Commercial manufacture of a novel dual hepatitis vaccine (Hepatacore)

This project is a further development of the tandem core® vaccine platform which is likely to have a wide utility in the generation of powerful new vaccines. This platform has a number of advantages including high immunogenicity, good stability and decreased cost of goods due to the fact that only a single protein is made. Previously, we had shown that tandem core was capable of expressing two vaccine targets simultaneously and could generate strong immune responses. However, this material was produced in bacteria and was subsequently found not to be of a quality suitable for human use. Hence, this project sought to re-engineer the construct for expression in yeast, which are more commonly used in vaccine production and have an excellent safety record.
The consortium used a combined hepatitis A and B vaccine as an exemplar and successfully transferred the system into a yeast vector. Although expression was easily achieved it was discovered that expression in yeast greatly increased the complexity of the purification process required to recover the protein. Hence, a robust purification method was developed which is suitable for all future tandem core constructs. This has now been successfully completed and the system is now ready for commercialisation in a variety of disease targets.