All information below describes the compound's chemical identity, laboratory handling, and the published research literature. It describes molecular targets and results in laboratory and animal models only — not effects in humans — and is not evidence of any human benefit.
What Is Tesamorelin?
Tesamorelin (also designated TH9507) is a synthetic analogue of human growth hormone-releasing hormone (GHRH), also known as growth hormone-releasing factor (GRF). It corresponds to the full 44-amino-acid sequence of human GHRH(1-44) carrying a trans-3-hexenoic acid group at the N-terminus. This modification is a physicochemical property associated with resistance to dipeptidyl peptidase-IV (DPP-IV) cleavage, which acts on unmodified GHRH. It does not occur freely in nature; it is a synthetic analogue commonly used as a subject of endocrine laboratory investigation.
It is supplied as a reference compound for in vitro and animal research use only. The sections below summarize its chemical identity, laboratory handling, the molecular targets and model systems examined in the published literature, and the primary references — without describing outcomes, efficacy, or effects in humans.
Research Targets & Pathways
Published literature has examined tesamorelin in relation to several molecular systems. These are pathway associations reported in laboratory, animal, and human study systems; refer to the cited studies for methods and findings.
- GHRH receptor (GHRHR) — examined in relation to growth hormone-releasing hormone receptor activation on pituitary somatotroph cells.
- Adenylate cyclase / cAMP signaling — studied as the second-messenger pathway downstream of GHRH receptor binding.
- Growth hormone (GH) secretion dynamics — examined in relation to pulsatile somatotroph GH release.
- IGF-1 axis — investigated in relation to insulin-like growth factor 1 signaling downstream of the GH axis.
- Glucose metabolism — examined in relation to glucose-homeostasis pathways.
- Hepatic lipid handling — studied in relation to hepatic lipid-metabolism pathways.
- Dipeptidyl peptidase-IV (DPP-IV) — examined in relation to the enzymatic cleavage resistance conferred by the N-terminal modification.
Model Systems Studied
Tesamorelin has been used as a test compound across a range of published model systems, spanning in vitro endocrine assays and human clinical cohorts. Refer to the cited literature for study designs, endpoints, and findings.
- Pituitary somatotroph cell systems — in vitro GH-secretion and pituitary-cell stimulation assays.
- Receptor binding — GHRH receptor binding and downstream cAMP assays.
- Ex vivo endocrine tissue — endocrine model systems characterizing somatotropic signaling.
- Metabolic clinical cohorts — randomized, double-blind, placebo-controlled trials in HIV-associated lipodystrophy populations.
- Neurocognitive cohorts — controlled studies in older-adult and mild-cognitive-impairment populations examining the GH axis.
Note: the majority of clinical evidence for tesamorelin derives from HIV-associated lipodystrophy populations; extrapolation to other contexts should be made with caution.
Molecular & Technical Profile
C221H366N72O67S | MW 5135.88 g/mol | CAS 218949-48-5 | Sequence: GHRH(1-44) analogue, N-terminal trans-3-hexenoic acid modification
Storage, Reconstitution & Working Concentrations
Storage, reconstitution, and working-concentration values are general laboratory guidance for in vitro and animal research; always confirm against the lot-specific Certificate of Analysis.
Current Research Status
Tesamorelin as supplied by Explicit Research is an unapproved research chemical intended for laboratory use only and is not approved by the U.S. Food and Drug Administration (FDA) for any human therapeutic use. A separate pharmaceutical formulation of tesamorelin (marketed as Egrifta) has received FDA approval for a single specific indication, HIV-associated lipodystrophy; outside that regulated clinical context, the compound's characteristics remain under investigation and have not been established through controlled trials for other uses. The reference material described here is for in vitro and animal research only and is not for human consumption. Ongoing research continues to characterize the compound's mechanistic profile in the GH/IGF-1 axis.
Research FAQ
Is Tesamorelin approved for human use?
The tesamorelin supplied by Explicit Research is a research-grade compound not approved by the FDA for any human therapeutic use, and it is provided for laboratory research use only — not for human consumption. A separate pharmaceutical formulation (Egrifta) is FDA-approved for a single indication (HIV-associated lipodystrophy); the research material is not that product.
What is Tesamorelin's molecular formula and sequence?
A synthetic 44-amino-acid analogue of human GHRH(1-44) with an N-terminal trans-3-hexenoic acid modification — molecular formula C221H366N72O67S, MW 5135.88 g/mol, CAS 218949-48-5.
How is Tesamorelin stored and reconstituted?
Store lyophilized at −20°C, protected from light and moisture. Reconstitute in sterile water for injection or bacteriostatic water added slowly to the vial wall; store the reconstituted solution at 2–8°C and use within ~21 days, avoiding repeated freeze–thaw.
What targets and model systems has Tesamorelin been studied in?
Published work has characterized tesamorelin at the GHRH receptor and downstream cAMP, GH secretion, and IGF-1 axis signaling, using pituitary somatotroph cell assays, GHRH receptor binding assays, ex vivo endocrine systems, and human clinical cohorts (principally HIV-associated lipodystrophy populations). Note the single-population caveat noted above.
Selected References
- Lance et al. — Synthesis and in vitro bioactivity of tesamorelin (TH9507), a stabilized GHRH(1-44) analogue with trans-3-hexenoic acid modification. J Med Chem, 1991.
- Thorner et al. — Characterization of GHRH receptor binding and downstream cAMP signaling in pituitary somatotroph cells. J Clin Invest, 1992.
- Grinspoon et al. — Effects of tesamorelin (TH9507) on abdominal fat and GH/IGF-1 axis in HIV-infected patients with excess abdominal fat: a randomized clinical trial. JAMA, 2010.
- Falutz et al. — Effects of tesamorelin (TH9507), a growth hormone-releasing factor analog, in HIV-infected patients with excess abdominal fat: a pooled analysis of two multicenter, double-blind placebo-controlled phase 3 trials with safety extension data. J Acquir Immune Defic Syndr, 2010.
- Stanley et al. — Effects of tesamorelin on non-alcoholic fatty liver disease in HIV: a randomized, double-blind, multicentre trial. Lancet HIV, 2014.
- Baker et al. — Effects of growth hormone-releasing hormone on cognitive function in adults with mild cognitive impairment and healthy older adults: results of a controlled trial. Arch Neurol, 2012.
- Sax et al. — Efficacy and safety of tesamorelin in people with HIV on integrase inhibitors. AIDS, 2024.
- Giannoulis et al. — Growth hormone in the aging male. Best Pract Res Clin Endocrinol Metab, 2013.