Vical’s flu vaccine produces positive preclinical results

A study of Vical’s influenza DNA vaccine, formulated with the company’s patented Vaxfectin adjuvant, protected mice against lethal challenges with two different strains of human influenza virus.

The investigation 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 previously announced grant from the National Institutes of Health.

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.

“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.”