— Research monograph
TZ2
The dual GIP/GLP-1 receptor agonist studied in the SURMOUNT and SURPASS programs.
- Class
- Dual GIP / GLP-1 receptor agonist (synthetic 39-amino-acid peptide)
- Half-life (research)
- ~5 days (preclinical and clinical).
- Origin
- First characterized in the open scientific literature in 2018 (Coskun et al.). FDA-approved for type 2 diabetes (2022) and for chronic weight management (2023), marketed under separate brand names.
- Solubility
- Reconstitutes in bacteriostatic water; clear solution.
What is TZ2?
TZ2 is a synthetic 39-amino-acid peptide engineered to act as a single-molecule dual agonist at the glucose-dependent insulinotropic polypeptide (GIP) receptor and the glucagon-like peptide-1 (GLP-1) receptor. The molecule incorporates a C20 fatty-acid moiety that supports extended duration of action via albumin binding.
TZ2 is a regulated therapeutic compound approved for human use under separate brand names in regulated channels. The Merit Sciences offering is supplied for research use only, not for human or veterinary administration. Researchers must confirm jurisdictional eligibility before procurement.
How does TZ2 work?
Binds and activates both the GIP receptor and the GLP-1 receptor with picomolar affinity. The dual-incretin pharmacology is reported to produce additive effects on insulin secretion and glucagon suppression in preclinical metabolic research models.
What the research shows
- In SURMOUNT-1 (NEJM 2022), a 72-week randomized trial in 2,539 adults with obesity, participants in the highest-dose arm saw a mean body-weight reduction of roughly 20.9% from baseline versus about 3.1% on placebo, the largest effect reported for an incretin agent at the time of publication.
- In SURPASS-2 (NEJM 2021), TZ2 was compared head-to-head against semaglutide 1 mg in type-2-diabetes research; all three TZ2 doses produced greater reductions in HbA1c and body weight than semaglutide in the study population.
- The dual mechanism, simultaneous agonism at the GIP and GLP-1 receptors, is the design feature most cited in the literature as the basis for its effect size relative to single-incretin GLP-1 agonists.
- Gastrointestinal effects (nausea, diarrhea) were the most frequently reported adverse events across the trial program, generally mild to moderate and most common during dose escalation.
Research applications
- Incretin signaling research
- Glucose homeostasis models
- Dual receptor pharmacology
- Body weight regulation studies
- Comparative GLP-1 / GIP agonist work
Form & storage
TZ2 ships as a sealed, lyophilized (freeze-dried) powder. Reconstitutes in bacteriostatic water; clear solution. Store sealed, light-protected, and follow your institution’s handling procedures for research materials.
Frequently asked questions
What is TZ2?
TZ2 is a synthetic dual agonist that activates both the GIP and GLP-1 receptors. It is the compound studied in the SURMOUNT (obesity) and SURPASS (type-2-diabetes) clinical-trial programs. Merit supplies it as a lyophilized research compound for research use only, not for human or veterinary use.
How does TZ2 work?
It is a "dual incretin": a single peptide engineered to activate two gut-hormone receptors at once (GIP and GLP-1). Published trials attribute its effect size relative to single-receptor GLP-1 agonists to this combined mechanism. Mechanistic descriptions here summarize published findings and are not clinical claims.
What did the TZ2 trials show?
In SURMOUNT-1, the highest-dose arm showed a mean body-weight reduction of about 20.9% over 72 weeks versus about 3.1% on placebo. In SURPASS-2, it produced greater HbA1c and weight reductions than semaglutide 1 mg. See the linked SURMOUNT-1 and SURPASS-2 summaries for trial design and full outcomes.
Is Merit TZ2 for human use?
No. It is sold strictly for research use only: not for human or veterinary use, and not for diagnostic or therapeutic use. Every batch is tested before it is listed, and its certificate of analysis documenting ≥99% HPLC purity is published in the COA library.
References
- Coskun T, Sloop KW, Loghin C, et al. Molecular Metabolism, 2018 · PMID 30473097
- Frias JP, Nauck MA, Van J, et al. The Lancet, 2018 · PMID 30293770
- Frias JP, Davies MJ, Rosenstock J, et al. New England Journal of Medicine, 2021 · PMID 34170647
- Jastreboff AM, Aronne LJ, Ahmad NN, et al. New England Journal of Medicine, 2022 · PMID 35658024
For research use only. Not for human or veterinary use. Not FDA-approved. Reference information summarized from published literature — not medical or dosing advice.