Development of an assay for quantitative detection of HBV cccDNA

Development of an assay for quantitative detection of cccDNA This SBIR application is in response to the Funding Opportunity Announcement FOA PA New Technologies for Viral Hepatitis SBIR R R more specifically to Develop genetic tests that might help in patient management of viral hepatitis including tests that assess the risk of complications as well as likelihood of success of specific therapies There is an urgent and unmet need for an effective method to detect hepatitis B virus HBV cccDNA in serum HBV infection affects nearly million people worldwide and chronic infection is a major risk factor for development of cirrhosis and hepatocellular carcinoma which has a poor survival rate Current therapies are effective at suppressing viral replication although they do not eliminate the virus due to the persistent viral replication intermediate known as covalently closed circular DNA cccDNA that serves as a template for generation of progeny virus This plasmid like episome that resides in the host nucleus is produced from relaxed circular DNA rcDNA a partially double stranded DNA found in circulating virions and transmitted into the host hepatocytes The need to remove cccDNA to cure HBV infection has prompted drug discovery groups to focus efforts on developing compounds that can target and eliminate cccDNA However the absence of a quantitative reliable cccDNA assay that is highly sensitive obtainable from serum and not contaminated by detection of the highly analogous rcDNA is needed to facilitate the drug development and to monitoring cccDNA level in the blood of HBV infected patient under anti viral therapy with repeated liver biopsies The goal of this project is to develop an innovative sensitive cccDNA assay that overcomes these challenges and would be suitable for routine testing by physicians We have designed such an assay and our preliminary studies have indicated specific detection of copies of cccDNA and no detectable amplification of copies of rcDNA Two aims are proposed in this phase I application Aim is to develop this prototype assay to be quantitative and sensitivity of of cccDNA to rcDNA Aim is to demonstrate the detection of cccDNA in serum of patients with HBV infection and correlate this detection with HBV surface antigen HBsAg In phase we will further develop and evaluate the assay for monitoring of therapeutic efficacy and extent of liver damage PUBLIC HEALTH RELEVENCE HBV infection places nearly million people globally at risk for development of cirrhosis and subsequent hepatocellular carcinoma HCC which is the third leading cause of cancer worldwide and has one of the highest recurrence rates A cure for HBV is now recognized as a treatment that can completely eliminate cccDNA Development of such therapies will require suitable companion diagnostics to monitor the persistence of cccDNA The goal of this phase project is to develop a highly sensitive cccDNA assay that can accurately detect cccDNA from a serum sample