Drug Targets

A drug target is the specific biological macromolecule — most commonly a protein, though occasionally a nucleic acid — through which a drug produces its...

A drug target is the specific biological macromolecule — most commonly a protein, though occasionally a nucleic acid — through which a drug produces its pharmacological effect. Druggable target classes include G-protein-coupled receptors, which transduce extracellular signals through heterotrimeric G-protein cascades and represent the single largest class of clinically exploited targets; enzymes, whose catalytic activity can be selectively inhibited, exemplified by cyclooxygenase inhibition underlying NSAID action and kinase inhibition underlying much of contemporary targeted oncology; ion channels, whose gating and conductance properties can be pharmacologically modulated, underlying anaesthetic, antiepileptic, and antiarrhythmic drug classes; nuclear receptors, ligand-activated transcription factors targeted by steroid hormone and PPAR-directed therapeutics; and nucleic acids, targeted directly in oncology through intercalating and alkylating agents. A well-chosen target must be causally linked to disease pathology, structurally tractable to small-molecule or biologic modulation, and sufficiently selectively expressed that its modulation does not produce unacceptable off-target effects.