The best-evidenced compound in the growth hormone category, approved for a population almost nobody buying it belongs to.
what it is
Tesamorelin is a stabilised analogue of growth hormone releasing hormone. Rather than supplying growth hormone directly, it prompts the pituitary to release its own, which preserves the pulsatile release pattern that direct administration flattens. That distinction is the entire rationale for secretagogues as a class.
what the evidence shows
It was approved in 2010 for reducing excess visceral abdominal fat in people with HIV-associated lipodystrophy, on the basis of randomised trials showing meaningful reductions in visceral adipose tissue in that specific population. Subsequent work has examined liver fat in the same group. The evidence base is real, well-conducted, and narrow.
The best-evidenced compound in the growth hormone category, approved for a population almost nobody buying it belongs to.
what stays uncertain
Whether any of it generalises. The approved population has a particular metabolic profile driven by HIV and its treatment, and there is no equivalent trial evidence in healthy adults using it for body composition or anti-ageing purposes. Effects on insulin sensitivity require monitoring, and the compound is prohibited in competitive sport.
the practical note
When people describe tesamorelin as the evidence-backed option in this category, they are usually citing evidence generated in a population they do not belong to. That does not make it worthless — it makes it untested for the use in question.