Tesamorelin. A Signal to the Pituitary
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| GHRH ANALOGUE · 44 AMINO ACIDS · TH9507 | |
| What it is | A synthetic copy of human GHRH (all 44 amino acids) with an extra chemical group that makes it last longer |
|---|---|
| Other names | TH9507 and tesamorelin acetate; brand names Egrifta, Egrifta SV and Egrifta WR |
| Molar mass | About 5,136 g/mol |
| Target | GHRH receptors on the pituitary gland, which then releases growth hormone |
| Approved use | US and Canada: reducing excess abdominal fat in adults with HIV and lipodystrophy |
| Company | Developed by Theratechnologies; the company was bought by Future Pak in September 2025 |
| Status | No marketing authorisation in the EU or the UK |
Your brain uses a small hormone to tell the pituitary gland when to release growth hormone. Tesamorelin is a sturdier, lab-made version of that hormone. In 2010 it became the first US medicine for the deep belly fat that some people with HIV build up on treatment. This guide covers what it is, what the trials found and why Europe said no.
Why People Talk About It
Tesamorelin was created by Theratechnologies, a drug company in Montreal, under the code TH9507. The team took the full natural form of growth hormone-releasing hormone, or GHRH, and added a small chemical cap to one end so the body would not break it down so fast.
Modern HIV medicines saved millions of lives, but some people on them gained fat deep inside the abdomen, around the organs, while their arms and legs grew thinner. This visceral fat is linked to heart and liver problems. Tesamorelin was tested as a way to shrink it by nudging the body to make more of its own growth hormone.
Two large trials led to US approval under the brand name Egrifta. European regulators were less convinced, and the application there was withdrawn in 2012. Since then, researchers have looked at fatty liver, memory and physical fitness. The pages below go through it step by step.
- A chain of 44 amino acids
- FDA approval in 2010
- Not licensed in the EU or UK
Tesamorelin is a prescription medicine in the US and Canada for one specific use. It has no marketing authorisation in the EU or the UK. Research-grade tesamorelin is meant for laboratory work only, and nothing here is medical advice.
What You Will Find Here
- What Is Tesamorelin? – How tesamorelin talks to the pituitary and what follows
- History – From a Montreal lab to Egrifta, and the European withdrawal
- Research – Belly fat, liver fat and memory: what the trials measured
- Rules & Safety – Where it is approved, side effects and who should avoid it
- Sourcing – Points laboratories check before buying