These parameters are not academic abstractions. A safe drug might require a high affinity for the target but low affinity for off-target sites (selectivity). A partial agonist (low efficacy) might be ideal for a system where full activation would be toxic—such as in opioid receptors for pain management.
The liver’s cytochrome P450 (CYP) enzyme family is the gatekeeper of drug persistence. Pharmacologists study metabolic stability: Is the drug rapidly broken down into inactive metabolites (requiring frequent dosing) or into toxic intermediates (as seen with acetaminophen overdose)? are predicted here. If a new drug inhibits CYP3A4, it could dangerously elevate levels of co-administered statins or anticoagulants. pharmacology in drug discovery and development