Measuring Drug Target Success

Modern drugs usually have known targets — molecules in the human body, which the drug works by chemically interacting with. Historically, many drugs were discovered empirically, before their mechanism of action was known. Some drugs, like penicillin and aspirin, were identified as the active ingredients in natural products found to be effective (against bacteria and pain, respectively). But today it’s more common for drugs to be intentionally designed to target a specific molecule (often a prote...