Jun 7, 2006 (CIDRAP News) – Vical Inc., San Diego, announced today it would receive early access to $2.6 million in government funds to help it complete preclinical development of a DNA vaccine for avian influenza.
Last September the National Institute of Allergy and Infectious Diseases (NIAID) awarded the company a $2.9 million challenge grant to develop the vaccine. In May the company reported the vaccine had protected mice and ferrets against a highly virulent strain of H5N1 avian flu virus and had protected mice against multiple human flu strains.
On the basis of those results, the National Institutes of Health notified Vical that it had achieved the second milestone required under the challenge grant, the company said in a news release today.
The new funds will be used to finish preclinical work on the vaccine and apply to the US Food and Drug Administration for permission to launch a phase 1 clinical trial, the company reported. The firm is seeking additional funds to support the phase 1 trial.
DNA vaccines use small pieces of the target pathogen's genetic material instead of a killed or weakened form of the whole pathogen. Vical says it makes DNA vaccines with simple bacterial fermentation methods that may allow rapid production of large amounts.
David C. Klaslow, MD, Vical's chief scientific officer, said the company's DNA flu vaccines "have performed remarkably well in animal challenge studies, and this accelerated access to funding allows us to move forward ahead of our original schedule, which is quite important given the imminent threat posed by pandemic influenza."
The company has been collaborating with St. Jude Children's Research Hospital in Memphis in the early development of the DNA flu vaccines. In reporting the results of animal experiments last month, the company said its three-component vaccine fully protected mice and ferrets against death and weight loss after exposure to an H5N1 virus, whereas animals that received a control vaccine all died. The three-component vaccine targeted one of the virus's variable surface proteins and two conserved, or stable, core proteins, the company said.
The company also said it tested DNA vaccines targeting only the two conserved viral proteins. In that study, 14 of 16 mice in each of two vaccine groups survived with moderate weight loss. "The study is the first to provide evidence that a vaccine targeting conserved influenza virus proteins without matched surface proteins can provide protection against such a highly virulent H5N1 flu strain," the company said in a May 2 news release.
In addition, the firm said the same vaccine formulation protected animals against two strains of human influenza in a previous study.
"A vaccine that provides cross-protection against more than one strain of flu is important for addressing a pandemic flu threat because it is likely that the H5N1 virus could mutate before it becomes transmissible from human to human," said Richard Webby, PhD, of St Jude Children's Research Hospital, as quoted in a Vical release.
When Vical first announced its NIAID grant last September, it said its goal was "to design a vaccine that could be developed and manufactured quickly and safely, without handling the infectious organism, and stockpiled longer than conventional vaccines."
Jun 2 CIDRAP News story "Epidermal DNA flu vaccine shows promise in phase 1 trial"