Secondary targets

The term "Secondary targets" refers to a collective group of biological molecules, such as receptors, enzymes, or ion channels, that a drug substance interacts with beyond its intended primary therapeutic target (Bowes et al., 2012, Nature Reviews Drug Discovery). These interactions are a core component of a drug's "off-target" profile and are frequently responsible for side effects and adverse drug reactions (Lynch et al., 2017, Journal of Pharmacological and Toxicological Methods). In the pharmaceutical industry, secondary pharmacology screening is a critical step in drug development used to identify potential safety risks early by testing compounds against a broad panel of common secondary targets like the hERG potassium channel or various G protein-coupled receptors (Valentin et al., 2009, Expert Opinion on Drug Safety). While some secondary interactions may contribute to a drug's overall efficacy through polypharmacology, they are primarily monitored to ensure patient safety and minimize toxicity. Because "Secondary targets" is a categorical designation rather than a specific protein or gene, it does not possess a singular biological function or specific disease role. Understanding the secondary target profile of a lead compound allows researchers to optimize chemical structures to increase selectivity and reduce the likelihood of clinical failure due to safety issues. This process is essential for maintaining a favorable benefit-risk ratio for new therapeutic agents.

Other names

Off-targetsAntitargetsNon-therapeutic targetsCollateral targets

Not applicable