A personalised vaccine developed by Moderna and Merck reduced the recurrence of melanoma in a large, late-stage trial, raising expectations for treating the deadliest form of skin cancer and showing the promise of the embattled mRNA technology, reports BritPanorama.
The trial met its main goal as the vaccine, combined with Merck’s immune drug Keytruda, prevented the cancer’s return after it had been surgically removed more often than immunotherapy alone. It also slowed the spread to new areas of the body, the companies stated.
Moderna shares spiked by a record 177 per cent on the announcement, though the stock remains well short of its Covid-era highs. Merck shares climbed nearly 13 per cent. This marks the first positive final-stage trial for any mRNA-based cancer therapy, providing strong evidence that the technology behind Moderna’s Covid vaccine could lead to advances in cancer treatment.
For Merck, which is facing a patent loss for Keytruda, this development opens a key new market for future growth. “It is an important step forward for the field of cancer immunotherapy, more specifically for cancer vaccines, which have had a long but relatively unsuccessful track record until now,” noted Jedd Wolchok, a melanoma expert and director of the Meyer Cancer Centre at Weill Cornell Medicine. He emphasised that training the immune system to recognise specific cancer targets can enhance the benefits of existing immune drugs.
Details on how much the vaccine improved recurrence-free survival—the length of time a patient remains cancer-free—have not yet been disclosed. The trial is ongoing to determine if vaccinated patients have improved overall survival rates.
Melanoma is the most serious form of skin cancer, with around 112,000 new diagnoses and approximately 8,500 deaths annually in the US, according to the American Cancer Society. Additionally, the companies are planning to discuss filing for regulatory approval and will present their findings at an upcoming medical meeting. Moderna’s chief executive, Stephane Bancel, indicated that the personalised vaccine could potentially receive approval as soon as 2027.
Bancel described the trial’s outcomes as “an extraordinary milestone for mRNA science.” However, questions remain regarding the cost and feasibility of producing such bespoke cancer treatments at scale, with Keytruda’s costs exceeding $200,000 per year for some patients. Unlike many new cancer treatments, which initially target smaller patient groups, the melanoma vaccine was administered to a larger pool of patients whose tumours were completely removable.
The promising trial results arrive just after the US Food and Drug Administration approved Replimune Group’s Tudriqev for patients with advanced melanoma resistant to immune therapy. The personalised Moderna-Merck vaccine works uniquely to stimulate the immune system, having been developed using similar mRNA technology as Moderna’s Covid vaccine over a decade.
The manufacturing of each vaccine takes about six weeks, during which scientists analyse a patient’s tumour sample to identify mutations likely to provoke an immune response. According to Jane Healy, head of oncology early development at Merck, as many as 34 of these mutations can be used to create a personalised vaccine, while patients receive Keytruda during the waiting period.
The ongoing research highlights significant progress in the field, raising both hopes and questions about future treatments.
