CombiVir: combinatorial engineering of therapeutic viruses

Curing cancer though stimulation of a patient's own immune system has long been a pipedream. However, recent advances have shown that two novel classes of therapies (checkpoint inhibitor drugs; CAR-T cell therapy) can achieve exactly that, albeit in very small subsets of patients and with sometimes significant side-effects. Encouraged by these results a host of further immunotherapies are urgently being pursued, both academically and in industry, to capitalise and expand on these findings. One highly promising therapy is oncolytic virus immunotherapy (OVI). Selective replication of viruses within tumours drives tumour cell death leading to release of cancer-specific antigens. Viruses trigger an immune response in tumours while delivering therapeutic payloads that stimulate immune cells within the tumour. Because these payloads are only produced within the tumour they will not have the undesired effects they currently display upon bloodstream infusion. Here we use a synthetic biology approach to engineer a novel gene expressing virus that makes great use of unique characteristics of Vaccinia virus to become a disruptive technology in the treatment of cancer.