Randomized, controlled trial of recombinant human alpha-interferon in patients with chronic hepatitis B

A pilot study of 2',3'-dideoxyinosine for the treatment of chronic hepatitis B

The nucleoside analog 2',3'-dideoxyinosine, currently being used to treat patients infected with the human immunodeficiency virus, has been shown to inhibit viral replication in certain cell culture systems of hepatitis B virus and the duck model of chronic hepatitis B infection. We studied the effect of dideoxyinosine on viral replication in patients with chronic hepatitis B. In the initial dose-finding phase, patients received sequential 2-wk courses of dideoxyinosine in escalating doses of 3, 6 and 9 mg/kg/day. In the second, long-term treatment phase, patients received dideoxyinosine at a dose of 9 mg/kg/day for 12 wk. Dideoxyinosine was given orally in three divided doses. The effects of dideoxyinosine on hepatitis B were assessed by serial measurements of ALT, hepatitis B virus DNA and DNA polymerase activity in serum. Six patients completed the dose-finding phase, and five patients continued into the long-term treatment phase. No significant differences were seen in serum aminotransferases, hepatitis B virus DNA levels or DNA polymerase activity at any time during treatment when compared with pretreatment levels. All patients remained positive for HBeAg during treatment and during 6 mo of follow-up. Thus at the doses tested, dideoxyinosine had no appreciable effect on viral replication in patients with chronic hepatitis B.

Histological behaviour of chronic hepatitis in patients treated with alpha interferon

To evaluate the histological effects of alpha Interferon (IFN) therapy, serial liver biopsy specimens from 30 patients with chronic hepatitis were studied. The biopsies were examined using a scoring system. After 12 mths of IFN therapy responders were 8 out of 11 HBV infected patients, 10 out of 12 HCV infected patients and only 1 out of 7 patients with cryptogenetic hepatitis. As spontaneous improvement of hepatic changes is infrequent, our data indicate that in terms of histological patterns interferon therapy is effective in chronic viral hepatitis.

Effects of interferon-alpha therapy on serum and liver HBV DNA in patients with chronic hepatitis B

The aim of this study was to evaluate the effect of interferon-alpha therapy on serum and liver HBV DNA in 20 patients with chronic hepatitis B and to correlate the presence or absence of HBV DNA with the clinical response. There were 11 responders and all lost HBV DNA from the serum. Ten of the 11 were followed for 36 months following IFN treatment and remained well with absence of HBeAg and HBV DNA from the serum and with normal ALT. Five also lost HBsAg. HBV DNA became undetectable in the liver of nine of 10 of these patients in whom liver tissue was available for study. HBV DNA persisted in the liver of seven of nine nonresponders and was not detected in two in spite of the presence of HBV DNA and HBeAg in the serum of these two patients. We conclude that IFN may induce long remissions in patients with chronic hepatitis B with loss of HBV DNA from the serum and that occasionally HBV DNA may persist in the liver of such patients.

Chronic hepatitis B and C. What is the status of drug therapy?

Chronic hepatitis remains difficult to treat. Use of interferon has been successful against both hepatitis B and C viruses, but the outcome of long-term administration has yet to be determined. Not all patients respond to interferon, however, and some have side effects that cause them to discontinue therapy. Dr Wright discusses the results of studies to evaluate therapy with alpha, beta, and gamma interferon as well as with other agents, such as ribavirin, thymosin, and ursodeoxycholic acid.

Interferon treatment for hepatitis B-associated membranous glomerulonephritis in two Chinese children

Two Chinese boys, aged 3.5 and 5 years, developed nephrotic syndrome and were chronic carriers of hepatitis B virus surface antigen (HBsAg) and hepatitis B virus e antigen (HBeAg). Renal biopsy showed membranous glomerulonephritis and liver biopsy showed chronic persistent hepatitis. They were given interferon-alpha-2a at a dose of 5 MU/m2 on alternate days for 12 and 16 weeks after 2 years of persistent nephrotic syndrome. Patient 1 showed complete remission and resolution of hepatosplenomegaly, but his serum remained positive for HBsAg, HBeAg and hepatitis B virus DNA. Patient 2 showed only a transient clinical response and seroconversion from HBeAg to anti-HBe status. Although not always successful, interferon treatment should be considered in severe persistent nephrotic states, since there is at present no satisfactory treatment for this form of glomerulonephropathy.

Effects of alpha-interferon on gamma-interferon production of peripheral blood mononuclear cells in hepatitis B virus carriers

We studied gamma-interferon production of phytohemagglutinin-stimulated peripheral blood mononuclear cells in response to alpha-interferon in hepatitis B virus carriers and healthy individuals. The magnitude of gamma-interferon production was significantly higher in patients with anti-HBe antibody than in patients with HBe antigen and healthy individuals. Furthermore, alpha-interferon augmented the production of gamma-interferon of peripheral blood mononuclear cells from patients with active liver injury [serum alanine aminotransferase (ALT), greater than 40 U/L], but not that from patients with inactive liver injury (serum ALT, less than 40 U/L) or healthy individuals. These results suggested that alpha-interferon could enhance the cellular immune response against hepatitis B virus by augmenting the endogenous production of gamma-interferon in patients with active liver injury, implying that the responsiveness to alpha-interferon might be responsible for liver cell injury.

Quantitation of hepatitis C virus RNA by competitive polymerase chain reaction

Since the amount of hepatitis C virus (HCV) RNA might be correlated with the degree of severity of hepatitis and response to treatment, quantitation of HCV RNA in serum was established using competitive polymerase chain reaction (PCR). Known amounts of a plasmid containing HCV-cDNA were co-amplified with a standard dilution series of a competitive template which shared the primers' sequences but differed from the wild type cDNA in having a deletion. Accurate quantitation was obtained by comparing the amount of both products. Quantitation of serum HCV RNA was carried out in two patients' serum samples which were also used to infect chimpanzees. The concentration of HCV RNA in these two sera was calculated to be 1 pg/ml (non-infectious at 10(-3) dilution) and 1-10 pg/ml (infectious at 10(-5) dilution). The procedure was subsequently used to analyze serial changes in serum HCV RNA in three patients who were treated with alpha-interferon. During treatment, the levels of alanine aminotransferase showed a significant decrease in all patients and the amount of HCV RNA fell from 1 fg/ml, 1 pg/ml, and greater than 10 pg/ml to 0.1 fg/ml, 100 fg/ml, and 1 pg/ml, respectively. The decrease in the amount of HCV RNA after treatment was related to the initial amount of serum HCV RNA. These results suggest that quantitation of HCV RNA may be useful not only for understanding the course of HCV infection but also for evaluating treatment for HCV infection.

Antiviral effect of prolonged intermittent lymphoblastoid alpha interferon treatment in chronic hepatitis B

In a European multicentre study 40 patients with HBeAg positive chronic hepatitis B virus (HBV) infection were treated with 5 mega units of lymphoblastoid alpha-interferon daily according to the following regimen: a four week primer course, four weeks of rest and a second course lasting 16 to 30 weeks. After 52 weeks of follow up, a response (HBeAg seroconversion and HBV-DNA negativity) was observed in 22 patients (55%). HBsAg seroconversion occurred in five patients (12.5%). One patient exhibited a relapse for serum HBeAg and HBV-DNA after cessation of treatment. According to a response prediction model, the observed response rate was not related to the selection of patients likely to respond. The initial interferon course induced a reduction of the serum HBV-DNA and HBeAg levels of 87% and 18%, respectively, leading to a significantly lower level of viral replication activity at the start of the second longterm course compared with baseline. After 24 weeks of follow up (week 16 of the second course), 19 (48%) patients exhibited a response, 13 (32%) a partial response (HBeAg < 50% of initial level or HBV-DNA negative) and 8 (20%) no response. For eight of the 13 partial responders treatment was stopped at week 24 and viral replication rebounded to pretreatment values. In the last five partial responders prolongation of therapy up to week 38 led to a definite response and HBsAg seroconversion in three of the five patients. The results of this study suggest that a short primer course and prolongation of therapy may help to enhance the response rate of alpha-interferon therapy for chronic hepatitis type B.

Changes in ultrastructure of hepatocytes and liver test results before, during, and after treatment with interferon-beta in patients with HB(e)Ag-positive chronic active hepatitis

We studied the histological and ultrastructural changes in the liver and alterations in the liver test results before, during, and after treatment with human interferon-beta from five patients with hepatitis B e antigen-positive chronic active hepatitis. A daily dose of 3 x 10(6) to 6 x 10(6) units of interferon-beta was given intravenously for four weeks. The total index of periportal and portal inflammation, intralobular degeneration, and focal necrosis before treatment was decreased significantly six months after treatment (P less than 0.05). Ultrastructurally, the structure of endoplasmic reticulum was irregularly shaped or fragmentally decreased during treatment, but these disappeared six or 12 months after treatment. Glycogen particles diminished greatly during treatment. The alanine aminotransferase concentrations in these patients increased during treatment. Serum albumin and cholinesterase levels decreased significantly at the fourth week of treatment (P less than 0.01) and at the third day (P less than 0.01) to the second week (P less than 0.05) of treatment, respectively. These results suggest that interferon-beta injures endoplasmic reticulum and glycogen areas and damages the cholinesterase activity in the early stage of treatment and protein synthesis in patients with hepatitis B e antigen-positive chronic active hepatitis.

Serum pre-S1 and pre-S2 antigens as prognostic markers in interferon therapy for chronic hepatitis B

We investigated the changes of serum pre-S1 and pre-S2 antigens before and after interferon therapy in 35 carriers with HBeAg, to examine their clinical significance in the therapy. Both antigens were measured quantitatively by solid-phase enzyme immunoassays using monoclonal antibodies specific to each antigen. The titers of these antigens of responders before therapy were significantly lower (p less than 0.001) than those of non-responders (6.23 +/- 1.09 versus 8.65 +/- 2.09 and 4.46 +/- 1.27 versus 6.50 +/- 1.50, respectively). The titers decreased significantly 6 months after interferon therapy in the responders (p less than 0.05), whereas they did not change in the non-responders. Our findings indicate that pre-S1 and pre-S2 antigens have a close correlation with hepatitis B virus replication and are valuable markers for predicting the responsiveness to interferon therapy.

Measurements of iron status in patients with chronic hepatitis

Eighty patients with chronic viral hepatitis were screened for evidence of iron overload. Elevated serum iron values were noted in 36% of cases; serum ferritin values were above normal in 30% of men and 8% of women. Twenty-eight additional patients with chronic hepatitis for whom liver tissue was available for determination of iron content were evaluated to study the significance of iron overload in association with chronic hepatitis. Although 46% had elevated serum iron, ferritin, or transferrin-saturation levels, the hepatic iron concentration was elevated in only four cases, and the hepatic iron index was in the range for hereditary hemochromatosis (greater than 2.0) in only two of these. Serum aspartate aminotransferase activities correlated with serum ferritin levels in these patients, suggesting that ferritin and iron levels were increased in serum because of their release from hepatocellular stores associated with necrosis. Thus, in patients with chronic hepatitis in whom hereditary hemochromatosis is suspected, a liver biopsy should be performed with quantitation of hepatic iron and calculation of the hepatic iron index to confirm the diagnosis.

A controlled trial of interferon with or without prednisone priming for chronic hepatitis B

In a randomized, controlled trial of recombinant interferon alfa-2b with or without prednisone priming in Chinese adults with chronic hepatitis B virus infection, stratified randomization for pretreatment serum alanine aminotransferase levels was done. Partial or complete antiviral responses were achieved in 17 (21.5%) of 79 treated patients and 3 (8.3%) of 36 controls (P = 0.14). The response to interferon treatment was significantly better in those who had elevated pretreatment transaminase levels and comparable to that reported in white patients [15 (38.5%) of 39 patients compared with 2 (5%) of 40 who had normal pretreatment transaminase levels (P = 0.0005)]. The spontaneous seroconversion rate was also higher among the controls with elevated transaminase levels [3 (18.8%) of 16 compared with 0 of 20 with normal transaminase levels], but this difference was not statistically significant (P = 0.16). Among the interferon-treated patients, prednisone priming appeared to have a marginal benefit over treatment with interferon alone in patients with elevated transaminase levels (43% vs. 33%), but not in those with normal transaminase levels (0% vs. 9.5%). It was confirmed that Chinese patients with normal transaminase levels respond very poorly to interferon alfa therapy. However, the response was significantly better in patients with elevated transaminase levels.

Development of thyroid disease during therapy of chronic viral hepatitis with interferon alfa

Six of 237 (2.5%) patients with chronic viral hepatitis who were treated with recombinant interferon alfa developed thyroid disease while on treatment. Three patients developed hyperthyroidism, two of whom developed detectable levels of thyroid-stimulating immunoglobulin; three patients developed hypothyroidism in association with high titers of antithyroglobulin and/or antimicrosomal antibodies. The thyroid disease did not remit when interferon therapy was stopped, and all six patients required definitive therapy for the thyroid disease. These findings suggest that a small proportion of patients treated with interferon alfa develop autoimmune reactions and can develop autoimmune thyroid disease.

Chronic liver disease. The scope of causes and treatments

Evaluation of chronic liver disease begins with a carefully taken history, thorough physical examination, and standard laboratory tests. Often, however, other studies are required, such as a viral hepatitis panel, serologic tests for autoimmune markers, tests for antimitochondrial antibodies, measurement of serum iron and ceruloplasmin levels, liver biopsy, and imaging studies of the extra-hepatic bile ducts. Medical treatment of chronic active hepatitis, primary biliary cirrhosis, and primary sclerosing cholangitis remains unsatisfactory. Early treatment of hemochromatosis and Wilson's disease can prevent cirrhosis and liver failure. Liver transplantation is now a viable procedure for patients with end-stage chronic liver disease.

Protein composition of the hepatitis B virus e antigen in the natural course of disease and following interferon therapy

The protein composition of hepatitis B virus (HBV) e antigen (HBeAg) in serum was analyzed for 63 viremic patients with chronic HBV and found to consist of polypeptides with molecular masses of 16, 18, and 20 kDa (P16e, P18e, and P20e, respectively). Several experiments demonstrated their viral nature and HBeAg specificity and that P16e occurs either in free soluble form or as aggregates or immunocomplexes, while P18e and P20e occur essentially as immunocomplexes. Of 63 patients, 45 (71%) had P16e, P18e, and P20e, and the remaining 18 (29%) had only P16e. During the natural history of the disease, spontaneous clearance of HBV DNA and HBeAg took place only in six of nine (67%) patients with the three HBe polypeptides but in none of the five patients having P16e alone (P less than 0.05). Similarly, 22 of 23 (96%) patients responding to interferon therapy had P16e, P18e, and P20e, but these polypeptides occurred in only 14 of 26 (54%) nonresponder patients (P less than 0.001). Following the loss of HBV DNA and HBeAg, before the development of anti-HBe, the only HBe species detected were P18e and P20e, but these became no longer detectable after complete normalization of liver function tests. Therefore, persistence of P16e represents a failure to recover from HBV, and the appearance of HBe polypeptides P18e and P20e is associated with virus clearance and a favorable outcome of the disease.

Long-term follow-up of hepatitis B chronic carriers who responded to interferon therapy

We studied the long-term outcome of patients with chronic hepatitis B virus (HBV) infection who responded to interferon (IFN) therapy. Between 1983 and 1988, 120 patients were included in 5 different protocols; 94 patients were treated with IFN and 26 were controls. Loss of serum HBV-DNA was considered a partial response and occurred in 34 of the treated patients and in 10 of the controls. Only the partial-response patients were followed up for 14-64 months (mean 46 months). HBeAg disappeared in 32/34 of the partial-response treated patients and in 9/10 of the controls. During the follow-up period, 6/34 (18%) treated patients and 1/10 controls suffered a reactivation of the disease with reappearance of HBV-DNA. Only 8/34 (23%) treated patients and 1/10 of the controls lost HBsAg; no statistical differences were observed in baseline characteristics between HBsAg-negative patients and patients who remained HBsAg-positive. Of eight HBsAg-negative treated patients, four were serum HBV-DNA-negative upon polymerase chain reaction and thus formed the HBsAg-negative control cases. Although the frequency of HBsAg loss in treated patients is relatively low, the improvement in liver disease obtained from IFN therapy is sustained over a long period.

Relation of changes in hepatitis B virus replication markers to the outcome of interferon treatment in patients with chronic hepatitis

The relationship between the behavior of hepatitis B virus (HBV) replication markers and the response to treatment with recombinant alpha-2b interferon (IFN) was investigated in 11 patients with chronic hepatitis. At the end of 6 months of treatment, 4 patients showed a complete response to IFN: 2 more patients had seroconversion to HBeAb after 8 and 9 months of follow-up, respectively. The response to IFN was partial in the remaining patients. Pre-treatment levels of HBV DNA in patients showing complete response were lower than pre-treatment levels in patients with partial response: in addition, serum HBV DNA clearance during the treatment was associated with sustained remission more frequently than changes in the HBeAg/HBeAb system.

Antiviral therapy: current concepts and practices

Drugs capable of inhibiting viruses in vitro were described in the 1950s, but real progress was not made until the 1970s, when agents capable of inhibiting virus-specific enzymes were first identified. The last decade has seen rapid progress in both our understanding of antiviral therapy and the number of antiviral agents on the market. Amantadine and ribavirin are available for treatment of viral respiratory infections. Vidarabine, acyclovir, ganciclovir, and foscarnet are used for systemic treatment of herpesvirus infections, while ophthalmic preparations of idoxuridine, trifluorothymidine, and vidarabine are available for herpes keratitis. For treatment of human immunodeficiency virus infections, zidovudine and didanosine are used. Immunomodulators, such as interferons and colony-stimulating factors, and immunoglobulins are being used increasingly for viral illnesses. While resistance to antiviral drugs has been seen, especially among AIDS patients, it has not become widespread and is being intensely studied. Increasingly, combinations of agents are being used: to achieve synergistic inhibition of viruses, to delay or prevent resistance, and to decrease dosages of toxic drugs. New approaches, such as liposomes carrying antiviral drugs and computer-aided drug design, are exciting and promising prospects for the future.

Interferon-gamma receptor expression in chronic hepatitis B virus infection

It is known that interferon-gamma (IFN gamma) is not effective in inducing a sustained inhibition of HBV replication in patients with chronic HBV infection in contrast to interferon-alpha (IFN alpha). To determine whether this was related to IFN gamma receptor (IFN gamma-R) underexpression, binding characteristics of IFN gamma to peripheral blood lymphocytes were studied in chronic HBV infection using radioiodinated recombinant IFN gamma. Peripheral blood lymphocytes from patients with chronic HBV infection (n = 20), normal healthy controls (n = 12) and patients with non-viral related chronic liver disease expressed a similar number of IFN gamma-R (medians (ranges): 1891 (1581-2515); 1916 (1589-2441); 1893 (1692-2104) sites/cell, respectively, p = N.S.) with a similar dissociation constant (Kd approximately 0.7-2.7 nM). There was no correlation between IFN gamma-R expression and serum transaminase, serum HBsAg and HBV-DNA titres and liver histology. IFN alpha therapy in vivo also did not enhance IFN gamma-R expression (n = 3). There is therefore, no evidence from this data that IFN gamma-R is underexpressed in patients with chronic HBV infection to account for the difference in clinical response to these two forms of therapy.

Interferon alpha therapy in patients with chronic type C hepatitis: changes of serum ALT, anti-HCV & HCV-RNA

BACKGROUND

After the discovery of type C hepatitis virus, the studies on this virus are extensively progressing. The treatment of this viral infection is also widely progressing. Among many agents, recombinant interferon alpha therapy is generally accepted as an effective single agent. To evaluate the efficacy of interferon and to observe the changes of serum aminotransferase (ALT), antibody to hepatitis C virus (anti-HCV) and HCV ribonucleic acid (HCV-RNA), we treated 10 patients with chronic type C hepatitis for 6 months.

METHODS

Patients were randomly divided into 2 groups: 5 patients in group A received interferon and the other 5 in group B received no therapy. Interferon was administered at a dose of 3 million units (MU) daily for the first month and thrice weekly for the following 5 months, and followed up for 2 years.

RESULTS

In group A, serum ALT returned to normal in 4: 3, starting at the first month and one at the 3rd month of therapy and maintained normal throughout the follow-up period. In contrast, serum ALT level persistently fluctuated in 4 patients in group B. In one patient, serum ALT returned to normal one and a half years later. Regardless of therapy, serum anti-HCV titer remained unchanged in all patients. However, HCV-RNA, using polymerized chain reaction (PCR), became undetectable in all responded patients and in one untreated patient whose serum ALT returned to normal spontaneously.

CONCLUSION

This study suggested that interferon alpha therapy in patients with chronic type C hepatitis may be clinically effective. Our study also indicated that the detection of HCV-RNA by PCR is useful to predict the prognosis of chronic type C hepatitis.

Hepatitis B virus. New and evolving issues

Recent developments in molecular biology have advanced our understanding of the pathogenesis of HBV-induced disease. New data derived from the molecular analysis of clinical material have begun to bridge the gap between bench research and the clinical arena. In this review, we consider topics that have relevance to clinical management and that have not been summarized in the recent literature. The recent advances that have been made in the areas of HBV variants, in vitro cell culture systems, and extrahepatic infection are discussed in greater detail.

Therapies for hepatitis B virus: current status and future possibilities

Alpha-interferon is the first agent with proven therapeutic efficacy in humans with chronic HBV infection. Obviously, further research is needed to clarify and expand the role of interferon in this setting. In addition, an overall response rate of less than 50% illustrates the need for continuing innovation in the treatment of HBV infection especially in patients with predictors of poor outcome. Despite the advent of effective vaccines against HBV, this pathogen is likely to remain a source of serious human morbidity and mortality for the foreseeable future. Continuing efforts must be directed towards finding more effective therapies against HBV. A recent preliminary report suggests that thymosin. like interferon on immune modulator, may also be efficacious in the treatment of chronic HBV and deserves further study.

Effect of interferon-gamma on hepatitis B viral antigen expression in primary hepatocyte culture

Interferon-alpha has been shown recently to selectively enhance hepatocyte expression of HBsAg/pre-S2 in chronic hepatitis B virus infection in a way that may enhance immune recognition. To determine the effect of interferon-gamma on hepatitis B virus antigen expression, hepatocytes isolated from patients with chronic hepatitis B virus infection were incubated in the absence or presence of interferon-gamma and viral antigen expression was assessed by both radioimmunoassay and immunocytochemistry using appropriate monoclonal antibodies. Interferon-gamma inhibited the expression of all hepatitis B virus antigens tested. Intracellular HBsAg measured by radioimmunoassay of sonicated hepatocytes fell by 29% with 1 U/ml (p less than 0.01) and 36% with 10 U/ml of interferon-gamma (p less than 0.001) compared with control treatment. Secreted HBsAg was reduced by 19% with 10 U/ml of interferon-gamma (p less than 0.01). Intracellular HBeAg was also decreased by 29% with 1 U/ml (p less than 0.05) and 42% with 10 U/ml of interferon-gamma (p less than 0.05), but no significant change was found in the amount of secreted HBeAg. The proportion of hepatocytes containing various hepatitis B virus antigens and the intracellular viral antigen staining densities also fell significantly with interferon-gamma incubation. Interestingly, the addition of interferon-gamma abolished the augmenting effect of interferon-alpha on intracellular HBsAg. These data indicate that interferon-gamma, in contrast to interferon-alpha, has an inhibitory effect on hepatocyte expression of all hepatitis B virus antigens including HBsAg/pre-S2, suggesting that this may be one factor that accounts for their difference in clinical activity in patients with chronic hepatitis B virus infection.

Follow-up of recurrent hepatitis B and delta infection in liver allograft recipients after treatment with recombinant interferon-alpha

Reinfection of the graft with hepatitis B virus (HBV) and hepatitis delta virus (HDV) is a potential complication in patients undergoing orthotopic liver transplantation (OLT). Therefore, we added recombinant interferon-alpha (rIFNa) to the standard immunosuppressive regimen in 11 patients who received transplants following liver failure attributed to cirrhosis B (n = 10, with HDV co-infection in four cases) or fulminant hepatitis B (n = 1). Patients were treated with rIFNa for periods ranging from 2 to 3 months between the first and the 13th month after OLT. All patients received immunosuppressive treatment with low-dose corticosteroids, azathioprine and cyclosporine. Anti-HBs hyperimmune globulin was also administered. None of the patients showed evidence of severe allograft rejection. Seven patients suffered HBV reinfection of the graft with histological signs of acute hepatitis in five cases and transition to chronic hepatitis in one patient. Treatment with rIFNa did not prevent or reduce HBV replication. Reinfection of the graft with HDV was demonstrated by PCR in four patients co-infected with HDV. During treatment with rIFNa liver biopsy specimens from three reinfected patients were transiently negative for HDV antigen but not for HDV RNA, and the sera from two patients were transiently negative for HDV RNA. The data indicate that rIFNa can reduce HDV replication in reinfected liver allografts.

Effects of purine nucleoside analogues with a cyclobutane ring and erythromycin A oxime derivatives on duck hepatitis B virus replication in vivo and in cell culture and HIV-1 in cell culture

The effects on duck hepatitis B virus (DHBV) replication of specific analogues of two classes of chemical compounds not previously tested against hepadnaviruses are described. One is erythromycin A-9-methyloxime (EMO) and other oxime derivatives of erythromycin A, and the other is purine nucleoside analogues (cyclobut A and cyclobut G) with cyclobutane rings. Viral replication was assessed by measuring serum levels of DHBV DNA in infected ducklings and DHBV DNA in infected primary duck hepatocyte cultures. Administration of EMO 15 mg/kg of body weight IM to infected ducklings resulted in a rapid fall in DHBV DNA levels during therapy and a return to pretreatment levels after EMO administration was stopped. There was local toxicity at injection sites with muscle necrosis in some animals. When 100 mg/kg EMO was administered by gastric tube no such viral response was observed. The difference in virus response to EMO 15mg/kg IM and 100 mg/kg by gastric tube was not due to failure to achieve comparable blood and tissue levels of EMO administered by the different routes. The results suggest an indirect effect dependent on IM injection of EMO rather than a direct antiviral effect of the compound. Administration of cyclobut G or cyclobut A at 70 mg/kg IM led to a rapid reduction of DHBV DNA to undetectable levels in serum, and in only 1 of 4 animals did DHBV DNA became detectable again within 10 days after stopping the drug.(ABSTRACT TRUNCATED AT 250 WORDS)

Liver transplantation in HBs antigen (HBsAg) carriers. Prevention of hepatitis B virus (HBV) recurrence by passive immunization

Liver transplantation in HBs-antigen (HBsAg) positive allograft recipients is associated with a high risk of HBV recurrence some time after surgery. So far, results of measures to prevent recurrent HBV-infection by means of treatment with interferon, hepatitis B vaccination and short-term passive immunization with hepatitis B immunoglobulin (HBIg) or monoclonal antibody to HBsAg (anti-HBs) have been disappointing. In the present study the results of long-term, anti-HBs monitored passive immunization with HBIg is reported. In 23 HBsAg-positive liver transplant recipients an anti-HBs level of greater than or equal to 100 IU/l was maintained for 6 or 12 months, respectively. The rate of recurrent infection was found to be less than 20% under HBIg substitution, whereas 11 graft recipients with no or only short-term HBIg prophylaxis were reinfected by month 15 after transplantation. HBV recurrence was associated with chronic liver disease and recurrent cirrhosis in the allograft.

Orthotopic liver transplantation for patients with hepatitis B virus-related liver disease

Fifty-nine patients with prior hepatitis B virus infection underwent orthotopic liver transplantation. During the first 2 mo, mortality was not significantly different in the hepatitis B virus-infected group (25.5%) vs. a hepatitis B virus-immune control group (21%). Beyond 2 mo, the mortality, rate of graft loss, need for retransplantation and incidence of abnormal liver function were significantly higher in the hepatitis B virus-infected group. Treatment of the hepatitis B virus infection was attempted with passive immunization, combined active and passive immunization, alpha-interferon or nothing. The clinical outcome was not significantly influenced by any of these therapies. However, of the patients who lived more than 60 days, 6 of 22 treated with active plus passive immunization were cleared of HBsAg, something achieved once in 16 patients treated with alpha-interferon, never in 3 patients with passive immunization only and once in 4 patients with no therapy. In patients with recurrent hepatitis B virus infection, the pace of hepatitis development in the graft appeared to be accelerated, and this was particularly striking in patients who underwent multiple retransplantations at progressively shorter intervals. None of the patients who became HBsAg-negative had HBeAg preoperatively.

Orthotopic liver transplantation for patients with hepatitis B virus-related liver disease

Fifty-nine patients with prior hepatitis B virus infection underwent orthotopic liver transplantation. During the first 2 mo, mortality was not significantly different in the hepatitis B virus-infected group (25.5%) vs. a hepatitis B virus-immune control group (21%). Beyond 2 mo, the mortality, rate of graft loss, need for retransplantation and incidence of abnormal liver function were significantly higher in the hepatitis B virus-infected group. Treatment of the hepatitis B virus infection was attempted with passive immunization, combined active and passive immunization, alpha-interferon or nothing. The clinical outcome was not significantly influenced by any of these therapies. However, of the patients who lived more than 60 days, 6 of 22 treated with active plus passive immunization were cleared of HBsAg, something achieved once in 16 patients treated with alpha-interferon, never in 3 patients with passive immunization only and once in 4 patients with no therapy. In patients with recurrent hepatitis B virus infection, the pace of hepatitis development in the graft appeared to be accelerated, and this was particularly striking in patients who underwent multiple retransplantations at progressively shorter intervals. None of the patients who became HBsAg-negative had HBeAg preoperatively.

Short-term prednisolone followed by recombinant human alpha-interferon alone or combined with adenine-arabinoside in chronic hepatitis B. A prospective and randomized trial

Twenty-nine patients with chronic hepatitis B, presenting both hepatitis B surface antigen and hepatitis B virus deoxyribonucleic acid in serum, were studied in a randomized trial treatment consisting of oral prednisolone for 28 days followed 14 days after steroid withdrawal, by either a 55 s.c. injection course of 5 M unit recombinant human alpha-interferon (group 1, 14 patients) or by adenine-arabinoside (for 21 days) combined from the fourteenth day on with the same 55 s.c. injection schedule of interferon (IFN) (group 2, 15 cases). The two groups were well matched with respect to demographic, biochemical, virological and histologic features. Significant side-effects leading to premature discontinuation of interferon were observed in only four cases in group 2 and were always reversible. Efficacy was judged on a mean follow-up period of 17 months. For the whole population, 17 patients (59%) exhibited a sustained serum hepatitis B virus deoxyribonucleic acid disappearance which corresponded to a marked improvement in liver function as demonstrated by a quasi-normalization of their serum transaminase values (ALT with n less than 22 UI/l: 23 +/- 24 vs. 139 +/- 115 before treatment; P less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Interferon alfa therapy in patients with chronic hepatitis B virus infection. Effects on hepatitis B virus DNA in the liver

Pretrial and posttrial liver biopsy samples from 124 adult patients who participated in two randomized, controlled trials of interferon alfa therapy for chronic hepatitis B virus (HBV) infection were analyzed to determine the effects of interferon on the replication of HBV in the liver. Replicative forms of HBV DNA were detected in the pretrial biopsy samples from all and posttrial biopsy samples from 74% treated patients and 86% controls. Replicative forms of HBV DNA were detected in the posttrial biopsy samples from all patients who remained positive for hepatitis B e antigen and HBV DNA in the serum, in 77% treated patients and 80% controls who cleared HBV DNA in the serum but who remained positive for hepatitis B e antigen, but in only 19% treated patients and 40% controls who cleared HBV DNA as well as hepatitis B e antigen in the serum. Serum alanine aminotransferase levels were significantly lower in patients whose posttrial biopsies did not contain replicative forms of HBV DNA. In summary, we demonstrated that in most patients with chronic HBV infection treated with interferon alfa, serological response was associated with the disappearance of replicative forms of HBV DNA in the liver.

High doses of recombinant alpha-interferon or gamma-interferon for chronic hepatitis C: a randomized, controlled trial

Chronic hepatitis C is often a progressive liver disease for which there is no satisfactory treatment. We studied the efficacy of recombinant alpha-interferon or gamma-interferon in the treatment of this disease in comparison with a control group. Thirty patients were randomly assigned to three groups. Ten patients received 7.5 MU alpha-interferon/m2 body surface three times weekly for 3 mo, then 5 MU/m2 for 3 mo and 2.5 MU/m2 for 6 mo. Ten patients were treated with gamma-interferon at a dose of 2 MU/m2 for 6 mo and the other 10 served as controls without treatment. The mean serum ALT levels and liver histological findings improved significantly only in the patients treated with alpha-interferon. No changes were observed in patients treated with gamma-interferon or in controls. Five of 10 patients treated with alpha-interferon had complete responses (mean ALT normal during therapy). After treatment ALT returned to pretreatment levels in two of 5 patients. The long-term response rate after alpha-interferon therapy was 30% at 18 mo. We conclude that alpha-interferon is effective in controlling disease activity in a portion of patients with chronic hepatitis C. High doses of alpha-interferon do not appear to add further benefit in the response rate or relapse rate. gamma-Interferon therapy is ineffective.

Persistent hepatitis B virus following interferon alfa therapy and liver transplantation

A 44-year-old man with chronic hepatitis B virus infection and cirrhosis was treated with recombinant human interferon alfa for 67 days immediately before orthotopic liver transplantation and immunoprophylaxis with hyperimmune globulin to hepatitis B virus in the peritransplant period. Dot blots for hepatitis B virus DNA demonstrated marked reduction in viremia after 41 days of interferon alfa treatment. Southern analysis for hepatitis B virus in liver showed a pronounced decrement in actively replicating forms in the explant, although hepatic infection was still detectable. After liver transplantation, tests for serum hepatitis B virus DNA and hepatitis B surface antigen remained negative. The patient died 32 days after transplantation of causes unrelated to hepatitis B virus. DNA isolated from liver and other visceral organs at autopsy showed infection of the engrafted liver and the persistence of monomeric relaxed circular forms of hepatitis B virus DNA in pancreas, kidney, and spleen. Thus, graft reinfection occurred despite aggressive antiviral therapy and immunoprophylaxis combined with liver transplantation. Existing viral serological markers appear insufficiently sensitive to assess residual infectivity.

The use of interferon-alpha in virus infections

The interferons (IFN) act too slowly to arrest acute viral infections, but interferon-alpha (IFN alpha) preparations have proved useful in some chronic infections and will clearly be used increasingly in these in the future. In the preparations derived from human leucocytes or cultured B lymphoblastoid cells, which are in routine clinical use, mixtures of a number of distinct subtypes of human IFN alpha have been identified. There are also 3 slightly different versions of the same single subtype, IFN alpha-2, made by recombinant DNA procedures in bacteria. IFN alpha preparations are injected intramuscularly or subcutaneously. Dose-related side effects are common but usually tolerable, but prolonged treatment may cause increasing fatigue and depression. Some patients form neutralising antibodies which block the effects of the IFN; these appear to be relatively more common after recombinant IFN alpha-2 than after IFN derived from human cells. Given intranasally, IFN alpha can prevent a subsequent experimental rhinovirus infection, or the spread of natural colds within a family. Repeated administration progressively damages the nasal mucosa, so that long term prophylaxis is not possible. IFN alpha has proved useful in patients with papillomavirus warts of the larynx, ano-genital region (condyloma acuminata) and skin (common warts). Treatment regimens remain to be optimised and are likely to include surgery or other treatments. IFN alpha and zidovudine (azidothymidine) synergistically inhibit the growth of HIV in vitro, and combination are on trial in patients with early AIDS. Very large doses of IFN alpha are effective against Kaposi's sarcoma in some AIDS patients. In chronic hepatitis B, continuing virus replication may lead to cirrhosis or primary liver cancer. Earlier clinical trials with IFN alpha gave inconclusive results, but recent large studies have confirmed that 25 to 40% of patients obtain benefit; this probably results from both the antiviral and the immunomodulatory effects of IFN alpha. In patients with chronic hepatitis C, the biochemical markers usually improve rapidly during IFN alpha administration, but relapse if treatment is stopped after only a few months; to increase the chances of sustained cure, the treatment period is now being prolonged.

Hepatitis B virus replication within the human spleen

Southern blot analysis of splenic DNA from three patients with chronic hepatitis B revealed the presence of replicative intermediate forms of viral DNA. Hepatitis B viral RNA was detected in splenic RNA from two cases. Thus, hepatitis B virus appears to replicate in the human spleen, although at a lower level than in the liver.

Hepatitis B virus DNA in liver and peripheral blood mononuclear cells during reduction in virus replication

Changes in hepatitis B virus DNA in blood cells and liver were studied in 34 patients (12 controls, 22 under therapy). There were no basal differences in the presence of the viral genome in blood cells between treated and control patients. A significant decrease in the percentage of patients with viral genome in blood cells was observed in patients who lost this marker in serum. Replicative intermediates of the viral genome were observed in the basal liver samples from all patients. In patients who lost the viral DNA in serum, hepatitis B virus genome became undetectable in the second liver sample in all but two patients who had viral sequences integrated in the host genome. Replicative intermediates were found in all patients with serum viral DNA. The results of this study suggest that there may be a relation between the disappearance of hepatitis B virus DNA in liver and blood cells.

Interferon antibodies may negate the antiviral effects of recombinant alpha-interferon treatment in patients with chronic hepatitis B virus infection

In a randomized controlled trial of recombinant alpha-2a interferon for chronic hepatitis B, interferon antibodies developed in 21 (39%) of 54 Chinese adults who received IFN. No correlation was observed between sex, age, pretreatment serum ALT level or liver histological findings and the development of interferon antibodies. Antibodies were significantly more likely to develop in patients who received lower doses (2.5 or 5 MU/m2) of alpha-2a interferon than in those who received a higher dose (10 MU/m2): 53% vs. 11% (p = 0.006). The development of interferon antibodies appeared to reverse the initial antiviral response to treatment, with reappearance of hepatitis B virus DNA in serum in 12 patients and HBeAg in three patients. Sustained clearance of HBeAg was achieved in only one (5%) patient but was achieved in seven (21%) patients without interferon antibodies. The mere presence of interferon antibodies did not preclude an antiviral response to interferon therapy, but patients with high titer neutralizing antibodies were less likely to respond. These findings suggest that interferon antibodies may negate the antiviral effects of alpha-2a interferon. A higher incidence of interferon antibodies in Chinese vs. white patients with chronic hepatitis B may contribute to the poorer antiviral response in Chinese patients.

Immunological studies before and during interferon therapy in chronic HBV infection: identification of factors predicting response

Lymphoblastoid interferon is effective therapy in some but not all patients with chronic hepatitis B virus infection. To assess whether immunological parameters were predictive of response to interferon therapy, we determined the human leukocyte antigen type, CD4/CD8 ratio, natural killer cell activity, IgM anti-HBc antibody levels and concanavalin A-induced lymphocyte proliferative response in 30 patients before treatment. In addition, to investigate the mechanisms of action of interferon in promoting hepatitis B virus clearance, we serially measured the CD4/CD8 ratios, natural killer activity and lymphocyte proliferative response at wk 4, 8 and 12 of treatment. A beneficial response to therapy was defined as the sustained clearance of HBeAg and serum hepatitis B virus DNA within 1 yr of commencing therapy. Elevated IgM anti-HBc levels were associated with a beneficial response to therapy, but there was no correlation observed between response and pretreatment CD4/CD8 ratio, natural killer activity or lymphocyte proliferative response. Six of seven human leukocyte antigen DR3-positive patients responded. No measurable changes in the immunological parameters studied were observed in the nonresponder group, whereas a significant rise in CD4/CD8 ratio, associated with a fall in peripheral CD8 number and a decline in measurable NK activity, was seen in the responder group. These changes were maximal at the time of hepatitis B virus DNA clearance, which was associated with a transient increase in hepatic inflammation.(ABSTRACT TRUNCATED AT 250 WORDS)

The hepatitis B virus

Of all the hepatotropic viruses, HBV is associated with the greatest worldwide morbidity and mortality. This is because of the ease of transmission and the potential for progression to a chronic infective carrier state, with the complications of cirrhosis and hepatocellular carcinoma. The use of PCR has shown that some of the earlier concepts concerning the interpretation of serological data were inaccurate. Many patients with anti-HBe and anti-HBs have viral DNA detectable by PCR, and some hepatocellular carcinoma patients have detectable HBV DNA in their livers in the absence of all serological markers of HBV disease. The clearance of HBV infected cells from the liver is dependent on the interplay between the interferon system and the cellular limb of the host immune response. The importance of the nucleocapsid proteins as targets for sensitized cytotoxic T cells has been established for chronic HBV infection. The importance of pre-S sequences as inducers and targets of the virus-neutralizing humoral immune response is becoming established, but their precise role must await the development of in vitro models of hepadnavirus infection and a greater understanding of the mechanisms of viral uptake. The epidemiology and clinical course of the disease can be modified by immunization, immune stimulation and antiviral chemotherapy. For the developing world, a programme of immunization at birth would be the most effective way of eliminating this disease, but at present the cost is prohibitive. For the developed world, immunization is realistic for the at-risk population, and anti-viral and immunostimulatory therapy available for those already infected. In adult acquired chronic HBV infection alpha-interferon produces HBe antigen clearance in 40-60% of cases and is followed by resolution of the hepatic inflammation. Results in neonatally acquired infection are less impressive and prednisolone priming followed by interferon may be needed. The presence of a mutation in the pre-core region of some virus isolates has recently been described. Hepatocytes infected with this virus cannot produce HBe antigen and the course of the liver disease is fairly rapid. Whether this mutant causes liver damage in the same way as the wild virus or is directly cytopathic remains unclear, and its relationship to fulminant hepatitis is under investigation.

Detection of hepatitis B virus DNA in serum by polymerase chain reaction. Application for clinical diagnosis

Standard methods of virus DNA detection using the polymerase chain reaction can be time consuming and can involve multiple steps in which contamination with exogenous DNA can occur. Therefore, we developed a simplified method for detecting hepatitis B virus DNA in serum. The main advantages of this method are that it can be performed rapidly, consists of only several steps, and has a false positive rate of less than 0.1% in our laboratory. In testing serial samples from five chimpanzees experimentally infected with hepatitis B virus, we found that hepatitis B virus DNA was detected 2-3 weeks before the appearance of hepatitis B surface antigen, and it continued to be detectable 1-3 weeks after the production of antibody to hepatitis B surface antigen. In testing serum from 84 human patients, we found hepatitis B virus DNA in all patients who had hepatitis B surface antigen and hepatitis B e antigen in serum and in 64% of the patients with hepatitis B surface antigen with antibody to hepatitis B e antigen in serum. Also, 3 out of 11 patients who were chronic hepatitis B carriers and who subsequently lost hepatitis B surface antigen were found to test positive for hepatitis B virus in serum. In contrast, all patients who lost hepatitis B surface antigen after acute hepatitis B virus infection or those classified as having non-A, non-B hepatitis tested negative for hepatitis B virus DNA. Thus, the modified PCR technique is a sensitive and rapid method for detecting hepatitis B virus DNA-containing virions in serum.

A randomized, controlled trial of interferon alfa-2b alone and after prednisone withdrawal for the treatment of chronic hepatitis B. The Hepatitis Interventional Therapy Group

BACKGROUND AND METHODS

Chronic hepatitis B is a common and often progressive liver disorder for which there is no accepted therapy. To assess the efficacy of treatment with interferon, we randomly assigned patients with chronic hepatitis B to one of the following regimens: prednisone for 6 weeks followed by 5 million units of recombinant interferon alfa-2b daily for 16 weeks; placebo followed by 5 million units of interferon daily for 16 weeks; placebo followed by 1 million units of interferon daily for 16 weeks; or observation with no treatment.

RESULTS

Hepatitis B e antigen and hepatitis B viral DNA disappeared from serum significantly more often in the patients given prednisone plus interferon (16 of 44 patients, or 36 percent) or 5 million units of interferon alone (15 of 41; 37 percent) than in the untreated controls (3 of 43; 7 percent; P less than 0.001); the difference between those given 1 million units of interferon (7 of 41; 17 percent) and the controls was not significant. The strongest independent predictor of a response to treatment was the amount of hepatitis B viral DNA in serum at entry (P less than 0.0001). Of the 38 patients who responded to interferon, 33 (87 percent) had normal serum aminotransferase levels after therapy; 11 patients who responded (29 percent), but no controls, lost the hepatitis B surface antigen. Blinded histologic assessment revealed a significant improvement in periportal necrosis in the treated patients (P = 0.03).

CONCLUSIONS

In chronic hepatitis B, treatment with interferon alfa-2b (5 million units per day for 16 weeks) was effective in inducing a sustained loss of viral replication and achieving remission, assessed biochemically and histologically, in over a third of patients. Moreover, in about 10 percent of the patients treated with interferon, hepatitis B surface antigen disappeared from serum.