Skin cancer patients could soon benefit from revolutionary risk-slashing vaccine

Melanoma is one of the most aggressive and fatal types of skin cancer, with just under 1,500 people diagnosed each year in Ireland.

It is the fourth most common cancer here, and the number of people diagnosed is expected to double by 2045. In about half of patients, the disease will come back within the first five years of treatment.

The American Society of Clinical Oncology’s (ASCO) annual meeting in Chicago yesterday heard that a personalized mRNA vaccine promises to halve the risk of melanoma returning after five years.

The research has been welcomed by cancer patients and campaigners in Ireland. However, they called for greater speed in moving the drug from the trial stage to frontline access by patients.

The vaccine, intismeran, helps the immune system recognize cancer cells and therefore better respond to routine immunotherapy.

Results from a clinical trial have now shown that adding the vaccine to standard treatment can slash the risk of recurrence or death by 49%. It could also mean that mRNA vaccines could help in the fight against other hard-to-treat diseases including lung, breast and bladder cancers.

The clinical trial – led by experts at NYU Langone Health in the US – followed 157 patients who were randomly selected after surgery to receive either both the vaccine and a type of immunotherapy called pembrolizumab, or pembrolizumab alone.

After five years, around 69% of patients who had received the combined therapy remained cancer-free, while just 49% of patients who received the current standard of care showed no signs of cancer.

Adding the vaccine also reduced the risk of the cancer spreading to another part of the body, where it becomes far more difficult to treat, by 59%. Overall, adding intismeran cut the risk of the cancer returning or death by 49%.

Dr Janice Mehnert, the study’s lead author, said: ‘This offers strong evidence for melanoma patients that intismeran vaccine therapy, when used in combination with [standard treatment], can demonstrably reduce their risk of having their cancer return and improve clinical outcomes.

‘Our findings also serve as encouragement to cancer researchers globally that mRNA vaccines like intismeran could work well in combination with immunotherapy for other cancers whose high rates of mutations have proven difficult to target.’

Because the patients involved in the study had had their tumors removed, the scientists were able to analyze the tumors for mutant proteins that were specific to each cancer and create a personalized vaccine for each patient.

A phase-three multi-center clinical trial is now underway to determine whether the vaccine could be used as a first-line treatment before surgery to shrink tumors, create a stronger immune response, and reduce the chance of recurrence.

The vaccine is already being tested to see if it can prevent a number of other cancers, including lung cancer, from returning.

Unlike many cancer treatments, intismeran is given as a jab into a lymph node in the armpit or groin – rather than via an intravenous drip – once every three weeks, making treatment quicker and more convenient for patients.

Orla Dolan, chief executive of Irish charity Breakthrough Cancer Research, said: ‘These results are extremely encouraging and offer an exciting glimpse into what the future of cancer treatment may look like.

‘Personalized cancer vaccines have the potential to fundamentally change how we approach cancer care, and while more research is needed, findings such as these demonstrate why investment in innovative research is so important. Every meaningful advance begins with research, and studies like this help bring us closer to more precise, effective treatments.’

Miriam Staunton, cancer survivor and spokeswoman for Melanoma Support Ireland, said: ‘From an Irish patient’s perspective, obviously, we like to see breakthroughs like this. It is so exciting to see improved treatments coming down the line.

‘The difficulty is the distance away that it is, realistically. It is still at the trial phase. It could then take a year or so to get regulatory approval, and then it has to go through the HSE’s drug reimbursement process. On average, it takes two years for a new cancer drug to become available.

‘So realistically, we are looking at between three and four years, maybe five. It’s exciting to see it [the new drug] but it is not going to benefit patients now, it will benefit patients in the future who have not been diagnosed yet.’

She continued: ‘For Irish patients, it’s wonderful to see this research done, but we need access to these drugs much faster. American private patients are likely to have it within a couple of years. Irish private patients will also have it before public patients, which is not fair and not what private insurance should be about.

‘Everyone should have access to the best cancer care available. When you have cancer, and you see a new drug available, you want it now – not later. We are always being told to catch cancer and treat it as soon as possible for the best outcome.’

Dr Claire Kilty, head of research at the Irish Cancer Society – who is attending this year’s ASCO meeting – commented that she was delighted to be witnessing the groundbreaking results presented at the world’s largest cancer conference.

She said: ‘One of the most exciting developments in recent years has been the use of mRNA vaccines, the same technology used in Covid vaccines, in cancer research.

Kevin Keegan wants to ‘say goodbye properly’ after stage four cancer diagnosis ‘It is particularly important because patients with aggressive melanoma face a significant risk of their cancer returning.’

However, she cautioned: ‘While these findings are very promising and represent some of the strongest evidence to date for mRNA vaccines in cancer treatment, the trial is still at an early stage.

‘Larger studies with more patients are already underway, and their results will be critical in confirming these benefits.’

Additional reporting by Zoe Hardy

* This article was originally published on Extra.ie.