Off-the-shelf cancer vaccine could lower risk of relapse, study suggests

An off-the-shelf cancer vaccine has shown potential in lowering the risk of pancreatic and colorectal cancer returning after surgery.

The jab works by training the immune system to target and destroy cancer cells that may return after treatment, aiming to reduce relapse.

Unlike personalised mRNA vaccines tailored to individual tumours, this non-personalised vaccine is already in scaled production and could be quicker and less costly to deliver.

Researchers from the University of California, Los Angeles, tested the ELI-002 2P vaccine on 25 patients – 20 with pancreatic cancer and five with colorectal cancer – who had undergone surgery.

The vaccine contains peptides, long chains of amino acids that form proteins. It trains T-cells, a type of immune cell, to recognise and attack cancer cells with specific mutations in the Kras gene.

These mutations, present in about 90 per cent of pancreatic cancers and half of colorectal cancers, cause uncontrolled cell growth.

At a median follow-up of almost 20 months, patients fell into two groups: 17 who mounted a strong immune response and eight with a weaker response.

Those with stronger responses had longer cancer-free periods and better survival rates. Four of the 17 strong responders died during follow-up, compared with seven of the eight weak responders.

Professor Zev Wainberg is an oncologist at the University of California, Los Angeles and study co-author.

The researcher said: “After a long-term follow-up of this study, we were able to demonstrate that the group of patients who mounted an immune response have a greater likelihood of not having their cancer return and living longer compared to historical expectation of what that patient would do.”

The early-stage research primarily assessed safety and involved a small number of patients, had no control group, and looked at two cancer types at once.

Professor Siow Ming Lee, medical oncology specialist at University College London, who was not involved in the study, said the vaccine might be combined with other immunotherapies.

He said: “With promising early results and potentially fewer side-effects than current oral inhibitors, this off-the-shelf cancer vaccine could expand treatment options for Kras-driven cancers and warrants further testing in larger trials, including exploring its potential use in lung cancers driven by mutations in Kras gene.”

The NHS in England is trialling various cancer vaccines through its Cancer Vaccine Launch Pad programme, as researchers worldwide explore different approaches to preventing cancer recurrence.