Tirzepatide is a first-in-class dual glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1) receptor co-agonist, engineered as a single synthetic peptide with balanced activity at both incretin receptors. The GIP component, long underappreciated in metabolic pharmacology, synergizes with GLP-1 signaling to produce superior glycemic control and weight reduction compared to GLP-1 receptor agonism alone — an effect confirmed in the landmark SURPASS and SURMOUNT clinical trial programs. Tirzepatide is approved as Mounjaro for type 2 diabetes and Zepbound for chronic weight management, with Phase 3 data demonstrating up to 22.5% mean body weight reduction. It is a foundational research tool for studying dual incretin biology, adipose tissue metabolism, insulin secretion dynamics, and the emerging cardiovascular and hepatoprotective effects of incretin-based therapies.
