We sought further insights into the tumor growth inhibition activity of anti-CEACAM5 CAR-T and ADC SAR408701 analog by examining their activity in a CEACAM5-negative DM4S A549 tumor model, because the ADC SAR408701 analog showed a CEACAM5-independent killing activity in vitro cell-based system. This evidence concerns the gene CEACAM5 and neoplasm.