Inovio Consensus DNA Vaccine Approach Demonstrates 100% Protection
Against Unmatched Flu Virus Strains Currently in Circulation
Inovio Biomedical Corporation (NYSE Amex: INO), a leader in DNA vaccine
design, development and delivery, announced today that the company's
SynCon™ H1N1 influenza DNA vaccines achieved protection against current
circulating swine origin influenza A/H1N1 viruses in animal studies.
The company had previously reported interim data from an ongoing study
in a pig model in which the SynCon™ based H1N1 vaccines achieved
hemagglutination inhibition (HI) titers above the protection threshold
in 100% of the vaccinated animals against the swine influenza virus
(A/Iowa/35233/1999). In a continuation of this study, Inovio
investigators tested the immune sera for responses against a virus
isolated from the current circulating strain of swine origin influenza
A/H1N1 (Swine A/Mexico/InDRE4487/2009). All the animals immunized with
the SynCon™ H1N1 vaccine developed HI titers exceeding the 1:40 level
commonly associated with protective immunity.
In a second study, the investigators immunized mice with the NP and m2E
components of the vaccine and challenged these animals with a second
related strain also isolated from the current circulating influenza
A/H1N1 (A/Canada/AB/RV1532/2009). While all mice showed effects of virus
challenge as judged by significant weight loss, the vaccinated mice
recovered from virus infection-induced morbidity significantly faster
compared to the non-immunized control animals.
In a previous study, the Inovio team demonstrated that mice immunized
with Inovio’s SynCon™ H1N1 DNA vaccine provided 100% protection in a
lethal challenge study against an unmatched H1N1 virus that caused the
1918 Spanish flu, which killed over 40 million people worldwide.
The challenge of current seasonal influenza vaccines is they are not
effective against new strains that emerge, like the present swine origin
influenza A/H1N1. The CDC reported low human prevaccination response
rates and cross-reactivity to swine origin influenza
(A/California/04/2009), suggesting that current H1N1 seasonal flu
vaccines were likely to be ineffective against the new 2009 A/H1N1
strains. Similarly, the USDA recently reported there was limited
cross-reactivity against the new 2009 A/H1N1 virus in pig herds
vaccinated with existing swine influenza vaccines.
Dr. J. Joseph Kim, Inovio’s CEO, said, “The latest data further
underscores the potential of the SynCon™ technology to create vaccines
capable of protecting against emerging pandemic influenza viruses.