Human Vaccines journal publishes paper on Inovio's new DNA vaccine delivery technology

Inovio Pharmaceuticals, Inc., a leader in the development of therapeutic and preventive vaccines against cancers and infectious diseases, announced today that its new generation DNA vaccine delivery technology, which provides the powerful enabling capabilities of electroporation without contacting the skin, is highlighted in a paper published in the scientific journal Human Vaccines. While current Inovio electroporation devices have been shown to be safe and well-tolerated in multiple human studies, Inovio has been advancing research to achieve the most optimal device characteristics to facilitate mass vaccinations.

Dr. J. Joseph Kim, Inovio's president and CEO, said, "Inovio continues to raise the bar in terms of technological innovation that will further optimize electroporation-based delivery of DNA-based therapeutics and vaccines for patients of all ages. While still enabling levels of vaccine potency that we have observed with our existing electroporation devices, this new contactless delivery method is non-invasive and amenable to the design of devices that are low-cost, portable, and extremely easy to use."

Drug delivery into skin, or dermal tissue, is the most attractive method given that the skin is the largest, most accessible, and most easily monitored organ of the human body, and it is highly immunocompetent (able to recognize antigens and mount an immune response to them). The paper appearing in Human Vaccines, "Piezoelectric permeabilization of mammalian dermal tissue for in vivo DNA delivery leads to enhanced protein expression and increased immunogenicity," authored by Inovio scientists, describes an innovative electroporation method optimized for delivery into skin. This new method is based on piezoelectricity, which is the generation of an electric field or electric potential by certain materials in response to applied mechanical stress.

In the study, Inovio researchers investigated whether the electrical field strength generated by piezoelectricity alone could elicit gene transfer in the skin of an animal. Researchers injected a plasmid encoding GFP (a type of protein that generates fluorescence) into guinea pig skin and delivered electrical pulses using the contactless electroporation device. Three days following treatment, researchers observed robust protein expression on the skin of pulsed animals. Furthermore, superior immune responses were achieved when a DNA vaccine expressing an influenza antigen was delivered and pulsed using this novel device, in contrast to a lack of immune response when the antigen was injected but not pulsed.

Employing piezoelectricity in this new technology also provides other desirable benefits. Eliminating the insertion of needles used in the conventional electroporation process and reducing the electrical pulsing to nanoseconds makes this contactless device even more tolerable than current and emerging electroporation device designs. The sensation experienced is similar to the feeling of static electricity. In addition, the nature of piezoelectricity preempts the need for a battery or electrical power source, which would be beneficial for mass vaccinations in the field, particularly in developing countries.

Inovio's electroporation delivery devices use controlled, brief electrical pulses to create permeability in cell membranes, which can dramatically increase cellular uptake of a DNA vaccine and resulting gene expression (production of the antigen coded by the DNA vaccine). Data achieved in animal and human studies has indicated that electroporation based delivery enables potent immune responses, which are considered vital to tackling challenging infectious diseases and cancers.