Tesamorelin
Trans-3-hexenoyl growth hormone-releasing factor (1-44) amide · Egrifta · EGRIFTA SV · EGRIFTA WR · TH9507
The only FDA-approved GHRH analogue, proven to shrink visceral abdominal fat.
Typical dose
2 mg
once daily
Range
1–2
mg
Half-life
8 min
see Dosing
Evidence
Human trials
Subcutaneous
What it is
Tesamorelin is the full 44-amino-acid human GHRH sequence with a trans-3-hexenoic acid group attached to the N-terminal tyrosine. That fatty-acid cap is what stops DPP-4 from clipping the peptide apart, and it does so without changing how the molecule sits in the GHRH receptor.
It is the only GHRH analogue currently approved anywhere. The FDA cleared it in 2010 for reducing excess abdominal fat in HIV patients with lipodystrophy, on the strength of two phase 3 trials in which visceral adipose tissue fell roughly 15% over 26 weeks — a -15.4% treatment effect in the pooled analysis — while subcutaneous fat was largely spared. Later work in the same population showed a reduction in liver fat and in NASH progression.
That visceral-fat selectivity is why it gets used outside its label. It is not a general weight-loss drug — trial subjects lost visceral fat and liver fat without meaningful change in total body weight — and the effect reverses once the drug is stopped. It is also the most expensive peptide in this group by a wide margin.
How it works
Tesamorelin binds the GHRH receptor on pituitary somatotrophs and drives endogenous GH release through the normal cAMP/PKA pathway. The hexenoyl group blocks DPP-4 degradation, so the peptide reaches the receptor intact instead of being clipped apart in plasma — but it still clears in minutes (8 minutes on the EGRIFTA SV label, 26-38 minutes for the original formulation), so daily dosing raises IGF-1 into the upper physiological range rather than producing a continuous supraphysiological signal.
The visceral-fat effect comes from GH itself. Growth hormone is strongly lipolytic in visceral adipose tissue, where receptor density and lipolytic responsiveness are higher than in subcutaneous fat, and it also suppresses the local cortisol-regenerating enzyme 11beta-HSD1. That combination is why the fat loss in the trials was concentrated in the abdominal compartment and in the liver.
Dosing
The label dose is formulation-specific — 2 mg for the original EGRIFTA, 1.4 mg for EGRIFTA SV, 1.28 mg for EGRIFTA WR — because bioavailability differs between them, not because the target exposure changed. Research-grade vials have no such calibration, so 1-2 mg daily is the practical range.
Reconstitution calculator
Pre-loaded with Tesamorelin’s vial size, water volume and typical dose. Change anything.
Typical: 2 mg · range 1–2
Draw to
100 u
1 mL · 2 mg
Concentration
2 mg/mL
20 mcg per unit
Doses per vial
1
Vial lasts
1 day
CheckThe draw fills more than 90% of the barrel. Workable, but there is no room for an air bubble or a correction.
Once mixed
The label calls for immediate use with no refrigeration; a bacteriostatic-water reconstitution should be kept at 2-8C and used within 2-3 weeks.
The pharmacy product is reconstituted with plain sterile water and injected immediately; bacteriostatic water is what makes a multi-day research vial possible. A 2 mg vial in 1 mL gives 2 mg/mL, so a 2 mg dose is 1.0 mL — a full U-100 syringe. A 10 mg vial in 2 mL gives 5 mg/mL and puts the same dose at 0.4 mL, which is why larger vials are worth buying for this compound.
Storage
Before mixing
The pharmacy product is stored at room temperature, 20-25C, protected from light; research-grade lyophilised powder keeps for years sealed and dry at -20C.
After mixing
The label calls for immediate use with no refrigeration; a bacteriostatic-water reconstitution should be kept at 2-8C and used within 2-3 weeks.
Reported benefits
- ▪The only GHRH analogue with phase 3 efficacy data and regulatory approval
- ▪Reduced visceral adipose tissue by roughly 15% over 26 weeks in the pivotal trials, and about 17.5% by week 52 on continued treatment
- ▪Cut liver fat and improved NASH endpoints in a later randomised trial
- ▪Spares subcutaneous fat rather than stripping it alongside visceral fat
- ▪Raises IGF-1 through the pituitary, leaving the axis intact
- ▪Improved triglycerides in the trial populations
Side effects
- ▪Arthralgia and pain in the extremities — among the most common trial complaints
- ▪Injection-site erythema, pruritus, pain and bruising
- ▪Peripheral oedema and myalgia
- ▪Paraesthesia and hypoaesthesia, including carpal tunnel symptoms
- ▪Worsened glucose tolerance and rising HbA1c — 5% of tesamorelin patients crossed an HbA1c of 6.5% by week 26 versus 1% on placebo
- ▪Nausea and vomiting
- ▪Hypersensitivity reactions including rash and urticaria
Do not use if
- ▪Disruption of the hypothalamic-pituitary axis — hypophysectomy, hypopituitarism, pituitary tumour or surgery, head irradiation or head trauma
- ▪Active malignancy of any kind
- ▪Pregnancy
- ▪Known hypersensitivity to tesamorelin or to mannitol
Evidence level — Human trials
Controlled human clinical data exists.
FDA-approved as EGRIFTA SV and EGRIFTA WR for reducing excess abdominal fat in HIV-associated lipodystrophy; every other indication is off-label.
Commonly run with
Ipamorelin
The selective GHRP: a clean GH pulse with almost no cortisol, prolactin or hunger.
300 mcg · 1-3x daily
GHRP-2
Potent, well-studied GHRP with a bigger pulse than ipamorelin and more cortisol.
100 mcg · 2-3x daily
GHRP-6
The original GHRP: solid GH release and the strongest hunger response of the group.
100 mcg · 2-3x daily
Hexarelin
The most potent GHRP, and the fastest to stop working if you run it continuously.
100 mcg · 1-2x daily
Semaglutide
Long-acting GLP-1 agonist dosed weekly; the reference compound for appetite-driven fat loss.
1 mg · Once weekly
Tirzepatide
Weekly dual GIP/GLP-1 agonist; beats semaglutide on total weight loss in head-to-head data.
5 mg · Once weekly
Tesamorelin FAQ
Will it work for visceral fat in someone without HIV?+
The mechanism is not HIV-specific — GH is lipolytic in visceral fat in anyone — and small trials in non-HIV populations with abdominal obesity and NAFLD have shown similar directional effects. But the ~15% figure everyone quotes comes from HIV lipodystrophy patients, and applying it to general abdominal obesity is an extrapolation, not a finding.
Does the fat come back when you stop?+
Yes. In the phase 3 extension, patients randomised off tesamorelin regained visceral fat toward baseline over the following 26 weeks. The drug maintains a state rather than producing a permanent change, which is why the label frames it as ongoing therapy.
Why is it so much more expensive than other GHRH peptides?+
The daily dose is 1-2 mg where Mod GRF 1-29 runs at 100-300 mcg, so a month of tesamorelin is 30-60 mg of peptide versus 3-9 mg. The synthesis is also harder — 44 residues plus an N-terminal acylation instead of 29. The cost difference is mostly milligrams, not margin.
What does it do to blood sugar?+
It worsens it. GH antagonises insulin action, and the label reports 5% of tesamorelin patients versus 1% on placebo crossing an HbA1c of 6.5% by week 26. Only one dose level (2 mg) was ever studied, so there is no dose-response data, and the pooled phase 3 analysis reported no clinically meaningful group difference in glucose parameters at weeks 26 or 52. Anyone running it for months should still be checking fasting glucose and HbA1c, and it is a poor choice on top of existing insulin resistance.
Does it need to be taken at night?+
The label does not specify a time and the trials did not require one. Night-time dosing on an empty stomach is a community convention borrowed from short-acting GHRH peptides, since insulin from a recent meal blunts the GH response. Consistency of timing matters more than which time you pick.
References
- 1.Metabolic effects of a growth hormone-releasing factor in patients with HIV — N Engl J Med (2007) PMID 18057338
- 2.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 — J Clin Endocrinol Metab (2010) PMID 20554713
- 3.Effects of tesamorelin on non-alcoholic fatty liver disease in HIV: a randomised, double-blind, multicentre trial — Lancet HIV (2019) PMID 31611038
More gh secretagogues
CJC-1295 no-DAC
Short-acting GHRH fragment that sharpens one GH pulse, almost always run with a GHRP.
100 mcg · 1-3x daily
CJC-1295 with DAC
Albumin-binding GHRH analogue that lifts GH and IGF-1 for days from one injection.
1000 mcg · 1-2x weekly
GHRP-2
Potent, well-studied GHRP with a bigger pulse than ipamorelin and more cortisol.
100 mcg · 2-3x daily
GHRP-6
The original GHRP: solid GH release and the strongest hunger response of the group.
100 mcg · 2-3x daily