Inovio Pharmaceutical's DNA Vaccine for the Deadly MERS Virus Induces Robust Immune Response in Preclinical Trial

No vaccine exists for the MERS virus that has killed 42% of those infected

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Nov 20, 2013, 03:05 ET

BLUE BELL, Pa., Nov. 20, 2013 /PRNewswire/ -- Inovio Pharmaceuticals, Inc. (NYSE MKT: INO) announced today that preclinical testing of a DNA synthetic vaccine for the virulent Middle East Respiratory Syndrome coronavirus (MERS) induced robust and durable immune responses, demonstrating the potential for a SynCon^® DNA vaccine to prevent and treat this deadly virus.

Since 2012, when the virus was first identified, 153 cases from nine Middle Eastern countries have been reported and, alarmingly, 42% of these cases have been fatal. MERS is similar to the SARS virus which infected 8,000 people several years ago. MERS differs from SARS in that it appears to be less contagious, but MERS is almost five times as fatal as SARS, which killed 10% of those infected. There is no vaccine or effective treatment for MERS.

In this study, DNA vaccine constructs targeting multiple MERS antigens were generated using Inovio's SynCon® vaccine platform. These SynCon constructs were administered via Inovio's CELLECTRA® electroporation-based delivery technology. The vaccine constructs were observed to induce strong neutralizing antibodies and broad CD8+ T cells in mice. These findings are vital given the importance of neutralizing antibodies in preventing infection and the role T cells play in clearing infection by killing cells that harbor the virus.

Dr. J. Joseph Kim, Inovio's President and CEO, said, "Our SynCon^® platform has again generated a synthetic vaccine candidate that shows promise for providing a treatment where there is none. With human data showing the powerful killing effect of T cells generated by our vaccine for HIV and our therapy for HPV-associated cervical dysplasia and various cancers, we look forward to providing Inovio's answer to MERS, a deadly infectious disease that has unknown pandemic potential. What's even more impressive about our candidate vaccine is that it is designed with the goal to universally protect against multiple strains of MERS, which has been shown to have diverse genetic variants. With appropriate external funding, this product could become an effective shield against this deadly virus."

To begin the study, a consensus MERS "spike" protein vaccine construct was created based on multiple strains of the MERS virus. Inovio's MERS DNA vaccine was immunogenic in mice and seroconversion, or the development of detectable specific antibodies in the blood as a result of immunization, was observed in all animals. Furthermore, the antibodies generated by the vaccine in 100% of mice (20 of 20) were able to neutralize or completely block actual infection of MERS virus in the cells, demonstrating the protective potential of this vaccine. In contrast, none of the unvaccinated mice in the control group (10) generated neutralizing antibodies.

Researchers also observed that vaccination was highly T-cell immunogenic, generating robust and broad T cell responses as extensively analyzed by the standardized T cell ELISPOT assay. The vaccine produced robust CD8+ and CD4+ T cell responses against multiple epitopes of the MERS spike protein. This increased diversity and magnitude of cellular responses may be critical for effectively mitigating MERS infection.

About MERS

Middle East Respiratory Syndrome (MERS) is a viral respiratory illness first reported in Saudi Arabia in 2012. MERS appears to have been transmitted from an "animal reservoir" to humans but human to human transmission has also been confirmed. The virus has not been shown to spread in a sustained way in communities, but the situation is still evolving. Like SARS, which infected 8,000 people and was fatal in nearly 10% of cases, MERS appears to cause a severe lung infection. MERS differs in that it also causes rapid kidney failure and its extremely high death rate has caused serious concern among global health officials.

The World Health Organization has confirmed 153 cases of MERS in nine countries; 64, or 42%, of these cases have been fatal. All cases have been directly or indirectly linked through travel to or residence in four countries: Saudi Arabia, Qatar, Jordan, and the United Arab Emirates. Experts are still struggling to understand MERS, for which there is no vaccine. No cases have been reported in the U.S., but as a precaution, the CDC has prepared diagnostic kits that have been distributed throughout the U.S.

About Inovio Pharmaceuticals, Inc.

Inovio is revolutionizing vaccines to prevent and treat today's cancers and challenging infectious diseases. Its SynCon® vaccines, in combination with its proprietary electroporation delivery, are generating best-in-class immune responses, with therapeutic T-cell responses exceeding other technologies in terms of magnitude, breadth, and response rate. Human data to date have shown a favorable safety profile. Inovio's lead vaccine, a therapeutic against HPV-caused pre-cancers and cancers, is in phase II. Other phase I and preclinical programs target prostate, breast, and lung cancers as well as HIV, influenza, malaria and hepatitis. Partners and collaborators include Roche, the University of Pennsylvania, Merck, NIH, HIV Vaccines Trial Network, National Cancer Institute, U.S. Military HIV Research Program, 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 September 30, 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]

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SOURCE Inovio Pharmaceuticals, Inc.