Prevention of hepatitis C virus infection and liver cancer.

Hepatocellular carcinoma (HCC) is the fifth most prevalent cancer and the third leading cause of cancer-related death, and its incidence is increasing. The majority of HCC cases are associated with chronic viral hepatitis. With over 170 million individuals chronically infected with hepatitis C virus (HCV) worldwide, HCV is currently a serious global health concern, leading to chronic hepatitis, cirrhosis and HCC, thereby causing significant morbidity and mortality. With the incidence of HCV infection increasing, the problem of HCV-associated HCC is expected to worsen as well, with the majority of HCCs developing in the setting of cirrhosis. Thus, it is imperative to provide antiviral therapy to infected individuals prior to the development of established cirrhosis in order to reduce the risk of subsequent HCC. Indeed, the successful eradication of HCV is associated with clinical and histological improvement as well as a greatly reduced risk of subsequent HCC development. Even after the development of cirrhosis, successful viral clearance is still associated with reduced HCC risk. Current standard of care antiviral treatment consists of pegylated interferon-α and ribavirin, but viral clearance rates are suboptimal with this regimen, especially in difficult to treat cohorts. However, there is a myriad of different classes of HCV-specific direct-acting antiviral agents currently in development, which can be used in combination with one another or with standard of care treatment to improve HCV cure rates. Preventative and therapeutic vaccines against HCV remain an area of ongoing research with good progress towards developing an effective vaccine in the future.