Education
What Is Tesamorelin?
A GHRH analog with a single N-terminal modification that extends serum half-life from minutes to hours — what makes it useful in laboratory research.
Tesamorelin is a 44-amino-acid synthetic analog of growth-hormone-releasing hormone (GHRH). Researchers use it when they need a probe for the GHRH receptor with a kinetic profile longer than native GHRH provides. This article is the entry-level explainer; for the structural detail behind the N-terminal modification, see [Tesamorelin in Endocrine Research](/blog/tesamorelin-endocrine-research).
A modified natural sequence
Native GHRH is a 44-residue peptide produced in the hypothalamus. Tesamorelin is essentially the same sequence with one structural modification: a trans-3-hexenoic acid group attached at the N-terminus. The modification doesn't change which receptor the peptide binds — it stays a GHRH-receptor agonist — but it dramatically changes how long the peptide survives before enzymatic degradation.
Why researchers prefer the modified form
Native GHRH is cleaved by dipeptidyl peptidase-4 (DPP-4) within minutes of entering serum. For most experimental protocols, that's too fast: by the time downstream signaling has been measured, the input signal has already decayed. Tesamorelin resists DPP-4 cleavage thanks to the hexenoic acid modification, extending serum half-life from minutes into a workable laboratory window.
Quality assurance
Identity is confirmed by mass spectrometry — the molecular weight verifies the hexenoic acid modification is present and the sequence is intact. Main-peak purity is quantified by HPLC against related substances and deletion peptides that can arise during synthesis. Both reports are published per batch in the [Certificates repository](/certificates).
What REPRIME's tesamorelin offers
- 20 mg lyophilized powder per vial - Mass-spectrometry-confirmed identity (current batch) - HPLC main-peak purity ≥99% - Unique verification code on every package insert - Public COA for every batch
Verification
Every package has a verification code. The first scan on [/verify](/verify) stamps it as verified; subsequent scans warn that the code has already been used — your anti-counterfeit signal.
Positioning
Tesamorelin is research-grade material for endocrine and growth-hormone-axis studies only. REPRIME does not market it for any non-research application, does not provide dosage or protocol guidance, and does not make any medical claims.
Shop [Tesamorelin](/shop/tesamorelin).