Virkningsmål

Virkningsmål is the biological molecule or pathway that a drug binds to or modulates in order to produce its therapeutic effect. In pharmacology, the virkningsmål (drug target) is the primary focus of drug action and helps explain how a compound achieves efficacy and how side effects may arise. Most virkningsmål are proteins, including receptors, enzymes, transporters, and ion channels, but they can also be nucleic acids or larger protein complexes involved in disease pathways.

Common examples include the beta-adrenergic receptor targeted by beta-blockers, HMG-CoA reductase targeted by statins, and cyclooxygenase enzymes targeted by NSAIDs. In cancer therapy, targets such as PD-1/PD-L1 and HER2 illustrate how targeting specific molecules can alter tumor biology. Drug discovery aims to identify useful virkningsmål, confirm that manipulating the target produces the desired effect (validation), and develop ligands with appropriate affinity, selectivity, and pharmacokinetic properties.

The interaction between a drug and its virkningsmål underpins pharmacodynamics, while the broader biology of the target influences safety and efficacy. Challenges include redundancy in biological networks, compensatory pathways, off-target interactions, and the potential for resistance. Understanding virkningsmål is essential for rational drug design, maximizing therapeutic benefit, and minimizing adverse effects. In modern medicine, genetic variation can affect target expression or drug binding, contributing to interindividual differences in response.