Tesamorelin
Synthetic GHRH analogue consisting of the full 44-amino-acid human GHRH sequence with trans-3-hexenoic acid N-terminal conjugation for DPP-IV resistance. Acts as GHRHR agonist on anterior pituitary somatotrophs to stimulate pulsatile GH release. The pharmaceutical form (Egrifta) holds an FDA clinical approval that provides an extensive clinical pharmacology dataset referenced in preclinical metabolic research; this product is supplied for research use only.
Mechanism of Action
Tesamorelin is a full-length GHRH analogue (44 amino acids) with a trans-3-hexenoic acid moiety conjugated at the N-terminus. This modification specifically addresses the primary pharmacokinetic liability of native GHRH: rapid cleavage by dipeptidyl peptidase IV (DPP-IV) at the Ala2–Asp3 bond, which inactivates the peptide within minutes in plasma. The trans-3-hexenoic acid N-terminal group sterically blocks DPP-IV access to this cleavage site, substantially extending the biological half-life while preserving the GHRH receptor (GHRHR) binding and signalling activity of the full-length peptide.
The mechanism of action at the GHRHR is identical to endogenous GHRH: GHRHR is a Gs-coupled class B GPCR expressed on anterior pituitary somatotrophs. Ligand binding activates Gαs, stimulating adenylyl cyclase to produce cAMP, which activates protein kinase A (PKA). PKA activation drives GH gene transcription and triggers vesicular secretion of stored GH from somatotroph granules. The maintained pulsatile character of GH release is noted as a pharmacologically important feature of tesamorelin compared to exogenous hGH administration, which produces non-pulsatile GH levels.
The downstream mechanism studied in metabolic research — particularly the visceral adipose tissue focus — involves GH receptor activation on visceral adipocytes. GHR agonism in adipocytes stimulates hormone-sensitive lipase (HSL) activity through JAK2/STAT5 signalling and downstream lipolytic enzyme activation, promoting triglyceride hydrolysis and free fatty acid release from visceral fat depots. The pharmaceutical form tesamorelin (Egrifta, Theratechnologies) received FDA approval for a specific clinical indication; that regulatory dataset is referenced in the literature as benchmark metabolic endpoint data for preclinical research. BasedPeps Tesamorelin is supplied strictly for in-vitro and preclinical research use only and is not the approved pharmaceutical product.
Key Research Findings
- Phase 3 clinical trials of the pharmaceutical form (Egrifta) documented visceral-adipose-tissue changes measured by computed tomography in a defined patient population; these published datasets are cited in the preclinical metabolic research literature as reference endpoint data. Falutz et al., New England Journal of Medicine, 2007.
- GHRH receptor agonism and pulsatile GH secretion profiles have been characterised and compared to native GHRH in pharmacokinetic studies, with DPP-IV resistance of the trans-3-hexenoic acid modification quantified in stability studies. Theratechnologies tesamorelin (Egrifta) clinical pharmacology literature.
- DPP-IV resistance of tesamorelin compared to native GHRH has been quantified in published plasma stability studies, confirming that the N-terminal modification effectively blocks the primary cleavage site while preserving receptor binding. Ferdinandi et al., Basic & Clinical Pharmacology & Toxicology, tesamorelin stability literature.
- Secondary metabolic endpoints including triglycerides and the total-to-HDL cholesterol ratio were reported alongside the primary VAT endpoint, documented in the literature as evidence of broader GH-axis metabolic pathway engagement in that clinical model. Falutz et al., Journal of Clinical Endocrinology & Metabolism, 2010 (pooled Phase 3 analysis).
- Preclinical work in rodent models established dose-response relationships for visceral fat reduction via the GH receptor pathway, providing mechanistic underpinning for the clinical findings. Theratechnologies preclinical tesamorelin pharmacology literature.
Citations last reviewed: 1 October 2026
As Supplied by BasedPeps
Researcher FAQ
What is Tesamorelin?
Tesamorelin is a synthetic analogue of GHRH (growth hormone releasing hormone) consisting of the full 44-amino-acid sequence of human GHRH conjugated with trans-3-hexenoic acid at the N-terminus. This modification confers resistance to DPP-IV degradation, extending biological half-life. It acts as a GHRHR agonist on anterior pituitary somatotrophs to stimulate pulsatile GH release.
How does Tesamorelin differ from native GHRH?
Native GHRH(1-44) is rapidly cleaved by DPP-IV at the Ala2–Asp3 bond, with a plasma half-life of a few minutes. Tesamorelin’s trans-3-hexenoic acid N-terminal modification sterically blocks DPP-IV cleavage, substantially extending the active half-life while preserving GHRHR binding and signalling activity. This pharmacokinetic improvement is the primary research and clinical advantage of tesamorelin over native GHRH.
What is GHRHR signalling?
The GHRH receptor (GHRHR) is a Gs-coupled class B GPCR on anterior pituitary somatotrophs. Activation triggers: GHRHR → Gαs → adenylyl cyclase → cAMP elevation → PKA activation → GH gene transcription and vesicular GH release. Released GH acts on peripheral tissues (particularly liver) to stimulate IGF-1 production, and on visceral adipocytes to stimulate lipolysis via hormone-sensitive lipase.
How is Tesamorelin stored and reconstituted?
Supplied as lyophilised powder, stored at −20 °C. Reconstitution in sterile bacteriostatic water is standard. Reconstituted solution stored at 2–8 °C and used within 28 days per experimental protocol.
Does BasedPeps provide purity documentation?
Yes. Every BasedPeps lot includes a third-party Certificate of Analysis documenting HPLC purity (≥99%) and mass spectrometric identity confirmation. Certificates of Analysis are available per batch on request.
View BasedPeps Tesamorelin
Research-grade DPP-IV-resistant GHRH analogue. Third-party HPLC and mass spectrometry verification per lot. Certificate of Analysis available on request. Dispatched from Riga, Latvia within 24 hours.
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