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Inovio Biomedical Cervical Cancer Therapeutic Vaccine Generates Dose-Related Immune Response in Clinical Trial
[February 08, 2010]

Inovio Biomedical Cervical Cancer Therapeutic Vaccine Generates Dose-Related Immune Response in Clinical Trial


SAN DIEGO --(Business Wire)-- Inovio Biomedical Corporation (NYSE Amex: INO), a leader in DNA vaccine design, development and delivery, announced today additional interim safety and immunogenicity data from its therapeutic cervical cancer vaccine (VGX-3100) trial. VGX-3100 is a DNA vaccine targeting the E6 and E7 proteins of human papillomavirus (HPV) types 16 and 18 and is delivered via in vivo electroporation. Similar to previously reported data from the initial lowest dose cohort of this phase I trial, the vaccine was found to be generally safe and well tolerated. While previously reported data showed significant cellular and humoral immune responses, data from this second, intermediate dose group highlighted a significantly increased and dose-related immune response specific to the antigens targeted by the vaccine.



"We are extremely pleased with the safety and tolerability profile of VGX-3100. Furthermore, analyses of the vaccinated subjects from the first two cohorts indicate that this vaccine is highly immunogenic, generating antigen-specific T-cell and antibody responses that are amongst the highest reported from any previous human studies of DNA vaccines," stated Dr. J. Joseph Kim, President and CEO.

"While recent HPV preventive vaccines have been successful in protecting against infections that may lead to cervical cancer, Inovio's therapeutic vaccine targets the millions of women already infected with HPV and is intended to treat pre-cancerous cells and cervical cancer caused by this virus. Current vaccines do not serve this group of women," Dr. Kim added.


This dose escalation study was designed to test the safety and immunogenicity of VGX-3100 in women with a previous history of cervical intraepithelial neoplasia (CIN) 2/3, a precursor lesion prior to the development of cancer. The trial is enrolling patients in three cohorts of six subjects each with DNA vaccine doses at 0.6 mg (0.3 mg each of two DNA plasmids), 2.0 mg, and 6.0 mg. The immunization regimen consists of each subject receiving the respective dose at day 0, month 1 and month 3. The vaccine is delivered using Inovio's proprietary CELLECTRA® intramuscular electroporation delivery device.

All six patients in the second, intermediate dose cohort have been enrolled; samples from the first four patients have been evaluated for immune responses. As with the first cohort, the vaccination procedures were well-tolerated by the subjects in the second cohort. In general, reported adverse events and injection site reactions were mild to moderate and required no treatment.

The preliminary immunological analysis of blood samples collected before and after vaccination indicated the induction of antigen-specific immune responses against the target proteins produced by the vaccine. Antigen-specific cytotoxic T-lymphocyte (CTL) responses were observed against all four antigens (E6 and E7 proteins for HPV types 16 and 18). In this cohort, 2 of 4 vaccinated subjects (50%) developed significant CTL responses, with average responses of 532 SFU per million cells after three immunizations. This was a 71% increase in CTL responses compared to the lowest dose cohort, which also yielded 50% responders (3 out of 6) and average CTL responses of 311 SFU per million cells. Generation of tumor-specific T cell responses is believed to be an important characteristic of a cancer therapeutic vaccine.

Inovio also tested the samples for antibody responses against the target antigens and observed strong antibody responses in 4 of 4 subjects (100%). Antibodies were generated against all four antigens, as tested by the enzyme-linked immunosorbent assay (ELISA). The current results were an improvement over the results from the first cohort, in which 5 of 6 vaccinated subjects (83%) developed strong antibody responses. The level of antibody responses in the current cohort was 5 - 10 fold higher than that observed in the lowest-dose cohort. The average antibody titer to both HPV E7 proteins in the current cohort was greater than 1:50,000.

Specific antibody responses to tumor antigens can function as an important surrogate potency marker for determining the immunogenicity of a vaccine, i.e. the ability of a vaccine to induce an immune response. Furthermore, Inovio believes these results underscore the potential usefulness of its DNA vaccine platform against infectious disease targets, where generation of antibodies has been shown to be protective.

Inovio expects full enrollment of all three cohorts in the first half of 2010 and complete immunogenicity and safety data to be reported in Q4 2010.

About HPV, Cervical Cancer and Inovio's Therapeutic DNA Vaccine Human papillomavirus (HPV) is the causative agent responsible for most cases of cervical cancer. HPV types 16 and 18 are responsible for about 70% of cervical cancer incidences. Globally, over 253,500 women die of cervical cancer each year.

Preventive vaccines such as GARDASIL® and CERVARIX® are playing a role in limiting infection of HPV. However, the huge number of patients already infected with HPV cannot be addressed by preventive vaccines and there is no viable therapeutic vaccine or drug to fight HPV and cervical cancer.

Inovio's VGX-3100 is designed to express the E6 and E7 genes common to HPV types 16 and 18 and that are present in both pre-cancerous and cancerous cells transformed by these HPV types, with the goal of stimulating the body's immune system to mount a T-cell response strong enough to cause the rejection of these unwanted cells from the body.

About Inovio Biomedical Corporation Inovio Biomedical is focused on the design, development, and delivery of a new generation of vaccines, called DNA vaccines, to prevent and treat cancers and infectious diseases. The company's SynCon™ technology enables the design of "universal" vaccines capable of protecting against multiple - including newly emergent, unknown - strains of pathogens such as influenza. Inovio's proprietary electroporation-based DNA vaccine delivery technology has been shown by initial human data to safely and significantly increase gene expression and immune responses. Inovio's clinical programs include HPV/cervical cancer (therapeutic) and HIV vaccines. An IND has been filed for an avian influenza vaccine. Inovio is developing its universal and avian influenza vaccines in collaboration with scientists from the University of Pennsylvania, the National Microbiology Laboratory of the Public Health Agency of Canada, and the NIH's Vaccine Research Center. Other partners and collaborators include Merck, Tripep, University of Southampton, National Cancer Institute, and HIV Vaccines Trial Network. More information is available at www.inovio.com.

This press release contains, in addition to historical information, forward-looking statements. Such statements are based on management's current estimates and expectations and are subject to a number of uncertainties and risks that could cause actual results to differ materially from those described in the forward-looking statements. Inovio is providing this information as of the date of this press release, and expressly disclaims any duty to update information contained in this press release.

Forward-looking statements in this press release include, without limitation, express and implied statements relating to Inovio's business, plans to develop electroporation-based drug and gene delivery technologies and DNA vaccines and pre-clinical and clinical studies. Actual events or results may differ from the expectations set forth herein as a result of a number of risks, uncertainties and other factors, including but not limited to: Inovio has a history of losses; all of Inovio's potential human products are in research and development phases; no revenues have been generated from the sale of any such products, nor are any such revenues expected for at least the next several years; Inovio's product candidates will require significant additional research and development efforts, including extensive preclinical and clinical testing; uncertainties inherent in clinical trials and product development programs, including but not limited to the fact that pre-clinical and clinical results 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, that results from an animal study may not be indicative of results achievable in human studies, that clinical testing is expensive and can take many years to complete, that the outcome of any clinical trial is uncertain and failure can occur at any time during the clinical trial process, and that Inovio's electroporation technology and DNA vaccines may fail to show the desired safety and efficacy traits in clinical trials; all product candidates that Inovio advances to clinical testing will require regulatory approval prior to commercial use, and will require significant costs for commercialization; the availability of funding; the ability to manufacture vaccine candidates; the availability or potential availability of alternative therapies or treatments for the conditions targeted by Inovio or its collaborators, including alternatives that may be more efficacious or cost-effective than any therapy or treatment that Inovio and its collaborators hope to develop; whether Inovio's proprietary rights are enforceable or defensible or infringe or allegedly infringe on rights of others or can withstand claims of invalidity; and the impact of government healthcare proposals. Readers are also referred to Inovio's Annual Report on Form 10-K for the year ended December 31, 2008 and its Quarterly Report on Form 10-Q for the quarter ended September 30, 2009 filed with the Securities and Exchange Commission which identify important risk factors that could cause actual results to differ from those contained in the forward-looking statements.

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