patients stopped treatment during the first 3 months. Of the remaining 164 patients, 76 (46%) showed abnormal ALT levels after 3 months of therapy: 11 of these (14%) normalized ALT values when given 6 MU and a sustained response was maintained in eight during the follow-up. Overall, 54 and 34 patients were allocated respectively to the groups receiving the 3 MU and 6 MU long-term treatment. At the end of therapy, 35/54 patients of the group 3 MU and 21/34 patients of the group 6 MU showed normal ALT levels (65% vs 62%, p=N.S.). After 2 years of follow-up, 24/35 (69%) patients of the group 3 MU and 16/21 (76%) of the group 6 MU were still in remission (p=N.S.). In an intention-to-treat analysis, 48/171 (28%) patients showed a long-term response (normal ALT values, HCV-RNA negative). About 65% of the sustained responders showed low baseline viremia compared with 33% of non-responders (p=0.005) while genotype 1b was more frequently found among non-responders than in long-term responders (84% vs 25%, p=0.0001).

About 14% of patients who do not respond to a 3-month course of 3 MU of interferon normalize ALT levels when given 6 MU. In prolonged treatment, there is no significant difference between 3 and 6 MU in inducing a sustained response. Patients with low baseline viremia and genotype 2a respond significantly better to prolonged interferon therapy than highly viremic patients with genotype 1b.

Several randomized clinical trials of interferon in chronic hepatitis C have examined the histological changes in paired biopsy specimens. We have attempted a quantitative evaluation by meta-analysis.

Randomized Clinical Trials found by MEDLINE search were included if: a) they compared different IFN regimens with non-active treatment or with each other, b) they obtained biopsies before starting and at the time of stopping IFN in a sizable proportion of the treated and control patients, and c) they assessed the biopsy-specimens semi-quantitatively according to Scheuer's numerical scoring system or Knodell's Histological Activity Index, with quantitation of fibrosis and of lobular, portal and periportal necroinflammation.

Seventeen trials were identified, in which 1223 adult patients had been studied. All trials homogeneously pointed towards a favorable interferon effect. The pooled data show a statistically significant histological improvement in treated patients as compared with controls for each of the four Histological Activity Index components and for the total Histological Activity Index score (overall improvement was -0.82 in favor of interferon, p<0.0001, 95% Confidence Interval -1.25 to -0.40). In the ten trials reporting histological changes separately in biochemical responders (primary and sustained responders) and non-responders, histological improvement was confined to the subset of biochemical responders. No change or very little change occurred in non-responders.

Interferon treatment in chronic hepatitis C significantly improves liver histology. The effect of interferon is closely related to biochemical response. Studies assessing histological outcome 1 year or more after interferon treatment in long-term responders and comparatively in non-responders or relapsers would be important to confirm the regression of the necroinflammatory process in the former, as suggested by the normal serum alanine aminotransferase levels.

The purpose of this review is an update of the therapy of hepatitis C especially with Interferon-alpha. From the large number of publications on this topic the established facts were worked out. Taking these facts as a base guidelines for the therapy in practical use were defined. In addition the aspects of therapeutic strategies of chronic hepatitis C which until now can not definitely be judged are discussed. In the relatively few patients in whom hepatitis C is diagnosed already in the acute phase, Interferon-alpha-treatment (3 x 3 million units 3 times a week) for 3 to 4 months increases the percentage of patients in whom HCV-RNA in the serum is eliminated. In patients with chronic hepatitis C, after decision finding for treatment, a standard scheme is recommended which consists of a monotherapy with recombinant Interferon-alpha. The dosage of Interferon-alpha is in the first 12 to 16 weeks 5 up to 6 million units given 3 times a week. For the further therapy 3 million units 3 times a week seems to be appropriate. The recommended duration of Interferon-alpha-therapy is 12 months. A long-term benefit of about 20% can be achieved in unselected groups of patients when judged on the permanent normalisation of serum transaminases and elimination of HCV-RNA in the serum. Important factors which may influence the probability of a sustained response, like HCV genotype, virus titer in serum, duration of the disease, high hepatic iron content and the presence of cirrhosis, are discussed. Up to now there exist no reliable guidelines in the case of a "no change" situation and for patients with a flare-up of inflammatory activity during or after therapy. Combination therapy of Interferon-alpha with other drugs like analogous of nucleotides (for example ribavarin), non steroidal antirheumatic drugs and ursodesoxycholic acid (UDCA) have still to be evaluated in controlled clinical trials.

In chronic hepatitis C virus (HCV) infection, the rate of sustained response to interferon is low. We evaluated, in patients responding to a 26-week course of interferon, the effect of high-dose maintenance therapy in preventing relapse. Three hundred and ten patients with chronic HCV infection (38.3% with cirrhosis, 80.6% with HCV type 1) received interferon alfa-2b for 26 weeks (10 MU tiw for 8 weeks, then 5 MU tiw for 18 weeks). One hundred and twenty-four subjects (40%) normalized aminotransferases, and were allocated randomly either to continue on 5 MU tiw for a further 26 weeks (prolonged therapy group: 60 patients) or to stop interferon (brief therapy group: 64 patients). Fifty-two weeks after stopping interferon the overall sustained biochemical response rate was 13.2% (41/310). The number of patients with normal aminotransferases was comparable between the prolonged and brief therapy groups (30% vs. 35.9%, P = n.s.), and the rate of HCV-RNA clearance was similar (48.8% vs. 42.4%, P = n.s.). The timing of posttreatment relapse was not influenced by the duration of therapy. Fifty-nine patients (19%) did not complete therapy due to adverse effects. Multivariate analysis identified four features predicting sustained biochemical response in subjects normalizing aminotransferases under therapy: negative HCV-RNA at end of therapy, normal aminotransferases at 4 weeks of therapy, high baseline aminotransferases, and high baseline platelets. Infection with HCV type 1 was not a significant predictor of response, due to its high prevalence in our population (80.6%). It is concluded that in patients with chronic hepatitis C mostly infected by HCV type 1, a prolonged high-dose interferon course (900 MU over 52 weeks) did not increase the rate of sustained biochemical response and of HCV-RNA clearance in comparison to a brief course (510 MU over 26 weeks).

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.

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.

To compare the long-term effects of brief and prolonged therapy with alpha-n1 interferon for transfusion-associated chronic hepatitis C.

One hundred and sixteen subjects (male/female 48/68, mean age 46.9 years) were studied. Sixty patients were randomised to brief treatment (group 1: interferon 5 Mu/msq. t.i.w. for 2 months, then 3 Mu/msq. t.i.w. for 4 months), and 56 to prolonged treatment (group 2: interferon 5 Mu/msq. t.i.w. for 2 months, then 3 Mu/msq. t.i.w. for 10 months). All were followed for 12 months after stopping interferon.

The early response rate was 47.4% (Group 1 [45%], Group 2[50%]. No "breakthrough" reactivations were observed. The early response rate was 19% in patients with and 63% in patients without cirrhosis. Twenty-three (19.8%) subjects stopped therapy. Among 54 evaluable early responders, 21 had a sustained response. The rate of sustained response was comparable in group 1 (18.3%) and group 2 (18.2%). All sustained response subjects and some non-responders were HCV-RNA negative at the end of follow-up. Histological improvement was seen only after sustained response. Cirrhosis developed in 20% of non-responders. Overall, interferon induced a long-lasting remission of chronic hepatitis C in about one of every five patients.

In a population predominantly infected by hepatitis C virus type 1, 12 months of therapy with high doses of interferon does not confer any additional benefit on the early response or sustained response rates as compared to a 6-month course.

Liver stellate cell proliferation and differentiation into myofibroblast-like cells is related to the development of liver fibrosis. Several cytokines, including interferons, regulate liver stellate cell proliferation and phenotypic modulation. Recent studies indicate that human liver stellate cells express the alpha-isotype of actin, specific to smooth muscle cell differentiation. We aimed to evaluate the expression of alpha-smooth muscle actin-positive liver stellate cells in patients with chronic viral hepatitis and to evaluate whether and how such expression can be modified by alpha-interferon treatment.

Using immunohistochemistry, and a semi-quantitative scoring method, we evaluated alpha-smooth muscle actin expression in liver stellate cells before and after alpha-interferon therapy in a series of liver biopsies from 44 patients with chronic viral hepatitis.

Before therapy, a large number of liver stellate cells expressing alpha-smooth muscle actin were present throughout all acinar zones. A significant reduction in alpha-smooth muscle actin expression by liver stellate cells was demonstrated in biopsies performed after suspending the interferon treatment. The drop in the number of alpha-smooth muscle actin-labelled cells after therapy correlated closely with the improvement in the histological index of activity.

The results suggest a specific effect of interferon on liver stellate cells, possibly related to its anti-inflammatory action.

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.

To evaluate the usefulness of proliferating cell nuclear antigen (PCNA) immunostaining in the assessment of the efficacy of interferon (IFN) therapy in chronic hepatitis C, we investigated the proliferative activity of hepatocytes in 67 patients with chronic hepatitis C, using this immunostaining method. The percentage of PCNA-positive hepatocytes was 2.4% in patients with chronic persistent hepatitis, 2.5% in those with chronic aggressive hepatitis 2A, and 3.9% in those with chronic aggressive hepatitis 2B. The PCNA count increased with the progression of the liver disease. Patients were classified as complete, partial, and non-responders to IFN; the percentage of PCNA-positive hepatocytes before IFN therapy was 1.6% in the complete responders, 3.9% in the partial responders, and 4.9% in the non-responders. There was a significant negative correlation between the percentage of PCNA-positive hepatocytes and the response to IFN treatment. Thirty-two of 53 cases (60.4%) in which the PCNA labeling index (LI) was less than 5.0 were complete responders compared with 13 of 14 cases (92.9%) in which the PCNA LI was higher than 5.0, representing partial responders or non-responders (P < 0.001). Most complete responders had a low PCNA LI, irrespective of HCV genotype. Our findings indicate that PCNA immunostaining is a simple and reliable index of cell proliferation in liver regeneration, and may be a useful predictor of the response to IFN treatment in chronic hepatitis C.

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.

Response to a 1-yr course of interferon-alpha 2b was assessed in 18 patients with chronic hepatitis C virus infection in relation to clinical, biochemical and histological parameters and to the presence or absence of hepatitis C virus RNA and the presumed replicative form of the virus (negative-strand hepatitis C virus RNA) in serum, liver and peripheral blood mononuclear cells. The findings were compared with those in seven untreated patients studied over the same period. At the start of the study, positive-strand hepatitis C virus RNA was found in sera of all 25 patients, in livers of 24 and in peripheral-blood mononuclear cells of 19 of 22 tested; negative strand was found in livers of 11 and in peripheral-blood mononuclear cells of 15 of 22. Negative-strand hepatitis C virus RNA was not found in the serum of any patient at any stage. All of the five treated patients considered to show complete response during the study period cleared hepatic hepatitis C virus RNA, and four also became seronegative, but three had evidence suggestive of viral replication in their peripheral-blood mononuclear cells; two of these last patients subsequently relapsed. Loss of hepatic hepatitis C virus RNA was the only significant difference between these five and the seven partial and six nonresponders, but it is uncertain whether the observed changes were due specifically to interferon-induced modulation of virus expression because similar (apparently spontaneous) changes were seen in four of the untreated patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Hepatitis C virus is the most frequent cause of chronic non-A, non-B hepatitis, and the antibodies to structural and nonstructural proteins encoded by viral genome have been suggested to be markers of ongoing HCV infection. We studied the behavior of these antibodies during interferon therapy in 18 patients with chronic hepatitis C and also during a follow-up period of at least four years. A significant decrease of anti-HCV titer was found only in patients who had shown positive response to therapy and all of them were anti-HCV negative at the end of follow-up. Analysis by recombinant immunoblotting assay showed that only anti-c100 were affected by interferon therapy, whereas anti-c22 and anti-c33 were not modified. Using polymerase chain reaction to detect small amounts of HCV genome in serum, we could confirm that the behavior of HCV-RNA during and after interferon therapy is similar to that of anti-HCV and the loss of anti-c100 seems to be closely related to HCV-RNA disappearance from serum. Our patients with chronic hepatitis C were found to be of type 1b and 2, according to the recent score of Simmonds, and the clearance of serum HCV-RNA during treatment and its sustained negative status are closely related to genotype 2 and to long-term positive response to interferon.