Abstract IA16: Prevention of hepatocellular carcinoma through preventative hepatitis C vaccination

In the United States, the incidence of hepatocellular carcinoma (HCC) has tripled and mortality rates have doubled since 1980. Between 2006 and 2015, HCC diagnoses increased by approximately 3% annually. Liver cancer is the fifth most common cause of cancer death in men and the seventh among women. Hepatitis C virus (HCV) infection is the primary risk factor for about one-third of cases of HCC in the US population. Hepatitis C virus (HCV) infection is a bloodborne disease with global distribution that affects almost 3% of the world’s population. Less than 20% of acute HCV infections cause acute viral hepatitis symptoms severe enough for the patient to seek medical care, and approximately 75% of all infections become persistent. Individuals with chronic HCV infection usually remain asymptomatic and undiagnosed for decades before chronic hepatitis leads to complications that can include severe fibrosis and cirrhosis, hepatic failure, or HCC. In studies of people with HCV, the risk for HCC increased as much as 3% per year after diagnosis of cirrhosis. Despite effective therapy, HCV remains the leading cause of liver failure requiring transplantation and HCC in many countries. Continuing advances in therapeutic regimens are promising for effecting cures of HCV and may reduce transmission. However, there remain challenges in HCV control. Identifying those with HCV infection is difficult because of its relative silence until end-stage disease develops. It is estimated that fewer than 5% of HCV-infected persons are diagnosed worldwide, and the proportion of patients who access and complete treatment remains low. Even when current HCV therapy is administered successfully, it does not provide immunity against subsequent infection. Intravenous drug users and other high-risk groups, such as health care providers, those living in endemic regions, and HIV-infected men who have sex with men, are at risk for new infections and will continue to be at increased risk of infection despite better regimens for HCV treatment. HCV transmission is likely to persist in areas with limited access to antiviral drugs and poor needle injection and blood product hygiene. These challenges, as well as the cost of therapy, make HCV therapy alone unlikely to block the spread of infection within the total human population and to eradicate HCV. In contrast, in Taiwan immunization of infants against hepatitis B virus (HBV) has substantially reduced HBV transmission and subsequently the risk of developing HCC as children and young adults. Therefore, development of a vaccine to prevent chronic HCV infection, if not to prevent infection altogether, remains a critical aspect of an HCV disease control platform. This talk will discuss the need for a vaccine, the evidence that a vaccine to prevent chronic infection is possible, and the vaccine strategies tested to date. Citation Format: Andrea L. Cox. Prevention of hepatocellular carcinoma through preventative hepatitis C vaccination [abstract]. In: Proceedings of the AACR Special Conference on the Microbiome, Viruses, and Cancer; 2020 Feb 21-24; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2020;80(8 Suppl):Abstract nr IA16.