Research Comparison

HGH Frag 176-191 vs Tesamorelin

In Short

HGH Frag 176-191 is c-terminal human growth hormone fragment (lipolytic fragment); the optimized tyr-modified analog is aod9604; Tesamorelin is stabilized growth-hormone-releasing hormone analog. Both are supplied as lyophilized powders for laboratory and in-vitro research use only. The table below compares their molecular data, half-life and research focus side by side.

	HGH Frag 176-191	Tesamorelin
Classification	C-terminal human growth hormone fragment (lipolytic fragment); the optimized Tyr-modified analog is AOD9604	Stabilized growth-hormone-releasing hormone analog
Molecular formula	C78H125N23O23S2	C223H370N72O69S
Molecular weight	1817.1 g/mol	5195.91 g/mol
CAS number	66004-57-7	901758-09-6
Research half-life	Reported short circulating half-life on the order of minutes in pharmacokinetic work on the related AOD9604 analog; precise figures vary by route and study.	Short (~26–38 minutes) but resistant to enzymatic degradation
Primary research focus	Lipolysis and fat metabolism research	HIV-associated lipodystrophy and visceral fat reduction
Form	Lyophilized powder	Lyophilized powder
Price from	$50.00	$40.50

HGH Frag 176-191

HGH Fragment 176-191 corresponds to the final 16 amino acids of the human growth hormone molecule, a region associated with the hormone's fat-metabolizing activity. In preclinical research it has been investigated for its ability to stimulate lipolysis and inhibit lipogenesis in adipose tissue while showing little effect on IGF-1 levels, insulin sensitivity, or skeletal growth pathways. This selectivity has made it a subject of interest in metabolic and body-composition research models. Supplied as a lyophilized powder for in-vitro and laboratory research use only; not for human consumption.

Full HGH Frag 176-191 research guide

Tesamorelin

Tesamorelin is a synthetic analogue of growth hormone-releasing hormone (GHRH) consisting of the 44-amino acid human GHRH sequence with a trans-3-hexenoic acid modification at the N-terminus. It acts by binding to GHRH receptors on anterior pituitary somatotroph cells, stimulating pulsatile growth hormone (GH) release while preserving the natural hypothalamic-pituitary feedback axis. Beyond lipodystrophy research, studies published in Annals of Neurology (Baker et al., 2012) suggest tesamorelin may improve cognitive function in older adults with mild cognitive impairment by modulating IGF-1 levels in the central nervous system. Compared to direct GH use, tesamorelin preserves physiological GH pulsatility rather than creating supraphysiological sustained GH levels, which research indicates may reduce the risk of insulin resistance associated with exogenous GH. Additional preclinical work has explored its role in peripheral nerve regeneration models. The lyophilized powder should be stored at controlled room temperature (20-25C) or refrigerated; reconstitute with sterile water and use within 24 hours or refrigerate for up to 14 days. This peptide is studied by endocrinology research labs, HIV metabolism centers, and neuroscience institutions investigating GH-IGF-1 axis modulation.

Full Tesamorelin research guide

Frequently Asked Questions

What is the main difference between HGH Frag 176-191 and Tesamorelin?

HGH Frag 176-191 is classified as c-terminal human growth hormone fragment (lipolytic fragment); the optimized tyr-modified analog is aod9604, while Tesamorelin is stabilized growth-hormone-releasing hormone analog. They are distinct research compounds with different mechanisms — the comparison table above sets out the molecular and pharmacokinetic differences side by side.

Can HGH Frag 176-191 and Tesamorelin be studied together?

Some research protocols evaluate related peptides in combination, and research blends exist. Combination study design depends entirely on the research question and model. Both compounds are supplied for laboratory and in-vitro research use only — not for human use.

Are HGH Frag 176-191 and Tesamorelin legal to buy for research?

Both are sold in the United States as research chemicals for laboratory and in-vitro use only. Neither is FDA-approved for human use. Researchers are responsible for compliance with all applicable regulations.

Buy HGH Frag 176-191

From $50.00 — ≥98% HPLC, COA included.

Buy Tesamorelin

From $40.50 — ≥98% HPLC, COA included.

Research Use Only. This comparison summarizes published research. It is not medical advice. Neither compound is for human consumption or FDA-approved.