Tesamorelin

Visceral fat

US approval covers reduction of excess abdominal fat in adults with HIV lipodystrophy. The prescribing information does not approve tesamorelin for weight loss and says long-term cardiovascular safety is unknown.²⁰⁸

Mechanism

Tesamorelin is a synthetic analogue built from the 44-amino-acid human growth hormone-releasing factor sequence, with an added chemical modification. It prompts the pituitary gland to release the body’s own growth hormone, which raises IGF-1. It is not growth hormone itself.²⁰⁸

Visceral and subcutaneous fat

Visceral fat surrounds internal organs. Subcutaneous fat sits under the skin. The trials measured these separately: a reduction in visceral fat does not promise the same change in visible belly fat, overall body weight or physical performance.^209,210

Visceral-fat trial results

The strongest evidence comes from selected adults with HIV and excess abdominal fat. The original studies followed people for months, not days.

412 adults

In a randomized trial, CT-measured visceral fat fell 15.2% with tesamorelin and rose 5.0% with placebo. Participants had HIV and abdominal fat accumulation; 86% were men. The study used the original formulation, 2 mg by subcutaneous injection daily.²⁰⁹

A second pivotal trial

A separate trial enrolled 404 adults with HIV and excess abdominal fat. At six months, visceral fat changed by -10.9% with tesamorelin versus -0.6% with placebo. Abdominal subcutaneous fat did not change.²¹²

After treatment stopped

In the first trial extension, continued treatment maintained an 18% reduction in visceral fat from the original baseline at 52 weeks. Fat reaccumulated after participants switched to placebo. The extension continued follow-up of the same cohort.²¹³

Evidence outside HIV

A 12-month randomized trial studied 60 adults with abdominal obesity and reduced growth hormone secretion. The treatment difference in visceral fat was -35 cm2; the subcutaneous-fat difference was not significant.²¹⁰

Liver fat and cognition

Smaller studies examined liver fat and cognition in distinct populations and designs.

The first liver-fat study

A six-month randomized trial included 50 adults with HIV and abdominal fat accumulation at baseline; 48 received at least one dose of their assigned tesamorelin or placebo. The net difference in liver lipid-to-water fraction was -2.9 percentage points. This was an imaging result: the study had no liver biopsies and did not establish long-term clinical benefit.²¹⁴

61 enrolled

In a later trial, 30 participants received tesamorelin and 30 received placebo. The treatment effect on hepatic fat fraction was -4.1 percentage points, corresponding to a 37% relative reduction. Longer-term effects on liver disease remained uncertain.²¹⁵

Trial outside HIV

A completed fatty-liver trial enrolled 51 people outside the HIV-specific population; 34 had data for the primary liver-fat analysis. The posted registry results describe liver-fat changes but give no comparative statistical test, and the dose descriptions conflict. No matching primary publication was verified among the sources behind this chapter.²¹⁶

The cognition results are mixed

A 20-week placebo-controlled trial enrolled 152 older adults, including 66 with mild cognitive impairment. Its overall cognition analysis favored tesamorelin, with the clearest result in executive function. A later six-month open-label trial in 73 adults with HIV found no significant cognitive difference between tesamorelin and standard care. These populations and study designs were different.^217,218

Later cognition pilot

A 2026 report studied 22 adults with cognition ranging from normal to mild impairment. After ten weeks, low-dose tesamorelin was not directly associated with significant changes in the measured outcomes.²¹⁹

Safety data

The same hormone pathway that produces the intended effect also explains several prescribing precautions.

5% versus 1%

The current label reports HbA1c-defined diabetes in 5% of tesamorelin recipients versus 1% with placebo. Similar average glucose values between groups do not rule out individual cases of diabetes.²⁰⁸

IGF-1 and malignancy

Active malignancy is a contraindication. A history of treated malignancy requires a separate risk assessment; it is not identical to active cancer. The effects of prolonged IGF-1 elevation are unknown, which is why the label calls for monitoring.²⁰⁸

Fluid retention and local reactions

Reported effects include swelling, joint pain, carpal tunnel symptoms and injection-site reactions. Hypersensitivity may require stopping treatment. The label reports injection-site reactions in two different summaries with different percentages, so those figures should not be treated as one interchangeable rate.²⁰⁸

Who has contraindications or population gaps

Pregnancy and disruption of the hypothalamic-pituitary axis are contraindications. Pediatric safety and effectiveness have not been established. Findings from predominantly male trial groups also do not provide equally precise estimates for every subgroup.²⁰⁸

Long-term follow-up is incomplete

Two registered studies were meant to track long-term safety and diabetic retinopathy. Both are marked terminated, with actual enrollments of 391 and 129, and neither has posted results. The registries do not say why they ended.^220,221

What spontaneous reports can tell us

Adverse-event databases collect suspected events. Reports can overlap, lack details and involve products that are hard to identify. The collected counts cannot show the proportion of users harmed or prove that tesamorelin caused an event.^222,223

Formulations and regulatory records

Approval applies to the specific medicine described by its formulation and label.

Product	What the record says
Original Egrifta	Historical 1 mg vials; the pivotal trials used 2 mg subcutaneously daily. The original presentation is listed as discontinued.208,224
Egrifta SV	2 mg vial; labeled adult dose 1.4 mg subcutaneously daily. Mean half-life was 8 minutes in the healthy-adult PK study.211
Egrifta WR	11.6 mg vial; labeled adult dose 1.28 mg subcutaneously daily. Mean half-life was 11 minutes in the healthy-adult PK study.208

Formulation amounts

WR and SV are expressly not substitutable. Their labeled doses were compared with exposure from the original formulation; vial content, administered dose and measured half-life describe different things. Preparation and storage directions belong to the exact prescribed product.^208,211

US compounding status

Tesamorelin products transitioned to biologic licenses in 2020. FDA says biological products are not eligible for the usual 503A and 503B compounding exemptions. Its separate policy for certain mixing, dilution or repackaging of licensed biologics does not make a research vial an approved substitute.^225,226

Status differs by country

The EU central application was withdrawn in 2012 after concerns about benefit and long-term safety. Canadian database entries are now cancelled, while New Zealand lists tesamorelin as Prescription. These are different regulatory actions; prescription classification alone confers no product approval.^{227,228,229,230}

Prohibited in sport

WADA names tesamorelin under S2.2.4 as prohibited at all times. It appears in the current 2026 list and the published 2027 list, which takes effect on January 1, 2027. A doping rule is separate from medicine approval.^231,232

Common questions

Answers about results, product differences, comparisons and safety.

01 What do the current labels say about dose, timing, and duration?

The labels state 1.28 mg subcutaneously once daily for Egrifta WR and 1.4 mg subcutaneously once daily for Egrifta SV; the pivotal trials used the historical original formulation at 2 mg subcutaneously daily. The current labels do not specify a clock time, food timing, cycling, or a generic restart schedule, and they say the two current products are not substitutable. These are labeled and studied exposures, not a self-use regimen; an interrupted or missed dose requires product-specific guidance from the prescriber or pharmacist.^208,211,209

02 What is known about combining tesamorelin with other peptides or weight-loss drugs?

The sources behind this chapter do not establish a controlled outcome for peptide stacks or combinations with GLP-1 medicines. The labels report a simvastatin interaction study, warn that GH can alter clearance of some CYP450-metabolized compounds, and say glucocorticoid replacement may need adjustment. Those label observations do not validate a stack, mixing method, or timing plan.^208,211

03 How long were results measured, and what happened after treatment stopped?

The pivotal trials measured the main visceral-fat outcome at 26 weeks, and extension data followed selected participants to 52 weeks. In the first trial extension, continued treatment maintained about an 18% reduction from the original baseline, while visceral fat reaccumulated after participants switched to placebo. This describes group averages from the historical formulation and does not predict an individual timeline.^213,212

04 Will less visceral fat necessarily mean weight loss or less visible belly fat?

No. Visceral fat surrounds abdominal organs, subcutaneous fat sits under the skin, and body weight combines many tissues. The current label describes tesamorelin as weight neutral, and the selected 60-person non-HIV study found a visceral-fat treatment effect of -35 cm2 while the subcutaneous-fat difference was not significant.^208,210

05 Can handling, reconstitution, or storage instructions be transferred between WR and SV?

No. Each label has product-specific preparation, concentration, storage, and administration directions, and the labels expressly say WR and SV are not substitutable. A historical trial formulation or unapproved vial does not inherit either current product's handling record.^208,211

06 How does tesamorelin compare with GLP-1 drugs, growth hormone, sermorelin, or CJC-1295?

One registry-only randomized, open-label two-week physiology study enrolled 25 adults with HIV and compared two recombinant-growth-hormone arms with a tesamorelin arm; 5 started and 3 completed the tesamorelin arm. It posted growth-hormone and clamp outcomes, but the tiny arm and short duration do not establish comparative clinical benefit. The sources behind this chapter do not supply comparable head-to-head outcomes against GLP-1 medicines, sermorelin, or CJC compounds, and a shared pathway or goal does not make their results or doses interchangeable.^208,233

07 Does the non-HIV study establish tesamorelin as a general obesity treatment?

No. The 12-month trial enrolled 60 adults selected for both abdominal obesity and reduced growth-hormone secretion, and it measured imaging and risk-marker endpoints. That study does not create a general-obesity indication or establish fewer cardiovascular events.²¹⁰

08 What do the IGF-1, cancer, and glucose warnings actually say?

Active malignancy is a contraindication, while a history of treated malignancy requires a separate risk-benefit assessment; the effects of prolonged IGF-1 elevation are unknown. The pooled label data report HbA1c-defined diabetes in 5% of tesamorelin recipients versus 1% with placebo. A 12-week trial in 53 adults with type 2 diabetes found no significant between-group difference in insulin response or glycemic control, but that short selected study does not erase the current monitoring warning.^208,234

09 Which side effects and safety limits matter most?

The labels describe fluid retention, joint pain, carpal-tunnel symptoms, glucose intolerance or diabetes, hypersensitivity, and injection-site reactions. The same WR label reports different injection-reaction percentages in its warning and pooled adverse-reaction table, so no single rate reconciles them. Long-term cardiovascular safety has not been established.^208,211

10 Where is tesamorelin currently authorized, and what does that mean for tested sport?

The FDA Purple Book lists Egrifta SV and Egrifta WR as current prescription biologics in the United States; Canadian product records are cancelled, and the EU central application was withdrawn in 2012. FDA says biologics are not eligible for the usual 503A or 503B compounding exemptions, and its 2026 warning concerns unapproved tesamorelin-labeled products rather than licensed Egrifta. The current 2026 WADA list names tesamorelin under S2.2.4 as prohibited at all times, and the published 2027 list keeps that wording when it takes effect on January 1, 2027. China's 2026 Doping Catalogue also names it for sport control; those anti-doping records are not medicine approvals. No current cash price or insurance-coverage figure was verified for this chapter.^{224,225,226,235,236,228,229,231,232,237}

11 What is known for women, pregnancy, and other special populations?

The adult indication is not restricted to men, but 86% of participants in the 412-person pivotal trial were men, so subgroup precision is uneven. Pregnancy and disruption of the hypothalamic-pituitary axis are contraindications, and pediatric safety and effectiveness have not been established. No source behind this chapter supports using the pivotal average as a pregnancy or pediatric safety estimate.^208,209

12 Do the human data establish a bodybuilding or strength benefit?

No. An exploratory secondary analysis compared 193 tesamorelin responders with 148 placebo participants and reported changes in trunk-muscle area and density on CT. Restricting the tesamorelin group to visceral-fat responders and using imaging endpoints means the result does not establish greater strength, physical function, recovery, or a bodybuilding outcome.²³⁸

13 What does the short half-life mean for the effect?

It describes measured drug exposure; the duration of fat loss and every downstream hormone effect fall outside those measurements. In separate healthy-adult label studies, mean half-life was 11 minutes after 1.28 mg Egrifta WR and 8 minutes after 1.4 mg Egrifta SV. Those records are not a head-to-head effectiveness comparison and do not support a formulation-independent 30-minute claim.^208,211

14 What is the difference between original Egrifta, Egrifta SV, and Egrifta WR?

The original 1 mg-vial presentation supplied the historical 2 mg pivotal-trial formulation and is listed as discontinued in the US Purple Book. SV is a 2 mg-vial product with a labeled 1.4 mg dose, while WR is an 11.6 mg-vial product with a labeled 1.28 mg dose; each current product was exposure-bridged to the historical formulation. Vial content, administered amount, concentration, and exposure are different measurements, and the labels say WR and SV are not substitutable.^208,211,224

15 What did the later fatty-liver trial show?

A later 12-month trial enrolled 61 people with HIV and NAFLD; 30 received tesamorelin and 30 received placebo. The hepatic-fat-fraction treatment effect was -4.1 percentage points, corresponding to a 37% relative reduction, and 35% versus 4% finished below 5% hepatic fat fraction. The investigators said longer-term effects on liver disease and histology still needed study. Separately, completed registry NCT03375788 enrolled 51 adults with NAFLD without HIV selection; 34 entered its primary liver-fat analysis, with median “percent change in hepatic fat fraction” of -5.3 versus +3.6. No comparative P value or confidence interval was posted, the intervention dose fields conflict, and no matched publication was identified, so it remains registry-only context rather than a clean efficacy estimate.^215,216