MDA-MB-231 and PAXF1657 xenografts were developed in female athymic nude mice by implanting 5 × 106 MDA-MB-231 cells...In vivo, ADCT-601 had potent and durable antitumor activity in a wide variety of human cancer xenograft mouse models, including patient-derived xenograft models with heterogeneous AXL expression where ADCT-601 antitumor activity was markedly superior to an auristatin-based comparator ADC.