Tesamorelin Peptide: what the research shows
Tesamorelin peptide is a synthetic analog of growth hormone-releasing hormone (GHRH). It signals the pituitary to release growth hormone. Published trials studied abdominal fat in adults with HIV. Those findings do not establish benefits in healthy adults. PeptidesDirect supplies research material, not the approved medicine.
Specifications
| Sequence length | 44 amino acids (modified GHRH 1-44) |
|---|---|
| CAS number | 218949-48-5 |
| Molecular weight | 5135.83 g/mol |
| Purity | ≥98% (HPLC) |
| Form | Lyophilised powder |
| Receptor target | GHRH receptor (pituitary) |
What is tesamorelin?
Tesamorelin is a 44-amino-acid GHRH analog. A secretagogue is a compound that prompts a cell to release a substance. Here, that substance is growth hormone (GH). Tesamorelin signals the pituitary rather than supplying GH directly. GH then influences insulin-like growth factor 1 (IGF-1), a downstream signal.
A trans-3-hexenoyl group modifies the start of the peptide chain. This helps slow breakdown by the enzyme dipeptidyl peptidase-4. The modification distinguishes tesamorelin from native GHRH(1-44).
The GHRH receptor pathway
Tesamorelin binds the GHRH receptor on somatotrophs, the pituitary cells that release GH. Binding increases cAMP, a signal inside the cell. This triggers release of stored GH. Release occurs in pulses. Somatostatin and IGF-1 feedback also influence the response.
The receptor pathway matters when comparing compounds. A GHRH analog acts upstream of GH release. Recombinant GH supplies the hormone itself. A shared GH measurement does not make these approaches equivalent.
What the randomised trials established
Falutz et al. (2007) studied adults with HIV and abdominal fat accumulation in a 26-week randomised trial. Tesamorelin reduced visceral adipose tissue compared with placebo. Visceral fat surrounds organs inside the abdomen. It differs from fat beneath the skin. The trial concerned a specific clinical population, not general weight loss.
Stanley et al. (2014) later studied adults with HIV and abdominal fat accumulation. Their randomised trial reported reductions in visceral fat and liver fat. These findings support further research in that setting. They do not establish that a catalog vial is equivalent to the study medicine.
- Population studied: adults with HIV-associated abdominal fat accumulation — not a general population.
- Primary measures: imaging-based visceral adipose tissue and, in later work, hepatic fat fraction.
- Mechanistic readouts: GH and IGF-1 concentrations.
Longer-term and secondary findings
Falutz et al. (2008) examined longer-term effects and safety. The study compared continued exposure with withdrawal. Visceral fat reduction was not maintained after exposure stopped. The result limits claims about lasting effects.
Fourman et al. (2017) linked visceral fat reduction with improved liver enzyme measures. This was an association within a defined patient population. It does not prove the same effect in other groups.
What has not been established
The trials cited here concern adults with HIV-associated abdominal fat accumulation. They measured specific imaging and laboratory outcomes. They do not establish benefits in healthy adults or athletic settings. Nor do they establish outcomes that the studies did not measure.
Keep each finding attached to its study population and material. State what your model tests. Do not borrow a clinical conclusion for a different experiment.
Interpreting the evidence in laboratory research
For laboratory research, first check whether the model expresses the relevant receptor. GH release is episodic, so a single measurement can miss a pulse. Serial measurements may give a fuller picture. IGF-1 measures a downstream response, not GH release itself.
Ipamorelin acts on the ghrelin receptor, not the GHRH receptor. Compare receptor activity as well as GH measurements. Evidence for either component does not validate a commercial blend.
Handling in the lab
Keep lyophilised material cold, dry and protected from light. Follow the documented storage conditions and your laboratory protocol. Record the lot and preparation date. Check solvent compatibility and stability for the assay rather than assuming one preparation suits every experiment.
Frequently asked questions
What is tesamorelin peptide?
A synthetic 44-amino-acid GHRH analog that stimulates the pituitary to release growth hormone. It has been studied in randomised clinical trials in HIV-associated abdominal fat accumulation.
How does tesamorelin work?
It binds GHRH receptors on pituitary cells. This raises the cell signal cAMP and triggers GH release. Feedback signals also influence the response.
Is tesamorelin the same as growth hormone?
No. Recombinant growth hormone supplies GH directly; tesamorelin signals the pituitary to release its own GH. The two have different mechanisms and different published evidence bases.
What does the hexenoyl group on tesamorelin do?
The trans-3-hexenoyl group on the N-terminus slows enzymatic breakdown by dipeptidyl peptidase-4, so the analog persists longer than native GHRH(1-44).
What did the tesamorelin clinical trials measure?
The trials measured visceral fat by imaging in adults with HIV-associated abdominal fat accumulation. Later work also measured liver fat and GH/IGF-1 concentrations.
Does the effect persist after tesamorelin is stopped?
The longer-term published data indicate the visceral fat reduction is not maintained once administration stops (Falutz et al., 2008).
Has tesamorelin been studied in healthy adults?
The randomised evidence cited here is in a specific clinical population. Effects in healthy adults or in body-composition settings have not been established by those trials.
How is tesamorelin different from ipamorelin?
Tesamorelin acts on the GHRH receptor; ipamorelin is a five-amino-acid peptide that acts on the ghrelin (GHS-R1a) receptor. They reach GH release through two different receptors.
Why is tesamorelin sold as a blend with ipamorelin?
Because the two act on separate receptors, researchers study GHRH analogs and ghrelin mimetics together. No controlled study of the commercial blend itself is cited here.
Product pages: Tesamorelin 5mg / 10mg · Tesamorelin + Ipamorelin blend
What should be measured in tesamorelin research?
GH release occurs in pulses. Serial sampling or an integrated measure can be more informative than one timepoint. IGF-1 is a downstream marker.
How should tesamorelin be stored?
Lyophilised powder should be kept cold, dry and protected from light. Reconstituted solutions should be refrigerated and used within the stability window for your lab protocol.
Where can I buy tesamorelin peptide for research?
Compare the listed 5mg and 10mg options on the Tesamorelin product page. A Tesamorelin + Ipamorelin blend is also listed. These are vial contents, not administration instructions. Check current prices and available documentation before ordering. Read the research peptides guide research peptides guide for supplier-selection context.
Product pages: Tesamorelin 5mg / 10mg · Tesamorelin + Ipamorelin blend
How do I check tesamorelin purity?
Review available documents for the compound and lot. HPLC peak-area purity, measured molecular mass and vial quantity answer different questions. A listed specification is not a measured lot result. Read the purity guide /learn/peptide-purity-guide for details.
Is this product for human use?
No. PeptidesDirect sells this compound for laboratory research only. It is not a drug, food or cosmetic and is not for human or veterinary use. This page summarises published research and is not dosing or medical guidance.
Shop the compounds covered in these FAQs: Tesamorelin 5mg / 10mg · Tesamorelin + Ipamorelin blend
References
- Falutz J, et al. Metabolic effects of a growth hormone-releasing factor in patients with HIV. N Engl J Med. 2007. PubMed 18057338
- Falutz J, et al. Long-term safety and effects of tesamorelin, a growth hormone-releasing factor analogue, in HIV patients with abdominal fat accumulation. AIDS. 2008. PubMed 18690162
- Stanley TL, et al. Effect of tesamorelin on visceral fat and liver fat in HIV-infected patients with abdominal fat accumulation: a randomized clinical trial. JAMA. 2014. PubMed 25038357
- Fourman LT, et al. Visceral fat reduction with tesamorelin is associated with improved liver enzymes in HIV. AIDS. 2017. PubMed 28832410
- Raun K, et al. Ipamorelin, the first selective growth hormone secretagogue. Eur J Endocrinol. 1998. PubMed 9849822
Research compounds
Related guides
- Tesamorelin vs Ipamorelin
- GH peptide comparison
- Research peptides guide
- Reconstitution guide
- Storage guide
Research Use Only. Not for human or veterinary use. Not dosing or medical guidance.
