The treatment of many cancers is being revolutionised by immunotherapies such as the checkpoint inhibitors Keytruda® (Merck; pembrolizumab) and Opdivo® (Bristol-Myers Squibb; nivolumab). Although these therapies can improve the long-term survival of cancer patients, only a minority of patients with certain types of cancers respond and there is no benefit at all in patients with other types of cancers. The challenge to immuno-oncology is therefore to improve the proportion of patients that respond well to therapy.
Vaccination is a well-established method for the prevention of diseases and has proven to be particularly effective as a prophylactic treatment against many viruses. The development of cancer vaccines to treat cancer have been more challenging. The main goal is to increase the activity of the immune response against tumour cells and this requires the induction of high-avidity, cytotoxic T cells. This in turn requires the careful selection of cancer antigens or epitopes (short amino acid sequences that make up part of the protein) and an effective delivery mechanism.
Since the outbreak of the COVID-19 pandemic, several groups have initiated programmes to produce a vaccine. The vast majority of these have focused on generating virus-neutralising antibodies (VNAbs) and not on stimulating high avidity T cell responses; importantly, the latter have been shown to correlate with mild disease in China. In contrast, our aim is to produce a simple, cost effective and scalable vaccine that gives durable T cell responses plus VNAbs, potentially conferring better protection in the long-term.