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Tesamorelin guide

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PepCaddie provides educational summaries of published and registered research. It does not sell peptides, provide medical advice, or recommend the use of any investigational substance. Discuss health decisions with a qualified healthcare professional.

This tesamorelin guide covers a medicine that is genuinely FDA-approved, for one narrow use: reducing excess abdominal fat in adults with HIV-associated lipodystrophy1. That is worth stating up front, because tesamorelin is widely discussed as a fat-loss or anti-ageing compound, and its own approved label says in writing that it is not indicated for weight loss1.

The short answer

  • What it is: a synthetic analogue of growth hormone-releasing hormone. It does not supply growth hormone; it prompts the body to release its own, which is why IGF-1 rises on treatment135.
  • Approved? Yes, but only for excess abdominal fat in adults with HIV-associated lipodystrophy1.
  • Not for weight loss: the label says so directly, and describes the effect as weight neutral1.
  • The effect stops when treatment stops: visceral fat came back in the group switched to placebo4.
  • Prohibited in sport at all times, named on the WADA list under growth hormone releasing factors2.

What the approved use is based on

Two randomised placebo-controlled trials in adults with HIV and abdominal fat accumulation. Pooled, visceral abdominal fat fell about 15 per cent more than on placebo, with triglycerides improving and IGF-1 roughly doubling35. Notably, fat under the skin did not change much: the effect is specific to the deep abdominal fat that the indication targets.

The extension trial answered the question people usually ask second. Continuing treatment held the reduction at about 18 per cent over a year. In the group switched to placebo, the fat returned, and the authors state that the effects do not last beyond the duration of treatment4.

What happened outside that use

This is where the picture turns. A trial in people with type 2 diabetes and without HIV found no significant difference in the insulin response it measured, and no difference in fasting glucose, HbA1c or overall diabetes control7810.

On thinking and memory, the record is mixed and trending negative. An early trial in older adults reported a cognitive benefit9108. A later trial in people with HIV found no difference against standard care, and a small placebo-controlled pilot in older adults found nothing on any of its pre-specified measures7810.

A twelve-month trial in people with HIV and fatty liver did find liver fat falling by about 37 per cent relative to placebo6. That is a real result in 61 people, described as tentative by its own authors, and it is not an approved use.

No trial was identified testing tesamorelin for body composition or performance in healthy adults without HIV[unverified].

What the label warns about

There is no boxed warning, but the warnings that exist are substantive. Because tesamorelin raises growth hormone, the label cautions about the risk of neoplasms, tells prescribers not to treat people with active malignancy, and says to stop if there is evidence of recurrent malignancy1. It is contraindicated in active malignancy, in pregnancy, in people whose hypothalamic-pituitary axis is disrupted, and in known hypersensitivity1.

IGF-1 rises substantially and the label says the effects of prolonged elevation are unknown, with monitoring advised135. Treatment can cause glucose intolerance: raised HbA1c occurred in 5 per cent of treated participants against 1 per cent on placebo1. Injection-site reactions affected a quarter of participants1, and about half developed antibodies to the drug, rising to 85 per cent among those who had hypersensitivity reactions1. Long-term cardiovascular safety has not been established1.

How long it stays in the body

Unusually briefly. The half-life is measured in minutes, between about 8 and 38 minutes depending on the formulation1. The effect on growth hormone release is what lasts, not the drug itself.

Where the rest of the detail lives

The interactive library on the homepage carries the fuller reference entry for tesamorelin. For anyone prescribed it, the approved labelling linked below sets out how it is used, monitored and stopped.

Open the full tesamorelin reference in the library

References

These are the sources behind this page, listed so you can read them yourself rather than take our word for it. Animal and laboratory findings do not establish that something works or is safe in people. Doses and protocols shown on a study card are that study's research parameters, not recommendations. PepCaddie does not sell peptides and does not choose a dose for anyone; this is educational material and it does not replace a qualified healthcare professional.

  • Pivotal trial in HIV-associated abdominal fat

    2007

    Human randomised trial

    Adults with HIV and abdominal fat accumulation2 mg daily by subcutaneous injection, as reported in this trial studied26 weeksVisceral fat outcome

    The dose above is the amount used in this study. It is research information, not a recommended dose, and PepCaddie does not convert study doses into human doses.

    The trial that established the approved use. Visceral abdominal fat measured by CT fell 15.2 per cent on tesamorelin while rising 5 per cent on placebo, and triglycerides improved. IGF-1 rose 81 per cent.

    Limitation: Twenty-six weeks, with an imaging measurement rather than a health outcome. More participants on tesamorelin withdrew because of an adverse event, and the authors themselves hedged, describing effects that might be useful.

    Randomised, double-blind, placebo-controlled trialView study: Pivotal trial in HIV-associated abdominal fat

  • 52-week extension, including what happens after stopping

    2008

    Human randomised trial

    Adults with HIV and abdominal fat accumulation2 mg daily by subcutaneous injection, as reported in this trial studied52 weeksVisceral fat outcome

    The dose above is the amount used in this study. It is research information, not a recommended dose, and PepCaddie does not convert study doses into human doses.

    Continuing treatment held the reduction in visceral fat at about 18 per cent over a year. In the group switched to placebo, visceral fat came back. The authors state plainly that the effects do not last beyond the duration of treatment.

    Limitation: The group that stopped treatment was small, 50 people, and not all lipid measures moved favourably over the year.

    Randomised extension with a withdrawal armView study: 52-week extension, including what happens after stopping

  • Pooled analysis of both pivotal trials

    2010

    Human randomised trial

    Adults with HIV on antiretroviral therapy2 mg daily by subcutaneous injection, as reported in these trials studied26 weeks, with a 26-week extensionVisceral fat outcome

    The dose above is the amount used in this study. It is research information, not a recommended dose, and PepCaddie does not convert study doses into human doses.

    Across both pivotal trials, visceral fat fell about 15 per cent more on tesamorelin than placebo, triglycerides improved, and IGF-1 roughly doubled. Subcutaneous abdominal fat did not change significantly, which is the point: the effect is specific to visceral fat.

    Limitation: A pooled analysis of two trials whose individual effect sizes differed, with imaging and blood measurements rather than health outcomes, over a year at most.

    Pooled analysis of two randomised placebo-controlled trialsView study: Pooled analysis of both pivotal trials

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