The study was part of the company’s program to develop a DNA vaccine that could ultimately protect humans against emerging strains of avian flu that could cause a pandemic. Funding for the study was included under a grant from the US National Institutes of Health (NIH).
The DNA vaccines tested in mice targeted highly-conserved influenza proteins – nucleoprotein (NP) and matrix protein (M2) – and were systematically tested with Vaxfectin and other formulations.
Vaxfectin-formulated vaccines demonstrated statistically superior protection in mice, particularly at low doses, against lethal challenges with H1N1 or H3N2 strains of human influenza.
The program has advanced to lethal challenge testing in mice and ferrets with the H5N1 strain of avian influenza in BSL-3 facilities at St Jude Children’s Research Hospital. Results from testing of Vaxfectin-formulated vaccines targeting NP, M2 and H5, are expected to be available in the second half of 2006.
“Our pandemic influenza vaccine program has advanced rapidly from initial concept, through lethal challenge testing against human flu strains in animals, to lethal challenge testing against the H5N1 avian flu strain in animals,” said Dr David Kaslow, Vical’s chief scientific officer. “The human flu strain challenge data confirmed the concept of cross-protection via low-dose, Vaxfectin-formulated DNA vaccines targeting conserved influenza proteins, and drove our design of vaccines for the avian influenza challenge studies.”