Immunome Inc. announced the presentation of preclinical data for its proprietary antibody-drug conjugate $(ADC)$ payload HC74 at the AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics, held in Boston on October 23, 2025. The data demonstrate that HC74, a novel topoisomerase I inhibitor, overcomes multiple mechanisms of ADC resistance, including payload efflux and target heterogeneity. HC74 is used as the payload in IM-1021, a ROR1-targeted ADC currently in a Phase 1 trial for solid and liquid tumors, as well as in several preclinical candidates in Immunome's pipeline. The results showed that HC74 retains efficacy in tumor models with over-expression of drug efflux transporters and in models of colorectal cancer and non-small cell lung cancer resistant to existing therapies. The full poster is available on Immunome's website.