The Stage 1 dose-escalating clinical study is designed to measure the security, tolerability and pharmacokinetics of CMX157. In addition to monitoring security and regular PK parameters in plasma, levels of the active antiviral will be determined in peripheral blood mononuclear cells . These data provides insight into the potential efficacy of CMX157, as the levels of tenofovir diphosphate in PBMCs linked to the antiviral efficacy of Viread have already been documented.Dr. Wei says the effective immune response against HER2-positive receptors observed in the study works actually in tumours that are resistant to current therapies and the vaccine possibly has the potential to remove the need to use the therapies. The researchers say the vaccine consists of ‘naked’ DNA – genes that create the HER2 receptor – as well as an immune stimulant, both housed in a inert bacterial plasmid. The researchers used pulses of electricity to deliver the injected vaccine into leg muscles in mice, where in fact the gene produced a huge quantity of HER2 receptors that activated both antibodies and killer T cells.