Sermorelin vs Tesamorelin

Sermorelin and tesamorelin are both synthetic analogues of growth hormone-releasing hormone (GHRH) that stimulate the pituitary to release growth hormone ^1,6. Sermorelin is the 29-amino-acid N-terminal fragment of GHRH; it was FDA-approved as GEREF, and both GEREF applications are now listed as discontinued ^1,4. Tesamorelin is the full 44-amino-acid GHRH sequence with an added hexenoyl group, and it is FDA-approved (first in 2010) for reducing excess abdominal fat in adults with HIV and lipodystrophy ^6. The two were developed for different conditions and have not been compared in a head-to-head trial in the sources reviewed ^1,7.

Sermorelin

Not approved — research use only

Tesamorelin

FDA-approved

Side by side

Field	Sermorelin	Tesamorelin
Class	GHRH analogue ¹	GHRH analogue (growth hormone-releasing factor analogue) ⁶
Origin and structure	29-amino-acid analogue of human GHRH, described as the shortest synthetic peptide with the full biological activity of GHRH ¹	The 44-amino-acid sequence of human GRF with a trans-3-hexenoyl group attached at the N-terminal tyrosine ⁶
Proposed mechanism	Stimulates growth hormone secretion from the anterior pituitary ¹	Binds and stimulates human GRF receptors with potency similar to endogenous GRF, causing pulsatile release of endogenous growth hormone ⁶
Half-life	Disappearance half-time of about 4 minutes for GHRH(1-29)-NH2 during intravenous infusion in 10 healthy men ³	About 11 minutes in healthy subjects after subcutaneous administration, per the US label ⁶
Highest human trial phase	Approved product; pivotal data include a 110-child multicentre open-label study in growth hormone deficiency ^2,4	Approved product; two phase 3 placebo-controlled trials in HIV-associated abdominal fat ^6,8
FDA status	Approved as GEREF (NDA 019863, 1990; NDA 020443, 1997); both listed as discontinued in Drugs@FDA as of 24 October 2026 ^4. In 2013 FDA determined that GEREF was not withdrawn from sale for safety- or efficacy-related reasons ⁵	FDA-approved (initial US approval 2010); EGRIFTA WR label revised 03/2025 ⁶
Published human outcomes	In growth hormone-deficient children, mean height velocity rose over 12 months in an open-label study ^2; a review notes increases were smaller than with somatropin ¹	In a 412-patient phase 3 trial, visceral fat fell by 15.2% versus a 5.0% rise with placebo ^7; a 61-patient trial reported reduced liver fat in HIV with NAFLD ⁹
Safety signals	No adverse biochemical or hormonal changes, and no change in fasting glucose, were reported in the 110-child study ²	Label warnings include neoplasm risk, elevated IGF-1, fluid retention, glucose intolerance, hypersensitivity and increased mortality in acute critical illness ⁶
WADA status	Named under S2.2.4 (GHRH analogues); prohibited at all times (2026 List) ¹¹	Named under S2.2.4 (GHRH analogues); prohibited at all times (2026 List) ¹¹
Who funded the evidence	The paediatric efficacy study was run by the Geref International Study Group ^2; GEREF applications were held by EMD Serono ⁴	Phase 3 registration sponsored by Theratechnologies ^10; later liver-fat trials funded by the US NIH ⁹

Sermorelin: what the data says

Sermorelin was developed for the diagnosis and treatment of idiopathic growth hormone deficiency in children ¹. A review describes intravenous sermorelin as a rapid, relatively specific test of growth hormone secretion, while noting that a normal response cannot exclude deficiency of hypothalamic origin ¹.

In a multicentre open-label study of 110 previously untreated prepubertal children with growth hormone deficiency (humans), mean height velocity increased at 6 and 12 months, and 74% were considered good responders at 6 months ².
The review reports smaller height-velocity increases than with somatropin, with long-term effects on adult height not determined ¹.
In healthy men, GHRH(1-29)-NH2 was cleared rapidly, with a disappearance half-time of about 4 minutes ³.

Tesamorelin: what the data says

Tesamorelin is approved in the US for reducing excess abdominal fat in HIV-infected adults with lipodystrophy; the label states that long-term cardiovascular safety has not been established ⁶.

In a 412-patient randomized phase 3 trial (humans), visceral adipose tissue decreased by 15.2% with tesamorelin and increased by 5.0% with placebo over 26 weeks, while IGF-I rose by 81% ⁷.
A pooled analysis of two phase 3 trials (806 patients) reported a 15.4% treatment effect on visceral fat at 26 weeks, with no significant change in subcutaneous abdominal fat ⁸.
In a 61-patient NIH-funded trial in HIV with non-alcoholic fatty liver disease (humans), hepatic fat fraction fell more with tesamorelin than placebo over 12 months ⁹.

Key research differences

Structure: sermorelin is the 29-residue N-terminal fragment of GHRH ^1, whereas tesamorelin is the full 44-residue sequence with an N-terminal hexenoyl modification ^6.
Current FDA status: tesamorelin is an approved, marketed product ^6; sermorelin's GEREF applications are listed as discontinued, although FDA found they were not withdrawn for safety- or efficacy-related reasons ^4,5.
Approved use: sermorelin was studied for growth hormone deficiency in children ^1,2, whereas tesamorelin is indicated for excess abdominal fat in adults with HIV and lipodystrophy ^6.
Half-life: about 4 minutes for intravenous GHRH(1-29)-NH2 in healthy men ³ versus about 11 minutes for subcutaneous tesamorelin in healthy subjects ^6, measured by different routes and methods.

Where the evidence is limited

No head-to-head trial of sermorelin and tesamorelin was located. Their main trials enrolled different populations (children with growth hormone deficiency versus adults with HIV-associated abdominal fat) and measured different outcomes (height velocity versus visceral fat), so results cannot be compared directly ^2,7. The half-life figures come from different routes and study designs ^3,6. Much of the sermorelin evidence predates modern trial reporting standards ^1,2.

Frequently asked questions

Is sermorelin FDA-approved?

Sermorelin was approved as GEREF, but both GEREF applications are listed as discontinued in Drugs@FDA ^4. In 2013 the FDA determined GEREF was not withdrawn from sale for safety- or efficacy-related reasons ^5.

Is tesamorelin the same as sermorelin?

No. Both are GHRH analogues, but sermorelin is a 29-amino-acid fragment while tesamorelin is the full 44-amino-acid sequence with a hexenoyl group added ^1,6.

Can sermorelin and tesamorelin be compared directly?

Not on current evidence: no head-to-head trial was located, and they were tested in different populations for different outcomes ^2,7.

Are sermorelin and tesamorelin banned in sport?

Yes. WADA's 2026 List names both under S2.2.4 as GHRH analogues, prohibited at all times ^11.

References

Sermorelin: a review of its use in the diagnosis and treatment of children with idiopathic growth hormone deficiency BioDrugs. 1999
[...] subcutaneous growth hormone-releasing hormone therapy accelerates growth in growth hormone-deficient children during the first year of therapy. Geref International Study Group Journal of Clinical Endocrinology and Metabolism. 1996
Incorporation of D-Ala2 in growth hormone-releasing hormone-(1-29)-NH2 increases the half-life and decreases metabolic clearance in normal men Journal of Clinical Endocrinology and Metabolism. 1994
Drugs@FDA (openFDA) records for GEREF: NDA 019863 and NDA 020443, marketing status discontinued FDA openFDA. 2026
Federal Register notice 2013-04827: determination that GEREF (sermorelin acetate) injection was not withdrawn from sale for safety- or efficacy-related reasons Federal Register (FDA notice, 4 March 2013). 2013
EGRIFTA WR (tesamorelin) for injection, prescribing information (revised 03/2025) DailyMed (NLM). 2025
Metabolic effects of a growth hormone-releasing factor in patients with HIV New England Journal of Medicine. 2007
Effects of tesamorelin (TH9507), a growth hormone-releasing factor analog, in human immunodeficiency virus-infected patients with excess abdominal fat: a pooled analysis of two multicenter, double-blind placebo-controlled phase 3 trials with safety extension data Journal of Clinical Endocrinology and Metabolism. 2010
Effects of tesamorelin on non-alcoholic fatty liver disease in HIV: a randomised, double-blind, multicentre trial Lancet HIV. 2019
TH9507 in Patients With HIV-Associated Lipodystrophy (NCT00123253) ClinicalTrials.gov. 2013
Prohibited List 2026 (in force 1 January 2026) World Anti-Doping Agency. 2026

For research use only. Not for human or veterinary use. Not a drug, food, or dietary supplement. This page compares published research and is not medical advice or a recommendation.