Although in the breast cancer study TROPION-B01 there was no association between Trop2 expression levels and clinical response to Dato-Dxd in patients, our study results demonstrating a correlation between TROP2 expression and preclinical activity are in agreement with previous preclinical work with other ADCs (i.e., SG) targeting TROP2 (43). This evidence concerns the gene TACSTD2 and breast cancer.