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The goal of vaccination is to induce an immune response that enables the body’s own defenses, the immune system, to fend off attack from specific pathogens. The main obstacle to vaccination for certain viruses such as HIV, HCV and influenzavirus are:

i) Extreme antigenic variation due to rapid mutation: constant evolution of viral strains rendering traditional vaccine approaches effective only to a specific subset of strains. For influenzavirus, new vaccines are generated each year based upon knowledge of the most recently circulating strains.

ii) Multiple types and subtypes: Certain viruses exist as multiple types such as HPV. Certain types are associated with pathogenic effects such as HPV 16 and 18 that are associated primarily with cervical cancer.

Bionor Pharma’s approach using modified peptides (small protein fragments) represents a solution to these obstacles. Peptides can be used to trigger either a cell-mediated immune response or an antibody response.

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Peptide selection: Through the analysis of multiple strains of a virus, certain areas with low mutation frequency can be identified. Due to the constant nature one can infer that they:

i) represent critical functions of the virus and

ii) that they will remain constant across new strains - thus overcoming the obstacles of extreme antigenic variation and rapid mutations.   

Peptide design:  To enhance the ability of the peptide to stimulate an effective immune response, the natural sequences can be modified whilst still retaining cross reactivity to the original antigen. The technology for selecting and modifying peptides is based on proprietary in-house developed know-how.

Peptide delivery: The peptides are delivered to dendritic cells (immune cells) through intradermal injection in combination with an adjuvant. Dendritic cells are targeted because they are the most potent antigen presenting cells and they have the capacity to present peptides to the immune system to induce both cell-mediated as well as humoral responses through the process of cross presentation.

Benefits of using peptides: Peptides do not contain genetic material, cause few transient minor side effects, and are safe to administer to people of all ages. They allow for unlimited boosting and cost-effective large-scale production.