Antibody-drug conjugates (ADCs) are strategically designed formulations for the targeted elimination of cancer cells without causing severe side effects. ADCs first recognise and bind to specific receptors on cancer cells and then enter the cells via endocytosis. Inside the cells, the cytotoxic agent attached to the ADC is released and kills the cells by disrupting the latter's defined target. Despite their superior efficacy over classic chemotherapeutics, ADCs face drug resistance in some patients. Novel ADCs are in development to address these challenges.