Tesamorelin

What it is

Tesamorelin is a synthetic 44-amino-acid analog of growth hormone-releasing hormone (GHRH), sold under the brand names Egrifta SV and Egrifta WR. It is FDA-approved for one specific, narrow use: reducing excess abdominal fat in HIV-infected adults with lipodystrophy caused by antiretroviral therapy (the fat depot measured in its trials is visceral adipose tissue). The label explicitly states it is not indicated for general weight loss and does not improve antiretroviral adherence. Mechanistically, it binds pituitary GHRH receptors to stimulate the body's own pulsatile growth hormone release, raising IGF-1 and promoting lipolysis of visceral fat. The evidence base for the approved indication is unusually solid for a peptide drug: the pivotal Falutz et al. 2007 NEJM trial (412 patients, 26 weeks) found a 15.2 percent reduction in visceral adipose tissue versus a 5.0 percent increase with placebo, with IGF-1 rising 81 percent; a pooled analysis of two phase 3 trials showed the fat reduction sustained through 52 weeks. It is cleared very quickly, with a single-dose half-life of 8 to 11 minutes reported on current FDA labels, and under 4 percent subcutaneous bioavailability. It must be reconstituted from lyophilized powder before each injection. Outside the approved indication, tesamorelin is discussed in anti-aging and fitness communities for general visceral fat reduction, an off-label use not supported by the same trial evidence.

Dose ranges

Study-backed ranges carry a source you can open. Community ranges are widely reported but not clinically established - treat them as what people do, not as advice.

Reconstitution & storage

Two current, non-interchangeable commercial formulations. Egrifta SV: 2 mg lyophilized powder in a single-dose vial, reconstituted with 0.5 mL Sterile Water for Injection (roll gently 30 seconds, do not shake) to give 2 mg/0.5 mL; withdraw 0.35 mL (1.4 mg) for the daily dose; administer immediately and discard any unused solution (do not freeze or refrigerate). Egrifta WR: 11.6 mg lyophilized powder in a multi-dose vial, reconstituted with 1.3 mL Bacteriostatic Water for Injection, USP (swirl, do not shake) to give approximately 8 mg/mL; withdraw 0.16 mL (1.28 mg) once daily; one reconstituted vial supplies 7 daily doses and may be kept at room temperature for up to 7 days. The original 1 mg/vial Egrifta formulation (studied in the pivotal trials at a 2 mg/day dose, i.e. two vials) appears to have been discontinued in favor of SV and WR; this discontinuation was not independently verified against a primary source during this research. Source: DailyMed labels for Egrifta SV and Egrifta WR.

Common stacks

Interactions & cautions

The FDA label warns that because tesamorelin raises growth hormone, it may alter the clearance of drugs metabolized by cytochrome P450 liver enzymes, including corticosteroids, sex steroids, anticonvulsants, and cyclosporine, so concomitant use should be monitored. Patients on glucocorticoid replacement for previously diagnosed hypoadrenalism may need an increased maintenance or stress dose after starting tesamorelin. Tesamorelin also raises IGF-1 (about 81 percent in the tesamorelin group in the pivotal trial, versus a slight decline with placebo) and is associated with a higher rate of new or worsening glucose intolerance and elevated HbA1c than placebo, which is relevant for patients on antidiabetic therapy. In clinical trials, anti-tesamorelin IgG antibodies developed in about 50 percent of patients by 26 weeks and 47 percent by 52 weeks, with roughly 60 percent of those showing cross-reactivity to endogenous GHRH; the clinical significance of this immunogenicity was not fully characterized in the label. Source: DailyMed Egrifta SV and Egrifta WR labels, Drug Interactions and Warnings sections.

Questions people ask

Sources

1. [1]EGRIFTA SV (tesamorelin) for injection - full prescribing informationlabelFDA-approved indication, dose (1.4 mg SC once daily), reconstitution steps, contraindications, warnings (malignancy, IGF-1, HPA axis, critical illness, glucose intolerance), adverse reaction rates, immunogenicity, drug interactions, and single-dose pharmacokinetics (8-minute half-life) for Egrifta SV.
2. [2]EGRIFTA WR (tesamorelin) for injection - full prescribing informationlabelEgrifta WR dose (1.28 mg SC once daily), reconstitution with bacteriostatic water from an 11.6 mg multi-dose vial (7-day use), storage, and single-dose pharmacokinetics (11-minute half-life).
3. [3]Metabolic effects of a growth hormone-releasing factor in patients with HIV (Falutz et al., N Engl J Med 2007) PMID 18057338studyPivotal 26-week phase 3 trial (n=412, 2 mg/day of the original formulation): 15.2 percent visceral adipose tissue reduction versus a 5.0 percent increase with placebo, and an 81 percent increase in IGF-1.
4. [4]Effects of tesamorelin (TH9507), a growth hormone-releasing factor analog, in HIV-infected patients with excess abdominal fat: a pooled analysis of two phase 3 trials with safety extension data (Falutz et al., J Clin Endocrinol Metab 2010) PMID 20554713studyPooled analysis of the two pivotal phase 3 trials showing visceral fat reduction sustained through 52 weeks, preserved subcutaneous fat, improved lipids, and overall tolerability without clinically meaningful glucose changes.
5. [5]Effect of tesamorelin on visceral fat and liver fat in HIV-infected patients with abdominal fat accumulation: a randomized clinical trial (Stanley et al., JAMA 2014) PMID 25038357studyIndependent 6-month RCT (n=50) showing tesamorelin reduced both visceral fat and liver fat versus placebo, with a transient fasting glucose increase at 2 weeks that normalized by month 6.
6. [6]Tesamorelin - LiverTox: Clinical and Research Information on Drug-Induced Liver Injury (NCBI Bookshelf)review2010 FDA approval date, mechanism-of-action summary, and hepatotoxicity likelihood category E (unlikely cause of clinically apparent liver injury; no reported cases).
7. [7]Introduction - Clinical Review Report: Tesamorelin (Egrifta) (CADTH, via NCBI Bookshelf)reviewHealth-technology-assessment description of mechanism, patient-selection criteria (waist circumference and CT-confirmed visceral fat thresholds), and the 2 mg/day trial dose.
8. [8]References - Clinical Review Report: Tesamorelin (Egrifta) (CADTH, via NCBI Bookshelf)referenceConfirms the second pivotal phase 3 trial (CTR-1011, n=404) exists only as an unpublished, confidential manufacturer clinical study report rather than an independently accessible peer-reviewed paper, and gives the Falutz 2007 and Stanley 2014 citations.
9. [9]Tesamorelin | C221H366N72O67S | CID 16137828 (PubChem)referenceMolecular formula (C221H366N72O67S) and PubChem compound identity (CID 16137828) for tesamorelin free base.
10. [10]Tesamorelin Peptide Guide: Benefits, Uses, Dosage, Bodybuilding (Muscle & Brawn)communityIllustrates community and off-label dosing discourse (for example 1 to 2 mg/day, 12 to 26 week cycles) for anti-aging and bodybuilding use outside the FDA-approved HIV indication; not clinical evidence.