Inovio Pharmaceuticals' Novel Gene Immunoadjuvant Significantly Improves DNA Vaccine Immune Responses in Non-Human Primates

Inovio Pharmaceuticals' Novel Gene Immunoadjuvant Significantly Improves DNA Vaccine Immune Responses in Non-Human Primates

BLUE BELL, Pa., Jun 29, 2010 (BUSINESS WIRE) -- Inovio Pharmaceuticals, Inc. (INO 1.03, +0.01, +0.98%) , a leader in the development of therapeutic and preventive vaccines against cancers and infectious diseases, announced today that the peer-reviewed journal Molecular Therapy has published a paper entitled "IL-28B/IFN-lambda3 Drives Granzyme B Loading and Significantly Increases CTL Killing Activity in Macaques."

The paper, co-authored by researchers from Inovio and collaborators from University of Pennsylvania School of Medicine, notes that co-delivery of Inovio's immunoadjuvant, a DNA plasmid encoding interleukin (IL)-28B, with an Inovio optimized SynCon(TM) DNA vaccine using its proprietary electroporation (EP) technology significantly enhanced antigen-specific killer T cell responses in rhesus monkeys.

Dr. J. Joseph Kim, Inovio's president and CEO, said: "Inovio's goal is to revolutionalize the way new vaccine blockbusters are developed utilizing our DNA vaccine development platform, comprised of our SynCon(TM) optimized DNA vaccine constructs, novel formulations, electroporation delivery systems, and DNA manufacturing processes. In addition, Inovio has been developing novel gene immunoadjuvants able to safely and efficiently improve immune responses generated by DNA vaccines. Inovio's IL-28B has demonstrated these characteristics in non-human primates, the closest animal model for humans in terms of testing vaccines' immunological effects. The gene immunoadjuvant program complements our existing technology and will further enhance our dominant position in the field of optimized DNA vaccines."

An adjuvant is a pharmacological or immunological agent that improves the effect of a vaccine while having few if any direct effects when administered alone. They are often included in vaccines to enhance immune responses and/or reduce the amount of vaccine required and keep the injected foreign material at a minimum. Conventional adjuvants are composed of chemicals like aluminum and lipids (fatty acids), which often are not naturally found in the body. In contrast, a gene immunoadjuvant is a DNA plasmid encoded with the genetic blueprint of an important, naturally occurring immune molecule such as IL-28B. When this DNA plasmid is co-delivered with a DNA vaccine, both the vaccine and, in this case, IL-28B proteins are produced by the same cell. The presence of an immunoadjuvant such as IL-28B may enhance the attraction of particularly important immune cells such as dendritic cells or killer T cells. Generation of CD8+ killer T cells are considered instrumental in clearing cancerous or infected cells from the body and imperative to achieving sufficient potency of new vaccines against cancers and chronic infectious diseases such as HIV and hepatitis C.

Inovio has already demonstrated superior advantages in the magnitude and breadth of killer T cell immune responses induced in non-human primates by one of its optimized SynCon(TM) DNA vaccines delivered using its proprietary electroporation technology, without the use of an immunoadjuvant. The study results, recently published in Molecular Therapy, compared Inovio's platform with Merck's adenovirus serotype 5 (Ad5) vaccine, considered to be the most immunogenic among viral vectors. Inovio has also reported from its phase I clinical study of a SynCon(TM) DNA vaccine against HPV/cervical cancer the achievement of T cell response levels thought sufficient to provide therapeutic benefit.

The purpose of the IL-28B study was to assess the incremental benefit of a gene immunoadjuvant added to a DNA-based vaccine. This was the first study of IL-28B in non-human primates. The study compared an antigen alone, antigen delivered in combination with an IL-12 immunoadjuvant, and antigen delivered in combination with IL-28B. The antigen/IL-28B combination achieved the most significant and long-lived responses in generating CD8+ T cells. The level of T cell immune enhancement was significantly greater than for IL-12, a previously tested potent immunoadjuvant. The potent T cell immunoadjuvanting effects of IL-28B were first identified in small animals by scientists at the University of Pennsylvania. The university filed patent applications covering its IL-28B product and its use as an immunoadjuvant, and licensed exclusive worldwide rights to these patents to Inovio. Inovio also has IL-15, RANTES, and other gene immunoadjuvants in its pipeline.

This study was funded in part by grants and contracts from the Division of AIDS, National Institute of Allergy and Infectious Diseases (NIAID) to Inovio and University of Pennsylvania. Inovio is further testing IL-28B as an immunoadjuvant in its efforts to develop a globally-targeted HIV vaccine candidate, PENNVAX(TM)-GP, via a multi-year $23.5 million NIAID HIV Vaccine Design and Development (HVDDT) contract and in a novel malaria vaccine development program funded by the Malaria Vaccine Initiative/PATH.

About Inovio Pharmaceuticals, Inc.

Inovio is developing a new generation of vaccines, called DNA vaccines, to treat and prevent cancers and infectious diseases. The company's SynCon(TM) "universal" vaccines are designed to provide broad cross-strain protection against known as well as newly emergent strains of pathogens such as influenza. When delivered with Inovio's proprietary electroporation delivery devices the vaccines have been shown to be safe and to generate significant immune responses. Inovio's clinical programs include HPV/cervical cancer (therapeutic), avian flu, and HIV vaccines (both preventive and therapeutic). Inovio is developing its universal influenza vaccines in collaboration with scientists from the University of Pennsylvania and National Microbiology Laboratory of the Public Health Agency of Canada. Other partners and collaborators include Merck, ChronTech, University of Southampton, National Cancer Institute, HIV Vaccines Trial Network, and Malaria Vaccine Initiative/PATH. More information is available at

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 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 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, our ability to successfully integrate Inovio and VGX Pharmaceuticals, 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, 2009, our Form 10-Q for the three months ended March 31, 2010, 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.

SOURCE: Inovio Pharmaceuticals, Inc.