Tesamorelin vs sermorelin: what the records compare

How do tesamorelin and sermorelin differ?

Tesamorelin is the full 44-amino-acid human growth-hormone-releasing factor sequence with a hexenoyl group added at one end (Egrifta SV label, section 11). Sermorelin is GRF 1-29, the first 29 amino acids of that sequence (Dominikowski et al., Frontiers in Endocrinology, 2026). The Egrifta SV label reports a tesamorelin half-life of 8 minutes in healthy subjects, with no participant number given in that section (Egrifta SV label, section 12.3), and the records reviewed do not support a like-for-like pharmacokinetic comparison with sermorelin.

Their regulatory records differ more than their chemistry. The Egrifta SV label lists tesamorelin's indication as the reduction of excess abdominal fat in adults with HIV and lipodystrophy, and gives 2010 as the year of initial US approval (section 1). Sermorelin was sold as Geref, approved in 1990 for evaluating pituitary function and in 1997 for children with idiopathic growth hormone deficiency. Its maker notified the FDA in 2008 that the products were being discontinued, and the FDA withdrew the approvals effective 18 June 2009 (FDA, Federal Register notice of 4 March 2013).

That same 2013 notice records the FDA's determination that Geref was not withdrawn from sale for reasons of safety or effectiveness. The 2026 narrative review reads this as supporting a non-clinical explanation, such as commercial or availability decisions, rather than a new safety signal (Dominikowski et al., 2026). The table below sets the two records side by side.

Evidence limits

What do these comparisons not show?

The evidence grades come from one 2026 narrative review, not from a regulator, and the authors say the evidence base for these peptides is highly uneven and should not be interpreted as a unified body of human efficacy data (Dominikowski et al., 2026).

Is tesamorelin or sermorelin more effective?

No head-to-head study was reported in the sources read. A PubMed search of titles and abstracts for both names on 14 October 2026 returned 13 records, four reviews and nine laboratory detection methods, and none reports a comparison of the two in people. In a trial of 412 adults with HIV, visceral fat fell 15.2% with tesamorelin and rose 5.0% with placebo over 26 weeks, a result for that group only (Falutz et al., New England Journal of Medicine, 2007). Sermorelin's approvals were for evaluating pituitary function and for children with growth hormone deficiency, in different people (Federal Register, 4 March 2013), so the two results cannot be set side by side.

The 2026 narrative review makes a related point about indirect evidence. It says claims about CJC-1295 without DAC rest on extrapolation rather than direct human data (Dominikowski et al., Frontiers in Endocrinology, 2026). One molecule standing in for another is not a comparison.

The study findings page lists the tesamorelin trials one by one, with their size, length and limits.

Is any peptide shown to be better than tesamorelin?

The sources read did not include a head-to-head trial showing any peptide to be better than tesamorelin. Published records rank peptides by the quality of their evidence instead. A 2026 narrative review of growth-hormone-axis peptides put tesamorelin in its top tier (A), defined as randomised trial evidence within an approved indication, and gave sermorelin the same tier with a note (A) for its historical approval. Most other GHRH analogues and ghrelin-mimetic secretagogues sat in a middle tier (B) with phase I and II studies, and CJC-1295 without DAC sat in the bottom tier (D) with no peer-reviewed human studies, by the review's own grading (Dominikowski et al., Frontiers in Endocrinology, 2026).

A tier describes how much human evidence exists, not how well a peptide works. A peptide with no trials sits at the bottom because the review found no peer-reviewed human studies of it, not because it was measured and found weak. The reverse holds too: a top tier means trials exist, and their results cover only the people and outcomes they tested.

For the safety side of tesamorelin's record, the side-effects page reports the label's adverse-event counts.

How does hexarelin compare with tesamorelin in the records?

Hexarelin and tesamorelin sit in different classes in the 2026 narrative review. Tesamorelin is a GHRH analogue. Hexarelin is a growth-hormone-releasing peptide, a secretagogue that the review groups with the ghrelin-mimetic peptides. The review places hexarelin in its middle evidence tier (B), from phase I and II studies in paediatric growth hormone deficiency and adult endocrine populations, with no body-composition trials (Dominikowski et al., Frontiers in Endocrinology, 2026). Tesamorelin sits in the top tier. No head-to-head study was reported in the sources read, so neither can be called better.

The WADA 2026 Prohibited List names both molecules in class S2.2.4: tesamorelin under GHRH analogues, and examorelin (hexarelin) under GH-releasing peptides (WADA, 2026 Prohibited List, effective 1 January 2026).

Is tesamorelin a steroid or a peptide?

Tesamorelin is a peptide. The FDA label describes it as the 44-amino-acid sequence of human growth-hormone-releasing factor with a hexenoyl group, and a chain of amino acids is a peptide (Egrifta SV label, section 11). Steroids such as testosterone are built on a different chemical frame of four joined carbon rings. The World Anti-Doping Agency keeps them apart: anabolic androgenic steroids sit in class S1.1 of its 2026 Prohibited List, and tesamorelin sits in S2.2.4 among peptide hormones and their releasing factors (WADA, 2026 Prohibited List).

The word steroid is sometimes used loosely for any compound that changes body shape. That is a habit of speech, not a chemical fact. Sport rules list both families, under separate headings.

What did trials find after about three months of tesamorelin?

There is no single typical result, but two 12-week placebo-controlled trials report what happened. In a trial of 61 adults with HIV, trunk fat changed by -9.2% in the top tesamorelin group against +0.8% on placebo, while visceral fat changed by -15.7% against -5.4%, a gap that was not statistically significant, in that small trial only (Falutz et al., AIDS, 2005). In a trial of 53 adults with type 2 diabetes, sponsored by the maker of the product, insulin response and diabetes control did not differ significantly between groups over 12 weeks, in that group only (Clemmons et al., PLoS ONE, 2017).

IGF-1 rose 65% in the top tesamorelin group of the 61 adults with HIV in the 12-week trial, in that small 12-week trial only (Falutz et al., AIDS, 2005). In the trial of 53 adults with type 2 diabetes, designed to check glucose safety, total cholesterol was 0.3 mmol/L lower from baseline in the higher tesamorelin group than in placebo according to the abstract, in that small 12-week trial only (Clemmons et al., PLoS ONE, 2017).

The pivotal trials ran more than twice as long. In those two trials of 412 and 404 adults with HIV, visceral fat changed by -15.2% against +5.0% in one and -10.9% against -0.6% in the other, in those groups only (Falutz et al., New England Journal of Medicine, 2007; Falutz et al., Journal of Acquired Immune Deficiency Syndromes, 2010).

Is tesamorelin similar to Ozempic?

No. The two medicines have different listed indications and different receptor descriptions in their labels. The Ozempic label (DailyMed record, updated 1 June 2026, read 14 October 2026) describes semaglutide as a GLP-1 analogue with 94% sequence homology to human GLP-1, a GLP-1 receptor agonist whose listed indications include glycaemic control in adults with type 2 diabetes as an adjunct to diet and exercise (sections 1 and 12.1). The Egrifta SV label reports that tesamorelin binds GHRH receptors in laboratory tests, an in-vitro observation that does not itself establish a clinical outcome (Egrifta SV label, section 12.1), and states that it is not indicated for weight loss management (section 1).

Both are peptide medicines, which is where the likeness ends. One copies the hormone GLP-1, which acts on insulin and glucagon, and the other copies a brain signal that releases growth hormone. In the two pivotal trials of adults with HIV (273 on tesamorelin and 137 on placebo in the first, 270 and 126 in the second), mean weight changed by -0.4 kg against 0.0 kg in the first trial and +0.5 kg against +0.3 kg in the second, with confidence intervals for the differences that included zero, for those groups only (Egrifta SV label, Table 3). The study findings page covers the weight results.

Research-use reference material of either molecule is a separate thing from the approved medicine, and the final section below says why.

Is research-use tesamorelin the same as the approved medicine?

No. The molecule is the same on paper, but the product is not. Egrifta SV is an FDA-approved medicine with a label and trial data behind it. Research-use tesamorelin reference material is a laboratory compound, is not a medicine, is not a substitute for one, and is not for human or animal use. Nothing on this page, including the trial results, should be read as a statement about any laboratory material, and the same holds for sermorelin and for hexarelin.

This site's catalogue lists tesamorelin reference material as freeze-dried laboratory stock with a historical sample report that covers only the sample it names. The legal status page sets out the Australian regulatory records for the medicine.