Tesamorelin
| Category | Growth Hormone Secretagogues |
| Goals | Fat Loss · Muscle & Performance |
| Evidence level | Approved (FDA-approved; supported by randomized clinical trials) |
| Legal status | Prescription drug (Rx) — FDA-approved for HIV lipodystrophy |
| FDA status | Approved as Egrifta (2010), Egrifta SV, and Egrifta WR/F8 (Mar 2025) |
| Half-life | ~11 minutes (subcutaneous, healthy subjects) |
| Routes | Subcutaneous |
| CAS / MW / Sequence | 218949-48-5 · 5135.9 g/mol · 44-aa GHRH(1–44) analog with N-terminal trans-3-hexenoyl |
| Last reviewed | 2026-06-07 |
In one line
A stabilized synthetic analog of growth-hormone-releasing hormone (GHRH) that is FDA-approved to reduce excess visceral abdominal fat in adults with HIV-associated lipodystrophy.
Evidence at a glance
Tesamorelin is FDA-approved and backed by randomized, placebo-controlled clinical trials in HIV lipodystrophy showing reduced visceral adipose tissue. Use outside that indication (general fat loss, anti-aging, bodybuilding) is off-label and far less studied. See Evidence Grading Explained and the Disclaimer.
Key Takeaways
- A 44-amino-acid GHRH(1–44) analog with a stabilizing trans-3-hexenoyl group on the N-terminus that extends plasma stability.
- Works by stimulating the pituitary to release the body’s own growth hormone (a secretagogue), rather than supplying GH directly.
- FDA-approved (as Egrifta, 2010; later Egrifta SV; and the concentrated Egrifta WR / F8 formulation) for excess visceral abdominal fat in HIV lipodystrophy.
- Clinically shown to reduce visceral (deep) fat while largely sparing subcutaneous fat; benefit reverses when stopped.
- Raises IGF-1, so it carries GH-axis cautions (glucose, fluid retention) and requires prescription and monitoring.
What Is It
Tesamorelin (brand Egrifta; originally TH9507) is a synthetic analog of human growth-hormone-releasing hormone (GHRH). It reproduces the 44-amino-acid sequence of human GHRH with an added trans-3-hexenoyl (hexenoic acid) group on the N-terminal tyrosine, which improves stability in plasma and extends its effective action. It is manufactured by Theratechnologies and is the only drug FDA-approved to reduce excess abdominal fat in adults with HIV who have lipodystrophy (a redistribution of body fat associated with HIV and some antiretroviral therapy).
Mechanism of Action
- GHRH-receptor agonism (approved/clinical) — binds GHRH receptors on the anterior pituitary, stimulating release of endogenous growth hormone (GH).
- Downstream IGF-1 rise (clinical) — increased GH raises hepatic IGF-1, mediating many downstream effects.
- Visceral fat reduction (clinical) — GH promotes lipolysis preferentially in visceral adipose tissue; trials show reduced VAT with relative sparing of subcutaneous fat.
- Physiologic / pulsatile pattern — because it drives the body’s own GH release, the GH profile is more physiologic than exogenous GH injection.
Mechanism note
Tesamorelin is a secretagogue, not GH itself. Its effects depend on a functioning pituitary, and the rise in GH/IGF-1 underlies both its benefits and its metabolic cautions.
Evidence by Outcome
| Outcome | Evidence | Notes |
|---|---|---|
| Visceral fat reduction (HIV lipodystrophy) | Approved | Randomized placebo-controlled trials; ~15–18% VAT reduction over 26 wks |
| Liver fat / NAFLD (in HIV) | Clinical | Reduced liver fat / slowed fibrosis progression in HIV trials |
| IGF-1 elevation | Clinical | Consistently raises IGF-1 |
| General (non-HIV) fat loss | Anecdotal / off-label | Used off-label; far less controlled data outside the approved population |
| Muscle / performance / anti-aging | Anecdotal | Popular claims; not an approved or well-established use |
| Cognition (exploratory) | Clinical (preliminary) | Small studies in older adults / MCI; not an indication |
Reported Dosing
Not medical advice
The approved use is prescription-only and physician-supervised. Figures below summarize labeling and reported off-label practice; this is not a recommendation. See Reconstitution & Dosing Math.
| Context | Dose | Frequency | Route |
|---|---|---|---|
| FDA-approved (Egrifta SV) | 2 mg | Once daily | Subcutaneous |
| FDA-approved (Egrifta WR / F8) | 1.28 mg | Once daily | Subcutaneous |
| Off-label (reported) | Variable, often ~1–2 mg | Once daily, often before bed | Subcutaneous |
Pharmacokinetics
After subcutaneous injection in healthy subjects, tesamorelin has a mean elimination half-life of ~11 minutes; the trans-3-hexenoyl modification enhances plasma stability relative to native GHRH. The short half-life is consistent with once-daily dosing that triggers a pulse of endogenous GH. The newer Egrifta WR (F8) is a concentrated formulation reported bioequivalent to prior versions at its labeled dose. See Half-Life & Pharmacokinetics.
Side Effects & Risks
- GH-axis effects: because it raises GH/IGF-1, it can cause fluid retention, joint pain/arthralgia, peripheral edema, carpal-tunnel-like symptoms, and may worsen glucose tolerance / insulin resistance.
- Injection-site reactions: common (redness, itching, pain, bruising).
- Contraindications / cautions (per labeling): active malignancy, pituitary disorders/disruption (e.g. surgery, radiation, trauma), pregnancy; caution with diabetes/pre-diabetes and with retinopathy.
- IGF-1 monitoring: prescribers monitor IGF-1; theoretical concern about IGF-1 and cancer risk means it is contraindicated with active malignancy.
- Benefit is not durable — visceral fat tends to return after discontinuation.
- Sourcing risk: “research-chemical” tesamorelin bypasses the regulated supply chain — identity/purity not guaranteed. See Sourcing and Red Flags & Scams.
- See Side Effects & Risk Management and Bloodwork & Monitoring.
Cycling
For the approved indication, it is taken continuously while clinically indicated, not “cycled.” Off-label users sometimes run it in multi-week to multi-month blocks with IGF-1 monitoring; no evidence-based cycling standard exists outside the label. See Cycling.
Stacks It Appears In
- Off-label, sometimes combined with other GH secretagogues such as CJC-1295 and Ipamorelin — combining multiple GH-axis agents amplifies IGF-1 and side-effect risk and is not clinically validated.
- Occasionally discussed alongside GLP-1 agents (Semaglutide, Tirzepatide) for body composition — no controlled data supports these combinations.
Comparisons
- vs CJC-1295 / Ipamorelin: all stimulate endogenous GH, but tesamorelin is a GHRH analog with an FDA-approved indication and clinical trial data, whereas CJC-1295 (a GHRH analog) and Ipamorelin (a ghrelin/GHS-receptor agonist) are research-only.
- vs AOD-9604: AOD-9604 is a GH fragment designed to be lipolytic without raising IGF-1; tesamorelin works through the GH/IGF-1 axis and is approved, while AOD-9604 failed human efficacy trials.
- vs GLP-1 agonists (Semaglutide, Tirzepatide): different mechanism (GH axis vs incretin); GLP-1 drugs target general weight loss, tesamorelin targets visceral fat in a specific population.
Sourcing & Quality
Legitimately, tesamorelin is a prescription pharmaceutical (Egrifta). Material sold as a “research chemical” bypasses the regulated supply chain, so identity and purity are not guaranteed. Evaluate quality and legitimacy carefully: How to Read a CoA, Sourcing, Red Flags & Scams. Reconstitution and storage: Reconstitution & Dosing Math. No vendors are endorsed here.
Legal & Regulatory Status
(As of 2026-06-07.) Tesamorelin is FDA-approved and is a prescription drug. It was first approved as Egrifta in 2010, later as Egrifta SV, and the concentrated Egrifta WR (F8 formulation) — approved March 25, 2025 (8× more concentrated than the original; daily injection but only weekly reconstitution) — is the current marketed version, all for reducing excess visceral abdominal fat in adults with HIV-associated lipodystrophy. Any other use is off-label. Obtaining it without a prescription, or using “research-chemical” material, falls outside its legal/regulated status, and it may be prohibited in tested sport. See Regulatory & Legal Status.
FAQ
Is tesamorelin FDA-approved? Yes — for reducing excess visceral abdominal fat in adults with HIV-associated lipodystrophy. Other uses are off-label.
Is it growth hormone? No. It is a GHRH analog that stimulates your own pituitary to release GH, rather than supplying GH directly.
Does it cause general weight loss? Its proven effect is visceral (deep abdominal) fat reduction in the studied HIV population; it largely spares subcutaneous fat and is not a general weight-loss drug.
Is the benefit permanent? No — visceral fat tends to return after stopping.
Does it raise IGF-1? Yes, which is why it carries GH-axis cautions and is contraindicated with active cancer.
References
- U.S. FDA — Egrifta / Egrifta SV / Egrifta WR (tesamorelin) Prescribing Information (accessdata.fda.gov, label NDA 022505; 2019, 2025 updates).
- Falutz J. et al. (2007, 2010). Randomized placebo-controlled trials of tesamorelin for HIV-associated abdominal fat accumulation. New England Journal of Medicine; JCEM.
- Stanley T.L. et al. (2014–2019). Tesamorelin effects on visceral fat and liver fat (NAFLD) in HIV. JAMA; Lancet HIV.
- Theratechnologies / FDA (2025-03-25) — approval of EGRIFTA WR (tesamorelin F8 concentrated formulation). drugs.com/history/egrifta-wr.html
- PubChem CID 16137828 — Tesamorelin (C221H366N72O67S).
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