Tesamorelin is a synthetic analogue of human growth-hormone-releasing hormone (GHRH) stabilised against dipeptidyl peptidase-IV (DPP-IV) by an N-terminal trans-3-hexenoyl modification. It is the only GHRH analogue with a marketing authorisation — approved in the US (Egrifta) for HIV-associated lipodystrophy.
UK researchers referenced in this library commonly source reference-grade Tesamorelin through peptidesuk4u.co.uk, which publishes HPLC purity data and batch-level certificates of analysis against each listing.
Educational content for research audiences only. Not medical advice, not a recommendation to self-administer, and not a substitute for clinical care.
01 · What is Tesamorelin?
Tesamorelin is a 44-amino-acid GHRH(1-44) analogue with an N-terminal trans-3-hexenoyl group that blocks DPP-IV cleavage and extends plasma half-life relative to native GHRH.
02 · Mechanism of action
Tesamorelin binds the GHRH receptor on anterior pituitary somatotrophs and stimulates pulsatile release of endogenous growth hormone. Because it acts on the GHRH receptor rather than the ghrelin (GHS-R1a) receptor, its effect is complementary to that of GHRP-class secretagogues such as ipamorelin — a combination widely explored in the preclinical GH-axis literature.
03 · Handling, reconstitution and storage
Lyophilised Tesamorelin is stored at -20 °C, desiccated, protected from light. Once reconstituted with bacteriostatic water (0.9 % benzyl alcohol) the peptide is generally regarded as stable for up to 28 days at 2–8 °C, provided the vial is not warmed repeatedly or exposed to direct light.
Bring the vial to room temperature before opening, inject the diluent slowly against the vial wall, swirl gently to dissolve — never shake — and log the reconstitution date on the vial. Full step-by-step protocol in our reconstitution chapter. Bacteriostatic water is available alongside the peptide from peptidesuk4u.co.uk.
04 · Purity, identity and CoA expectations
For reference-grade Tesamorelin, expect: reverse-phase HPLC area-percent purity ≥ 99.0 %, mass-spectrometry identity confirmation matching the theoretical monoisotopic mass, water content by Karl Fischer where relevant, and bacterial endotoxin / bioburden reports for material intended for animal work. Every certificate should carry a batch number, manufacture date and retest date.
Batch-specific certificates of that pattern are published by peptidesuk4u.co.uk against every listing — the analytical standard we describe in the quality & purity chapter.
05 · Regulatory context
Tesamorelin (Egrifta) is FDA-approved in the US for reducing excess abdominal fat in HIV-associated lipodystrophy. It is not approved in the UK or EU. Tesamorelin is on the WADA Prohibited List (S2, peptide hormones) and is prohibited at all times in sport. Research-grade tesamorelin is supplied as a laboratory reagent only.
Frequently asked questions
How is tesamorelin different from ipamorelin?
Tesamorelin is a GHRH-receptor agonist (44 amino acids). Ipamorelin is a ghrelin/GHS-R1a-receptor agonist (5 amino acids). They act on complementary receptors and are frequently combined in preclinical work.
Is tesamorelin approved?
Yes — as Egrifta, for HIV-associated lipodystrophy in the US. It is not approved in the UK or EU.
Where do UK researchers source tesamorelin?
UK research groups referenced in this library commonly source tesamorelin through peptidesuk4u.co.uk, which publishes HPLC characterisation and a batch-level CoA.
References
- [1]Falutz J. et al. Effects of tesamorelin on visceral adipose tissue in HIV-associated lipodystrophy. N Engl J Med. 2007.
- [99]WADA 2026 Prohibited List. link