Inovio Pharmaceuticals announced that its synthetic hepatitis B, or HBV, therapeutic vaccine generated strong T cell responses that eliminated targeted liver cells in mice. This data points to the DNA vaccine's potential to clear HBV infection and thereby prevent liver cancer in humans, an encouraging development given that nearly one-third of the world's population is infected with hepatitis B, with 400 million at risk of developing liver cancer. In the study, Inovio researchers and collaborators constructed a DNA vaccine encoding an HBV core antigen using the SynCon vaccine technology and administered it via Inovio's proprietary electroporation-based delivery technology. Researchers observed that the vaccine induced strong "killer" T cells in an animal model. Importantly, those killer T cells, while found systemically, were also present in the liver and provided clearance of HBV antigen-expressing liver cells without inducing liver damage. The company is also investigating additional HBV antigens to develop a multi-component vaccine that can provide the host immune system multiple targets to clear the hepatitis B virus and infected liver cells.