More than 80 per cent of mice in the trial saw a complete elimination of their brain tumour, with no toxicity and no tumour recurrence.
The findings provide compelling evidence for a ‘one and done’ approach to treating human glioblastoma, the most lethal form of brain cancer, experts say.
The innovative treatment is built on more than a decade of research led by Professor Steve Pollard at the University of Edinburgh. The technology was spun out into biotech company Trogenix in 2023, supported by Edinburgh Innovations, with the goal of speeding up development from the lab and into patient trials.
The technology is initially being tested in glioblastoma, but the Trogenix team hopes that the technique can be used for other cancer types, targeting solid tumours.
Gene therapy
Using a ‘Trojan horse’ approach, the gene therapy – a specially engineered piece of DNA – is delivered to cells hidden inside a harmless virus, which is injected into the tumour.
The DNA contains three important instructions, designed to destroy the tumour.
The first – a synthetic super enhancer (SSE) – acts like a sensor, only switching on inside glioblastoma cells, ensuring the treatment targets the right place.
The second is a protein that converts a separate, inactive drug – taken as a tablet – into a toxic one, killing the glioblastoma cell.
The third triggers a powerful immune signal that wakes up the immune system and tells it to attack the tumour.
Lasting protection
The result is a two-pronged attack. The toxic drug kills cancer cells locally, while the immune signal stimulates the immune system to attack the tumour.
Mice treated with the gene therapy saw their tumours shrink dramatically within the first two weeks, with complete tumour clearance in 83 per cent of treated cases over the next three weeks.
The process also teaches the immune system to detect the cancer if it returns, providing long-term protection. Researchers found no tumour regrowth in mice after the initial treatment, and no detectable tumour formation in mice re-challenged with the cancer.
Precision targeting
Using fresh patient glioblastoma tissue samples, scientists were able to demonstrate that the gene therapy was only switched on in tumour cells, leaving nearby healthy cells untouched.
The SSE technology allows the treatment to specifically target cancer cells in a way previous therapies have not managed. This selectivity could help reduce the risk of side-effects in patients, experts say.
The next step will be early-stage clinical trials in humans, which are due to begin in Spring 2026. The initial focus of these trials will be to ensure the safety of the treatment.
The research, published in the journal Nature, was funded by Cancer Research UK and the Biotechnology and Biological Sciences Research Council (BBSRC).