← Compare·GLP-1 family
Semaglutide vs Tirzepatide.
Both are long-circulating incretin-receptor peptides, and researchers reach for each by its INN. The difference is structural and specific: semaglutide is a single agonist at the GLP-1 receptor, while tirzepatide is a dual agonist engineered to engage both the GIP and GLP-1 receptors from one molecule. Here is how the two line up on what is actually verifiable — structure, receptor targets, developer, regulatory status, and third-party documentation — not on outcomes.
- Third-party tested
- ILS Laboratories · ISO/IEC 17025
- Lot-specific COA
Side by side — the verifiable facts
- Class
- Semaglutide: GLP-1 receptor agonist
- Tirzepatide: GIP + GLP-1 dual agonist
- Receptor target
- Semaglutide: GLP-1
- Tirzepatide: GIP + GLP-1
- Agonism
- Semaglutide: Single agonist
- Tirzepatide: Dual agonist
- Structure
- Semaglutide: 31-residue GLP-1 analog, C18 fatty-diacid chain
- Tirzepatide: 39-residue synthetic linear peptide
- Developer
- Semaglutide: Novo Nordisk
- Tirzepatide: Eli Lilly
- Regulatory status
- Semaglutide: Approved INN
- Tirzepatide: Approved INN
- Third-party COA
- Semaglutide: ILS Labs · ISO/IEC 17025
- Tirzepatide: ILS Labs · ISO/IEC 17025
- Vendor price
- Semaglutide: $49.99
- Tirzepatide: $59.99 (30MG)
The honest difference
What actually separates them.
The clearest distinction is receptor count: one versus two. Semaglutide is a 31-residue analog of human GLP-1; tirzepatide is a 39-residue synthetic peptide that adds the GIP receptor to the GLP-1 target. Both are FDA-approved INNs, which is exactly why the identity question matters — the published receptor pharmacology describes the clinical molecule, and whether the research-grade compound in a given vial is that same molecule is what a lot-specific third-party COA is for. We link to Amino Club's ILS Laboratories (ISO/IEC 17025) COA library for both. Buy on documentation, not on brand adjacency.
Recommended vendor · Amino Club
Both ship from Amino Club, each with its own lot-specific COA.
- Third-party tested
- ILS Laboratories · ISO/IEC 17025
- Lot-specific COA
Flash sale at Amino Club — up to 50% off select research compounds, through Nov 8. Your purchase is tracked when you land through these links.
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