Moderna, Inc. and Merck announced that mRNA-4157/V940, an investigational personalised mRNA cancer vaccine, in combination with KEYTRUDA, Merck's anti-PD-1 therapy, has been granted Breakthrough Therapy Designation by the U.S. Food and Drug Administration (FDA) for the adjuvant treatment of patients with high-risk melanoma following complete resection. The FDA granted Breakthrough Therapy Designation based on positive data from the Phase 2b KEYNOTE-942/mRNA-4157-P201 trial. The FDA's Breakthrough Therapy Designation is granted to expedite the development and review of drugs that are intended to treat a serious condition, and when preliminary clinical evidence indicates that the product may demonstrate substantial improvement over available therapies on at least one clinically significant endpoint.

The companies will continue to discuss the results with regulatory authorities, initiate a Phase 3 study in adjuvant melanoma in 2023, and rapidly expand to additional tumor types, including non-small cell lung cancer. About mRNA-4157/V940: mRNA-4157/V940 is a novel investigational messenger ribonucleic acid (mRNA)-based personalised cancer vaccine consisting of a single synthetic mRNA coding for up to 34 neoantigens that is designed and produced based on the unique mutational signature of the patient's tumor. Upon administration into the body, the algorithmically derived and mRNA-encoded neoantigen sequences are endogenously translated and undergo natural cellular antigen processing and presentation, a key step in adaptive immunity.

Personalised cancer vaccines are designed to prime the immune system so that a patient can generate a tailored antitumor response specific to their tumor mutation signature. mRNA-4157/V940 is designed to stimulate an immune response by generating specific T cell responses based on the unique mutational signature of a patient's tumor. KEYTRUDA is an immunotherapy that works by increasing the ability of the body's immune system to help detect and fight tumor cells.

Based on early clinical studies, combining mRNA-4157/V940 with KEYTRUDA may potentially provide an additive benefit and enhance T cell-mediated destruction of tumor cells.