mRNA-4203

mRNA-4203 is an **off-the-shelf mRNA-based immunotherapy** developed to encode the cancer-testis antigen **PRAME (Preferentially Expressed Antigen in Melanoma)**. It is designed to boost anti-tumor immune responses, specifically as a combination therapy with Immatics' PRAME-directed engineered T-cell receptor product, IMA203. The mRNA-4203 product delivers PRAME-encoding mRNA, which is intended to enhance presentation of PRAME antigen, thereby augmenting the activity of TCR-T cell therapy against PRAME-positive tumors, such as melanoma and synovial sarcoma. The drug is being developed through a collaboration between Moderna and Immatics as part of Moderna’s oncology pipeline focused on mRNA cancer antigen therapies. The mechanism of action relies on the production of PRAME antigen in vivo, leading to heightened immune recognition and destruction of tumor cells expressing this antigen.[4][10]