GLP-1SM, GLP-2TZ, and GLP-3 RT represent three successive generations of incretin-mimetic research peptides — single, dual, and triple-receptor agonists. Here is the side-by-side comparison of their receptor targets, preclinical profiles, and research contexts.
GLP-1SM (marketed as Sema GLP-1 in research) is a single GLP-1 receptor agonist. GLP-2TZ (Tirz GLP-2 in research) is a dual GLP-1 + GIP receptor agonist. GLP-3 RT (Reta GLP-3 in research) is a triple GLP-1 + GIP + glucagon receptor agonist. Each successive generation engages more metabolic pathways. Preclinical literature generally shows larger magnitude effects on adiposity and glycemic models with each generation, though GLP-3 RT is earlier in the publication cycle.
| Attribute | GLP-1SM (Sema GLP-1) |
GLP-2TZ (Tirz GLP-2) |
GLP-3 RT (Reta GLP-3) |
|---|---|---|---|
| Receptor targets | GLP-1R (mono-agonist) | GLP-1R + GIPR (dual agonist) | GLP-1R + GIPR + GCGR (triple agonist) |
| Primary research focus | Glycemic regulation, adiposity, gastric emptying | Glycemic regulation, adiposity, insulin sensitivity (enhanced vs GLP-1 alone) | Adiposity, lipolysis (glucagon-mediated), hepatic fat |
| Preclinical half-life | ~7 days (fatty acid side chain) | ~5 days | ~6 days |
| Typical research dosing frequency | Once-weekly in animal models | Once-weekly | Once-weekly |
| Literature volume | Very large — 15+ years of GLP-1 agonist research | Substantial and growing — dual agonist literature since ~2018 | Emerging — first publications 2022-2024 |
| Distinguishing feature | Most-cited GLP-1 agonist in the scientific literature | GIP receptor engagement adds insulin-sensitization pathway | Glucagon engagement adds hepatic lipolysis pathway |
| SMART MD sizes | 10mg ($79.98), 20mg ($124.98) | 10mg ($88.98), 30mg ($139.98), 60mg ($196.98) | 10mg, 20mg |
GLP-1SM is a GLP-1 receptor agonist with a fatty acid chain modification that extends its preclinical half-life to approximately one week, enabling once-weekly dosing in research models. Its research literature is the largest of the three compounds by a significant margin, with well-characterized preclinical profiles in rodent models of obesity, insulin resistance, and NAFLD.
GLP-2TZ activates both GLP-1 and GIP (glucose-dependent insulinotropic polypeptide) receptors. In preclinical comparison models, the addition of GIP receptor engagement produces larger magnitude effects on body weight and glucose handling than GLP-1 engagement alone. It is the current most-studied dual-incretin agonist.
GLP-3 RT adds glucagon receptor (GCGR) activation to the GLP-1 + GIP dual agonism of GLP-2TZ. The glucagon arm contributes hepatic lipolysis and energy expenditure pathways. It is the newest of the three compounds in preclinical literature, with most publications emerging from 2022 onward.
Because GLP-3 RT is earlier in the publication cycle, researchers should expect rapidly evolving literature over 2026-2027 as more comparative studies are published.
GLP-1SM is the most-characterized GLP-1 agonist with the deepest literature base. Best for isolating GLP-1R effects or replicating established preclinical protocols.
GLP-2TZ allows isolation of GLP-1 vs GLP-1+GIP contribution when compared to GLP-1SM. Useful for dissecting GIPR-specific signaling in your model.
GLP-3 RT's glucagon arm is specifically relevant for hepatic lipolysis and fatty liver models. Note that literature is earlier-stage; expect rapid evolution through 2026-2027.
All compounds are 99%+ HPLC-verified with lot-specific COAs from three independent U.S. laboratories.
The core difference is receptor coverage. GLP-1SM activates only the GLP-1 receptor. GLP-2TZ activates both the GLP-1 receptor AND the GIP receptor. In preclinical comparison studies, the addition of GIP engagement produces larger magnitude effects on body weight and glucose handling than GLP-1 activation alone. GLP-2TZ is often described as a "twincretin" for this reason.
Early preclinical comparative data suggests GLP-3 RT produces larger magnitude adiposity and hepatic fat signal than GLP-2TZ in rodent models, attributable to the addition of glucagon receptor engagement. However, GLP-3 RT's research literature is earlier-stage (first publications ~2022). Direct head-to-head preclinical comparisons are still emerging. Researchers should consult the most current literature for their specific model.
At SMART MD, "Tirz GLP-2" and "Reta GLP-3" are research product naming conventions referring to the number of receptor targets (GLP-1+GIP = "2 receptors" = GLP-2 label; GLP-1+GIP+GCGR = "3 receptors" = GLP-3 label). These are internal product identifiers — they do not refer to the pharmaceutical compound GLP-2 (glucagon-like peptide 2, a different molecule studied for gut mucosa).
GLP-1SM has by far the largest published literature base, with over 15 years of GLP-1 agonist research and thousands of peer-reviewed publications across preclinical and (separately) clinical contexts. GLP-2TZ's literature has grown substantially since ~2018. GLP-3 RT is newest with publications beginning ~2022, and the literature is expected to expand rapidly over 2026-2027.
Yes. GLP-1SM, GLP-2TZ, and GLP-3 RT are legal to acquire for research purposes in the United States. They are classified as research-use-only compounds — not intended for human consumption in this form. Licensed researchers and physicians may acquire them for preclinical research protocols and practice-of-medicine use.
SMART MD verifies every batch through three independent U.S. laboratories. Each lot receives HPLC purity analysis (99%+ average), mass spectrometry molecular weight confirmation, and LAL endotoxin testing (<5 EU/mg). Lot-specific COAs are publicly verifiable before purchase at smartmdpeptides.com/verify.
Every SMART MD batch verified by three U.S. laboratories — HPLC purity, mass spec identity, LAL endotoxin.