Inovio's Universal H7N9 DNA Vaccine Generates First Protective Antibody Responses Against Virulent H7N9 Virus in 100% of Vaccinated Animals

BLUE BELL, Pa., June 14, 2013 /PRNewswire/ -- Inovio Pharmaceuticals, Inc. (NYSE MKT: INO) announced today that in a preclinical study of its influenza DNA vaccine against the newly emergent, virulent H7N9 flu virus it achieved immune response levels exceeding what are considered protective levels in other common influenza subtypes. Interim results from a study in mice in a collaboration with researchers from the University of Pennsylvania and Canada's National Microbiology Laboratory in Winnipeg demonstrated that Inovio's H7N9 influenza DNA vaccine achieved greater than 1:40 hemagglutination inhibition (HAI) in 100% of tested animals (n=10), with a geometric mean HAI titer of 1:130 against the A/Anhui/1/13 strain of H7N9 virus. HAI titers at or above 1:40 are considered to denote protection against the influenza virus in humans. These mice received just two vaccinations three weeks apart and the samples tested were from week 5.

Since the first-ever infection of a human with this new influenza subtype in early 2013, the very rapid spread of H7N9 reached a total of 131 confirmed human infections in Asia, with 39 deaths. Experts remain fearful of the possibility of the virus mutating into a form easily transmissible between humans, with the potential to trigger a pandemic. Laboratory tests showed that in some patients the H7N9 virus was resistant to treatment drugs, researchers in China wrote in the medical journal The Lancet last month, adding that their findings were "concerning." 

Dr. J. Joseph Kim, Inovio's President and CEO said, "These results show the advantages of Inovio's DNA vaccines versus traditional approaches in two significant ways: how our DNA vaccines can mount a robust defense against emerging potent viral threats with pandemic potential; and, how rapidly we can create a DNA vaccine construct to address a new global threat." 

In the preclinical study Inovio researchers constructed a consensus DNA vaccine targeting the HA influenza antigen from sequences collected from several infected H7N9 patients to be broadly protective against all H7N9 viruses. The vaccine was designed, optimized, and manufactured within two weeks, and mice were immunized intramuscularly with two doses followed by electroporation three weeks apart. In an interim analysis, researchers tested sera from the animals against an unmatched H7N9 influenza strain, A/Anhui/1/13. The researchers observed levels of HAI titers, or functional antibodies, that predict protection against the H7N9 virus as well as robust levels of binding antibodies which can block virus entry into host cells as well as inhibit other viral functions.

Generating these very strong immune responses against an unmatched influenza strain adds further to the growing data set indicating the universal protective capability that Inovio's SynCon® DNA vaccines are able to achieve within targeted subtypes. While this study demonstrates that Inovio can respond to an urgent need to address a new subtype of influenza, it also provides further validation of its approach to address the more important need of providing truly preemptive and broad long-term protection against the constant strain mutations that occur within influenza subtypes. The ideal outcome would be to achieve a universal influenza vaccine capable of broad protection against existing and newly emergent unmatched strains across subtypes known to threaten humans.

Using our synthetic consensus design approach, we have created DNA "constructs" for key virus clades (branches) within the Type A subtypes H1N1, H2N2, H3N2, and H5N1 as well as Type B, and target multiple influenza antigens associated with influenza, including the most frequently changing antigen, HA. We can mix and match these individual DNA plasmid constructs as desired to create vaccine candidates. Inovio has previously reported human data indicating protective immune responses against the subtypes H1N1 and H5N1.

About Inovio Pharmaceuticals, Inc.

Inovio is revolutionizing vaccines to prevent and treat today's cancers and challenging infectious diseases. Its SynCon® vaccines are designed to provide universal protection against known as well as new unmatched strains of pathogens such as influenza. These synthetic vaccines, in combination with Inovio's proprietary electroporation delivery, have been shown in humans to generate best-in-class immune responses with a favorable safety profile. Inovio's clinical programs include phase II studies for cervical dysplasia, leukemia and hepatitis C virus and phase I studies for influenza and HIV. Partners and collaborators include the University of Pennsylvania, Merck, ChronTech, National Cancer Institute, U.S. Military HIV Research Program, NIH, HIV Vaccines Trial Network, University of Southampton, US Dept. of Homeland Security, University of Manitoba and PATH Malaria Vaccine Initiative. More information is available at www.inovio.com.

This press release contains certain forward-looking statements relating to our business, including our plans to develop electroporation-based drug and gene delivery technologies and DNA vaccines and our capital resources. Actual events or results may differ from the expectations set forth herein as a result of a number of factors, including uncertainties inherent in pre-clinical studies, clinical trials and product development programs (including, but not limited to, the fact that pre-clinical and clinical results referenced in this release may not be indicative of results achievable in other trials or for other indications, that the studies or trials may not be successful or achieve the results desired, that pre-clinical studies and clinical trials may not commence or be completed in the time periods anticipated, that results from one study may not necessarily be reflected or supported by the results of other similar studies and that results from an animal study may not be indicative of results achievable in human studies), the availability of funding to support continuing research and studies in an effort to prove safety and efficacy of electroporation technology as a delivery mechanism or develop viable DNA vaccines, the adequacy of our capital resources, the availability or potential availability of alternative therapies or treatments for the conditions targeted by the company or its collaborators, including alternatives that may be more efficacious or cost-effective than any therapy or treatment that the company and its collaborators hope to develop, evaluation of potential opportunities, issues involving product liability, issues involving patents and whether they or licenses to them will provide the company with meaningful protection from others using the covered technologies, whether such proprietary rights are enforceable or defensible or infringe or allegedly infringe on rights of others or can withstand claims of invalidity and whether the company can finance or devote other significant resources that may be necessary to prosecute, protect or defend them, the level of corporate expenditures, assessments of the company's technology by potential corporate or other partners or collaborators, capital market conditions, the impact of government healthcare proposals and other factors set forth in our Annual Report on Form 10-K for the year ended December 31, 2012, our Form 10-Q for the quarter ended March 31, 2013, and other regulatory filings from time to time. There can be no assurance that any product in Inovio's pipeline will be successfully developed or manufactured, that final results of clinical studies will be supportive of regulatory approvals required to market licensed products, or that any of the forward-looking information provided herein will be proven accurate.

CONTACTS: 
Investors: Bernie Hertel, Inovio Pharmaceuticals, 858-410-3101, [email protected]
Media: Jeff Richardson, Inovio Pharmaceuticals, 267-440-4211, [email protected]