Tirzepatide is approved for type 2 diabetes and obesity. What is unique about its receptor pharmacology?
- A It is a selective GLP-1 receptor agonist with higher receptor affinity than semaglutide
- B It is a triple agonist at GLP-1, GIP, and glucagon receptors
- C It is a dual agonist at both GLP-1 and GIP receptors (twincretin) ✓
- D It inhibits DPP-4 and activates GLP-1 receptors simultaneously
Correct answer: C. It is a dual agonist at both GLP-1 and GIP receptors (twincretin)
Explanation
Tirzepatide is a once-weekly dual GIP/GLP-1 receptor agonist (the first 'twincretin'). It acts as a full agonist at GIP receptors and a partial agonist at GLP-1 receptors. This dual incretin activity produces superior HbA1c reduction and weight loss compared to selective GLP-1 receptor agonists like semaglutide in head-to-head trials (SURPASS programme). Triple agonism (GLP-1, GIP, glucagon) describes retatrutide, a separate investigational agent.
Reference: KD Tripathi, Essentials of Medical Pharmacology, 8th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.