Internalization of IMAB027 in various CLDN6+ human ovarian (OC) and testicular cancer (TC) cell lines was assessed by immunofluorescence, flow cytometry, and Fab-ZAP internalization assay....In vivo, significant antitumor effects were observed after a single intravenous administration of 16 mg/kg IMAB027–vcMMAE in mouse OC xenografts.