In what has been described as a paradigm shift in the treatment of melanoma, drug therapy looks set to become the standard treatment for high-risk early stage melanoma patients to stop disease spread and save lives.

Promising results from an international multi-centre clinical trial, which included researchers and patients from Melanoma Institute Australia (MIA), were presented this weekend at the prestigious European Society for Medical Oncology (ESMO) Congress.

Results showed giving high-risk Stage II melanoma patients the same immunotherapy drugs approved for use in advanced melanoma patients, reduced the risk of their disease returning or death by 35%.

Study author Professor Georgina Long AO, Co-Medical Director of Melanoma Institute Australia and of The University of Sydney, said the findings would result in a paradigm shift in treatment of early stage patients.

‘We are using drug therapy already proven to be life-saving for advanced melanoma patients, to stop the disease in its tracks in earlier stage patients,’ Professor Long said. ‘These exciting clinical trial results are strong evidence to support approval for this immunotherapy to become standard treatment for high-risk Stage II patients in Australia.’

The clinical trial demonstrated that giving pembrolizumab (Keytruda™) after surgery to patients with Stage IIB or IIC melanoma (deemed at high risk of spread due to tumour thickness or ulceration) reduced the risk of the disease returning or death by 35% compared to placebo. At 12 months, only 9.5% of patients on pembrolizumab had their melanoma progress, compared to 16.9% in the placebo group.

In the last decade, the approval of immunotherapy for Stage III and IV melanoma patients has dramatically increased survival rates, with more than 50% of these patients now essentially cured.

However, there are no immunotherapy drugs currently approved for use in Stage II melanoma patients. They instead have to adopt a ‘watch-and-wait’ approach after surgery to see if their cancer will return or spread. Patients with thick Stage II melanoma also often undergo an invasive Sentinel Node Biopsy to check for disease spread, with drug therapy only available once their disease has spread to their lymph nodes (Stage III).

Fellow study author Professor Richard Scolyer AO, Co-Medical Director of Melanoma Institute Australia and of The University of Sydney, says the clinical trial results stand to transform how earlier stage disease is managed.

‘By giving this immunotherapy treatment at an earlier stage, we are proactively preventing melanoma spread,’ Professor Scolyer said.

Australia has the highest melanoma rates in the world with one person diagnosed with the disease every 30 minutes. An estimated 1300 Australians are expected to die from melanoma this year.

Following these clinical trial results, it is hoped pembrolizumab will soon come before the Pharmaceutical Benefits Advisory Committee (PBAC) for approval for use in these patients in Australia.

‘This proactive approach to preventing disease spread represents a significant step forward in our mission of reaching zero deaths from melanoma,’ Professor Scolyer added.

The full data set was presented at ESMO on Saturday 18 September 2021 at 11:05pm (AEST) by Associate Professor Jason Luke in a presentation entitled: “Pembrolizumab versus placebo after complete resection of high-risk stage II melanoma: Efficacy and safety results from the Keynote 716 double-blinded phase III trial”.

Melanoma Institute Australia is affiliated with The University of Sydney and Professor Scolyer and Professor Long lead the Translational Research Group at the Charles Perkins Centre.