An international clinical trial co-led by prominent Australian oncologist Professor Georgina Long has delivered what experts are hailing as a "phenomenal" and "transformational" breakthrough in the fight against melanoma.
The late-stage clinical trial evaluated a personalised mRNA therapeutic cancer vaccine (intismeran)—developed by Moderna and Merck—paired with the immunotherapy drug pembrolizumab (Keytruda). Results demonstrated a 42 per cent reduction in the risk of melanoma returning or resulting in death compared to immunotherapy treatment alone.
How the personalised vaccine works
Unlike traditional preventative vaccines administered to healthy individuals, this therapeutic vaccine is tailored specifically for patients who have already been diagnosed with surgically removed, high-risk melanoma (stages IIB to IV).
- Tumour sequencing: Doctors sequence a sample of the patient's surgically removed tumour to identify unique mutations and neoantigens (surface markers).
- AI-assisted targeting: Advanced tools help select the neoantigens most likely to trigger a robust immune response.
- Immune training: An individualised mRNA vaccine is manufactured to instruct the patient's immune system to locate, target, and destroy residual melanoma cells, drastically cutting the chance of recurrence or spread.
Professor Georgina Long, Medical Director of the Melanoma Institute Australia and global Principal Investigator for the trial, described the breakthrough as unprecedented in the history of cancer drug development.
"This has not been achieved before in the history of cancer drug development," Long said. "Having succeeded in melanoma, this proof of concept could mark the beginning of a foundational shift in how we treat cancer, helping patients remain cancer-free for longer," he added.
The findings come as a vital development for countries like Australia, which records some of the highest rates of melanoma globally, making it the most common cancer among young adults aged 20 to 39.
Regulatory path and next steps
While the trial results—set to be presented at the European Society of Medical Oncology and published in the New England Journal of Medicine—represent a massive medical milestone, researchers note that regulatory reviews and commercial approvals will take time.
Furthermore, because each dose must be custom-manufactured from individual tumour samples, scaling production speed and accessibility remains a future challenge. Medical experts continue to emphasise that prevention and sun-smart habits remain the best frontline defence against skin cancer.
