Figure 3.

Representative photomicrographs of immunohistochemistry for deruxtecan (DXd) in monkey lungs. A, B, Vehicle control, 6‐week toxicity study. No positive staining of DXd was observed. C, 78.8 mg/kg trastuzumab deruxtecan (T‐DXd), 6‐week toxicity study. No obvious DXd positive signal in the bronchiolar epithelium was detected. D, E, 30 mg/kg T‐DXd, 3‐month toxicity study. Alveolar macrophages in the alveolus as well as blood components were positive for DXd (arrows). F, 30 mg/kg T‐DXd, 3‐month toxicity study. No positive staining of DXd was detected after the 3‐month recovery period. Bar, 20 μm