Tesamorelin: what the evidence shows

What the human research shows

A genuinely well-evidenced drug for a narrow purpose — and a good example of how a real A-grade outcome in one population gets stretched into claims for everyone else. The visceral-fat effect is solid in HIV lipodystrophy. Nothing on this page supports the way it is marketed on the grey market.

Evidence profile0–5

Metabolic & weightA3.3
Cardiovascular—0.0
Muscle & growth—0.0
Healing & repair—0.0
Neuro & sleepC0.7
Immune & inflammation—0.0
Sexual & hormonal—0.0
Skin & appearance—0.0
Ageing & longevity—0.0

Each score is confidence × effect size, taken from the best-evidenced benefit in that domain: the grade (A–D) sets the confidence, the measured effect sets the size. Hover a domain to see the outcomes behind it. Adverse effects are excluded and listed separately below.

Outcome	Grade	Effect size	Human studies	Where the evidence comes from
Visceral fat (HIV lipodystrophy)	AEstablished	Moderate	2 phase 3 RCTs (n=816)	Pooled phase 3: visceral adipose tissue −15.2% at 26 weeks vs +5% on placebo; effect lost within 26 weeks of stopping.1
Liver fat (HIV with NAFLD)	BProbable	Moderate	1 RCT (n=61)	Hepatic fat fraction fell by about a third over 12 months vs placebo; a specific population, one trial.2
Cognition in older adults	CWeak	Small	1 RCT (n=152)	20 weeks of tesamorelin improved some executive-function measures in healthy older adults and those with mild cognitive impairment. Single trial, never replicated or developed further.3
Fat loss in healthy adults	DNo human evidence	Not measurable	None	Not studied. The approved population is not a proxy for the general public.
IGF-1 elevation and glucose effectsadverse	AEstablished	Small	Phase 3 programme	Raises IGF-1 as intended; small rises in blood glucose and injection-site reactions are documented. Long-term cancer risk at elevated IGF-1 is the reason for the narrow label.1

AMultiple good human trials, consistentBSome human trials, mostly consistentCFew or weak human studiesDAnimal or anecdotal onlyeffect size · red = adverse

Literature searched to 2 September 2026. Human studies only; animal and cell work informs the mechanism section and nothing else.

Registered trials

ClinicalTrials.gov lists 18 interventional studies naming Tesamorelin as an intervention — 10 completed, 3 recruiting, and 8 with results posted to the registry.

A registration is not a result. Anyone can register a study, and many never report — so this list shows what has been attempted, not what has been shown. The graded evidence above is the answer to whether something works.

Study	Phase	Status	Participants	Sponsor	Results
Body Composition and Adipose Tissue in HIVNCT03226821 · started Feb 2018	Phase 4	Terminated	6	Columbia University	Posted
TH9507 Extension Study in Patients With HIV-Associated LipodystrophyNCT00608023 · started Aug 2007	Phase 3	Completed	263	Theratechnologies	Posted
Phase II Trial of Tesamorelin for Cognition in Aging HIV-Infected PersonsNCT02572323 · started Feb 2017	Phase 2	Completed	73	University of California, San Diego	Posted
Growth Hormone Releasing Hormone Analog to Improve Nonalcoholic Fatty Liver Disease and Associated Cardiovascular RiskNCT03375788 · started Jan 2019	Phase 2	Completed	51	Massachusetts General Hospital	Posted
Efficacy and Safety Study of Tesamorelin in Chronic Obstructive Pulmonary Disease (COPD) Subjects With Muscle WastingNCT01388920 · started Sept 2011	Phase 2	Terminated	3	Theratechnologies	Posted
Tesamorelin Effects on Liver Fat and Histology in HIVNCT02196831 · started Jul 2015	N/A	Completed	61	Massachusetts General Hospital	Posted
Effects of Growth Hormone Releasing Hormone in HIVNCT01263717 · started Dec 2010	N/A	Completed	54	Massachusetts General Hospital	Posted
Effect of Short Term Growth Hormone Releasing Hormone in Healthy MenNCT00850564 · started Feb 2009	N/A	Completed	15	Massachusetts General Hospital	Posted

10 further studies are registered. Participant counts marked * are the sponsor's estimate, not a final enrolment. Source: ClinicalTrials.gov, read directly from the registry and refreshed weekly.

What it is

Tesamorelin is the first 44 amino acids of natural growth-hormone-releasing hormone with a chemical cap added to stop it being broken down quickly. Given as a daily injection, it stimulates the pituitary to release growth hormone in a pattern closer to the body's own than injected growth hormone itself.

Theratechnologies won FDA approval in 2010 as Egrifta, for a specific problem — the abdominal fat accumulation seen in some people with HIV on older antiretroviral drugs. It has never been approved for anything else, and the European application was withdrawn.

How it is thought to work

By acting on GHRH receptors in the pituitary it raises pulsatile growth hormone and, downstream, IGF-1. Growth hormone mobilises fat, particularly visceral fat, which is why the trials measured abdominal fat by CT scan rather than body weight — overall weight changes little.

What is still unknown

Whether any of the fat effect applies to people without HIV lipodystrophy; it has not been tested.
Long-term safety of sustained IGF-1 elevation; the approval carries warnings about active malignancy and glucose intolerance.
Whether the single cognition trial would replicate.

The molecule and how long it lasts

Identity

Formula: C221H366N72O67S
Molecular weight: 5136 g/mol
CAS number: 218949-48-5
PubChem: CID 16137828

PubChem record, read 23 September 2026.

Pharmacokinetics

Route: Subcutaneous injection, once daily
Half-life: About 8 minutes
Licensed regimen (Egrifta SV): 1.4 mg (0.35 mL reconstituted) subcutaneously once daily

From the approved product's prescribing information: Egrifta SV prescribing information (DailyMed) The regimen is the label's own wording, reproduced as a regulatory fact.

Regulatory status

European Union

Not authorised

The Egrifta marketing authorisation application was withdrawn on 26 June 2012 after the CHMP could not conclude a positive benefit–risk balance.

United States

Approved (Egrifta), prescription-only

Approved for excess abdominal fat in HIV-associated lipodystrophy. Prescribing outside that indication is a clinical decision; selling vials for 'research' is not a lawful supply route.

United Kingdom

Not licensed

No MHRA licence. Unlicensed medicine when supplied for human use.

Australia

Not registered

Not on the ARTG; prescription-only if obtained at all.

Canada

Authorised (Egrifta), prescription-only

Authorised in Canada for HIV-associated abdominal fat. Vials sold online were nonetheless among the products Health Canada seized in August 2025.

Sport (WADA)

Prohibited at all times

GHRH analogue: S2.2.4, growth hormone releasing factors.

Questions people actually ask

Does tesamorelin burn belly fat?

In people with HIV-associated lipodystrophy, yes — about 15% less visceral fat after six months in two phase 3 trials. In anyone else it has not been tested, and the fat returns when treatment stops.

Is tesamorelin the same as growth hormone?

No. It prompts the body to release its own growth hormone rather than supplying it. The downstream effects overlap, including higher IGF-1.

Is tesamorelin legal?

It is a prescription medicine in the United States for one indication. It is not authorised in the EU or UK, and it is banned in sport.

One page per claimed effect

ADoes Tesamorelin help with visceral fat?2 phase 3 RCTs (n=816)
BDoes Tesamorelin help with liver fat?1 RCT (n=61)
CDoes Tesamorelin help with cognition in older adults?1 RCT (n=152)
DDoes Tesamorelin help with fat loss in healthy adults?None
AHow common is IGF-1 elevation and glucose effects with Tesamorelin?Phase 3 programme

References

1
Falutz J, et al. Effects of tesamorelin, a growth hormone-releasing factor, in HIV-infected patients with abdominal fat accumulation: pooled analysis of two phase 3 trials.J Acquir Immune Defic Syndr, 2010;53:311–322816 participants; the approval basis.
2
Stanley TL, et al. Effects of tesamorelin on non-alcoholic fatty liver disease in HIV: a randomised, double-blind, placebo-controlled trial.Lancet HIV, 201961 participants, 12 months.
3
Baker LD, et al. Effects of growth hormone-releasing hormone on cognitive function in adults with mild cognitive impairment and healthy older adults.Arch Neurol, 2012;69:1420–1429152 adults, 20 weeks; not replicated.

Change log

2026-09-02Full page. Added liver-fat, cognition and IGF-1 rows; regional status; FAQ.
2026-09-01Initial publication.