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For research use only.

Tirzepatide

Dual GIP / GLP-1 agonist · often called GLP-2
What it is

Tirzepatide is a lab-made dual agonist at the GIP and GLP-1 receptors, often called GLP-2.[1][2] The nickname doesn’t make it GLP-2, which is a separate hormone made in the gut.[3]

Origin: First described in 2018 by Coskun and colleagues at Eli Lilly in Indianapolis as LY3298176, a fatty-acid-modified peptide built to activate both the GIP and GLP-1 receptors.[1]

What researchers study it for

Research areas

Large human trials and FDA-approved labels point to several research and labeled uses.

  • Blood sugar control in type 2 diabetes, as studied in the SURPASS program and labeled for Mounjaro[2][4]
  • Body-weight reduction in adults with obesity or overweight, as studied in SURMOUNT-1 and related trials and labeled for Zepbound[5][6]
  • Lower risk of major cardiovascular events in adults with type 2 diabetes at high risk, labeled for Mounjaro[2]
  • Moderate to severe obstructive sleep apnea in adults with obesity, labeled for Zepbound[6]
  • Head-to-head weight outcomes versus semaglutide in adults with obesity without type 2 diabetes (SURMOUNT-5)[7]

Evidence level

Level 4 of 4: Large human trialsSURMOUNT-1 randomized 2,539 adults with obesity, FDA based Mounjaro on evidence from thousands of people with type 2 diabetes, and tirzepatide is FDA approved as Mounjaro and Zepbound for labeled uses.[2][4][5][6]

Why so few human trials?

Cautions

Studies and regulators point to several reasons for care.

  • FDA labels carry a boxed warning that tirzepatide caused thyroid C-cell tumors in rats, and it is unknown whether that risk applies in people[2][6]
  • Labels warn about acute pancreatitis, severe gastrointestinal reactions, gallbladder disease, and other serious risks[2][6]
  • The approved brand-name medicines are for specific labeled uses with diet and activity guidance on the labels; research materials are not those medicines[2][4][6]

Tirzepatide is FDA approved as Mounjaro (type 2 diabetes, including cardiovascular risk reduction in high-risk adults) and as Zepbound (chronic weight management and obstructive sleep apnea in adults with obesity), each for the uses on its label.[2][4][6]

Also called

Tirzepatide goes by several names.

  • LY3298176, its early lab code[1]
  • Dual GIP and GLP-1 receptor agonist[2][6]
  • Often called GLP-2 (nickname only; not the gut hormone GLP-2)[3]

Good to know

The approved Mounjaro and Zepbound products are finished medicines reviewed by FDA; a research vial of tirzepatide is not the same as those brand-name products.[2][4][6]

Handling

Storage basics General

These general basics apply to most freeze-dried research peptides.

Most research peptides come as a freeze-dried powder in a sealed vial
Unmixed vials are generally kept cold, dry, and away from light
Mixed solutions are generally refrigerated, since they are less stable than the dry powder
Peptides 101For mixing basicsNPL Dose CalculatorTo work out concentration after mixing
Go deeper

Sources and studies

These studies and official pages are the research behind this profile.

  1. 1LY3298176, a novel dual GIP and GLP-1 receptor agonist for the treatment of type 2 diabetes mellitus: From discovery to clinical proof of conceptCoskun T, et al. (2018) · Molecular Metabolism
  2. 2MOUNJARO (tirzepatide) injection: prescribing informationU.S. Food and Drug Administration (2026) · Drugs@FDA
  3. 3Glucagon-like Peptide-2Estall JL, Drucker DJ (2006) · Annual Review of Nutrition
  4. 4Drug Trials Snapshots: MOUNJAROU.S. Food and Drug Administration (2022)
  5. 5Tirzepatide Once Weekly for the Treatment of ObesityJastreboff AM, et al. (2022) · The New England Journal of Medicine
  6. 6ZEPBOUND (tirzepatide) injection: prescribing informationU.S. Food and Drug Administration (2026) · Drugs@FDA
  7. 7Tirzepatide as Compared with Semaglutide for the Treatment of ObesityAronne LJ, et al. (2025) · The New England Journal of Medicine