Moderna previewed early clinical data for its cancer antigen mRNA program (mRNA‑4359) in melanoma patients ahead of ESMO and disclosed that those results informed internal decisions to prioritize an IDO‑focused oncology strategy. The company reported responses in patients who had failed prior checkpoint inhibitors when mRNA‑4359 was combined with Merck’s PD‑1 inhibitor. Moderna also released additional Phase 1/2 melanoma data that the company cited as rationale for expanding its oncology portfolio to include IDO modulation, a pathway with a checkered history but renewed interest when paired correctly with antigen and checkpoint strategies. The disclosures underscore Moderna’s pivot from vaccine‑only playbooks toward complex, combination‑dependent cancer immunotherapies and set expectations for fuller datasets to appear at upcoming congresses.