molecules Review Antibody–Drug Conjugates for Cancer Therapy Umbreen Hafeez 1,2,3, Sagun Parakh 1,2,3 , Hui K. Gan 1,2,3,4 and Andrew M. Scott 1,3,4,5,* 1 Tumour Targeting Laboratory, Olivia Newton-John Cancer Research Institute, Melbourne, VIC 3084, Australia;
[email protected] (U.H.);
[email protected] (S.P.);
[email protected] (H.K.G.) 2 Department of Medical Oncology, Olivia Newton-John Cancer and Wellness Centre, Austin Health, Melbourne, VIC 3084, Australia 3 School of Cancer Medicine, La Trobe University, Melbourne, VIC 3084, Australia 4 Department of Medicine, University of Melbourne, Melbourne, VIC 3084, Australia 5 Department of Molecular Imaging and Therapy, Austin Health, Melbourne, VIC 3084, Australia * Correspondence:
[email protected]; Tel.: +61-39496-5000 Academic Editor: João Paulo C. Tomé Received: 14 August 2020; Accepted: 13 October 2020; Published: 16 October 2020 Abstract: Antibody–drug conjugates (ADCs) are novel drugs that exploit the specificity of a monoclonal antibody (mAb) to reach target antigens expressed on cancer cells for the delivery of a potent cytotoxic payload. ADCs provide a unique opportunity to deliver drugs to tumor cells while minimizing toxicity to normal tissue, achieving wider therapeutic windows and enhanced pharmacokinetic/pharmacodynamic properties. To date, nine ADCs have been approved by the FDA and more than 80 ADCs are under clinical development worldwide. In this paper, we provide an overview of the biology and chemistry of each component of ADC design. We briefly discuss the clinical experience with approved ADCs and the various pathways involved in ADC resistance.