Vaccines are an effective way to prevent influenza infection. Each year the World Health Organization (WHO) and the U.S FDA recommend the influenza strains to include in the seasonal influenza vaccines. The licensed seasonal influenza vaccines are directed against 3 influenza virus strains: an influenza A H1N1, an influenza A H3N2, and an influenza B. The currently approved vaccines depend upon labor-intensive methods that limit manufacturing speed and capacity. Influenza vaccines that can be more rapidly produced and that induce stronger, broader and more persistent immune responses are a recognized public health need.
In this protocol we propose to use DNA vaccine antigen delivery to induce immune responses against native hemagglutinin (HA) structures prior to boosting with licensed TIV ID or with TIV IM.
The study will allow evaluation of the safety and immunogenicity of same season and sequential season vaccination schedules. The same season regimens (2012/13 prime and boost with a 14 week interval) consist of HA DNA prime with TIV ID boost -- or -- HA DNA prime with TIV IM boost. The active comparator for these schedules are TIV ID or TIV IM alone because a single dose of TIV is the standard for adult influenza vaccination within a single season. The sequential season regimens (2012/13 prime and 2013/14 boost) consist of concurrent administration (in different arms) of HA DNA and TIV ID prime with TIV ID boost -- or -- HA DNA and TIV IM prime with TIV IM boost. The active comparator for these regimens will be TIV ID followed by TIV ID boost -- or -- TIV IM followed by TIV IM boost, administered sequential seasons consistent with as typical pattern of use for these licensed vaccines. Evaluation of the investigational schedules and active comparator schedules will inform development of novel influenza vaccine strategies that may offer improved and cross-protective immunity against diverse influenza strains.