SynCon® vaccines: designed to provide powerful immune responses

Inovio’s synthetic vaccine technology is designed to build on the great legacy of conventional vaccines – and overcome their boundaries - by not only preventing but treating diseases; providing universal protection against unmatched, rapidly mutating viruses; and breaking tolerance against cancers. Key features of our SynCon® technology include:

  • Design and selection of appropriate antigen targets for a particular disease. These include targets associated with the induction of antibody or T-cell or both immune responses observed during natural infection.
  • SynCon® vaccines use a DNA fragment with instructions that enable cells in the body to produce ONLY the targeted antigen relating to a pathogen or cancer. The fragment cannot replicate and is not able to cause the disease.
  • Rather than being constrained by the paradigm of matching a preventive or therapeutic vaccine to a single pathogen strain, our SynCon® vaccines are based on genetic code for a specific antigen from multiple strains of the target pathogen. Thus, while the SynCon® antigens may not be perfectly (100%) matched to the pathogenic strains, they are designed to protect against multiple existing strains as well as changing strains of a virus. Extensive preclinical data has validated their ability to protect against many strains of a disease; initial human data for our influenza vaccine has also provided evidence of this capability.


With respect to cancers, preclinical data has shown that these “unmatched” gene sequences aid the immune system’s recognition of “self-made” cells that are cancerous. Whereas normally it might tolerate these cells made in the body, antigens produced by SynCon® therapeutic vaccines are able to induce strong immune responses against the cancer cells.

  • SynCon® vaccines can produce strong T-cell responses (both CD4+ and CD8+): T-cell immune responses are considered vital to fighting cancerous cells and chronic infections. While live virus vaccines are able to generate T-cells, this approach is not viable for many diseases, such as HIV. Other “conventional” vaccine technologies (such as recombinant proteins, virus-like particles, subunit vaccines, and peptides) can at best produce only weak T-cell responses. Experimental approaches such as viral vectors have achieved strong T-cell responses, but have limiting factors such as their inability to boost with repeated vaccination due to immune responses to the viral vector itself (which can be based on a virus, such as a cold virus, to which we have been previously exposed).

    However, Inovio’s SynCon® vaccines have, in human studies for cervical dysplasia and HIV, generated best-in-class T-cell responses that exceed all these approaches. What is particularly exciting is that these responses include strong CD8+ T-cell responses which are able to kill targeted infected cells.  In a recent human study, Inovio’s vaccine for cervical dysplasia demonstrated for the first time that a DNA-based therapeutic vaccine can produce immune responses with a killing effect on target cells and potentially reverse disease progression to cervical cancer.

  • Inovio’s synthetic DNA vaccines can be designed in weeks instead of months or years. They are manufactured by a fast and efficient fermentation process. They have a better stability profile at room temperature compared to conventional vaccines and may not require a cold-chain for storage and transport. These important advantages yield more timely vaccine development and can improve accessibility in nations with less developed infrastructure.
  • The novel SynCon® genetic sequences, which do not exist in nature, are patentable.


The elegance of Inovio’s SynCon® vaccines is that we are not creating an immunogen that would then be placed into the body to induce a desired immune response. Instead, we create a fragment of DNA to produce one or more targeted antigens and place that DNA into cells of the body (with the assistance of our proprietary electroporation systems) where it does nothing other than give instructions to the cells to produce the desired antigen. This approach results in the body creating an immunogen capable of inducing strong, multi-faceted immune responses similar to immune responses to actual pathogens. Human data to date has shown our approach has a positive safety profile.

We believe this approach, depicted in the illustration below, has the potential to address many cancers and infectious diseases.
 

Inovio SynCon® Vaccines: from Bug to Vaccination

Targeted antigen production (multi-antigen, if desired) in the body, induces preventive antibody and therapeutic T-cell immune responses.

SynCon design and delivery