Peptide Profile
Tesamorelin
Growth Hormone-Releasing Hormone (GHRH) Analog
CLINICAL DEVELOPMENT STAGE:
Approved
Tesamorelin is a synthetic analog of growth hormone-releasing hormone (GHRH) that activates GHRH receptors and stimulates endogenous growth hormone and IGF-1 signaling. It has been studied extensively for its effects on visceral adipose tissue and metabolic regulation.
Compound Overview
Molecular Formula
C₂₂₁H₃₆₆N₇₂O₆₇S
Molecular Weight
5,135.9 g/mol
CAS Number
218949-48-5
Classification
Growth Hormone-Releasing Hormone (GHRH) Analog
Regulatory Status
FDA APPROVED
Targets / Receptors
Growth Hormone-Releasing Hormone Receptor (GHRHR / GRF receptor)
Research Focus
Growth hormone signaling; GHRH receptor activation; visceral adipose tissue regulation; GH/IGF-1 axis; lipid metabolism; body composition; hepatic fat metabolism
Mechanism of Action
Tesamorelin acts as an agonist of the growth hormone-releasing hormone receptor (GHRHR). It binds and stimulates human GHRH/GRF receptors with activity similar to endogenous growth hormone-releasing hormone, promoting endogenous growth hormone secretion and subsequently increasing insulin-like growth factor 1 (IGF-1).
Unlike administering exogenous growth hormone directly, tesamorelin works upstream through the hypothalamic-pituitary growth hormone signaling pathway. Its structural modification helps distinguish it from native GHRH while retaining receptor activity.
Research Evidence
Tesamorelin has been evaluated extensively in human clinical studies, particularly in adults with HIV-associated lipodystrophy and excess visceral abdominal fat. A randomized trial involving more than 400 participants found significant reductions in visceral adipose tissue compared with placebo, with related changes in waist measurements and triglycerides.
A separate 12-month study found visceral adipose tissue reductions during continued tesamorelin exposure, while participants switched from tesamorelin to placebo lost much of the earlier improvement.
Research has also examined hepatic fat. A randomized trial found reductions in both visceral and liver fat over six months, while a later 12-month study in people with HIV and nonalcoholic fatty liver disease reported a greater reduction in hepatic fat fraction compared with placebo. These liver-related findings represent an additional area of research and should not be interpreted as an FDA-approved indication for liver disease.
Tesamorelin received initial U.S. approval in 2010. Current FDA labeling indicates EGRIFTA WR for reduction of excess abdominal fat in HIV-infected adults with lipodystrophy and specifically states that it is not indicated for weight-loss management.
Safety & Limitations
Clinical findings involving tesamorelin come primarily from defined patient populations, particularly adults with HIV-associated lipodystrophy, and should not automatically be generalized to other populations or research questions.
Because tesamorelin stimulates endogenous GH production and raises IGF-1, the FDA prescribing information identifies several clinically relevant considerations, including elevated IGF-1, fluid retention, glucose intolerance or diabetes, hypersensitivity reactions, and malignancy-related precautions. The label also notes that long-term cardiovascular safety has not been established.
The FDA-approved indication for tesamorelin is specifically reduction of excess abdominal fat in HIV-infected adults with lipodystrophy. It is not FDA-approved as a general weight-loss treatment, and findings involving hepatic fat remain an area of clinical research rather than an approved indication.
Key References
- FDA. EGRIFTA WR (tesamorelin) Prescribing Information. Revised March 2025. FDA prescribing information
- PubChem. Tesamorelin, CID 16137828. National Center for Biotechnology Information. PubChem Tesamorelin record
- Falutz J, et al. Metabolic Effects of a Growth Hormone-Releasing Factor in Patients with HIV. New England Journal of Medicine. 2007.
- Falutz J, et al. Effects of tesamorelin, a growth hormone-releasing factor, in HIV-infected patients with abdominal fat accumulation. Journal of Clinical Endocrinology & Metabolism. 2010.
- Stanley TL, et al. Effects of tesamorelin on non-alcoholic fatty liver disease in HIV. Lancet HIV. 2019.
Last scientifically reviewed: August 27, 2026
