Tesamorelin

What is Tesamorelin?

Tesamorelin (sold under the brand names Egrifta, Egrifta SV, and since 2025 Egrifta WR) is a synthetic peptide hormone. It is a stable relative of the human growth hormone-releasing factor (GHRH). It is the first and only prescription medication specifically approved to reduce unhealthy, deep belly fat in HIV patients with fat distribution disorders (lipodystrophy) [1][6].

HIV patients often suffer from lipodystrophy. This fat distribution disorder involves a dangerous buildup of visceral fat (fat around the organs), which can lead to metabolic complications such as insulin resistance and elevated blood lipid levels. Tesamorelin targets this directly by stimulating the body's own growth hormone release, which in turn promotes fat breakdown - preferably in the visceral area.

How is Tesamorelin used?

Tesamorelin is administered exclusively by subcutaneous injection (under the skin), typically into the abdominal wall. The injection site should be rotated daily to avoid skin irritation [1].

The evidence-based and approved route of administration is subcutaneous injection. There are three FDA-approved formulations that differ in vial size, reconstitution, and daily dose:

The studies on which the approval is based (LIPO-010, CTR-1011) used 2 mg subcutaneously daily for 26 weeks [4]. The newer formulations (SV, WR) deliver lower amounts of the active ingredient per injection but are not interchangeable with each other [1].

On the gray market (research vials), Tesamorelin is also injected subcutaneously, typically reconstituted with BAC water (bacteriostatic water). This practice is unproven and unapproved - it does not correspond to any clinical study or approval reality.

From Vial to Use: Calculating Reconstitution and Dose

Tesamorelin is supplied as a lyophilized powder (freeze-dried) and must be dissolved (reconstituted) with a solvent before injection. In the approved product, sterile water for injection is included [1].

Example calculation Egrifta SV (approved product):

• Vial: 2 mg Tesamorelin as powder
• Reconstitution: 0.5 mL sterile water -> concentration = 4 mg/mL
• Daily dose: 1.4 mg -> 1.4 mg / 4 mg/mL = 0.35 mL
• On a U-100 insulin syringe: 0.35 mL = 35 units (marks)
• The solution must be used immediately and any remainder discarded [1]

Example calculation research vial 2 mg (unproven user practice):

• Vial: 2 mg Tesamorelin as powder
• Reconstitution: 2 mL BAC water -> concentration = 1 mg/mL
• Target dose: 2 mg -> 2 mg / 1 mg/mL = 2.0 mL
• On a U-100 insulin syringe: 2.0 mL = 200 units (marks) - this corresponds to two full 1-mL syringes

This gray market practice is not proven and is documented here only, not recommended. If you are working with a vial and want to calculate the dose, the Injection Calculator can help you. General tips on mixing and storage can be found in the Guides.

How does Tesamorelin work?

Tesamorelin works like a messenger that signals the pituitary gland to release more of the body's own growth hormone. It is a synthetic 44-amino acid peptide and corresponds to human GHRH (growth hormone-releasing hormone). To prevent rapid enzymatic breakdown in the body, a specific trans-3-hexenoic acid unit was attached to the front end of the molecule (the so-called N-terminus), which stabilizes the molecule.

It binds to GHRH receptors in the anterior part of the pituitary gland (anterior pituitary lobe) and stimulates the natural, pulsatile release of the body's own growth hormone (GH) there. This GH in turn stimulates the liver to produce IGF-1, which promotes fat breakdown - preferably in visceral belly fat.

How effective is Tesamorelin?

The pivotal studies (LIPO-010 and CTR-1011) with over 800 HIV patients showed a reduction in visceral belly fat of about 15-18% (approximately 26 cm² in absolute numbers) over 26 weeks compared to placebo [4][6]. Positive effects on blood lipid levels and liver fat were also observed.

A meta-analysis of five randomized controlled trials (as of 2026) confirmed these results: significant reductions in visceral adipose tissue (-27.71 cm²), trunk fat (-1.18 kg), liver fat percentage (-4.28%), and waist circumference (-1.61 cm) compared to placebo [2]. A study published in 2024 in patients on integrase inhibitors (a modern class of HIV medications) confirmed efficacy under this therapy as well [3].

Tesamorelin is explicitly not approved for pure weight loss in obese patients without HIV [1].

Dosage: what the studies show - and the course

In the clinical studies (LIPO-010, CTR-1011), Tesamorelin was administered at a dose of 2 mg as a subcutaneous injection in the abdominal area [4]. The injections were self-administered by the patients. There is no dose escalation (titration) - the full dose is given from the first day.

The current FDA approval includes three formulations with different daily doses: Egrifta (2 mg), Egrifta SV (1.4 mg), and Egrifta WR (1.28 mg) [1]. These are not interchangeable. Before starting therapy, IGF-1 levels should be measured and pituitary tumors should be ruled out [1].

Studies show that the effect is reversible after discontinuing Tesamorelin - visceral fat returns over time. Continuous use is therefore recommended as long as the therapeutic benefit exists [4].

Side Effects and Common Mistakes

The most common side effects include local skin reactions such as redness and itching at the injection site (in one study 30.0% vs. 24.1% under placebo) as well as systemic complaints such as joint pain (myalgia, in one study 10.8% vs. 0% under placebo) and fluid retention/edema [4]. Other reported side effects include nausea, fatigue, and temporary increases in blood sugar.

Contraindications include active malignant diseases, pituitary tumors, pregnancy, and known hypersensitivity to Tesamorelin or mannitol [1].

Common user errors include not rotating the injection site, which can lead to increased skin reactions, and using BAC water instead of the supplied sterile water (only relevant for the approved product). You can find more tips on safe handling in the Guides. Related active ingredients can be found in the Peptide Library.

Approval and Legal Status

Tesamorelin has been officially approved in the USA (FDA) since November 2010 under the brand name Egrifta for the treatment of HIV-associated lipodystrophy in adults [1][6]. In 2018, Egrifta SV followed as an improved formulation, and in March 2025, Egrifta WR (Tesamorelin F8) was approved as another formulation that allows weekly reconstitution instead of daily [7].

In the European Union (EMA), the marketing authorization application was withdrawn by the manufacturer in 2012. Tesamorelin is not approved there. According to the FDA label, long-term cardiovascular safety has not yet been conclusively established [1].

Current Developments (2024-2026)

Research on Tesamorelin is active. A study published in 2025 examined the effects on neurocognitive impairment in HIV patients with abdominal obesity - however, the cognitive improvements did not differ significantly between Tesamorelin and placebo [5].

Several clinical trials are currently underway: The TRIUMPH study (NCT06554717) is testing Tesamorelin in combination with exercise to improve physical function in HIV patients, a phase II study (NCT07481734) is investigating the reduction of liver fat in fatty liver disease, and a study from Johns Hopkins University (NCT03150511) is exploring the effect on nerve regeneration after peripheral nerve injuries [8][9][10].

A new meta-analysis from 2026 (five RCTs) confirmed the efficacy and safety of Tesamorelin in HIV-associated lipodystrophy with significant improvements in body composition and liver fat [2].