Metabolite

A metabolite is any substance produced during metabolism, including both the intermediate and end products of enzymatic biochemical transformations. In pharmacology, metabolites are the breakdown products formed when the body processes a drug or peptide through phase I reactions (oxidation, reduction, hydrolysis) and phase II reactions (conjugation for excretion). Peptide metabolites are typically generated by proteolytic cleavage by enzymes such as DPP-4, neprilysin, and various endopeptidases. Understanding metabolite profiles is important for assessing a peptide's duration of action, potential for active metabolites (which may retain biological activity), and clearance pathways. Some metabolites can have distinct biological effects from their parent compound, which is why comprehensive metabolite analysis is included in advanced pharmacokinetic studies.