Role of IL28B genotype in older hepatitis C virus-infected patients

The average age of hepatitis C virus(HCV)-infected individuals is becoming increasingly higher in Japan and steps should be taken to treat older individuals infected with HCV. Until an interferon-free regimen becomes available, peginterferon plus ribavirin will play a critical role in the treatment. The perception that older HCVinfected patients may be at higher risk than younger patients for adverse events from peginterferon plus ribavirin treatment but may obtain less clinical benefit from it may be based on the underrepresentation of older patients in clinical trials. A recent genomewide association study revealed that interleukin-28B(IL28B) genotype closely correlates with the treatment response against HCV. The relationship of IL28 B genotype with the treatment response in older HCV-infected patients is also unknown. In this review, we focused on the treatment response in older patients infected with HCV and the effects of IL28 B genotype. IL28 B major genotype is a useful predictor of sustained virological response in the interferon-including treatment of older patients infected with HCV. It also seems useful for avoiding adverse events, although the mechanisms ofthe effects of IL28 B genotype on the treatment outcome are still poorly understood and are currently under investigation. Further studies will be needed.