‘Landmark’: New mRNA vaccine could prevent skin cancer from returning, companies say

New York: Moderna and Merck said a personalised mRNA cancer vaccine reduced the risk of recurrence and spread of melanoma in a late-stage trial, a major success in a new field of cancer treatment that sent Moderna’s shares surging more than 170 per cent.

The companies tested the vaccine together with Merck’s immunotherapy drug Keytruda, a widely used melanoma treatment. Thousands of patients who have undergone surgery to remove high-risk melanoma tumours could benefit as soon as next year if regulators approve the vaccine, Moderna president Stephen Hoge said in an interview on Wednesday (US time).

This is the first positive late-stage trial result for an mRNA cancer vaccine, which trains a patient’s immune system to fight tumours by targeting specific mutations in those cells, and the first such study to show that adding a treatment to Keytruda worked better than that therapy alone. Merck, Moderna and other companies are testing similar approaches against lung, breast and pancreatic cancers.

Karen Knudsen, CEO of the Parker Institute for Cancer Immunotherapy, said the Moderna results could signal a new era for treating solid-tumour cancers.

“The positive hit here leads us into truly this next phase in immunotherapy,” Knudsen said. “This is an auspicious start – this is where things begin.”

The results signalled a reversal of fortune for Moderna, which has struggled to generate new products beyond its COVID-19 vaccine and faced pushback over its mRNA technology from US President Donald Trump’s administration.

US Health and Human Services Secretary Robert F. Kennedy Jr has criticised the safety and efficacy of mRNA vaccines and cut $US500 million ($702 million) in mRNA vaccine projects. Still, the National Cancer Institute has continued to fund trials of cancer vaccines, including those based on mRNA.

Moderna shares surged to multiyear highs, adding about $US40 billion to the company’s market capitalisation. Merck climbed 12 per cent on hopes the vaccine would expand its prospects in cancer as Keytruda, once the world’s best-selling drug, faces patent expiration later this decade.

The vaccine – which is a personalised treatment – could be difficult to make and scale up commercially, although Hoge said Moderna was confident it could meet demand over the next few years.

The companies did not provide detailed results, which they said they would share at an upcoming medical meeting.