Semaglutide vs Tirzepatide
Two incretin receptor agonists with different receptor coverage. This page compares what the molecules are and which receptors they bind. Both are supplied as research material and neither is a medicine.
The difference in one table
| Semaglutide | Tirzepatide | |
|---|---|---|
| Receptor targets | GLP-1 | GLP-1 + GIP |
| Molecule | 31 amino acids, C18 fatty-acid acylation | 39 amino acids, C20 fatty-diacid acylation |
| Plasma half-life | ~7 days | ~5 days |
| Half-life mechanism | Reversible albumin binding | Reversible albumin binding |
| DPP-4 resistance | Aib substitution at position 8 | Aib substitutions at positions 2 and 13 |
| Reference publication | STEP programme, NEJM 2021 | SURMOUNT-1, NEJM 2022 |
| Supplied as | Lyophilised powder | Lyophilised powder |
Why the second receptor matters pharmacologically
GIP and GLP-1 are both incretin receptors, but they are distinct proteins with distinct tissue distribution. GLP-1 receptors are found in pancreatic islets, the gastrointestinal tract and several regions of the central nervous system. GIP receptors are additionally expressed in adipose tissue.
Tirzepatide engages both from a single molecule, which is why it is described as a dual agonist rather than a combination product. Retatrutide extends the same design principle to a third receptor, glucagon, and is discussed on its own product page.
Both molecules resist degradation by dipeptidyl peptidase-4 through aminoisobutyric acid substitutions, and both use fatty-acid acylation to bind albumin reversibly. Those two modifications, not the receptor profile, are what give them half-lives measured in days rather than minutes.
Interactive comparison
| Attribute | BPC-157 | BPC-157 |
|---|---|---|
| Category | Recovery & Repair | Recovery & Repair |
| Mechanism | Pentadecapeptide that modulates NO synthesis, promotes angiogenesis, and activates growth factor receptors. Primarily local-acting when injected. | Pentadecapeptide that modulates NO synthesis, promotes angiogenesis, and activates growth factor receptors. Primarily local-acting when injected. |
| Primary Uses | Tendon/ligament repairGut healingNeuroprotectionAnti-inflammatory | Tendon/ligament repairGut healingNeuroprotectionAnti-inflammatory |
| Half-life | ~30 min (but longer-lasting local effects) | ~30 min (but longer-lasting local effects) |
| Administration | Subcutaneous injection (local or systemic), Intranasal, Oral | Subcutaneous injection (local or systemic), Intranasal, Oral |
| Human Trials | Limited human data | Limited human data |
| Synergies With | TB-500Thymosin Alpha-1NAD+ | TB-500Thymosin Alpha-1NAD+ |
| Typical Dose | 250-500 mcg per injection | 250-500 mcg per injection |
| Storage (Dry) | Lyophilized, room temperature up to 24 months | Lyophilized, room temperature up to 24 months |
| Storage (Reconstituted) | 2-8°C, use within 28 days | 2-8°C, use within 28 days |
Want to calculate doses for these peptides?
Go to Reconstitution CalculatorQuestions
What is the pharmacological difference between semaglutide and tirzepatide?
Semaglutide binds a single receptor, GLP-1. Tirzepatide binds two, GLP-1 and GIP, from one molecule. Both receptors are class B G-protein coupled receptors signalling through cAMP. Tirzepatide has a binding profile biased towards GIP relative to GLP-1.
How do their half-lives compare?
Semaglutide is roughly seven days, tirzepatide roughly five. Both carry a fatty-acid modification that promotes reversible albumin binding and slows renal clearance: a C18 chain on semaglutide, a C20 fatty-diacid on tirzepatide.
What are the reference publications?
For semaglutide the STEP programme (Wilding et al., New England Journal of Medicine, 2021) and for tirzepatide SURMOUNT-1 (Jastreboff et al., New England Journal of Medicine, 2022). Both are trials in supervised clinical settings, not statements about research material.
How are they supplied by Milo-Lab?
Both as lyophilised powder in sealed vials, with a certificate of analysis reporting purity by HPLC and identity by mass spectrometry. Both are research compounds and neither is supplied as a medicine.
Semaglutide and tirzepatide as discussed here are supplied strictly for laboratory research use and not for human administration. Nothing on this page is medical advice or a recommendation for use in humans.