Since the circulating influenza strains for any given season cannot be precisely predicted, an effective influenza vaccine should be able to generate protection for both the genetically identical (homologous) strain of flu as well as genetically-drifted (heterologous) strains. This is even more important in the case of vaccines developed against avian influenza (so called bird flu) where the human strain cannot be precisely predicted from the strains circulating in the bird population. For the first time in humans, DNA-based vaccines and immunotherapeutics company PowderMed has shown that its H3/Panama DNA-based influenza vaccine shows cross-protective immunity against both an homologous H3 flu strain as well as four drifted heterologous H3 strains. This suggests that the vaccine could be particularly useful in providing a means of vaccinating against emerging variants of annual influenza. Importantly, these results also provide evidence that PowderMed’s vaccine approach may be particularly useful in addressing potential pandemics from avian influenza (bird flu).
