Tesamorelin is a lab-made version of growth-hormone-releasing hormone. It signals the pituitary gland to release more of the body’s own growth hormone. It is sold as Egrifta, and its label covers one use: reducing excess abdominal fat in adults with HIV-associated lipodystrophy [1].
That narrow use is the whole story of its evidence. Every trial covered here enrolled people with HIV. They showed a real, measurable drop in deep belly fat. They did not show weight loss, and they were not run in the general population. Readers who reach it from a weight-loss search should start there.
What the pivotal trial measured
The 2007 trial randomized 412 people with HIV and abdominal fat build-up to 2 mg of tesamorelin or placebo, injected daily for 26 weeks [2]. Of them, 86% were men. The main outcome was visceral fat, the fat packed around the organs, measured by CT scan.
Visceral fat fell 15.2% on tesamorelin and rose 5.0% on placebo. Triglycerides fell 50 mg per deciliter against a rise of 9. IGF-1, the main hormone growth hormone drives, rose 81.0% against a 5.0% fall. Glucose measures did not differ significantly between groups.
Adverse events did not differ significantly overall. But more people on tesamorelin withdrew because of one.
The second trial, and what happened on stopping
A second trial followed 404 people with HIV for 12 months [3]. Over the first 6 months, visceral fat fell 10.9% on tesamorelin against 0.6% on placebo. In people who stayed on the drug for 12 months, it fell by about 18%.
The trial then re-randomized some people from tesamorelin to placebo. In them, the improvement in visceral fat was “rapidly lost.” The effect lasts only as long as the injections do.
Liver fat: two smaller trials
Two trials led by the same research group asked whether tesamorelin reduces liver fat in people with HIV. In the first, 50 people were randomized for 6 months [4]. Visceral fat fell by a net 42 cm² against placebo (95% CI, −71 to −14). The net treatment effect on liver fat was −2.9% in lipid-to-water percentage.
The second enrolled 61 people with HIV and fatty liver disease for 12 months [5]. Liver fat fraction fell by an absolute 4.1% more than on placebo (95% CI, −7.6 to −0.7). At 12 months, 35% on tesamorelin and 4% on placebo had liver fat under 5%. The authors say longer studies are needed to know the effect on liver tissue over time.
Both are small, and both are in HIV. They are promising leads, not proof of a treatment for fatty liver in general.
What the label warns about
Because tesamorelin raises growth hormone, its warnings follow from that. After 26 weeks, 47% of treated patients had IGF-1 more than 2 standard deviations above normal [1]. The label says the effects of long-term raised IGF-1 are unknown and tells prescribers to monitor it.
Diabetes-range HbA1c (6.5% or higher) developed in 5% on the drug and 1% on placebo. In the label’s adverse-reaction table, joint pain was reported by 13% against 11%. Peripheral swelling and muscle pain were each 6% against 2%. The label also flags fluid retention, carpal tunnel syndrome and injection site reactions.
It is not to be used in pregnancy, in active cancer, or where the pituitary axis has been disrupted by surgery, radiation or injury.
Why there is no compounded tesamorelin
Egrifta was approved as a drug in 2010. On March 23, 2020, FDA deemed that approval a biologics license, and it lists tesamorelin acetate (Egrifta and Egrifta SV) among the products that changed over that day [6].
FDA told compounders that these transitioning products “will not be eligible for the exemptions for compounded drugs under sections 503A and 503B” of the federal drug law [7]. Those are the two routes a pharmacy uses to compound a drug. A tesamorelin sold as compounded therefore has no lawful route, and only the brand-name product may be prescribed.
What the trials did not show
None of these trials tested tesamorelin in people without HIV, or for muscle or anti-aging use. The trials measured fat on scans, blood lipids and blood sugar. They did not measure heart attacks or survival. Its cousin sermorelin works on the same receptor but has a much older and thinner record. For sleep claims about this hormone family, see peptides for sleep.
Egrifta is FDA-approved for that one use, fat inside the belly in adults with HIV. Its status and the studies are on the tesamorelin guide, and the broader picture is on the weight goal page.