Preclinical studies of HLX42 demonstrated its superior efficacy over an anti-EGFR-GGFG-DXd ADC in lung cancer xenografts (8 mg/kg), supporting the idea that the novel HLX42 linker and topoisomerase payload may confer improved efficacy over validated linker–payloads on FDA-approved ADCs (i.e., GGFG-DXd on trastuzumab deruxtecan). Here, EGFR is linked to lung carcinoma.