American pharmaceutical companies Moderna and Merck have announced positive results from the final phase of clinical trials for an experimental messenger RNA vaccine targeting advanced skin cancer.
The Phase 3 trial, which involved more than 1,100 patients, tested the personalized treatment named intismeran autogene in combination with Merck's immunotherapy drug Keytruda against Keytruda alone.
In a joint statement released on Wednesday, 19 August, the two drugmakers confirmed that the combined therapy produced a statistically significant improvement in recurrence-free survival among patients with advanced-stage melanoma who had previously undergone surgery.
The companies described the outcome as the first positive Phase 3 results announcement for an mRNA-based cancer therapy. The successful clinical trial marks a decisive step toward submitting formal applications for commercial marketing authorization.
Trial details and custom mRNA technology
The experimental treatment, intismeran autogene, relies on messenger ribonucleic acid (mRNA) technology to instruct human cells to manufacture specific proteins capable of triggering a targeted immune response. Unlike standard off-the-shelf vaccines, it is a tailor-made therapy designed specifically around the unique genetic mutations found within each patient's individual tumour.
By training and activating the patient's immune system to recognize and attack malignant cells, the vaccine aims to prevent the cancer from returning. Keytruda, an established immunotherapy drug developed by Merck, works alongside the vaccine by helping the body's immune system identify and destroy cancer cells.
Moderna and Merck announced the positive trial outcomes without publishing detailed numerical figures. Stéphane Bancel, the chief executive of Moderna, said in the statement that for many years the concept of creating an mRNA treatment customized for an individual's specific cancer had been difficult to imagine, but the companies were now helping to turn that vision into reality.
Melanoma burden and future steps
Melanoma is recognized as one of the most lethal forms of skin cancer, developing in the pigment-producing cells of the skin. Global health figures show that more than 330,000 new cases of melanoma were diagnosed worldwide in 2022, a total that continues to grow.
Moderna became widely known to the public as a global pioneer of messenger RNA technology during the coronavirus pandemic. Alongside Pfizer-BioNTech, the United States biotechnology firm was among the first in the world to develop and commercialize an mRNA vaccine against Covid-19 on a massive scale.
Following the latest clinical trial findings, Merck and Moderna plan to present their complete dataset at an upcoming medical congress. The two pharmaceutical firms will also initiate formal procedures with regulatory authorities to request commercial approval for the treatment.
