How Moderna's melanoma mRNA vaccine could fight deadliest skin cancer

Moderna has announced a significant breakthrough in its experimental melanoma treatment, a vaccine that could potentially prevent the deadly skin cancer from recurring or spreading. The experimental vaccine was tested in a Phase 3 clinical trial involving over 1,100 patients with advanced melanoma. The trial, which marked a major milestone for mRNA vaccines against cancer, demonstrated that patients who received the vaccine in addition to Merck's cancer immunotherapy drug Keytruda remained cancer-free for a longer period compared to those who only received Keytruda.

The vaccine's mechanism of action involves using a personalized approach. After a patient's tumor is removed, it is analyzed to identify unique mutations present. Artificial intelligence then assists scientists in determining which of the hundreds of mutations should be included in the vaccine. Once administered, the synthetic mRNA is delivered into cells, providing a dual attack on melanoma.

The first attack involves Keytruda, which removes the tumor's cloak of invisibility that allows it to evade the immune system. The second attack involves the patient's cells reading the mRNA and building a protein, which trains the immune system to recognize and attack cancer cells, similar to training a bloodhound to hunt down a scent.

The trial's results showed that the vaccine, when combined with Keytruda, statistically and clinically improved patients' chances of staying cancer-free for a longer duration. This is particularly encouraging for patients whose melanoma had spread to the lymph nodes. Melanoma is the fifth most commonly diagnosed cancer in the United States, with around 112,000 new cases each year, and about 8,500 people in the U.S. are projected to die from melanoma this year.