During the experiments, 100% of the ferrets treated with VGX-3400 survived, while 100% of the control animals died. Vaccination with VGX-3400 generated potent neutralizing antibody and cell-mediated immune responses in four separate animal models – mice, ferrets, pigs, and rhesus monkeys. More specifically, VGX-3400 induced protective levels of hemagglutination inhibition (HAI) titers in 100% of the immunized animals for all four models. VGX-3400 also induced significant levels of antigen-specific CD8+ killer T cell responses.
All vaccines used were delivered with VGX’s patented Cellectra DNA delivery device. The results of both challenges strongly support an investigative new drug (IND) application for VGX-3400, which the company expects to file by the second quarter of 2008.
VGX said that its SynCon DNA vaccine antigens are designed by aligning numerous primary sequences and choosing the most common amino acid or base pair at each site by using high-powered and patented bioinformatics approaches. The SynCon DNA vaccines in combination with the Cellectra delivery device, the company says, provide greater levels of cross-reactive immune responses than those produced by more traditional vaccines.
Joseph Kim, president and CEO of VGX, said: “Our data further demonstrates the potential of our DNA vaccine and delivery approaches in addressing a significant global health problem. VGX-3400 is just the first step in executing our strategy for developing a universal flu vaccine.”