Preclinical Efficacy of Inovio Pharmaceuticals' Chikungunya DNA Vaccine Featured in PLoS Neglected Tropical Diseases
DNA vaccine induces protective antibody and T-cell immune responses in non-human primates against Chikungunya virus
BLUE BELL, Pa.--(BUSINESS WIRE)--Jan 12, 2011 - Inovio Pharmaceuticals, Inc. (NYSE Amex: INO), a leader in the development of novel therapeutic and preventive vaccines against cancers and infectious diseases, announced today the publication of a scientific paper highlighting positive results from Inovio's multi-antigen Chikungunya virus (CHIKV) DNA vaccine in PLoS Neglected Tropical Diseases. The paper, entitled “A DNA vaccine against Chikungunya virus is protective in mice and induces neutralizing antibodies in mice and nonhuman primates,” authored by Inovio scientists and collaborators, describes the ability of the vaccine to induce robust antibody and T-cell immune responses and provide 100% protection of mice against a challenge with this tropical infectious disease. Additionally, vaccine studies in rhesus macaques demonstrated generation of strong neutralizing antibody responses which mimicked those observed in CHIKV-infected human patients who subsequently recovered from this disease. These results demonstrate the ability of Inovio's DNA vaccine to provide protection and protective immune responses in two different preclinical models.
CHIKV is an emerging mosquito-borne virus indigenous to tropical Africa and Asia. Acute illness is characterized by fever, arthralgia (pain in a joint), conjunctivitis (eye inflammation), rash, and sometimes arthritis. Relatively little is known about the antigenic targets for immunity and no licensed vaccines or therapeutics are currently available. Considering the potential for pandemic spread, understanding the development of immunity is paramount to the development of effective vaccines against CHIKV.
In this study, the research team isolated CHIKV from an acutely infected human patient and used this newly isolated virus to develop a virus neutralization assay and a challenge stock. The CHIKV challenge stock was used to establish a mouse infection model and study disease development. The candidate CHIKV vaccine developed by the researchers and tested in the mouse and macaque models is a SynCon™ synthetic DNA vaccine consisting of a single consensus envelope construct that expresses all three of the CHIKV envelope glycoproteins (E3+E2+E1). The vaccine is delivered by in vivo electroporation.
Dr. J. Joseph Kim, president and CEO of Inovio Pharmaceuticals, said, “Inovio has been researching and developing novel vaccine candidates for several emerging infectious diseases with pandemic potential such as Chikungunya virus utilizing our potent DNA vaccine development platform. These published data suggest a protective role for antibodies against Chikungunya, a re-emerging health threat in both developing and developed countries, and support further development of Inovio's DNA vaccine for this disease.”
About Chikungunya Virus
CHIKV has been identified as the virus responsible for major epidemics in both Africa and Southeast Asia and continues to be a re-emerging virus of great interest to public health. While the Aedes aegypti mosquito is its primary vector, recent evidence suggests that other carriers can transmit CHIKV. Significantly, exposed travelers returning from the affected areas to Europe, the US, Canada, Hong Kong, and numerous other countries have carried the virus into these new territories.
Upon infection, Chikungunya fever tends to present itself in two phases. The first stage is acute, with symptoms including abrupt onset of fever, joint pain and, in some cases, rash. It causes intense joint and muscular pain that makes movement very difficult. The second stage, experienced by most but not all, is persistent, causing disabling polyarthritis. Ninety-five percent (95%) of infected adults are symptomatic after infection; of these most become disabled for weeks to months as a result of decreased dexterity, loss of mobility, and delayed reaction.
Several vaccines are in development against CHIKV, such as a formalin-inactivated vaccine, a virus-like particle vaccine and a live attenuated vaccine. None have advanced to clinical development and therefore illustrate an important area of need. While the threat of a pandemic continues to engage the public's attention, the peculiar problems associated with the more immediate and very real seasonal epidemics are also worthy of consideration. Specifically, there are limited viral strains that have been characterized and available for laboratory study as well as knowledge of immune responses induced to the virus.
About Inovio Pharmaceuticals, Inc.
Inovio is developing a new generation of vaccines, called DNA vaccines, to treat and prevent cancers and infectious diseases. These SynCon™ vaccines are designed to provide broad cross-strain protection against known as well as newly emergent strains of pathogens such as influenza. These vaccines, in combination with Inovio's proprietary electroporation delivery devices, have been shown to be safe and generate significant immune responses. Inovio's clinical programs include HPV-caused cervical dysplasia and cancer (therapeutic), avian flu (preventive), and HIV vaccines (both preventive and therapeutic). Inovio is developing DNA vaccines in collaboration with scientists from the University of Pennsylvania. Other partners and collaborators include Merck, National Cancer Institute, U.S. Military HIV Research Program, NIH, HIV Vaccines Trial Network, National Microbiology Laboratory of the Public Health Agency of Canada, 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 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, 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 nine months ended September 30, 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.
Posted: January 2011