Tesamorelin: what the published research reports

What is tesamorelin?

Tesamorelin is a synthetic peptide of 44 amino acids, an analogue of human growth hormone-releasing hormone (GHRH) with a hexenoyl group added at the N-terminus. The modification protects it from the enzymes that break down natural GHRH quickly. It acts at the GHRH receptor in the pituitary, which releases growth hormone in response. Its identity data, from PubChem and the FDA substance register, are on the tesamorelin page.

What did the pivotal trial measure?

The main trial was published in the New England Journal of Medicine in 2007. It enrolled 412 patients with HIV and abdominal fat accumulation and ran for 26 weeks, measuring visceral adipose tissue by CT scan. Insulin-like growth factor I (IGF-I), the marker that rises when growth hormone is released, was measured alongside it.

What have later studies looked at?

A 2014 randomised trial in JAMA, in 50 patients with HIV, measured liver fat as well as visceral fat over six months, and reported a transient rise in fasting glucose at two weeks. A 2017 pooled analysis in AIDS combined two phase 3 trials with 806 patients and compared liver enzymes between patients whose visceral fat responded and those whose did not.

Is tesamorelin an approved medicine?

Tesamorelin is approved in the United States, under the names Egrifta SV and Egrifta WR, for the reduction of excess abdominal fat in adults with HIV-associated lipodystrophy, according to the DailyMed labels. That approval covers the manufacturer's product for that indication. It does not describe research-grade material sold for laboratory use.

Which compounds are related?

Ipamorelin reaches growth hormone release through a different receptor, the ghrelin receptor. Both are in the growth hormone secretagogues category.