CVC is utilising a well-researched technology originally developed at Massey University in Palmerston North, New Zealand. The technology enables the efficient production of tiny biobeads that are coated in whatever protein or polypeptide one chooses. In our case, we will coat these biobeads in proteins and polypeptides that occur in the SARS-Cov-2 virus. The biobeads and protein coating are simultaneously manufactured inside bacteria which is a very efficient method of production.

Round biobeads that have formed inside a bacterium

The system has the capability to attach most proteins to the surface of the biobeads. In the case of our vaccine, we intend to place two elements on the surface of the biobeads. One will be from part of the virus protein that attaches to human cells (technically, the receptor binding domain of the S or spike protein). It is expected that this will induce antibodies to the virus, including neutralising antibodies. The other will be a string of specific parts of various virus proteins (T cell epitopes) that is expected to induce a cytotoxic immune response. The two will be manufactured in separate batches and then combined.

The main aspects of the biobeads technology are:

• the bead-protein complex (the biobead) is produced in vivo in bacteria.
• The bead itself is a polyester and is biodegradable and biologically inert.
• The biobeads are grown at high cell density which keeps production costs down.
• Proteins are displayed at high density on the surface of biobeads.
• The system is versatile. Proteins with many different functionalities can be displayed on the biobeads.
• Functionalities of proteins displayed on biobeads are well maintained.
• The biobeads have been shown to be of use in developing other vaccines including hepatitis C, tuberculosis, meningococcal meningitis and pneumococcal diseases (all tested in animals but not humans).