A tailored and efficacious cancer vaccine platform

Researchers at the University of Helsinki have discovered a solution in the form of a cancer vaccine platform for improving the efficacy of oncolytic viruses used in cancer treatment.

Researchers at the Faculty of Pharmacy at the University have developed PeptiENV, a cancer vaccine platform, which can be used to improve the therapeutic efficacy of oncolytic enveloped viruses currently in clinical use. With the help of this new cancer vaccine platform, the activation of the human immune response against cancer cells becomes significantly more effective.

“What is actually the most remarkable insight concerning the PeptiENV cancer vaccine platform is that we are able to envelop oncolytic viruses with the patient’s own cancer peptides, enabling tailored targeted treatment,” said Dr Erkko Ylösmäki, an Academy of Finland post-doctoral researcher working in the ImmunoViroTherapy Lab of the Faculty of Pharmacy, University of Helsinki.

Oncolytic viruses are naturally occurring viruses that have been modified to restrict their division only into cancer cells. Virotherapy is usually administered as an injection to the tumour or the abdominal cavity, or intravenously.

A virus enveloped with peptides through the PeptiENV platform can effectively “train” the patient’s own, locally active T-cells to identify tumour cells. Thus, the amount of T-cells able to identify tumour cells increases in the cancerous tissue, improving the efficacy of the cancer therapy.

The study demonstrated the functionality of the PeptiENV cancer vaccine platform in conjunction with oncolytic enveloped herpes simplex virus 1, already used in the treatment of metastatic melanoma. Oncolytic vaccinia viruses, among others currently under investigation in clinical trials, are also compatible with the cancer vaccine platform.

Additionally, the number of T-cells in the cancerous tissue that are able to identify cancer cells strongly correlates with the therapeutic effect of new immune checkpoint inhibitors.

“We aim to expand the pool of patients that could potentially benefit from the unparalleled efficacy of immune checkpoint inhibitors,” Dr Ylösmäki explained.