Tesamorelin

Tesamorelin research peptide in Thailand

Tesamorelin is a stabilised analogue of full-length human growth-hormone-releasing hormone, GHRH(1-44), studied for its effects on pulsatile growth hormone secretion, IGF-1 output, and visceral adipose tissue. It is the only GHRH analogue to have reached regulatory approval (as Egrifta, for HIV-associated lipodystrophy), which means it carries phase 3 human trial data that most research GHRH peptides do not.

Supplied as a lyophilised powder for laboratory research use only. This page summarises the published literature so a researcher can identify the compound; it is not a medicine and gives no administration guidance.

Quick facts

Product

Tesamorelin (TH9507, trade name Egrifta)

Identity

trans-3-hexenoyl-GHRH(1-44), 44-amino-acid GHRH analogue

CAS number

218949-48-5

Molecular weight

~5136 Da (peptide free base, reported)

Intended use

laboratory research use only

How tesamorelin works

Native GHRH is cleaved within minutes by dipeptidyl peptidase-IV, which makes it impractical as a research stimulus. Tesamorelin carries a trans-3-hexenoic acid group on the N-terminus that blocks that cleavage site, extending the circulating half-life to roughly half an hour while leaving receptor binding intact. It engages the GHRH receptor on pituitary somatotrophs and drives growth hormone release in the body's own pulsatile pattern, which in turn raises hepatic IGF-1.

The downstream interest is adipose-tissue selective. Released growth hormone acts on adipocytes through the GH receptor and JAK2-STAT5 signalling, activating hormone-sensitive lipase and raising lipolysis. Visceral fat is more responsive to this pathway than subcutaneous fat, which is the mechanistic account offered for the tissue-specific visceral adipose tissue (VAT) reductions measured by CT in the phase 3 programme. Because the compound amplifies endogenous GHRH signalling rather than supplying exogenous GH, the resulting hormone profile stays feedback-regulated.

Key research findings

• In a 26-week randomised placebo-controlled phase 3 trial of 412 HIV-positive patients with excess abdominal fat, 2 mg daily tesamorelin was associated with a 15.2% decrease in visceral adipose tissue versus a 5.0% increase on placebo, alongside an 81.0% rise in IGF-1 (Falutz et al., NEJM 2007, PMID 18057338).
• A pooled analysis of two phase 3 trials (806 participants) reported a VAT treatment effect of −15.4% at 26 weeks and −17.5% at 52 weeks in the continued-treatment arm, with triglycerides falling 37 mg/dL versus a 6 mg/dL rise on placebo (Falutz et al., J Clin Endocrinol Metab 2010, PMID 20554713).
• Outside the metabolic indication, a 20-week controlled trial in 152 older adults (66 with mild cognitive impairment) reported a favourable effect of GHRH on cognition overall (P=.03), driven mainly by executive function (P=.005), at 1 mg daily (Baker et al., Arch Neurol 2012, PMID 22869065).

Research applications

• Visceral adipose tissue reduction and tissue-selective lipolysis models.
• GH/IGF-1 axis pharmacology using a pulsatile rather than continuous GH stimulus.
• DPP-IV resistance and peptide half-life engineering studies, with native GHRH as the comparator.
• Lipid-profile and cardiometabolic risk-marker research (triglycerides, cholesterol ratios).
• Age-related growth hormone decline and body-composition protocols.
• Neuroendocrine and cognitive-function research following the mild cognitive impairment trial literature.

Dosing in the literature

The phase 3 programme ran these doses over 26–52 weeks. These figures summarise what published trials reported and are provided for literature reference only, not as administration guidance. To model concentrations and volumes for a study, use the peptide calculator.

Reconstitution & storage

Solvent

Bacteriostatic water — the common laboratory choice

Mixing

Add solvent down the vial wall and swirl gently until dissolved; do not shake

Storage

Refrigerate at 2–8 °C after reconstitution

Use within

About 28 days once reconstituted

Freeze / light

Keep lyophilised powder frozen or refrigerated; protect from direct light; avoid repeated freeze–thaw

These are standard laboratory handling conventions, not instructions for use. See bacteriostatic water for the standard diluent. In Thailand's heat and humidity, minimise time at room temperature and keep vials out of direct sun during courier handling.

Selected research

• Metabolic effects of a growth hormone-releasing factor in patients with HIV — New England Journal of Medicine, 2007 (PMID 18057338).
• Effects of tesamorelin (TH9507) in HIV-infected patients with excess abdominal fat: a pooled analysis of two phase 3 trials with safety extension data — Journal of Clinical Endocrinology & Metabolism, 2010 (PMID 20554713).
• Effects of growth hormone-releasing hormone on cognitive function in adults with mild cognitive impairment and healthy older adults — Archives of Neurology, 2012 (PMID 22869065).
• Further indexed literature via PubMed search for tesamorelin.

Related compounds

• CJC-1295 (no DAC) — the closest comparison: a shortened GHRH(1-29) analogue acting at the same receptor, but with a much shorter action and no comparable clinical trial base.
• Ipamorelin — a selective GHRP acting on the ghrelin receptor rather than the GHRH receptor, frequently used as the contrasting secretagogue pathway in GH-axis studies.
• Bacteriostatic water — the standard diluent used to reconstitute lyophilised research peptides.

See also: growth hormone secretagogues compared and more growth-hormone-axis compounds.

Tesamorelin FAQ

Compliance note

Tesamorelin is provided for laboratory research use only. It is not intended for human or veterinary use, and it is not intended to diagnose, treat, cure, or prevent any disease. Trial results described on this page are findings of the specific cited studies, not claims about this product.