Could a personalized vaccine be the answer to skin cancer?
Breakthrough research could mean personalized cancer vaccines become a reality. Melanoma, an aggressive type of skin cancer, arises from the continuous growth of pigment-producing skin cells. With stage IV having a five-year survival rate of 16.2%, effective treatments are needed promptly.
Conventional treatment supplemented with a personalized, anti-melanoma vaccine showed great promise in a recent clinical trial. The combination led to better clinical outcomes than conventional treatment on its own.1 These early findings provide hope for the future and lay the framework for larger clinical studies.
What to know about melanoma
Melanoma is the most dangerous form of skin cancer, estimated to have affected 96,480 Americans in 2019.2 It can occur in different areas of the body, including the eyes, digestive tract, or sinuses.2 However, this type of cancer typically occurs in the skin after too much exposure to ultraviolet light rays, like those from the sun.2
Alterations to the genetic makeup of the melanoma cells cause them to grow uncontrollably. Researchers are studying these alterations and their effects to develop treatments that counteract them. Likewise, when a biopsy sample is collected from a patient, the doctors analyze the tissue characteristics to determine the best course of action.2
Personalized anti-cancer vaccines
Personalized anti-cancer vaccines are a hot topic in research. They may be the solution to minimizing cancer treatment’s negative effects. Neoantigens have cancer-specific characteristics that can trigger an immune response. The anti-cancer vaccines create T-cell (immune cell) responses that fight neoantigens. Since neoantigens distinguish cancer cells from healthy cells, they are being studied as vaccine candidates. The aim is to use neoantigens to train the immune system to recognize and attack only the patient’s cancer cells.3
Unlike disease-causing agents, which is what vaccines have been typically designed for, the genetic makeup of cancer cells varies from person to person.3 Hence, studying the patient’s cancer cells and customizing a cancer vaccine to their specific characteristics gives the “personalized” touch.
A new, anti-melanoma vaccine shows promise
The mRNA-4157/V940 vaccine is a new anti-melanoma vaccine being studied in clinical trials. This cancer vaccine has a single fragment of genetic material that can code up to 34 neoantigens unique to a patient’s cancer cells. In a recent, smaller clinical trial, patients with advanced melanoma were given an existing melanoma treatment alone or in combination with the new vaccine.1 So far, the early results from this trial are promising.
The risk of cancer returning was reduced by 44% in the group of patients who received the anti-melanoma vaccine compared to the patients who did not. In addition, the risk of death in the group of patients who received the melanoma vaccine was reduced to a similar degree.1 The researchers expect to publish the complete set of results sometime in the near future.
Hope for the future
These early results are reassuring and provide hope for a new, game-changing cancer therapy. However, the results are preliminary and only a small group of patients were studied. Thus, the results are not yet generalizable to all patients with melanoma.
The results of this early-phase clinical trial will be shared with the health authorities, and researchers are planning to begin a larger, phase III study sometime in 2023.1 This will be exciting, as it will allow studying this vaccine in a larger group of patients. For now, we can remain cautiously optimistic as we let the science of this novel candidate unfold.
References
1. Moderna. Moderna and Merck announce mRNA-4157/V940, an investigational personalized mRNA cancer vaccine, in combination with Keytruda(R) (Pembrolizumab), met primary efficacy endpoint in phase 2B KEYNOTE-942 trial. Accessed March 9, 2023. https://investors.modernatx.com/news/news-details/2022/Moderna-and-Merck-Announce-mRNA-4157V940-an-Investigational-Personalized-mRNA-Cancer-Vaccine-in-Combination-with-KEYTRUDAR-pembrolizumab-Met-Primary-Efficacy-Endpoint-in-Phase-2b-KEYNOTE-942-Trial/default.aspx
2. Jenkins RW, Fisher DE.Treatment of advanced melanoma in 2020 and beyond. J Invest Dermatol. Jan 2021;141(1):23-31. doi:10.1016/j.jid.2020.03.943
3. Blass E, Ott PA. Advances in the development of personalized neoantigen-based therapeutic cancer vaccines. Nat Rev Clin Oncol. Apr 2021;18(4):215-229. doi:10.1038/s41571-020-00460-2
