Tesamorelin — wholesale 10-vial kits

Research context

Where sermorelin trims GHRH to its active 29-residue core, tesamorelin keeps all 44 residues of the native hormone and protects the N-terminus instead. The trans-3-hexenoyl group on tyrosine 1 blocks dipeptidyl peptidase-4, the enzyme that inactivates native GHRH, giving a stabilized agonist at the GHRH receptor.

Origin and molecular design. Tesamorelin was developed by Theratechnologies under the code TH9507. Its non-clinical pharmacology paper (Ferdinandi et al., Basic & Clinical Pharmacology & Toxicology, 2007) describes it as hGRF(1-44)NH₂ minimally modified by the addition of a trans-3-hexenoyl moiety to Tyr1, and reports that the modification made the peptide resistant to dipeptidyl aminopeptidase-IV, slowed its degradation in rat, dog and human plasma in vitro, and prolonged its plasma elimination in vivo. Unlike Mod GRF 1-29, which gains stability through four internal substitutions, tesamorelin leaves the entire native sequence intact and changes only the N-terminal cap, so comparing the two isolates the contribution of N-terminal acylation from that of internal substitution.

In the laboratory, tesamorelin serves as a stabilized full-length GHRH-receptor agonist for pituitary cell models and receptor-signaling assays, and as a comparator when evaluating truncated analogs. It is also a well-characterized reference standard for developing RP-HPLC and LC-MS methods for long peptides, where deamidation and oxidation variants are the main impurities: because the native sequence is retained, Asn8 and Met27 are both present, so the same degradation routes seen with sermorelin apply to it as well. Plasma-stability assays in several species are the standard way its DPP-4 resistance is demonstrated.

U.S. regulatory status: tesamorelin is the active ingredient of an FDA-approved drug product (Egrifta), first approved in November 2010. With 44 amino acids it exceeds the 40-residue threshold in FDA's regulatory definition of a protein (21 CFR 600.3), and Drugs@FDA now lists its application as a biologics license application, BLA 022505. The tesamorelin sold by WholesalePeptide.us is a research reference compound, not that drug product, and is supplied only for in-vitro, analytical and preclinical laboratory research.

For a 44-residue peptide, the COA details that matter most are the related-substance profile on RP-HPLC (deletion sequences, deamidated and oxidized variants) and an LC-MS mass that matches the hexenoylated full-length molecule. Each lot we ship has a COA that reports both, plus net peptide content, so the quantity of active peptide in each vial can be calculated rather than assumed from vial weight.

It is commonly ordered together with sermorelin and Mod GRF 1-29 for GHRH-analog comparison panels, where the three cover the native 29-residue fragment, an internally substituted analog of it, and the N-terminally acylated full-length hormone. Lot-specific COAs for all three let a lab document that panel from one source, and mixed-compound orders count toward the same wholesale tier.

Research areas

• Full-length GHRH receptor agonism
• DPP-4 resistance by N-terminal acylation
• Plasma-stability assays for N-terminally modified peptides
• Pituitary somatotroph cell models
• Analytical methods for 40+ residue peptides

Handling and storage

• Store lyophilized vials at −20 °C, sealed, protected from light and moisture.
• Let the vial reach room temperature before opening to limit condensation on the powder.
• Reconstitute in a sterile buffer appropriate to the assay, following your lab's SOP.
• Aliquot reconstituted material and freeze once; avoid repeated freeze–thaw.