Lymphoblastoid and recombinant alpha-A interferon therapy of chronic hepatitis B virus infection. The Royal Free Hospital experience

The natural course of chronic hepatitis B virus infection and its management

Chronic infection with the hepatitis B virus (HBV) runs a long natural course during which underlying changes in liver histology can progress to cirrhosis and hepatic decompensation, as well as to hepatocellular carcinoma. Therapeutic intervention is currently aiming at suppression of HBV replication by applying a number of pharmacological agents. For an optimum use of available therapies, good knowledge of the natural course of chronic infection, as well as of the role played by several viral, host, and environmental factors, is mandatory. The larger part of this chapter deals with how to treat the various subsets of patients with chronic hepatitis B (CHB), using mainly three first-line drugs: pegylated interferon-α2a, entecavir, and tenofovir, administered either in finite courses or indefinitely. The frequency of virological, serological, biochemical, and histological responses in the various subsets of patients, both during and after stopping treatment, is reviewed. It is stressed that the application of the highly potent antivirals entecavir and tenofovir, with acceptable safety records and with a high barrier to HBV resistance, represents major progress in the treatment of CHB. Despite the hitherto important developments in the treatment of viral hepatitis B, clinical cure of chronic HBV infection with HBsAg loss is achievable only in a few treated patients while eradication of HBV infection appears unrealistic. Development of new pharmacological agents acting at multiple targets of the replicative cycle of HBV may achieve higher efficacy and even cure of CHB.

Management of severe acute to fulminant hepatitis B: to treat or not to treat or when to treat?

Despite a decline in cases of acute hepatitis B and the low hepatitis B virus (HBV) chronicity rates in adults, still some patients progress to HBV-related fulminant liver failure. In this review, we discuss treatment options that may prevent the progression of severe acute hepatitis B to fulminant liver failure and death. In severe acute HBV with prolonged prothrombin time and increased bilirubin, interferon failed to be effective while antiviral treatment, particularly with lamivudine, appears to improve survival (mean survival almost 80%). Outcome without antiviral therapy has remained considerably poor, whereas there is no convincing evidence of amelioration of HBV-targeted immunity. Of note, most patients who died or required transplantation despite lamivudine therapy, were started on lamivudine at advanced stages compared with those survived. This suggests that prompt and timely antiviral therapy is crucial. Owing to the abovementioned results the design of randomized placebo-control trials in the setting of severe acute hepatitis B seems unethical. On the contrary, the design of multicentre double-blind randomized trials to compare the efficacy between lamivudine and entecavir or even tenofovir in acute severe HBV cases is ideally needed, but these studies appear to be very difficult to perform considering that these cases are not frequent and therefore, it is almost impossible to have two arms adequately numerous and homogenous for statistical evaluation. Thus, in the absence of solid evidence based data, the hepatologists could treat their patients with severe acute hepatitis B with lamivudine or the most potent antivirals entecavir or tenofovir.

Milestones and perspectives in viral hepatitis B

There have been numerous research milestones since the discovery of the hepatitis B virus (HBV) in the 1960s. These mark major advances in the serology and epidemiology of HBV infection, in identifying the wide clinical spectrum of acute and chronic hepatic diseases as well as the extrahepatic conditions induced by this virus, the molecular biology of the virus including its variants and mutants, its molecular diagnosis and monitoring, the host immune responses to the infecting virus, the pathogenesis and immunopathogenesis of liver disease as well as its natural course and outcome. These landmark discoveries are the firm background for current and future developments in treatment. There are three consecutive and partly overlapping chronological periods to treatment milestones beginning with recombinant standard interferon-alpha (IFN-α) in the 1980s, then oral antivirals from 1998 to the present and in 2005 pegylated IFN-α (PEG-IFN). The renewed interest in PEG-IFN-α treatment is now focused on both HBeAg-positive and HBeAg-negative chronic hepatitis B and it now also aims at HBsAg loss when associated with on-treatment monitoring of serum HBV DNA and HBsAg levels, resulting in the closest thing to a cure of hepatitis B. The impressive progress made in all aspects of hepatitis B research suggests that curative therapy may be developed for all patients and for all phases of HBV infection in the foreseeable future. However for the moment, realistic efforts should be made to make treatment as widely available and affordable as possible and to apply current therapies to significantly reduce HBV morbidity and mortality.

Influence of HIV infection on the response to interferon therapy and the long-term outcome of chronic hepatitis B

BACKGROUND & AIMS

The outcome of chronic hepatitis B and the efficacy of interferon alfa (IFN-alpha) remain controversial in human immunodeficiency virus (HIV)-positive patients. We analyzed the influence of HIV coinfection on the response to IFN-alpha therapy, long-term virologic status, progression to cirrhosis, and mortality.

METHODS

This was a retrospective follow-up cohort study of 141 consecutive hepatitis B e antigen-positive patients (69 HIV positive) followed up for 45 months.

RESULTS

The short-term response to IFN-alpha therapy was not significantly different in HIV-positive and HIV-negative patients (28% vs. 51%; P = 0.06) but was poorer in cases of low CD4 cell count (P = 0.038). The hepatitis B virus (HBV) reactivation rate was higher in HIV-positive patients (P = 0.033) and was associated with low CD4 cell count. The risk of cirrhosis was higher in HIV-positive patients with a CD4 cell count <200/mm(3) (relative risk [RR], 4.57; P = 0.007), in IFN-alpha-untreated patients (RR, 2.63; P = 0.041), in patients older than 33 years (RR, 4.59; P = 0.008), and in cases of high necroinflammatory score at baseline (RR, 1.27; P = 0.010). Cirrhosis-related death was more frequent in HIV-positive patients with low CD4 cell count at baseline (P = 0.041), in alcohol consumers (P = 0.001), in IFN-alpha-untreated patients (P = 0.052), and in patients with high histology activity index at baseline (P = 0.005).

CONCLUSIONS

HIV coinfection was associated with poorer response to IFN-alpha therapy, more frequent HBV reactivations, and increased incidence of cirrhosis and cirrhosis-related death in cases of low CD4 count. IFN-alpha therapy decreased the incidence of HBV cirrhosis regardless of HIV status or serologic response.

Treatment of chronic hepatitis B with interferon alpha-2b and interleukin-2

A total of 37 patients with histologically confirmed chronic viral hepatitis B and presence of HBV-DNA and HBsAg in the serum were treated in a randomized, prospectively controlled multicenter trial either with recombinant IFN alpha-2b alone or a combination of IFN alpha-2b and recombinant IL-2. Twenty-two patients from group A were treated with 3 MU of IFN alpha-2b s.c. thrice weekly for 5 months. Starting at month 2 IL-2 was added: priming doses of 1.5 million CU were given s.c. on the first 2 days of each of the remaining 3 months, followed by maintenance doses of 0.3 million CU daily for 5 days per week. Fifteen patients from group B received 5 MU of IFN alpha-2b s.c. thrice weekly for 5 months. Five patients from group A (24%) and 4 patients from group B (28%) cleared HBV-DNA and HBeAg from the serum, and normalized elevated serum aminotransferase activities. The response rate in both groups did not differ significantly. Since side effects were more pronounced during combination therapy than in IFN alpha-2b monotherapy, it is suggested that treatment with IFN alpha-2b alone is preferable to a regimen of IFN alpha-2b/IL-2 applied according to the above schedule.

To treat or not to treat? The judicious use of interferon-alpha-2a for the treatment of chronic hepatitis B

Based on results from extensive clinical research, interferon-alpha-2a (IFN-alpha-2a, Roferon-A, F. Hoffmann-LaRoche Ltd., Switzerland) and other interferons have been registered for the treatment of chronic active hepatitis B. The officially recommended dose regimen is 4.5 MIU (or 2.5 MIU/m2) thrice weekly for 6 months. To present guidelines for the optimization of treatment for individual patients, 3 major controlled trials from our worldwide research program with a total of 416 patients were reviewed in a meta-analysis. Before deciding whether to treat or not, the history, prognosis and chances of treatment success for a given patient must be carefully assessed. Liver histology and repeated quantitative measurements of markers for viral replication (HBV-DNA, HBeAg) and biochemical markers for liver disease such as ALT are valuable indicators. After the decision to treat, monthly quantitative measurements of these markers make it possible to monitor therapeutic success. Depending on the course they run, treatment can continue unchanged, be adjusted in dose or duration until a full response is achieved, or be terminated early in case of evidence of non-response.

Treatment of hepatitis B virus infection with interferon. Factors predicting response to interferon

Several randomised controlled trials have been undertaken to evaluate the efficacy of alpha-interferon in the therapy of chronic hepatitis B. In patients with HBe antigen-positive disease acquired in adult life the response rates vary from 25-50%. In those infected at birth, response rates are lower. Twenty-one pretreatment variables were assessed for their significance in response prediction using data from 114 patients given alpha-interferon for chronic hepatitis B virus infection. In those patients who had received a minimum of 90 million units per m2 total dose over 12 weeks, a negative anti-human immunodeficiency virus antibody status (p less than 0.001), chronic active hepatitis on liver biopsy (p less than 0.005), high AST level (p less than 0.001), low hepatitis B virus DNA level (p less than 0.001) and a history of acute hepatitis (p less than 0.005) were all associated with an increased likelihood of response on univariate analysis. On stepwise logistic regression analysis, hepatitis B virus DNA, AST and a history of acute hepatitis predicted response independently (p less than 0.05). The most reliable combination of predictive factors was a negative anti-human immunodeficiency virus antibody status, with either a positive history of acute icteric hepatitis and AST greater than 45 IU per liter or no history of acute icteric hepatitis and AST greater than 85 IU per liter, which predicted response in 77% with a specificity of 79% (p less than 0.001). The loss of HBsAg in addition to HBeAg and hepatitis B virus DNA was more likely to occur in patients with chronic infection of less than 2 years duration (p less than 0.001).

Treatment of chronic hepatitis B with interferon alfa-2b

A total of 58 patients with histologically confirmed chronic viral hepatitis B and presence of hepatitis B surface antigen and hepatitis B virus DNA (HBV DNA) in the serum were randomized in a prospectively controlled trial. Thirty patients were treated with 3 megaunits of recombinant interferon alfa-2b (INTRON A, R Schering-Plough, Essex Corporation) subcutaneously thrice weekly for 4 months. Twenty-eight controls received no treatment. The post-treatment follow-up period consisted of 6 months. Twenty-eight treated patients and 27 controls completed the protocol. One female patient of the treatment group showed a complete response, and eight other treated patients (32%) showed a partial response to therapy. Three patients in the control group (11%) lost hepatitis B e antigen and HBV DNA spontaneously. This finding is statistically significant (p less than 0.05). The elimination of hepatitis B virus markers from the serum was associated with a normalization of aminotransferase activities in the serum. Reactivation of hepatitis was not observed after seroconversion.

Which patients with chronic hepatitis B virus infection will respond to alpha-interferon therapy? A statistical analysis of predictive factors

Twenty-one pretreatment variables were assessed for their significance in response prediction using data from 114 patients given alpha-interferon for chronic hepatitis B virus infection. In those patients who had received a minimum of 90 million units per m2 total dose over 12 weeks, a negative anti-human immunodeficiency virus antibody status (p less than 0.001), chronic active hepatitis on liver biopsy (p less than 0.005), high AST level (p less than 0.001), low hepatitis B virus DNA level (p less than 0.001) and a history of acute hepatitis (p less than 0.005) were all associated with an increased likelihood of response on univariate analysis. On stepwise logistic regression analysis, hepatitis B virus DNA, AST and a history of acute hepatitis predicted response independently (p less than 0.05). The most reliable combination of predictive factors was a negative anti-human immunodeficiency virus antibody status, with either a positive history of acute icteric hepatitis and AST greater than 45 IU per liter or no history of acute icteric hepatitis and AST greater than 85 IU per liter, which predicted response in 77% with a specificity of 79% (p less than 0.001). The loss of HBsAg in addition to HBeAg and hepatitis B virus DNA was more likely to occur in patients with chronic infection of less than 2 years duration (p less than 0.001).

A controlled trial of human lymphoblastoid interferon in chronic hepatitis B in Italy

Sixty-four heterosexual Italian carriers of HBsAg with chronic HBeAg and hepatitis B virus DNA-positive hepatitis were assigned randomly either to receive human lymphoblastoid interferon (injections of 5 million units per m2 three times per week for 6 months) or to serve as untreated controls. After 18 months of follow-up evaluation, 26 of the 33 treated patients (79%) had cleared hepatitis B virus DNA, 23 (70%) had lost HBeAg and 20 (61%) had seroconverted to anti-HBe. Fifteen of the 31 controls (48%) had cleared hepatitis B virus DNA (p = 0.01), 12 (39%) had lost HBeAg and nine (29%) had seroconverted to anti-HBe (p = 0.002). Eight treated patients but only one control had lost HBsAg and seroconverted to anti-HBs (24% vs. 3%, p = 0.01). Treated patients cleared hepatitis B virus markers after a mean interval of 4 months, compared with 8 months in the controls. All responders to interferon cleared intrahepatic HBcAg, and 50% showed histological improvement. The baseline hepatitis B virus DNA levels and the original histology were not predictive of a response to therapy; women appeared to respond better than men. Lymphoblastoid interferon provides an effective therapy in the heterosexual Italian patient with chronic hepatitis B.

Histological improvement after anti-viral treatment for chronic hepatitis B virus infection

Sequential liver biopsies were taken from 66 patients with chronic hepatitis B virus (HBV) infection being followed in randomised controlled trials of therapy with alpha interferons or adenine arabinoside 5'-monophosphate. In the group of 23 patients responding to treatment with the permanent loss of HBe antigen and HBV-DNA from their serum, there was a significant reduction in hepatic inflammatory activity and none developed cirrhosis. In contrast, inflammatory activity continued in the group of 24 patients that did not respond to therapy, and in the group of 19 patients who received no therapy. Two untreated controls progressed to cirrhosis. Further studies confirmed that in those clearing HBeAg and HBV-DNA from the serum, HBcAg and HBeAg were also lost from the liver. This study demonstrates that, as in natural seroconversion, successful treatment of chronic HBV infection is associated with loss of hepatic as well as serum markers of HBV replication, and is followed by a reduction in hepatic inflammation. Antiviral therapy may prevent progression to cirrhosis in some cases.

Treatment of protracted acute type B hepatitis with recombinant alpha-A-interferon. A pilot study

Six individuals with protracted acute type B hepatitis were treated with recombinant alpha-A-interferon for 12 weeks. Two females eliminated the HBV completely, while 4 males did not respond. Response was preceded by a flare-up of the liver disease. It appears that responses to interferon are not higher in protracted acute type B hepatitis than in progressed chronic active hepatitis B. This assumption has to be proven in larger studies on a statistical basis.

Clearance of pre-S2 antigen: a marker of successful interferon therapy in hepatitis B virus infection

The relation between viral replication, the presence of HBsAg and pre-S2 in serum and eventual clinical outcome has been investigated in fourteen patients undergoing treatment with lymphoblastoid interferon for chronic hepatitis B virus (HBV) infection. In four patients permanent loss of pre-S2 was accompanied by loss of serum HBV-DNA in association with a marked elevation of serum aspartate aminotransferase activity and in each of these cases HBsAg was subsequently cleared from serum. In contrast there was no significant fluctuation in the concentration of either pre-S2 or HBsAg in four cases not responding to therapy although substantial or complete inhibition of viral replication had been observed during treatment. In the third group, permanent loss of HBV-DNA was observed but in these cases pre-S2 and HBsAg persisted in serum, albeit at lower concentrations, while in this group loss of HBV-DNA from serum was not accompanied by a flare in disease activity. These results suggest first, that assay of pre-S2 is a further measure of the response to interferon and second that in some cases interferon enhances immune recognition of both the pre-S2 and HBsAg polypeptides.