The results of a clinical trial have revived hopes for the development of personalized cancer vaccines, after showing that an experimental vaccine designed specifically for each patient can reduce the risk of melanoma skin cancer recurrence.
The trial included more than 1,000 patients with high-risk melanoma, one of the most dangerous forms of skin cancer, who had undergone surgery to remove their tumors. Participants received the vaccine Entsmiran in conjunction with Keytruda, an immunotherapy drug used to treat various types of cancer.
Moderna and Merck, the developers of the treatment, said that combining the vaccine with Keytruda achieved better results than using Keytruda alone, helping to prolong the period during which patients remained cancer-free and reducing the risk of the disease spreading to other parts of the body.
The full trial data has not yet been published and is expected later this year. Therefore, more information is still needed to determine the extent of the treatment's benefit, its impact on patients' quality of life, and how its results translate into long-term survival rates.
Entsmiran is based on messenger RNA (mRNA) technology, the same technology used in the COVID-19 vaccines developed by Pfizer and Moderna. However, the new vaccine does not offer a one-size-fits-all approach; instead, it is personalized based on each patient's specific tumor characteristics.
The vaccine manufacturing process begins by analyzing a sample of the tumor removed during surgery to identify mutations in the cancer cells. This information is then used to design a patient-specific mRNA vaccine, which, after injection, trains the immune system to recognize and attack any remaining cancer cells.
These results follow a smaller Phase II trial that showed adding the vaccine to standard immunotherapy reduced the risk of disease recurrence or patient death by 49%. The trial also observed some side effects, including fatigue, injection site pain, and chills.
Moderna CEO Stéphane Bancel said the results represent "a pivotal moment in cancer research," noting that developing an mRNA therapy tailored to each patient has been a goal for researchers for many years, and that the current results bring this idea closer to practical application.
Dr. Leonard Lee, an associate professor at Oxford University and the nation’s chief clinical adviser on cancer vaccines, described the results as “significant,” noting that the trial represents a major step forward in the development of new mRNA-based cancer treatments and antigens tailored to each patient.
He added that full data from the trial will be necessary to accurately determine the magnitude of the benefit, identify the patients who benefit most from the treatment, and assess the possibility of incorporating it into the routine care of melanoma patients.
Research is not limited to skin cancer, as pharmaceutical companies are testing personalized vaccines based on the same technology to treat bladder cancer, kidney cancer, and non-small cell lung cancer.
Moderna's shares rose more than 150% on the New York Stock Exchange following the announcement of the trial results, while the company hopes, if the treatment receives the necessary regulatory approvals, to make it available to patients as early as next year.
However, the treatment is still awaiting full data and regulatory decisions, and the cost of manufacturing a separate dose for each patient and the logistical challenges associated with producing these vaccines on a large scale remain among the most prominent questions before their widespread use.
