Inovio Biomedical Universal DNA Vaccine For Chikungunya Virus Demonstrates Protective Antibody Responses In Monkey Model

Main Category: Infectious Diseases / Bacteria / Viruses
Also Included In: Immune System / Vaccines
Article Date: 20 Nov 2009 - 1:00 PDT

email to a friend   printer friendly   opinions  

Inovio Biomedical Corporation (NYSE Amex: INO), a leader in DNA vaccine design, development and delivery, announced that the company's SynCon™ Chikungunya virus DNA vaccine induced protective neutralizing antibody responses in a preclinical non-human primate model. Dr. David B. Weiner, Professor, University of Pennsylvania and Chairman, Inovio Scientific Advisory Board, discussed the data at the VACCINES EUROPE conference in Brussels, Belgium, in a presentation entitled, "Engineering DNA vaccine potency in vivo results in improved immunity: improving vaccine immunogenicity and efficacy."

Chikungunya virus (CHIKV) is an emerging mosquito-borne alpha-virus native to tropical Africa and Asia. Attack rates (the cumulative incidence of infection in a group of people observed over a period of time) of up to 45% have been reported (WHO). While CHIKV is rarely life-threatening, it causes severe human morbidity. Acute illness is characterized by severe fever and debilitating joint pain, and recovery can take a year or longer. Recent evidence suggests that CHIKV can be transmitted by several types of mosquitos commonly found in developed countries, raising concerns about the spread of this pathogen outside its natural endemic areas to new regions including Europe and the United States.

There are no commercialized vaccines or therapeutics against CHIKV. In fact, very little is known about the basis for CHIKV-based disease, including the mechanism of immune-based viral clearance and the causes of clinical symptoms. Considering the potential for global spread of CHIKV, understanding the virus's pathogenic mechanism and developing effective treatment options are paramount.

Inovio scientists used its proprietary SynCon™ approach to develop a universal CHIKV DNA vaccine. The candidate vaccine is delivered as a single DNA plasmid construct containing consensus sequences of key surface antigens. The universal CHIKV vaccine was designed by aligning numerous primary sequences of key surface antigens and choosing the most common amino acid or base pair at each site. In previous mice studies, Inovio scientists found that this universal vaccine induced protective neutralizing antibody responses and demonstrated protection from both death and illness in a challenge-protection model (published in Vaccine (2008) 26:5128).

In the present study, the vaccine efficacy was further tested in a monkey model, the closest animal model to humans. In this model, 100% of the vaccinated animals developed protective neutralizing antibody responses against native CHIKV, demonstrating the utility and effectiveness of this vaccine in an advanced preclinical model.

Dr. J. Joseph Kim, Inovio's President and CEO, said, "Chikungunya virus represents a clear unmet need because it is endemic in many regions of the world and has epidemic potential. With our recent clinical trial data showing our vaccine platform's ability to induce strong antibody responses in vaccinated subjects, we hope to be able to translate these preclinical successes presented in the current study into clinical progress in the near future."

Inovio's novel SynCon™ technology enables the company to design DNA-based vaccines with the potential to protect against known and unknown strains of pathogens. Inovio's design process synthetically defines antigens and gene sequences common across different viral sub-types or taxonomic groups (families) of diseases such as HIV, HCV, human papillomavirus (HPV), and influenza.

Inovio recently announced interim data from a Phase I therapeutic HPV/cervical cancer vaccine trial showing significant and robust T-cell and antibody immune responses, results that highlight the potential broad utility of its DNA vaccine technology platform and applicability to many diseases, such as Chikungunya virus.

Source
Inovio Biomedical Corporation

• Additional
• References
• Citations