Retreatment of chronic hepatitis C: who and how?

All but about 10% of patients with chronic hepatitis C (CHC) (predominantly those infected with genotype 1) can respond to some degree to 'combination' therapy with interferon (IFN) and ribavirin. The slower the virological response to treatment, the less likely sustained viral clearance will take place. Many factors influence response to antiviral therapy; most cannot be reversed (e.g. sex, age, cirrhosis, genotype and viral load). A sustained viral clearance is considerably facilitated by compliance with full-dose therapy for the prescribed time. The potential cause(s) for non-response need(s) to be ascertained before attempting retreatment. The 10% of patients who are true 'null' responders may respond to the new specifically targeted antiviral therapies but whether the response can be sustained off-therapy is unclear. Adjunctive therapies may facilitate response to retreatment if intolerance to treatment leading to diminished or absent doses was problematic in the past. Retreatment with a long-acting IFN and an adequate ribavirin dose (15 mg/kg), but given for 72 weeks in prior relapsers following 48 weeks of treatment, will enhance sustained virological response (SVR) rates. No benefit is gained from changing one pegylated IFN alpha (PEG IFN alpha) to another unless the treatment duration is extended. Only alpha-interferons are effective. For those individuals who still fail to achieve SVR, recruitment to trials of new treatments should be encouraged particularly for those with advanced liver disease. Lifestyle modification may be appropriate in attempt to reduce the chance of complications of liver disease, namely hepatocellular carcinoma, by smoking cessation, eliminating obesity and increasing coffee consumption.