The preliminary RP2 trial has shown startlingly impressive results (Image: GETTY)
A ‘Trojan Horse’ treatment using a modified cold sore virus to kill cancer cells has been hailed a “marvel of genetic engineering” – with an early trial already extending terminal sufferers’ lives. The new oncolytic virotherapy treatment tested at three UK hospitals injects the drug ‘RP2’ – a modified version of the ‘cold sore’ herpes simplex virus (HSV) – directly into patients’ tumours to kill the cancer.
The engineered virus attacks cancer in a ‘one-two punch’ – first invading the cancerous cells and making them burst, then triggering the immune system’s Cytotoxic T cells to kill virus-infected cells.
And the preliminary RP2 trial has shown startlingly impressive results – with three out of nine gravely-ill cancer patients seeing their deadly tumours shrink.
Currently only 16 people worldwide with advanced cancers have had the treatment in RP2’s initial phase- one trial but a new study aims to test it on 30 patients, 24 of whom will have solid tumours.
The global trial’s UK patients are being treated at three NHS sites – The Christie, London’s Royal Marsden and the Clatterbridge Hospital, on the Wirral – however as a phase one trial it will be a while before this could be a widely-offered NHS treatment.
Professor Hans-Ulrich Laasch, interventional radiologist at The Christie, who administered their trial patients’ injections said: “We injected the virus directly inside the tumours in the liver using ultrasound to guide us.
“This real-time imaging technique to administer a virus into the lesions in the liver could potentially help patients with many types of solid tumours that have spread.
“Larger and longer studies will be needed, but the injection could offer a lifeline to more people with advanced cancers.”
The Christie is a specialist cancer centre in Manchester and has more than 120 years of expertise in cancer care, research and education. It is one of Europe’s leading cancer centres, treating over 60,000 patients a year.
The procedure is called oncolytic virus therapy (OVT) which is a new kind of immunotherapy – a type of cancer treatment that helps your immune system fight cancer.
OVT uses natural or genetically modified viruses to specifically infect and kill cancer cells without harming healthy cells.
Gabriel Perez Carol with wife Lidia and daughter Xiana (Image: Handout)
This trial is using a new drug OVT called RP2, designed to grow in, and destroy cancer cells – manufactured by US-based biotechnology company Replimune Inc., a firm initially founded in Oxford.
Construction worker Gabriel Perez Carol, 47, started the new treatment last month after being given just six months to live with stage-4 cancer – when a tumour in his throat spread to his liver and stomach.
Now Gabriel, of Levenshulme, Manchester, hopes RP2 can enable him to keep enjoying precious family time with wife Lidia, and their 9-year-old daughter Xiana with his fortnightly injections at The Christie.
He said: “This trial is giving me the chance to enjoy more time with my wonderful wife and beautiful daughter, so I am just focusing on that and taking each stage at a time.
“The liver is a sensitive organ so the procedure is very intense and painful but I knew I was in safe hands and I was looked after very well.
“And the virus fighting the cancer made me feel very unwell like a bad bout of flu’ with very bad headaches and fatigue -I’m not looking forward to going through it all again in two weeks’ time!”
Dr Sara Valpione (Image: Handout)
Gabriel was initially diagnosed in April 2021 with stage-3 oesophagus cancer after taking medication for what was believed to be indigestion for 18 months.
An endoscopy – camera put down the throat – identified a tumour the size of a tennis ball and he was immediately given chemotherapy to reduce the size of the tumour ahead of surgery.
When cancer was also discovered in the opening of the stomach, just a week before the operation, doctors made the difficult decision to remove Gabriel’s stomach and he underwent a total gastrectomy.
Unfortunately last summer he started to experience a pain in his side and doctors discovered the cancer had spread to his liver and he was diagnosed with stage-4 stomach cancer with the devastating prognosis of just six months without treatment.
With no option left apart from end-of-life care, Gabriel asked about clinical trials, and in March 2023 he was found to be eligible for the RP2-001-18part 2b study at The Christie.
Dr Sara Valpione, consultant oncologist at The Christie NHS Foundation Trust told the Daily Express: “The Christie is very excited to be part of this ground-breaking global clinical trial run by a US-based bio-tech company called Replimune.
“We’re able to offer this new experimental treatment to patients with cancer in the oesophagus or stomach that has spread to the liver.
“Scientists believe oncolytic virotherapy, which is what the treatment is called, could change the way many cancers are treated in the future.
“We know how dangerous viruses can be, but thanks to modern technology and cancer scientists, viruses can also be used for good.
“With this new treatment, that is currently only available within clinical trials, the herpes virus that causes cold sores, is genetically modified to enter the tumour and fight the cancer like a Trojan horse.
“This new virus acts in two ways. Whilst it damages the cancerous cells, it also makes them more attractive to our own immune defences, so that they can be targeted by the immune system and killed.
“Scientists weakened the virus to minimise the risks for patients, as an important part of the trial is to constantly monitor its safety.
“Along with the virus, the patients will also receive immunotherapy to boost the body’s immune-system and help the body destroy cancer cells.
“This treatment could offer a lifeline for patients who have not responded to conventional medicines, with the hope of not only seeing a response but possibly achieving remission for people with incurable cancers.
“It really is a marvel of genetic engineering which has shown promising early results, adding to our arsenal which is rapidly getting more varied and technologically advanced.
“Injecting a cancer-killing virus into tumours sounds like something out of a science fiction movie. It’s still a long way off being available on the NHS, but we hope that one day it will be a standard treatment for patients like Gabriel.”
