Antibody-drug conjugates: targeted weapons against cancer

Antibody drug conjugates (ADCs) are formed by a targeting antibody conjugated to a chemotherapeutic molecule through a linker. Recent data demonstrate that they represent a valuable advancement for the clinics and, despite their recent appearance, they are already undergoing an innovation wave aimed at targeting all their three building blocks. Thus, new antibody formats are being engineered, site-specific linkers are being designed and highly toxic molecules, like RNA polymerase inhibitors, start to be used for conjugation. These molecules were previously considered extremely toxic and could not be used as chemotherapeutic drugs. In this review, we will go through an overview of current cancer treatments and their limitations, and the logic which has led to the generation of ADCs. Their mechanism of action will be outlined and the most recent novelties in linker design and optimization will be discussed, along with present and near future of the current ADC pipeline.