Not all DNA vaccine manufacturers are using electroporation as a delivery method. Vical, the first company to produce a vaccine against the pandemic influenza A(H1N1) virus after initial reports of outbreaks in Mexico, uses a patented adjuvant known as Vaxfectin, “which does an amazing job of protecting the DNA before it enters the skeletal muscle cells,” Mr. Samant said. “Being a proinflammatory, it attracts the immune system toward the site of the injection to facilitate creation of the right immune response and immune memory.”
Phase I Trials Begin
On Oct. 1, 2009, the U.S. Navy awarded Vical a contract to support a phase I clinical trial of its vaccine against H1N1 influenza. “Our goal is to get that trial done by later this year,” Mr. Samant said.
In a virus challenge and protection study of Inovio's SynCon H1N1 vaccine, mice were injected with the H1N1 virus that caused the 1918 Spanish flu. Mice that received the H1N1 vaccine were completely protected from the virus, whereas all of the unvaccinated animals died within 1 week.
In 2010, the SynCon H5N1 vaccine will undergo human testing in healthy volunteers, followed by tests in combination with the SynCon H1N1 vaccine. Addition of H2N2 and other strains could soon follow.
Potential Pitfallr
“If we are correct, we can revolutionize how flu vaccines are made and delivered,” Dr. Kim said.
One potential pitfall of the DNA vaccine technology is the impending backlash from vaccine naysayers, cautioned Dr. Schaffner.
“We have a hardcore group of vaccine skeptics,” he said. “This is a group of people who look askance at vaccines, are dubious about their benefits, and are concerned about how they're manufactured and what's in them. Any innovation, whether it is the addition of an adjuvant, or a new technology such as this, will come to their attention and draw some of their skepticism and opposition. We have to brace for this.”
Dr. Schaffner disclosed that he has been a consultant for various vaccine manufacturers. He also is a member of a data safety committee for Merck for experimental vaccines.
'DNA vaccines can never replicate. They do not infect; they do not cause disease, ever.'
Source DR. KIM