Vaccitech Technology

Viral vector vaccines are particularly good at treating some of the most recalcitrant human illnesses, which may be controlled by inducing the body to make T cell responses. The company’s proprietary chimpanzee adenovirus technology, followed in some programs by boosting with a heterologous vector such as Modified vaccinia Ankara (MVA), is used to generate both CD4+ and CD8+ T-cell responses and thereby generate lasting cell-mediated immunity. These responses are among the highest T cell-induced activity to have been shown in man.

The patented Vaccitech adenovirus vectors are known as chimpanzee adenovirus Oxford 1 and 2 (ChAdOx1 and ChAdOx2), and are in the group E simian adenovirus family, similar to the widely-studied chimpanzee adenovirus 63. These viruses have been engineered to be replication deficient, and can be manufactured in well-established HEK293 cell lines containing the adenoviral E1 gene. The viruses have high carrying capacity for the genes encoding cancer or pathogen proteins of interest. Both ChAdOx vectors have been moved into clinical studies, with hundreds of participants receiving the intramuscular ChAdOx1 in trials for MERS, tuberculosis, influenza and prostate cancer.

Adenoviral vectors represent exceptional priming vaccines, but are difficult to reuse in the first few months after administration due to initial anti-vector immunity. For this reason, vaccine developers often use a different vector (known as a heterologous prime-boost) to augment the levels of the induced, polyfunctional CD4+ and CD8+ T cells. MVA is an exceptional boosting agent, which was derived from the smallpox vaccine by over 500 passages in avian cells. This virus is no longer able to replicate in humans, and has safely been administered to over 130,000 people. It both boosts and prolongs the CD4+ and CD8+ T cells induced by ChAdOx1 or ChAdOx2, and can be manufactured at scale using immortalized avian embryonic cell lines.

The Jenner Institute and Oxford University scientists have led the worldwide effort in using the adenoviral prime/MVA boost regimen in HIV, malaria, RSV, HCV, TB, influenza, Ebola, cancer, and HBV. Vaccitech is now using this knowledge to move its programs through the product development pathway.

Vaccitech has licensed the needed patents from Oxford University to advance all of the programs. Our ChAdOx1 vector patent is granted in the US and the EU, and our MVA-NP+M1 patent is granted in the EU and pending in the US.