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Metabolic℞ Prescription medicine

Tirzepatide

LY3298176MounjaroZepboundGIP/GLP-1 dual receptor agonisttirzepatide (sodium salt)

Tirzepatide is a synthetic, fatty-acylated 39-residue peptide that acts as a dual GIP and GLP-1 receptor agonist and is an FDA-approved prescription medicine (Mounjaro/Zepbound).

Overview

Tirzepatide (development code LY3298176; brand names Mounjaro and Zepbound) is a synthetic 39-amino-acid peptide developed by Eli Lilly. It is described in the literature as the first-in-class dual agonist of the GIP and GLP-1 incretin receptors. Structurally it is a linear peptide based on the native GIP sequence, carrying non-coded aminoisobutyric acid (Aib) residues at positions 2 and 13, a C-terminal amide, and a C20 fatty-diacid (eicosanedioic acid) chain conjugated to the lysine at position 20 through a gamma-glutamate / di-AEEA linker. The fatty-acid acylation drives high-affinity albumin binding and, together with the DPP-4-resistant Aib substitutions, gives an elimination half-life of roughly 5 days that supports once-weekly subcutaneous dosing.

By co-activating both incretin receptors, tirzepatide is reported to enhance glucose-dependent insulin secretion, suppress glucagon, and slow gastric emptying. It was approved by the US FDA as Mounjaro (2022) for type 2 diabetes and as Zepbound (2023) for chronic weight management, each supported by large randomized controlled trials. The US prescribing information carries a boxed warning for thyroid C-cell tumors observed in rodents and contraindicates use in people with a personal or family history of medullary thyroid carcinoma or MEN 2.

Tirzepatide is a licensed prescription medicine, not a research-only compound. Within scientific work it functions chiefly as a benchmark dual incretin co-agonist for studying receptor signaling and as a comparator in the development of newer multi-agonist metabolic peptides such as retatrutide. Material offered outside a regulated pharmacy supply chain is unverified and may differ in identity, purity, or concentration from the approved product.

Mechanism, evidence & status

Tirzepatide is a synthetic 39-amino-acid peptide that acts as a dual agonist of the glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1) receptors, the two principal incretin receptors. By co-activating both pathways it is reported in the literature to enhance glucose-dependent insulin secretion, suppress glucagon, and slow gastric emptying. A C20 fatty-diacid moiety conjugated at Lys20 promotes albumin binding for an extended half-life, and aminoisobutyric acid (Aib) substitutions confer resistance to DPP-4 degradation.

Human evidence
High — approved drug with large randomized controlled trials and FDA labeling
Regulatory status
FDA-approved prescription medicine (Mounjaro 2022, Zepbound 2023); carries US boxed warning for thyroid C-cell tumor risk; licensed, not research-only.
Research applications
  • Investigated in metabolic research as a model dual incretin (GIP/GLP-1) receptor co-agonist for studying receptor signaling and crosstalk.
  • Used as a reference compound in studies of glucose homeostasis, insulin secretion, and body-weight regulation.
  • Examined in research on extended-half-life peptide design (fatty-acid acylation, Aib substitution, albumin binding).
  • Serves as a comparator/benchmark in development of newer multi-agonist metabolic peptides such as retatrutide.
Safety considerations
  • US prescribing information carries a boxed warning: tirzepatide caused thyroid C-cell tumors in rodents, and it is contraindicated in patients with a personal or family history of medullary thyroid carcinoma (MTC) or Multiple Endocrine Neoplasia syndrome type 2 (MEN 2) (FDA Mounjaro label).
  • Gastrointestinal adverse events (nausea, diarrhea, vomiting, constipation, decreased appetite) are the most commonly reported effects in clinical trials and FAERS pharmacovigilance data.
  • Labeling and pharmacovigilance note risks including acute pancreatitis, gallbladder/biliary disease, hypoglycemia (especially with insulin or sulfonylureas), and acute kidney injury secondary to dehydration; hypersensitivity reactions have been reported.
  • Material sold outside a licensed pharmacy supply chain (e.g. 'research' or compounded vials) is unregulated and may differ in identity, purity, or concentration from the approved product.
References