peptidefix

Tirzepatide

Also: Mounjaro, Zepbound, LY3298176

Metabolic & weight

Summary

Tirzepatide is a synthetic peptide that activates two hormone receptors at once: GIP and GLP-1, both involved in insulin release and appetite. It is a licensed medicine in the UK, the US and Australia, which makes it the most heavily regulated substance covered on this site, and it has the largest trial programme of anything here.

What it targets

Acting on the GIP and GLP-1 receptors together influences insulin secretion, appetite and how full a meal feels. In the SURMOUNT-1 trial, 2,539 adults with obesity, or overweight plus a weight-related condition but not diabetes, were randomised to one of three tirzepatide levels or placebo for 72 weeks; both co-primary endpoints, percentage weight change and the proportion losing at least 5 percent of body weight, favoured tirzepatide at every level. A three-year extension followed the participants who also had prediabetes, reporting weight change to week 176, progression to type 2 diabetes and what happened over 17 weeks off treatment. Two further phase 3 trials tested it in moderate-to-severe obstructive sleep apnoea with obesity, measuring breathing interruptions per hour of sleep, and a 731-person trial tested it in heart failure with preserved ejection fraction and obesity against cardiovascular outcomes and quality of life. The programme is funded by the manufacturer throughout.

body weight in obesity (phase 3, 2,539 people)progression to type 2 diabetes (3-year extension)obstructive sleep apnoea with obesity (two phase 3 trials)heart failure with preserved ejection fraction (731 people)

Clinical Research

Tirzepatide Once Weekly for the Treatment of Obesity
Jastreboff AM, Aronne LJ, Ahmad NN, et al. (2022). New England Journal of Medicine. human 2,539 adults with obesity, or overweight with a weight-related complication, excluding diabetes; phase 3, double-blind, placebo-controlled, 72 weeks
Tirzepatide for Obesity Treatment and Diabetes Prevention
Jastreboff AM, le Roux CW, Stefanski A, et al. (2025). New England Journal of Medicine. human 1,032 SURMOUNT-1 participants who had both obesity and prediabetes, followed to 176 weeks plus a 17-week period off treatment
Tirzepatide for the Treatment of Obstructive Sleep Apnea and Obesity
Malhotra A, Grunstein RR, Fietze I, et al. (2024). New England Journal of Medicine. human adults with moderate-to-severe obstructive sleep apnoea and obesity across two phase 3 trials, one in people not using positive airway pressure and one in people already using it; 52 weeks
Tirzepatide for Heart Failure with Preserved Ejection Fraction and Obesity
Packer M, Zile MR, Kramer CM, et al. (2025). New England Journal of Medicine. human 731 patients with heart failure, an ejection fraction of at least 50 percent and obesity; international, double-blind, placebo-controlled, at least 52 weeks

All research on Tirzepatide →

Suppliers stocking Tirzepatide

7 of the 30 listed suppliers. Each row opens its full listing.

American Peptides United States Products are sold for Research Use Only and not for Human Consumption. Not for human or veterinary use. Au Peptide Labs Australia For laboratory research use only. Not for human consumption. Aussie Peptides Australia Research use only. Statements have not been evaluated by the TGA. We do not ship internationally at this time. Next Gen Peptides Australia Not for human consumption. Peak Lab Peptides United States All products on this site are for research and development use only. Products are not for human consumption of any kind. Research Peptide United Kingdom Supplied strictly for research and laboratory use only and not for human or veterinary consumption. Synapse Peptides Australia Australia All products are supplied strictly for research purposes only and are not intended for human or veterinary use.