Moderna’s mRNA cancer vaccine shows promise in early trial

Moderna and Merck are preparing to launch the first ever phase 3 trial of a messenger RNA cancer vaccine after a study suggested it could be used to treat an aggressive type of skin cancer.

Data released by Moderna on Tuesday showed that a combination of the company’s experimental cancer vaccine and Merck’s immunotherapy drug Keytruda reduced the risk of death or recurrence of melanoma in high-risk patients by 44 per cent compared with treatment using only Keytruda.

The phase 2 randomised trial enrolled 157 patients who had already undergone surgery related to melanoma and tracked them for a year. Some participants received nine doses of the cancer vaccine, codenamed mRNA-4157/V940, along with Keytruda. Others were given Keytruda alone, which is the standard treatment for high-risk melanoma.

Stéphane Bancel, Moderna chief executive, said the results had emboldened Merck and Moderna to embark on a larger phase 3 trial that regulators tend to demand before approving a new treatment.

The vast majority of drugs that succeed in phase 2 studies subsequently fail in the next stage of trials.

The companies would also test the combination in other kinds of cancer. “We believe that this should work in many tumour types, not only melanoma,” Bancel said in an interview.

Moderna shares surged as much as 25 per cent to $207.37 in early trading following release of the results, while Merck shares were up almost 1 per cent.

Scientists have long studied the potential of using mRNA technology — which is best known for being used successfully in Covid-19 jabs — to deliver a vaccine that teaches the body’s immune system to target cancer tumours.

Jeffrey Weber, principal investigator of the study and deputy director of the Perlmutter Cancer Center at NYU Langone, said the findings provided the first randomised evidence that a personalised neoantigen vaccine approach could be beneficial in melanoma cases. Weber is a paid consultant for Merck and Moderna.

However, some analysts urged caution noting that Moderna had released only a small amount of trial data and the results had not yet been reviewed by independent scientists.

Daina Graybosch, an analyst at SVB Securities, said the phase 2 results were impressive but a detailed read out of the results would be needed to bolster confidence that the success could be repeated in a larger trial.

Julie Bauman, director of the cancer centre at George Washington University, said mRNA cancer vaccines are specifically tailored to target each individual’s cancer.

“You get the tissue from a tumour, sequence it and then over a six-week period of time you manufacture a vaccine that matches the top 10 to 20 mutations,” she said.

Bauman said the vaccine stimulates a person’s immune system to selectively target those cancer cells.

The clinical trial forms part of a six-year collaboration between Merck and Moderna in the field of developing personalised cancer vaccines. In October, Merck agreed to pay Moderna $250mn to exercise an option to jointly develop and commercialise mRNA-4157/V940.

Dean Li, president of Merck Research Laboratories, said the positive trial findings represented an important milestone in the company’s collaboration with Moderna.

“We look forward to advancing this programme into the next phase of development,” he said.

Additional reporting by Hannah Kuchler in London