Approach to the management of patients with chronic hepatitis C who failed to achieve sustained virologic response

Chronic hepatitis C

The goal of antiviral therapy for patients with chronic hepatitis C virus (HCV) infection is to attain a sustained virologic response (SVR), which is defined as undetectable serum HCV-RNA levels at 6 months after the cessation of treatment. Major improvements in antiviral therapy for chronic hepatitis C have occurred in the past decade. The addition of ribavirin to interferon-alfa therapy and the introduction of pegylated interferon (PEG-IFN) have substantially improved SVR rates in patients with chronic hepatitis C. The optimization of HCV therapy with PEG-IFN and ribavirin continues to evolve. Studies are ongoing that use viral kinetics to tailor therapy to an individual's antiviral response and determine the ideal length of treatment to maximize the chance of SVR. Improved SVR can be achieved with new specific inhibitors that target the HCV NS3/4A protease and the NS5B polymerase. Several long-term follow-up studies have shown that SVR, when achieved, is associated with a very low risk of virologic relapse. Furthermore, antiviral therapy can reduce the morbidity and mortality rates associated with chronic hepatitis C by reducing fibrosis progression, the incidence of cirrhosis, and hepatocellular carcinoma.

Elevated hepatic transaminases associated with the use of interferon alfacon-1 and ribavirin

PURPOSE

The case of a patient with hepatitis C who developed elevated hepatic transaminase levels associated with the use of interferon alfacon-1 and ribavirin is described.

SUMMARY

A 55-year-old Caucasian man arrived at a hepatitis C clinic to discuss alternative treatment options for his hepatitis C virus (genotype 1a) infection, which did not respond to a 48-week course of peginterferon and ribavirin therapy. He was subsequently treated with interferon alfacon-1 9 microg subcutaneously daily plus ribavirin 200 mg orally twice daily. During treatment with interferon alfacon-1, he developed elevated hepatic transaminase levels despite a decrease in viral load. His hepatic transaminase levels returned to baseline when interferon alfacon-1 was discontinued and rose again upon rechallenge. Ribavirin was not the likely cause of the increase in transaminases since the patient previously tolerated it in combination with peginterferon. While activation of autoimmune hepatitis is a potential cause of acute decompensation in patients treated with interferons, it was not believed to be the case in this patient. Interferon alfacon-1 was determined to be the probable cause of the rise in hepatic transaminase levels in this patient, since his levels declined when therapy was discontinued and rose dramatically once it was restarted. This case illustrates the importance of monitoring both viral loads and hepatic transaminase levels in patients with hepatitis C being treated with interferon therapy.

CONCLUSION

A patient with hepatitis C developed elevated hepatic transaminase levels despite showing an improvement in viral load after receiving interferon alfacon-1 and ribavirin.

Optimizing the current therapy for chronic hepatitis C virus: peginterferon and ribavirin dosing and the utility of growth factors

Achieving a sustained virologic response depends on the patient achieving three sequential independent milestones: virologic response, maintaining this response throughout treatment, and not relapsing after treatment has been completed. The ability to achieve these milestones depends on the doses of interferon/peginterferon and ribavirin used and on whether treatment with these medications is adjusted, interrupted, or prematurely discontinued in response to adverse events. This review discusses strategies to optimize peginterferon and ribavirin dosing and the impact that growth factors may have on the ability to achieve a sustained virologic response.

Triple antiviral therapy in HCV positive patients who failed prior combination therapy

AIM: To assess the efficacy of triple therapy (peginte-rferon or high dose standard interferon, plus ribavirin and amantadine) in nonresponders to prior combination therapy.

METHODS: A total of 196 patients were enrolled in a multicenter, open, randomized study. Patients were given 180 μg/wk of peginterferon-alpha-2a (40 kDa) plus ribavirin (800-1000 mg/d) and amantadine (200 mg/d) for 48 wk (group A) or interferon-alpha-2a (6 MU/d for 4 wk, 3 MU/d for 20 wk, and 3 MU tiw for 24 wk) plus ribavirin (800-1000 mg/d) and amantadine (200 mg/d) for 48 wk (group B).

RESULTS: Overall sustained virologic response (SVR) was 26.6% (32.1% and 19.5% in group A and B, P = 0.057). Baseline ALT >120 UI/L (OR 2.4; 95% CI:1.11 to 5.20; P = 0.026) and HCV RNA negativity after 12 wk (OR 8.7; 95% CI: 3.87 to 19.74; P < 0.0001) were independently associated with SVR. Therapy discontinuation occurred less frequently in patients treated with peginterferon than standard interferon (P = 0.036).

CONCLUSION: More than 25% of nonresponders to combination therapy can eradicate HCV infection when retreated with triple therapy, especially if they have a high baseline ALT and are treated with pegylated interferon.

Histamine dihydrochloride: actions and efficacy in the treatment of chronic hepatitis C infection

The host immune response, in addition to viral factors, is the critical determinant of the pathological consequences of hepatitis C virus infection. Current therapies for genotype 1 are unsuccessful in a substantial number of patients. Histamine dihydrochloride by virtue of its histamine H2 agonistic activity, has the potential to prevent damage induced by oxidative stress in tissues and can protect T and natural killer lymphocytes from oxygen radical-induced functional inhibition and apoptosis, thereby, potentiating interferon-alpha-induced activation of these cells. Coadministration of histamine dihydrochloride and interferon therapy for chronic hepatitis C virus infection was tested in several clinical trials. However, conflicting data and the relatively small numbers of patients enrolled, suggest that this combination should be the focus of further investigation.

Treatment of chronic HCV infection in special populations

The mainstay of treatment of chronic hepatitis C is pegylated interferon combined with ribavirin and more than 50% of naïve patients will have viral cure with either 6 months (genotypes 2 and 3) or 12 months (genotypes 1,4, and 6) with the initial treatment. However, populations have been defined that respond less well to routine treatment including African Americans, immune suppressed populations, obese patients and cirrhotic patients. These types of patients are enriched in groups of patients who are non-responders to treatment. This article discusses viral kinetics that may impact treatment response, strategies to maximize treatment effectiveness in these populations and the treatment of non-responders in general. Early viral kinetics can be used to define response or non-response and these results can be used to modify subsequent treatment length and dose.

Chronic hepatitis C: treatment of pegylated interferon/ribavirin nonresponders

Patients with chronic hepatitis C virus (HCV) who were nonresponders to previous treatment with pegylated interferon and ribavirin are a growing population. The vast majority have genotype 1, a high viral load, advanced fibrosis or cirrhosis, and are of African-American race. The evaluation of these patients should include a thorough review of the previous treatment record and characterization of the previous nonresponse. Patients with prior null response are likely resistant to the effects of interferon. In contrast, patients with partial virologic response, breakthrough, and relapse could potentially achieve sustained virologic response if one or more correctable factors that contributed to the prior nonresponse are identified and addressed before and during retreatment. Many HCV nonresponders, especially those with no fibrosis or mild fibrosis, have an excellent prognosis, are at low risk to develop cirrhosis, and should simply be monitored at periodic intervals until more effective therapy has been developed.