Interferon-alpha 2b plus ribavirin in patients with chronic hepatitis C after liver transplantation: a randomized study

Treatment of recurrent hepatitis C after liver transplantation: a pilot study of peginterferon alfa-2b and ribavirin combination

BACKGROUND/AIMS

After liver transplantation (LT) for HCV-related cirrhosis, recurrence of HCV infection is universal and the risk of progression to cirrhosis is high. The modalities and efficacy of antiviral therapy in this indication are still controversial. We present here the results of a pilot study of a 12-month combination therapy by pegylated alfa 2b-interferon (PEG-IFN) and ribavirin in 20 patients.

METHODS

Twenty patients entered the study (13 male and 7 female, median age 53.8 years). In 80% of patients, HCV infection was of genotype 1. The delay between LT and antiviral therapy was 28 months. The doses were progressively increased from 0.5 to 1 micro g/kg/week for PEG-IFN and from 400 to 1000-1200 mg/d for ribavirin. Follow-up was based on biochemical (ALT), virological (HCV-RNA) and histological (liver biopsy) examinations.

RESULTS

Four patients (20%) were withdrawn due to adverse effects. In 6 patients the dose of PEG-IFN had to be reduced to 0.5 micro g/kg/week. A reduction in the dose of ribavirin in 13/16 cases was due to the onset of anemia. Histological evidence of mild acute rejection increased the immunosuppressive regimen in 5/20 patients. At the end of the treatment, 75% of the patients had a biochemical response and 55% a virological response. The mean METAVIR score, according to activity and fibrosis, was A1.8 F2.2 before treatment and A0.3 F1.6 at the end of treatment. In 9/20 patients, virological response persisted 6 months after the end of the treatment.

CONCLUSIONS

Our results suggest that combination therapy by PEG-IFN and ribavirin may be well tolerated and beneficial during recurrent hepatitis C in liver transplant recipients.

Impact of cyclosporine on the development of immunosuppressive therapy in liver transplantation

Over the last 20 years, immunosuppression protocols in liver transplant patients have been based on calcineurin inhibitors, such as cyclosporine (CsA). Currently, there are three outstanding clinical issues related to the use of CsA in the liver transplant setting that merit further attention: (1) dose adjustment according to 2-hour postdose (instead of trough) concentrations to improve efficacy and safety, (2) possible synergistic effect between CsA and antiviral treatments for recurrent posttransplant hepatitis C infection, and (3) preliminary results showing favorable outcomes after liver transplantation in HIV-positive patients receiving antiviral therapy.

Treatment of hepatitis C virus in the liver transplant recipient

Significant necroinflammatory and/or fibrotic histologic changes should prompt consideration of antiviral therapy in liver transplant recipients with chronic hepatitis C. Depending on the patient, consideration of lower-dose pegylated interferon initially, with an increase to standard doses over the course of 1 month, may improve patient compliance and tolerance. The use of growth factors to prevent anemia and leukopenia is encouraged. Liver transplant recipients should be treated for at least 1 year, until data are available on optimal duration of therapy in non-genotype 1 patients in this patient subpopulation.

How can we identify better those with recurrent hepatitis C who will respond to therapy? What are the optimal treatment regimen and treatment duration?

1. Treatment responses are lower in immune compromised patients such as those with hepatitis C virus (HCV) disease following liver transplantation than in immune competent patients with HCV disease. 2. Predictors of nonresponse, extrapolated from studies of immune competent patients, are overly represented in liver transplantation patients (high levels of HCV RNA and genotype 1 infection). 3. Tolerability of peginterferon plus ribavirin therapy is lower in transplant patients than in immune competent patients with HCV disease, in part because of a baseline renal insufficiency that increases the likelihood of ribavirin-associated anemia. 4. Clear recommendations regarding optimal treatment regimens for patients with posttransplantation HCV disease are problematic since there are few prospective, randomized, controlled trials that evaluated different treatment regimens. 5. If treatment is undertaken, baseline creatinine clearance should be measured and patients should be started on a dose of ribavirin of 400mg bid, or lower if renal function is impaired. 6. Tolerated peginterferon doses may be somewhat lower than for the standard immune competent patients. It is likely that lower doses will not greatly compromise response (1.0 ug/kg/week for peginterferon alfa 2b and 135 ug/week for peginterferon alfa 2a). 7. Optimal treatment duration is unknown. In patients with an on-treatment response, at least 12 months of therapy is recommended. 8. More potent drugs with fewer toxicities are needed for patients with progressive posttransplantation liver disease.

The clinical and immunologic impact of using interferon and ribavirin in the immunosuppressed host

1. Allograft infection with hepatitis C virus (HCV) in immunosuppressed adults results in decreased allograft and patient survival. 2. Risk factors for accelerated progression of hepatitis C related to immunosuppression include treated episodes of acute cellular rejection (ACR), pulse therapy with methylprednisolone, and use of OKT3. 3. Both interferon alfa (IFN-alpha) and ribavirin (RVN) show antiviral actions against HCV and stimulate innate and adaptive immunity to increase cytolysis and polarize T helper subtype 1 (T(H)1) responses. In addition, IFN-alpha inhibits fibrogenesis in the liver. 4. Both IFN-alpha and RVN have been studied in immunosuppressed liver transplant recipients as prophylaxis or treatment of established hepatitis C to reduce allograft failure and patient mortality. Reported protocols include monotherapies with RVN, standard IFN-alpha, and pegylated IFN-alpha and combination therapies using RVN and either standard IFN-alpha or pegylated IFN-alpha. 5. The clinical impact of using IFN-alpha and RVN in highly selected immunosuppressed patients varied among studies. Combination therapy with standard IFN-alpha and RVN resulted in the greatest sustained biochemical and virological responses. However, no therapy prevented progression of acute cholestatic hepatitis C despite evidence of virological responses. Substantial proportions of patients developed adverse events requiring dose reduction or discontinuation that compromised efficacy. RVN monotherapy was not only virologically ineffective, but may have stimulated hepatic fibrosis. Current data regarding monotherapy or combination therapy with pegylated IFN-alpha are limited, but encouraging. 6. Despite potent immunostimulatory actions of both IFN-alpha and RVN that enhance natural killer, T(H)1, their use did not significantly increase the incidence of ACR. 7. Additional studies are needed to resolve the controversy over prophylaxis versus treatment of established disease and the potential utility of low-dose maintenance IFN-alpha therapy to retard fibrogenesis without clearing HCV. 8. After new, less toxic, and more potent antiviral agents become available, they should be tested immediately in patients with hepatitis C post-liver transplantation.

Delayed onset of severe hepatitis C-related liver damage following liver transplantation: a matter of concern?

Although histological hepatitis occurs in the majority of hepatitis C virus (HCV)-infected liver transplant recipients, the natural history is highly variable. Whereas progression to cirrhosis occurs in up to 30% after 3 to 7 years, the disease remains stable in another third of patients, in whom protocol liver biopsies might be avoided. However, there is recent concern that with prolonged follow-up, some patients with initial benign recurrence may develop a late-onset aggressive course. Aims of the study are to determine the incidence and factors associated with this event. Based on yearly protocol biopsies (median, five biopsies; range, three to seven biopsies), we evaluated the histological outcome of 57 HCV type 1b-infected transplant recipients with initial benign recurrence, defined as stable histological state (fibrosis stage F0 or F1) during the first 3 years posttransplantation. Severe late-onset liver damage is defined as progression to F3 or F4 in patients with previous benign recurrence. Potential predictors of this event include demographics, donor-related factors, liver enzyme levels at 1 and 3 (or baseline) years posttransplantation, activity grade and fibrosis stage at 1 and 3 years posttransplantation, nonalcoholic steatohepatitis-related variables occurring within the first 3 years posttransplantation (diabetes, hyperlipidemia, obesity), use of some drugs (renin-angiotensin inhibitors, ursodeoxycholic acid), and the advent of any unusual event. The incidence of severe late-onset liver damage was 35% (n = 20). Twelve transplant recipients progressed to F3, whereas 8 transplant recipients progressed to F4. Sudden histological deterioration was observed on postoperative biopsy 5 in 12 patients; biopsy 6 or 7, in 7 patients; and biopsy 4, in 1 patient. Variables associated with this event in univariate analysis were fibrosis stage and activity grade (and its components) at baseline (P <.0001), recipient female gender (P =.04), alanine aminotransferase (ALT) level at 1 year posttransplantation (P =.02), and aspartate aminotransferase (AST) and ALT levels at baseline (P =.008 and P =.005, respectively). By multivariate analysis, only one variable was retained in the model: fibrosis stage at baseline (relative risk, 11; 95% confidence interval, 3 to 41; P =.0007), whereas AST level almost reached statistical significance (P =.07). In conclusion, delayed HCV-related severe liver damage is not infrequent in transplant recipients with initial benign recurrence, occurring in approximately one third of them. The presence of some degree of fibrosis at baseline appears to predict this sudden change in the natural history of recurrent hepatitis C. Based on these findings, we recommend continuing protocol biopsies and evaluating potential antiviral therapy in transplant recipients with evidence of some fibrosis (even if it is only portal).

Controversies in the management of hepatitis C virus infection after liver transplantation

Recurrence of hepatitis C virus infection after liver transplantation is universal. A significant percentage of these patients develop progressive graft injury and cirrhosis. Those factors that modulate disease progression in liver transplant recipients with recurrent hepatitis C virus infection remain controversial and are poorly understood. Treatment of recurrent hepatitis C virus after liver transplantation with either interferon or interferon and ribavirin has yielded only limited success. Regardless of this, treatment is instituted. Peginterferon is more effective than standard interferon for treatment of chronic hepatitis C virus infection in the nontransplantation setting when used either alone or with ribavirin. The effectiveness of peginterferon, both with and without ribavirin in the posttransplantation setting, is currently being explored. In this review those factors thought to affect disease progression in patients with recurrent hepatitis C virus will be discussed, strategies that have been used to treat recurrent hepatitis C virus will be reviewed, and the impact that peginterferon may have on hepatitis C virus infection in the pretransplantation and posttransplantation setting will be explored.

Antiviral therapy of patients with decompensated cirrhosis to prevent recurrence of hepatitis C after liver transplantation

BACKGROUND/AIMS

After liver transplantation (LT) infection of the graft with the hepatitis C virus (HCV) is almost universal and chronic hepatitis and cirrhosis develop in a significant proportion of patients. One of the possible strategies to prevent HCV infection recurrence is to eradicate HCV before LT.

METHODS

We evaluated the efficacy and safety of antiviral therapy to prevent HCV recurrence in 30 HCV-cirrhotic patients awaiting LT. At the time of inclusion 15 patients were Child-Pugh A and 15 Child-Pugh B/C. The infecting genotype was 1b in 25 patients. Treatment with interferon alpha-2b 3 MU/day and ribavirin 800 mg/day was initiated when the expected time for LT was less than 4 months and continued until LT. The median duration of treatment was 12 weeks.

RESULTS

Nine patients (30%) achieved a virological response and 21 did not respond to therapy. In nine (43%) of the 21 non-responders viral load decreased > or =2 log10 during treatment. A viral load decrease > or = 2 log10 at week 4 of treatment was the strongest predictor of virological response. All nine virological responders have already undergone LT; six patients remain free of infection after a median follow-up of 46 weeks and HCV infection recurred in three patients after LT. In one of these patients HCV-RNA was still detectable in the explanted liver. Side effects were frequent and dose reduction was necessary in 19 (63%) of the 30 patients; no patient died while on therapy.

CONCLUSIONS

Our data support the utilization of antiviral therapy in HCV-infected patients awaiting LT as one of the strategies to prevent hepatitis C recurrence after transplantation.