Semaglutide vs Tirzepatide vs Retatrutide
Semaglutide
Tirzepatide
Retatrutide
Three lipidated peptide analogs, distinguished by receptor breadth
- Semaglutide is a GLP-1 receptor mono-agonist with a 31-residue peptide chain.
- Tirzepatide is a GIP and GLP-1 receptor dual agonist with a 39-residue peptide chain.
- Retatrutide is a GIP, GLP-1, and glucagon receptor tri-agonist with a 39-residue peptide chain.
Comparison table
| Characteristic | Semaglutide | Tirzepatide | Retatrutide |
|---|---|---|---|
| Receptor classification | GLP-1 mono-agonist | GIP and GLP-1 dual agonist | GIP, GLP-1, and glucagon tri-agonist |
| Peptide family | Glucagon-superfamily analog | Glucagon-superfamily analog | Glucagon-superfamily analog |
| Peptide structure | Linear synthetic peptide | Linear synthetic peptide | Linear synthetic peptide |
| Reported chain length | 31 amino acid residues | 39 amino acid residues | 39 amino acid residues |
| Lipidation | Present | Present | Present |
| General research format | Lyophilized peptide powder | Lyophilized peptide powder | Lyophilized peptide powder |
| Common identity methods | HPLC and mass spectrometry | HPLC and mass spectrometry | HPLC and mass spectrometry |
What is the main difference between the three?
Semaglutide
Tirzepatide
Retatrutide
Receptor classification by compound
Semaglutide: GLP-1 mono-agonist
Tirzepatide: GIP and GLP-1 dual agonist
Retatrutide: GIP, GLP-1, and glucagon tri-agonist
Peptide class and backbone structure
Chain length comparison
Lipidation and conjugate chemistry
Linker architecture may include
- A gamma-glutamate unit
- Short hydrophilic spacer groups
- A fatty diacid or related lipid moiety
- A lysine residue serving as the conjugation site
Amino acid engineering
Molecular profile comparison
Why lot-specific documentation matters
- Certificate of analysis
- Chromatographic purity results
- Observed molecular mass
- Counterion or salt information
- Mass spectrometry data
- Molecular formula
- Monoisotopic mass
- Water or solvent content
Physical format and analytical identification
Reversed-phase high-performance liquid chromatography
Mass spectrometry
Additional characterization
Shared features and key differences
Shared structural features
- They are synthetic peptide analogs.
- They belong to the glucagon-superfamily design space.
- They use linear peptide backbones.
- They contain engineered amino acid substitutions.
- They incorporate lipid conjugation.
- They are commonly evaluated using HPLC and mass spectrometry.
- They are frequently supplied in lyophilized research formats.