An experimental, personalized mRNA vaccine has demonstrated a significant reduction in the risk of melanoma returning or spreading after surgical removal of the cancer. The results from a Phase 3 clinical trial, conducted by Merck and Moderna, mark a milestone for personalized cancer therapies.
The study, named INTerpath-001, involved 1,137 patients globally who had undergone surgery for high-risk melanoma (Stage IIB through Stage IV). Participants were randomly assigned to receive either Merck's immunotherapy drug KEYTRUDA alone or KEYTRUDA in combination with the personalized vaccine. Those who received the combination therapy showed significantly better "recurrence-free survival" and "distant metastasis-free survival," indicating a lower likelihood of cancer returning or spreading to distant parts of the body.
This personalized vaccine is a therapeutic treatment designed to train the patient's immune system to target and eliminate any remaining cancer cells after surgery. The process involves analyzing the genetic sequence of a patient's tumor and healthy cells to identify up to 34 unique tumor-specific neoantigens. These neoantigens are then encoded into the custom-tailored mRNA vaccine.
"These phase 3 findings represent a pivotal moment for the field of cancer research," said Stéphane Bancel, CEO of Moderna, in a press release. "For many years, the idea of creating an mRNA treatment designed specifically for an individual patient's cancer was aspirational. We are now helping turn that vision into a reality."
Dr. Murad Alam, chief of dermatology at Northwestern Medicine in Chicago, highlighted the individualized nature of the vaccine. "They're slightly different in every patient, which is why traditional chemotherapies often stop working or don't work in a particular patient," he explained. "This is almost individualized immunotherapy, where you're finding specific issues in a particular patient." He added that artificial intelligence plays a crucial role in analyzing the genetic data and developing the vaccine efficiently.
Merck and Moderna plan to consult with regulatory authorities, including the U.S. Food and Drug Administration, regarding potential filings for the treatment. The companies are also exploring the application of this vaccine technology for other challenging cancers, such as lung, bladder, and kidney cancers.
While the trial results are considered significant, the companies noted that the findings are still early. The study did not yet reveal the long-term duration of cancer-free survival or definitively establish if the treatment improves overall patient longevity. The recurrence-free survival data was based on investigator assessments, not an independent central review.
The study focused on patients with specific stages of melanoma who had undergone surgery without prior drug treatments, so the results may not be generalizable to all cancer types or stages. Side effects observed were consistent with those seen in earlier studies, with no new safety concerns identified. The vaccine was generally well-tolerated, with mild side effects such as fatigue, chills, and injection site pain, which are notably less severe than those often associated with traditional cancer therapies.