The American pharmaceutical companies Merck and Moderna have announced that a personalized cancer treatment, utilizing the messenger RNA (mRNA) technology pioneered during the COVID-19 pandemic, has successfully reduced the recurrence of melanoma tumors in a late-stage clinical trial. Described by medical experts as a major breakthrough, the trial marks the first time an mRNA-based therapeutic has demonstrated positive results in a large, late-stage study.
Following the announcement, shares of Moderna surged by 145 percent to close at $154, while Merck's stock climbed more than 12 percent to reach $152.
The experimental drug, known as "intismeran autogene," works by mapping the unique mutational signature, or genetic "fingerprint," of a patient's tumor. Researchers extract a sample of the tumor and use synthetic molecular instructions, encased in microscopic fat bubbles, to train the patient's immune system to recognize and destroy the specific cancer cells.
The clinical trial lasted approximately one year and involved 1,137 patients who had previously undergone surgery to remove their melanoma. The participants were divided randomly, with two-thirds of the cohort receiving a combination of intismeran autogene and pembrolizumab—the current standard-of-care drug—while the remaining third received pembrolizumab alone.
"Today marks an extraordinary milestone for Moderna, for mRNA science and, most importantly, for patients with cancer," said Moderna Chief Executive Officer Stephane Bancel in a statement.
Oncologists not involved in the study expressed strong optimism regarding the findings. Lennard Lee, an oncologist and assistant professor at the University of Oxford, described the results as "very encouraging" and noted that the medical community should look forward to reviewing the complete data. Marco Gerlinger, a professor at London's Barts Cancer Institute, called the trial a "breakthrough in the development of new cancer immunotherapies," noting that it serves as a "proof of principle that personalised cancer vaccines work," despite the initial press release lacking extensive details.
Melanoma remains one of the deadliest forms of skin cancer, with more than 330,000 new cases diagnosed globally in 2022. Merck and Moderna stated they plan to present their comprehensive data at an upcoming international medical conference and will begin the process of filing for regulatory approvals.
Furthermore, the drugmakers are expanding their research. Bancel confirmed that they are currently studying intismeran in combination with pembrolizumab and other anti-cancer therapies, as well as a standalone monotherapy, across multiple tumor types and stages of disease, including lung, bladder, and kidney cancers, in addition to melanoma.
