Ipamorelin vs Tesamorelin

Different receptors

Ipamorelin acts at the ghrelin receptor (GHSR-1a). Tesamorelin is a synthetic analogue of growth hormone-releasing hormone and acts at the GHRH receptor. Development code TH9507.

Two receptors, two classes: a growth hormone secretagogue and a GHRH analogue. The same split separates ipamorelin from sermorelin and from CJC-1295 — see ipamorelin vs sermorelin.

The evidence gap is the real difference

This is the part that matters, and it is unusually one-sided.

Tesamorelin is a licensed medicine. It is marketed as Egrifta and Egrifta SV and is indicated for the reduction of excess abdominal fat in HIV-associated lipodystrophy — the only approved treatment for that indication. Its evidence base is a meta-analysis of five randomised controlled trials in that population (PMID 41545261), which reported a significant reduction in visceral adipose tissue — a mean difference of −27.71 cm² — along with reductions in trunk fat, waist circumference and hepatic fat, and a modest increase in lean body mass. There is also a review of its profile in that condition (PMID 22050344).

Ipamorelin's record is one characterisation study, animal and in-vitro, from 1998 (PMID 9849822). It reported selectivity: growth hormone release without meaningful elevation of cortisol, ACTH or prolactin at GH-releasing doses.

A meta-analysis of five human RCTs against a single animal characterisation. That is the gap, stated plainly.

Two warnings about reading that gap

First: tesamorelin's evidence is population-specific. Those five trials were run in people with HIV-associated lipodystrophy. That is the indication the authorisation covers and it is the population the numbers come from. A result in one clinical population is not a general result, and the meta-analysis does not become a statement about anyone else by being quoted somewhere else.

Second: the licence does not travel with the molecule. Tesamorelin holds a marketing authorisation as a licensed finished medicine. What we supply is tesamorelin as an unlicensed research compound, with an analytical specification rather than a Summary of Product Characteristics. The same distinction applies to tirzepatide and is set out at length in are peptides legal in the UK.

Side by side

Why they turn up in the same searches

Because both are grouped under the same informal heading in the way the market talks, and because a third compound sits between them: CJC-1295 + Ipamorelin pairs a GHRH analogue with a secretagogue in one vial, which puts both receptor classes in a single product and makes the two names appear together constantly.

No published literature exists on that blend as a blend. Each component has its own record — CJC-1295's is a randomised placebo-controlled double-blind trial in healthy adults (PMID 16352683), ipamorelin's is the 1998 characterisation — and neither describes what happens when they are supplied together.

Supply note. Peptiq supplies research compounds for laboratory research use only. We are not a pharmacy and we do not supply licensed medicines. Where a licensed medicine is named on this page it is named to draw a distinction, not because we sell it, and nothing here is guidance on use.