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Tesamorelin

Tier 1 · Human trials
Also known as TH9507 · Egrifta

Efficacy and safety are supported by multiple randomized, multicenter, placebo-controlled Phase III trials (LIPO-010, CTR-1011) and their extension phases in HIV-associated lipodystrophy, plus FDA approval (2010). Detailed molecular/mechanistic descriptions (hexenoyl cap, GHRHR/Gs-cAMP/JAK2-STAT5 signaling) and regulatory history derive partly from lower-tier expert/clinic sources, some corroborated by tier 1 sources. Off-label uses (somatopause, NAFLD, cognitive impairment, orthopaedic) lack supporting clinical evidence.

Half-life
Not recorded
Routes
Subcutaneous injection (abdomen)
Goals
fat loss · gh stimulation · body composition
Cost / mg
Not recorded

How it works

Tesamorelin is a synthetic, stabilized version of growth hormone-releasing hormone (GHRH), the natural brain signal that tells the pituitary gland to release growth hormone. Rather than injecting growth hormone directly, tesamorelin prompts the body to release its own growth hormone in a natural, pulsing pattern. The extra growth hormone then drives the liver to make IGF-1 and promotes the breakdown of fat (lipolysis), which is why it reduces excess visceral (deep abdominal) fat in HIV-infected patients with lipodystrophy.

Overview

Overview

Tesamorelin (developmental code TH9507, marketed as Egrifta) is a stabilized synthetic analogue of the hypothalamic peptide growth hormone-releasing hormone (GHRH). It is a 44-amino-acid peptide (molecular weight ~5135.9 Da; formula C221H366N72O67S) developed by the Canadian biotech Theratechnologies (Montreal) and supplied as the acetate salt.

Regulatory Status

Tesamorelin was approved by the U.S. FDA on 10 November 2010 under the brand name Egrifta. It is the only GHRH analogue ever approved by the FDA for human use, and the only FDA-approved therapy to reduce excess abdominal fat in people with HIV. The European Medicines Agency granted centralized approval in July 2011, but marketing authorization was withdrawn at the sponsor's request in 2014 for commercial (not safety) reasons. It is now available in the US in a 2-mg per vial formulation (Egrifta SV); the formulation is also referenced as Egrifta WR.

Approved Indication

Tesamorelin is indicated to induce and maintain a reduction of excess abdominal fat in HIV-infected patients with lipodystrophy. HIV-associated lipodystrophy is characterized by body-composition changes including lipohypertrophy with excess visceral adipose tissue (VAT), commonly associated with protease inhibitor use, which negatively affects body image and quality of life.

Mechanism

Rather than introducing exogenous human growth hormone, tesamorelin stimulates the release of the patient's own growth hormone in a natural pulsatile pattern by acting as a selective agonist at the GHRH receptor on anterior pituitary somatotrophs. The released GH drives hepatic IGF-1 synthesis and lipolysis, producing dose-dependent increases in IGF-1 and reductions in visceral fat. Because it works upstream at the pituitary, natural negative feedback is preserved.

Clinical Evidence

Efficacy was demonstrated in two randomized, multicenter, placebo-controlled Phase III trials (LIPO-010, N=412; CTR-1011, N=404), with a primary outcome of percent change in VAT at week 26. Enrollment required waist circumference ≥95 cm (males) / ≥94 cm (females), VAT >130 cm² by CT, and age 18–65.

  • Daily tesamorelin 2 mg for 26 weeks produced a significant decrease in VAT (~15% reduction) and improvement in lipids (P<0.001 vs baseline).
  • VAT reduction was sustained at ~18% over 52 weeks; a triglyceride change of about -51 mg/dL was sustained, with beneficial effects on total cholesterol and only minimal HDL decrease.
  • Subcutaneous adipose tissue and BMI were not clinically significantly affected (weight-neutral).
  • Clinical response (VAT decrease ≥8%) was achieved by approximately 70% of participants.
  • Beyond fat quantity, tesamorelin increased VAT density (+6.2 HU vs +0.3 HU placebo) and SAT density (+4.0 HU vs +0.3 HU placebo), improving fat quality.
  • Both trials showed significant improvements in some subjective body-image measures such as belly-image distress.

A separate 12-month study reported significant declines in visceral fat (median -25 cm² vs placebo +14 cm², P=0.001), hepatic fat (-4.2% vs -0.5%, P=0.01), and trunk-to-appendicular fat ratio (-0.1 vs 0.0, P=0.03), with beneficial effects and no exacerbation of glycemic control in patients on INSTI-based regimens.

Important Caveat: Reversibility

Upon discontinuation, VAT reaccumulates; effects on VAT are sustained during treatment but do not persist beyond the duration of therapy, implying that ongoing treatment is required to maintain benefit.

Off-Label and Investigational Uses

Outside its labeled indication, tesamorelin has been studied for age-related somatopause, non-alcoholic fatty liver disease (NAFLD), mild cognitive impairment, and metabolic syndrome. Supporting evidence for these is limited. A 6-month phase 2 open-label trial (N=73) showed only a non-significant trend toward improved neurocognitive performance (0.146; 95% CI -.002 to .294; P=.060) with no significant difference versus standard of care (P=.673), despite greater waist-circumference reduction (median difference -2.7 cm, P=.015). It has no supporting orthopaedic evidence, though GH secretagogues are discussed theoretically as possible adjuncts in orthopaedic injury.

Doping

Administration of tesamorelin and other GHRH synthetic analogs is prohibited by the World Anti-Doping Agency (WADA).

What the research shows

159 findings extracted from the 24 sources cited below, strongest evidence first within each group. Every one links to the source it came from.

What human studies found

Based on 49 human trial findings, 1 human study finding and 6 expert opinion findings.

  • human trialTesamorelin led to significant declines in visceral fat with median change of -25 cm2 compared to placebo +14 cm2 (P=0.001)2

  • human trialTesamorelin led to significant declines in hepatic fat with median change of -4.2% compared to placebo -0.5% (P=0.01)2

  • human trialTesamorelin led to significant declines in trunk-to-appendicular fat ratio with median change of -0.1 compared to placebo 0.0 (P=0.03)2

  • human trialTesamorelin had beneficial effects on body composition with no exacerbation of glycemic control in people on INSTI-based regimens2

  • human trialTesamorelin selectively reduced visceral fat by approximately 15% over 26 weeks and 18% over 52 weeks with no change in subcutaneous fat or BMI compared to placebo in prior Phase III trials2

  • human trialPrimary efficacy outcome for LIPO-010 and CTR-1011 was the per cent change in VAT at week 263

  • human trialSecondary efficacy outcomes included patient-reported outcomes (PROs) related to body image, specifically perceived belly size, belly appearance distress, and belly profile3

  • human trialOther relevant efficacy outcomes measured included waist circumference and quality of life3

Show 48 more findings

  • human trialTreatment of HIV patients with daily tesamorelin, a growth hormone-releasing factor analogue, for 26 weeks resulted in a significant decrease in visceral adipose tissue (VAT) and improvement in lipids4

  • human trialThe change in VAT was sustained at -18% over 52 weeks of treatment4

  • human trialChange in triglycerides was -51 mg/dl over 52 weeks of treatment4

  • human trialSimilar sustained beneficial effects were seen for total cholesterol, but high-density lipoprotein decreased minimally over 52 weeks4

  • human trialUpon discontinuation of tesamorelin, VAT reaccumulated4

  • human trialThough effects on VAT are sustained during treatment for 52 weeks, these effects do not last beyond the duration of treatment4

  • human trialAs May 2018, Theratechnologies announced that tesamorelin will enter a Phase 2b trial in patients6

  • human trialIn clinical trials in patients with HIV-associated lipodystrophy, tesamorelin therapy was not associated with de novo elevations in serum enzymes and in some studies was associated with decreases in preexisting ALT elevations7

  • human trialEfficacy of tesamorelin in the treatment of HIV-associated lipodystrophy shown in 2 randomized, multicenter, placebo-controlled trials8

  • human trialInsufficient evidence to support improved compliance with antiretroviral therapies in HIV-infected patients administered tesamorelin8

  • human trialTesamorelin reduces abdominal obesity11

  • human trialTesamorelin increases IGF-111

  • human trialTesamorelin showed a trend toward improved neurocognitive performance after 6 months in people with HIV and abdominal obesity11

  • human trialThe between-group difference in neurocognitive performance improvement was not significant between tesamorelin and standard of care groups11

  • human trialIGF-1 level increases with tesamorelin did not correlate with neurocognitive changes or waist circumference changes11

  • human trialTesamorelin group had greater reduction in waist circumference than standard of care group11

  • human trialShort-term abdominal obesity reduction with tesamorelin showed no clear benefit on neurocognitive impairment11

  • human trialPhase III clinical trials of tesamorelin were conducted prior to the introduction of integrase inhibitors (INSTIs)12

  • human trialTesamorelin 2 mg once daily led to significant declines in visceral fat compared to placebo in PWH on INSTI-based regimens12

  • human trialTesamorelin led to significant declines in hepatic fat compared to placebo12

  • human trialTesamorelin led to significant declines in trunk-to-appendicular fat ratio compared to placebo12

  • human trialOver 26 weeks, tesamorelin-treated participants showed mean VAT density increase of +6.2 (8.7) HU compared to +0.3 (4.2) HU in placebo (P < 0.0001)13

  • human trialOver 26 weeks, tesamorelin-treated participants showed mean SAT density increase of +4.0 (8.7) HU compared to +0.3 (4.8) HU in placebo (P < 0.0001)13

  • human trialTesamorelin improves VAT and SAT quality independent of changes in fat quantity in people living with HIV with central adiposity who experienced VAT quantity reductions13

  • human trialIn 2 Phase 3 clinical trials and their pooled analyses, tesamorelin was proven to significantly decrease waist circumference and visceral adipose tissue (VAT) following 26 weeks of treatment14

  • human trialBoth trials demonstrated significant improvements in some subjective body image parameters14

  • human trialBoth studies had 26-week extension phases that confirmed maintenance of VAT improvements on treatment without adverse impact on blood glucose and lipid parameters14

  • human trialLimited data support off-label uses of tesamorelin at this time14

  • human trialTesamorelin is effective in improving visceral adiposity and body image in patients with HIV-associated lipodystrophy over 26-52 weeks of treatment14

  • human trialSubcutaneous tesamorelin was effective in reducing visceral adipose tissue (VAT) in two 26-week, well designed, clinical trials in patients with HIV-associated central fat accumulation15

  • human trialTesamorelin did not affect subcutaneous adipose tissue to a clinically significant extent in the clinical trials15

  • human trialReduction in VAT was maintained in the longer term in patients who continued to receive tesamorelin until week 52 in the extension phases of the trials15

  • human trialDiscontinuation of tesamorelin therapy resulted in the reaccumulation of VAT15

  • human trialTesamorelin therapy was associated with significant improvements in other body composition measures such as trunk fat and waist circumference15

  • human trialTesamorelin therapy was associated with improvements in some body image parameters such as belly image distress15

  • human trialSubcutaneous tesamorelin was effective in reducing visceral adipose tissue (VAT) in two 26-week clinical trials in patients with HIV-associated central fat accumulation16

  • human trialTesamorelin did not affect subcutaneous adipose tissue to a clinically significant extent in the trials16

  • human trialReduction in VAT was maintained in patients who continued to receive tesamorelin until week 52 in the extension phases of the two trials16

  • human trialDiscontinuation of tesamorelin therapy resulted in reaccumulation of VAT16

  • human trialTesamorelin therapy was associated with significant improvements in trunk fat and waist circumference16

  • human trialTesamorelin therapy was associated with improvements in some body image parameters16

  • human studyTesamorelin is a long-lasting GHRH analogue that was shown effective in attenuating visceral fat and lipodystrophy in HIV-infected individuals taking highly active anti-retroviral therapy (HAART)6

  • expert opinionTesamorelin has no supporting orthopaedic evidence10

  • expert opiniontesamorelin is an approved drug by FDA (2010)19

  • expert opinionTesamorelin is the only growth hormone releasing hormone (GHRH) analogue ever approved by the FDA for human use23

  • expert opinionGreenlit in 2010 under the brand name Egrifta23

  • expert opinionThe compound was developed by the Canadian biotech Theratechnologies and received FDA approval on 10 November 2010 for the reduction of excess visceral adipose tissue (VAT) in HIV-infected patients with lipodystrophy23

  • expert opinionThe European Medicines Agency granted centralized approval in July 2011, but marketing authorization was withdrawn at the request of the sponsor in 2014 for commercial reasons (not safety)23

How it works

Based on 4 human trial findings, 1 human study finding, 13 expert opinion findings and 5 theoretical findings.

  • human trialTesamorelin is a growth hormone-releasing hormone11

  • human trialIn people with HIV who are virally suppressed, abdominal obesity is linked to neurocognitive impairment potentially due to visceral adiposity, inflammation, and reduced IGF-111

  • human trialTesamorelin is a growth hormone-releasing hormone analogue that reduces visceral fat (VAT) quantity in some people living with HIV13

  • human trialTesamorelin is a synthetic analog of human growth hormone-releasing hormone (also known as growth hormone-releasing factor) that stimulates the synthesis and release of endogenous growth hormone15

  • human studyTesamorelin is given subcutaneously and has major effects on glucose and lipid metabolism7

  • expert opinionTesamorelin is a synthetic analogue of growth hormone–releasing factor that triggers diverse metabolic effects, including lipolysis1

  • expert opinionTesamorelin is a growth hormone-releasing hormone analogue2

  • expert opinionTesamorelin is a synthetic analogue of growth hormone–releasing factor that triggers diverse metabolic effects, including lipolysis3

Show 15 more findings

  • expert opinionSynthetic analog of human growth hormone-releasing factor (GHRF)8

  • expert opinionTesamorelin stimulates the release of endogenous growth hormone (GH), a known growth factor8

  • expert opinionTesamorelin injection is a hormone similar to the one normally released from the hypothalamus gland in the brain9

  • expert opinionTesamorelin is a synthetic analogue of human growth hormone-releasing hormone that stimulates the synthesis and release of endogenous growth hormone16

  • expert opinionIt stimulates the pituitary to release endogenous growth hormone in physiological, pulsatile patterns rather than flooding the body with exogenous human growth hormone (HGH)23

  • expert opinionTesamorelin is a selective agonist at the GHRH receptor (GHRHR), a class B G protein-coupled receptor expressed predominantly on somatotroph cells in the anterior pituitary23

  • expert opinionBinding activates adenylate cyclase through Gs alpha coupling, elevating intracellular cyclic AMP and triggering the release of stored growth hormone (GH) from secretory granules23

  • expert opinionThe released GH then acts systemically, most importantly on hepatocytes, where it induces insulin-like growth factor 1 (IGF-1) synthesis via JAK2 / STAT5 signaling23

  • expert opinionBecause Tesamorelin works upstream of the pituitary rather than replacing GH directly, the resulting GH profile preserves the body's natural negative feedback23

  • expert opinionPeptides are short chains of amino acids with a unique pharmacological niche between small-molecule drugs and large proteins24

  • theoreticalTesamorelin is a synthetic 44 amino acid polypeptide analogue of growth hormone releasing hormone (GHRH)7

  • theoreticalTesamorelin activates GHRH receptors in the pituitary which leads to synthesis and release of growth hormone that acts on multiple cells of the body including hepatocytes where it stimulates production of insulin like growth factor-1 (IGF-1)7

  • theoreticaltesamorelin is a stabilized synthetic peptide analogue of the hypothalamic peptide GHRH19

  • theoreticalTesamorelin is a growth hormone secretagogue that activates IGF-1 signaling and satellite cell repair20

  • theoreticalTesamorelin is a synthetic analog of growth hormone releasing hormone (GHRH)21

Dosing

Based on 2 human trial findings, 1 human study finding and 5 expert opinion findings.

  • human trialTesamorelin 2 mg/day (subcutaneous injection) compared to placebo in randomized controlled trials3

  • human trialTesamorelin is administered subcutaneously18

  • human studyThe recommended dose is 2 mg daily given by subcutaneous injection7

  • expert opinionAdminister sub-Q into the abdomen once daily8

  • expert opinionThis medicine is given as a shot under the skin of your stomach9

  • expert opinionUse a different body area each time you give yourself a shot9

  • expert opinionDo not inject into skin areas with scar tissue, hard bumps, or bruises, or into your belly button9

  • expert opinionUse a new needle and syringe each time you inject your medicine9

How the body handles it

Based on 4 human trial findings, 2 human study findings, 2 in vitro findings, 4 expert opinion findings and 2 theoretical findings.

  • human trial2-mg per vial formulation (Egrifta SV) that is given as a 1.4-mg dose has demonstrated comparable bioavailability to the 1-mg/vial formulation (Egrifta)8

  • human trialTesamorelin increases growth hormone levels in healthy subjects18

  • human trialTesamorelin increases IGF-1 levels in healthy subjects in a dose-dependent manner18

  • human trialAge is an intrinsic factor affecting pharmacokinetics and pharmacodynamics of tesamorelin18

  • human studyTesamorelin has different pharmacokinetic characteristics in HIV-infected patients compared to healthy subjects18

  • human studyTesamorelin increases IGF-1 levels in HIV-infected patients18

  • in vitroNineteen major in vitro metabolites of tesamorelin were identified21

  • in vitroA liquid chromatography-tandem mass spectrometry method was developed to detect tesamorelin with limits of detection of 1 ng/ml or less21

Show 6 more findings

  • expert opinionThe approved formulation is the acetate salt19

  • expert opinionGHRH synthetic analogs do not appear to have been found in anti-doping samples by WADA accredited laboratories, possibly due to small concentration in urine and limited knowledge about their metabolism21

  • expert opinionNative GHRH has a plasma half life of only a few minutes because DPP-IV cleaves the first two residues on contact23

  • expert opinionThe hexenoyl cap roughly triples the plasma persistence of Tesamorelin without altering its receptor binding profile23

  • theoreticalThe N terminal portion of the molecule has been modified to improve its stability and pharmacokinetics in comparison to native GHRH7

  • theoreticalTesamorelin is a synthetic polypeptide that acts upon growth hormone producing cells in the pituitary and is generally metabolized locally by the receptor bearing cells7

Safety and side effects

Based on 12 human trial findings, 5 human study findings and 14 expert opinion findings.

  • human trialTesamorelin was well-tolerated with a similar frequency of adverse events including hyperglycemia between groups2

  • human trialChanges in glucose parameters over 52 weeks were not clinically significant4

  • human trialTesamorelin was generally well tolerated4

  • human trialThe prevalence of adverse events and serious adverse events during the extension phase was comparable with the initial phase4

  • human trialLong-term cardiovascular safety not established8

  • human trialTesamorelin was well tolerated with a similar frequency of adverse events, including hyperglycemia, between tesamorelin and placebo groups12

  • human trialTesamorelin was generally well tolerated with treatment-emergent serious adverse events occurring in less than 4% of patients during 26 weeks of therapy15

  • human trialMost serious adverse events were injection-site reactions or events known to be associated with growth hormone therapy such as arthralgia, headache and peripheral edema15

Show 23 more findings

  • human trialTreatment-emergent serious adverse events occurred in <4% of patients during 26 weeks of therapy16

  • human trialMost treatment-emergent serious adverse events were injection-site reactions or events known to be associated with growth hormone therapy such as arthralgia, headache and peripheral oedema16

  • human trialImmunogenicity affects the pharmacokinetics of tesamorelin18

  • human trialTesamorelin has been studied for drug-drug interactions18

  • human studyTesamorelin has not been linked to serum aminotransferase elevations during therapy or to instances of clinically apparent acute liver injury7

  • human studySide effects include injection site reactions, itching, arthralgia, myalgia and peripheral edema7

  • human studyTesamorelin raises IGF-1 levels and monitoring for elevations during therapy is recommended7

  • human studyPotential rare adverse events include stimulation of malignant tumor growth, glucose intolerance, diabetes and hypersensitivity reactions7

  • human studyInstances of clinically apparent liver injury attributable to tesamorelin use have not been reported7

  • expert opinionMonitor patients periodically during treatment for development of impaired glucose tolerance or diabetes8

  • expert opinionMonitor patients with diabetes at regular intervals for development or worsening of retinopathy8

  • expert opinionMonitor for signs and symptoms of hypersensitivity reactions (pruritus, erythema, flushing, urticaria, rash)8

  • expert opinionContraindicated in patients with disruption of the hypothalamic-pituitary axis due to hypophysectomy, hypopituitarism, pituitary tumor/surgery, head irradiation, or head trauma8

  • expert opinionContraindicated in active malignancy8

  • expert opinionContraindicated in pregnant women8

  • expert opinionShould not be used in patients with pituitary gland tumor or surgery9

  • expert opinionShould not be used in patients with active or history of cancer9

  • expert opinionShould not be used in patients with allergy to mannitol history9

  • expert opinionUse with caution in patients with breathing problems, lung disease, carpal tunnel syndrome, diabetes, edema, heart surgery history, retinopathy, stomach surgery history, or trauma9

  • expert opinionSafety and efficacy have not been established in children9

  • expert opinionPotential limitations for its use include high cost and lack of long-term safety and adherence data14

  • expert opinionAdministration of tesamorelin and other GHRH synthetic analogs is prohibited by the World Anti-Doping Agency (WADA)21

  • expert opinionTesamorelin has undergone a rigorous approval process that evaluates both safety and efficacy24

What people use it for

Based on 9 human trial findings, 9 human study findings, 6 expert opinion findings and 1 theoretical finding.

  • human trialTesamorelin is indicated for treatment of excess visceral adipose tissue (VAT) in treatment-experienced adult HIV-infected patients with lipodystrophy1

  • human trialTesamorelin is the only FDA-approved therapy to treat abdominal fat accumulation in people with HIV2

  • human trialTesamorelin is a growth hormone releasing factor (GRF) analog used to reduce excessive abdominal fat in HIV patients who have developed lipodystrophy5

  • human trialHas a weight neutral effect8

  • human trialClinical response to tesamorelin was defined as VAT decrease ≥8%, achieved by approximately 70% of participants13

  • human trialTesamorelin is a growth hormone releasing factor analogue approved by the Food and Drug Administration in November 2010 for the treatment of lipodystrophy associated with HIV infection14

  • human trialTesamorelin is the first and only treatment indicated for the reduction of excess abdominal fat in patients with HIV-associated lipodystrophy15

  • human trialtesamorelin (Egrifta; Theratechnologies/EMD Serono), a growth hormone-releasing factor analogue, was approved by the US Food and Drug Administration for the reduction of excess abdominal fat in HIV-infected patients with lipodystrophy17

Show 17 more findings

  • human trialTesamorelin is a growth hormone-releasing hormone (GHRH) analog indicated to induce and maintain a reduction of excess abdominal fat in HIV-infected patients with lipodystrophy18

  • human studyHuman immunodeficiency virus (HIV)–associated lipodystrophy is characterized by body composition changes, including lipohypertrophy with excess visceral adipose tissue (VAT)1

  • human studyUse of protease inhibitors is commonly associated with the development of lipohypertrophy1

  • human studyExcess VAT negatively affects patients' body image and quality of life (QoL)1

  • human studyHIV–associated lipodystrophy is characterized by body composition changes, including lipohypertrophy3

  • human studyProtease inhibitors are commonly associated with the development of lipohypertrophy3

  • human studyTesamorelin is an analog of growth hormone-releasing hormone used as a subcutaneous treatment to reduce excess abdominal fat in HIV-infected patients with lipodystrophy6

  • human studyTesamorelin is a synthetic growth hormone releasing hormone analogue used in the treatment of visceral adiposity in human immunodeficiency virus (HIV) infected patients with lipodystrophy7

  • human studyTesamorelin was approved for use in the United States as therapy to reduce excess abdominal fat in HIV-infected patients with antiviral therapy-related lipodystrophy in 20107

  • human studyIt is used to reduce excess fat (lipodystrophy) in the stomach area in patients with human immunodeficiency virus (HIV) infection9

  • expert opinionTesamorelin may sometimes be given at home to patients who do not need to be in a hospital or clinic9

  • expert opinionTesamorelin is approved for treating HIV-associated lipodystrophy10

  • expert opinionTesamorelin is the only FDA-approved therapy to treat abdominal fat accumulation in people with HIV12

  • expert opinionTesamorelin is the first and only treatment indicated for the reduction of excess abdominal fat in patients with HIV-associated lipodystrophy16

  • expert opinionOutside of that labeled indication, Tesamorelin has been studied for age-related somatopause, non-alcoholic fatty liver disease (NAFLD), mild cognitive impairment and metabolic syndrome23

  • expert opinionTesamorelin (Egrifta) is a peptide marketed direct to patients24

  • theoreticalGrowth hormone secretagogues like tesamorelin are emerging as promising adjuncts in the management of orthopaedic injuries20

Other findings

Based on 1 human trial finding and 1 expert opinion finding.

  • human trialBrand name is Egrifta5

  • expert opinionThe molecular weight is approximately 5135.9 Da23

Points of contention

Where the evidence is unsettled, thin, or says less than the popular claim — worth knowing before you draw conclusions.

Limited evidence

VAT benefits reverse after stopping treatment.

Multiple trial sources report that upon discontinuation of tesamorelin, VAT reaccumulated, and effects on VAT do not last beyond the duration of treatment, implying ongoing therapy is required to maintain the benefit.

Limited evidence

Long-term cardiovascular safety and adherence data are lacking.

Sources note long-term cardiovascular safety is not established, and cite high cost plus lack of long-term safety and adherence data as limitations for use.

Limited evidence

Neurocognitive benefit was not demonstrated.

A phase 2 trial (Effects of Tesamorelin on Neurocognitive Impairment in Persons With HIV and Abdominal Obesity.) found only a non-significant trend toward improved neurocognitive performance with tesamorelin (P=.060) and no significant between-group difference versus standard of care (P=.673), despite significant waist circumference reduction.

Limited evidence

Off-label and orthopaedic uses lack supporting evidence.

Tesamorelin: a growth hormone-releasing factor analogue for HIV-associated lipodystrophy. states limited data support off-label uses; Injectable Peptide Therapy: A Primer for Orthopaedic and Sports Medicine Physicians. states tesamorelin has no supporting orthopaedic evidence; while Therapeutic Peptides in Orthopaedics: Applications, Challenges, and Future Directions. (tier 2) frames GH secretagogues as promising adjuncts for orthopaedic injury on a theoretical basis. Tesamorelin Dosing Guide: GHRH Analogue Research Protocols lists somatopause, NAFLD, cognitive impairment and metabolic syndrome only as areas studied.

Single source

Detailed molecular/mechanistic and regulatory-history details come from lower-tier sources.

Molecular weight (~5135.9 Da), hexenoyl cap tripling plasma persistence, GHRHR/Gs-cAMP/JAK2-STAT5 signaling detail, and the 2014 EMA withdrawal for commercial reasons derive largely from tier 3 blog/clinic sources (Tesamorelin Dosing Guide: GHRH Analogue Research Protocols, The Ultimate Guide to Tesamorelin | Las Vegas | Sky Health); some mechanistic detail is corroborated by tier 1 Tesamorelin - LiverTox - NCBI Bookshelf.

Limited evidence

INSTI-era efficacy data come from a small trial.

Prior pivotal Phase III trials predated integrase inhibitors; the INSTI-era evidence (Efficacy and Safety of Tesamorelin in People with HIV on Integrase Inhibitors - PMC, Efficacy and safety of tesamorelin in people with HIV on integrase inhibitors.) comes from a small 12-month study (61 participants, with only 15 tesamorelin and 16 placebo completers), limiting the strength of the conclusion that glycemic control is not worsened on INSTI regimens.

Contested

Reference sources list two different CAS numbers for tesamorelin.

The research-oriented guide "Tesamorelin Dosing Guide: GHRH Analogue Research Protocols" lists CAS 218949-48-5 for tesamorelin, while the NCBI LiverTox entry "Tesamorelin" lists CAS 901758-09-6, pairing that number with a molecular formula that includes an acetate component (C221-H366-N72-O67-S·(C2-H4-O2)x), i.e., the acetate salt form.

What you may have heard

A widely repeated claim that tesamorelin is the only GHRH analogue the FDA has ever approved overlooks an earlier approved GHRH-class drug.

The sweeping statement that tesamorelin is 'the only growth hormone releasing hormone (GHRH) analogue ever approved by the FDA for human use' comes from a single commercial blog, the Tesamorelin Dosing Guide: GHRH Analogue Research Protocols. Sermorelin — another GHRH-class peptide, being the 29-amino-acid biologically active fragment of GHRH — was FDA-approved in the 1990s under the brand name Geref for the diagnosis and treatment of growth hormone deficiency in children, though that branded product is no longer commercially manufactured. What the clinical literature actually supports is the narrower statement that tesamorelin is the only FDA-approved therapy for reducing excess abdominal fat in people with HIV-associated lipodystrophy.

Inconsistency

Recommended dose stated as 2 mg daily, but Egrifta SV described as "given as a 1.4-mg dose," and old vial as 1 mg / 1.1 …

The profile simultaneously says the recommended dose is 2 mg daily (claim 56), that the SV formulation is given as 1.4 mg with bioavailability comparable to the 1-mg vial (claim 24), and that the lyophilized powder contains 1.1 mg acetate (claim 75). A reader cannot reconcile whether the patient receives 1 mg, 1.4 mg, or 2 mg of active tesamorelin. This needs disambiguation (free-base vs acetate salt, and formulation-specific delivered dose).

Other

The headline 52-week efficacy figures are within-group changes from baseline, not placebo-controlled between-group differences.

The sustained 52-week results — an 18% reduction in visceral adipose tissue and a 51 mg/dL fall in triglycerides, each reported at P<0.001 — are given in "Long-term safety and effects of tesamorelin, a growth hormone-releasing factor analogue, in HIV patients with abdominal fat accumulation" as changes versus baseline within the tesamorelin-treated group rather than as differences against placebo. This matters because a within-group change over time reflects the trajectory of treated patients, not the effect attributable to tesamorelin relative to placebo. Notably, the extension phase was not uncontrolled: at week 26 patients were re-randomized into controlled arms (continuing tesamorelin, switched to placebo, or newly started on tesamorelin), so a comparator did exist — but the widely cited sustained-effect numbers are nonetheless quoted as within-group versus-baseline statistics.

What you may have heard

Describing tesamorelin as "generally metabolized locally by the receptor-bearing cells" is a vague characterization not backed by clear pharmacokinetic data.

The LiverTox monograph (Tesamorelin) states in its mechanism-of-injury section that tesamorelin "is generally metabolized locally by the receptor bearing cells," but this phrasing is imprecise about how the peptide is actually cleared from the body. Native growth hormone-releasing hormone is rapidly cleaved by dipeptidyl peptidase-IV (DPP-IV) within minutes, and tesamorelin's defining N-terminal modification was engineered specifically to resist that enzymatic degradation and prolong its plasma persistence (Tesamorelin Dosing Guide: GHRH Analogue Research Protocols; The Ultimate Guide to Tesamorelin). The detailed metabolism of tesamorelin itself remains incompletely characterized, with in vitro work identifying numerous metabolites while noting limited knowledge of how these analogues are metabolized (Advances in the detection of growth hormone releasing hormone synthetic analogs).

Other

No numeric half-life given, though a well-characterized value exists.

Tesamorelin's plasma half-life (~26–38 min in reported PK studies) supports the once-daily dosing rationale (short pulse to preserve pulsatility). Stating only that it "roughly triples" GHRH persistence leaves the reader without the actual figure that justifies daily administration.

What you may have heard

12-month INSTI-era findings presented with firm P-values despite very small completer numbers.

The stated caveat notes the INSTI study had only ~15 tesamorelin and ~16 placebo completers, yet the overview reports median VAT/hepatic-fat/ratio changes with P-values as robust confirmation that glycemic control is not worsened. The small n should be surfaced in the prose, not only the caveat block.

Contested

Injection sites should be rotated using a new needle and syringe each time, avoiding scar tissue, hard bumps, bruises, o…

While the source material supports most of the statement's components individually—including rotating injection sites, using a new needle and syringe each time, and avoiding scar tissue, hard bumps, bruises, and the belly button—the source does not explicitly state that rotation should be done 'using a new needle and syringe each time' as a single integrated instruction. The source lists these as separate guidance items: 'Use a different body area each time you give yourself a shot' and separately 'Use a new needle and syringe each time you inject your medicine.' The statement combines these into one directive about rotation that is not explicitly stated together in the source material in this exact formulation.

Inconsistency

Tesamorelin appears in reference databases under two different CAS registry numbers, which is not a real inconsistency.

A US National Library of Medicine record (LiverTox) lists tesamorelin under CAS 901758-09-6 with a molecular formula that carries an added acetate component, while a vendor research dosing guide lists CAS 218949-48-5 for the plain 44-amino-acid peptide (molecular weight ~5135.9 Da). The two numbers reflect the free peptide versus its acetate salt — the acetate form is what is actually supplied as the drug — rather than a contradiction. The core peptide formula, C221H366N72O67S, is consistent across chemical-structure databases.

Contested

Tesamorelin was approved by the U.S. FDA in 2010 following review of its safety and efficacy for its labeled indication;…

The source material confirms that tesamorelin has undergone a rigorous approval process evaluating safety and efficacy, and that it is marketed direct to patients. However, the source does not specify the year 2010 as the FDA approval date, nor does it address whether the label characterizes the product's marketing or the approval process. The statement makes specific claims about the approval year and label characterization that are not present in the provided source material.

Single source

The one source cited for this claim confirms tesamorelin went through a rigorous approval process but never states the 2010 date or describes what the label says.

Safety and Efficacy of Approved and Unapproved Peptide Therapies for Musculoskeletal Injuries and Athletic Performance., a tier-3 narrative review, states only that tesamorelin (Egrifta) is a peptide marketed direct to patients and that it underwent a rigorous approval process evaluating both safety and efficacy. It does not specify the November 2010 FDA approval date, nor does it make any statement about whether the label characterizes the product's marketing or the approval process. Those elements of the claim rest on no cited source here and cannot be verified against Safety and Efficacy of Approved and Unapproved Peptide Therapies for Musculoskeletal Injuries and Athletic Performance..

Using it with other compounds

Check a stack
  • TirzepatideComplementary

    Worth caution

    Tirzepatide's dual GIP/GLP-1 action reduces fat mass and improves insulin sensitivity through gut-hormone receptors, distinct from tesamorelin's GH axis. The two can converge on visceral/metabolic fat loss, and tirzepatide's insulin-sensitizing effect may counter GH-induced glucose elevation, but blood glucose still warrants monitoring on the combination.

    Tier 4Theoretical — not established

    Shares lipolysis

  • MK-677Same downstream effect

    Worth caution

    Tesamorelin is a stabilized GHRH analog that raises GH/IGF-1 through the GHRH receptor, distinct from MK-677's ghrelin-receptor pathway. Both feed the same GH/IGF-1 axis, so they can be additive on GH output. Note a practical tension: tesamorelin is used specifically to reduce visceral fat, whereas MK-677 raises appetite and can promote fluid retention and insulin resistance, which may partly counter the body-composition goal.

    Tier 3Largely anecdotal — commonly discussed

    Timing Monitor fasting glucose/insulin, since both GH-raising agents plus MK-677's appetite drive can worsen insulin sensitivity.

    Shares GH axis · IGF1 signaling · lipolysis

  • SermorelinSame mechanism

    Worth caution

    Tesamorelin is also a GHRH-receptor agonist working through the identical Gs/cAMP pathway to release endogenous GH. Combining it with sermorelin is redundant — both compete for the same receptor and effect, so you gain little over choosing the stronger/more targeted single agent (tesamorelin is the visceral-fat specialist).

    Tier 3Largely anecdotal — commonly discussed

    Shares GH axis · lipolysis · IGF1 signaling · cAMP PKA

  • KlothoStack with caution

    Worth caution

    Tesamorelin dose-dependently elevates IGF-1 via GH release, while Klotho tends to suppress IGF-1/insulin signaling as part of its longevity effects. The opposing directions on IGF-1 mean this is a mechanistic tension to be aware of if Klotho is being used for anti-senescence goals, even though tesamorelin's fat-loss benefit is unrelated.

    Tier 4Theoretical — not established
    What the research doesn't establish
    The claim of an opposing effect on IGF-1 is not established: Tesamorelin raises IGF-1 through GH release, but Klotho is not shown to suppress IGF-1/insulin signaling. Klotho's documented actions on the IGF-1/insulin axis point toward modulation or improved insulin sensitivity, so a directional conflict between the two on IGF-1 has not been demonstrated.

    Shares IGF1 signaling

  • AOD-9604Complementary

    May be complementary

    Both push fat loss but by different routes: tesamorelin raises endogenous growth hormone via the GHRH receptor, while AOD-9604 stimulates fat breakdown directly in fat cells (cAMP rise, hormone-sensitive lipase) without acting on the GH receptor. Because their entry points differ, they can reinforce each other on the same goal of reducing (especially visceral) fat.

    Tier 3Largely anecdotal — commonly discussed

    Timing No strict separation needed; both are commonly dosed on an empty stomach/subcutaneously.

    Shares lipolysis · cAMP PKA

  • CJC-1295Same mechanism

    Worth caution

    Tesamorelin is also a stabilized GHRH analog acting on the same GHRH-R/cAMP pathway to raise GH and IGF-1. Combining it with CJC-1295 stacks two drugs doing the identical job, which is redundant and could over-drive IGF-1 without adding a distinct benefit. Choose one GHRH agent for a given goal.

    Tier 3Largely anecdotal — commonly discussed

    Timing Avoid running two GHRH analogs at once; select one.

    Shares GH axis · IGF1 signaling · cAMP PKA

  • Follistatin-344Complementary

    May be complementary

    Tesamorelin raises GH/IGF-1 and preferentially strips visceral fat, while Follistatin adds muscle mass and reduces adiposity by blocking myostatin. Their combined effect leans toward improved body composition (more lean mass, less fat) through distinct pathways.

    Tier 4Theoretical — not established

    Shares IGF1 signaling

  • MOTS-cComplementary

    No documented conflict

    Both reduce adiposity, especially visceral and hepatic fat, but through unrelated mechanisms: tesamorelin raises GH/IGF-1 to drive lipolysis, while MOTS-c acts through AMPK-driven metabolism and adipose browning. These non-overlapping fat-loss pathways can complement each other for body-composition goals.

    Tier 4Theoretical — not established

    Shares lipolysis

  • SemaglutideComplementary

    Worth caution

    Both reduce fat but by unrelated mechanisms — semaglutide via appetite/energy-intake reduction and tesamorelin via GH-driven lipolysis targeting visceral and liver fat. They can be complementary for body-composition goals, but growth hormone tends to raise blood glucose and lower insulin sensitivity, which works against semaglutide's glycemic benefit, so blood sugar should be monitored.

    Tier 4Theoretical — not established

    Shares lipolysis

  • IpamorelinSame downstream effect

    May be complementary

    Tesamorelin is a stabilized GHRH analog acting on the GHRH receptor — a distinct mechanism from ipamorelin's ghrelin receptor — but both raise GH/IGF-1 and support fat loss. Combining a GHRH-side driver with ipamorelin's ghrelin-side amplification produces a larger GH pulse, and tesamorelin's specific strength in reducing visceral fat can complement ipamorelin's reported lipolysis for body-composition goals.

    Tier 2Supported by animal / early studies

    Timing Administer together on an empty stomach; nighttime dosing aligns with natural GH pulses.

    Shares GH axis · IGF1 signaling · cAMP PKA · lipolysis

  • HexarelinSame downstream effect

    May be complementary

    Tesamorelin is a stabilized GHRH analog; hexarelin is a GHS-R1a secretagogue. They act on distinct receptors that both drive pituitary GH release, so combined they can produce a larger, more physiologic GH/IGF-1 response — with tesamorelin adding a documented visceral-fat-lowering effect. Monitor IGF-1 since two upstream drivers stacking can push it higher than intended.

    Tier 2Supported by animal / early studies

    Timing Co-inject on an empty stomach; keep IGF-1 in a sensible range with periodic monitoring.

    Shares GH axis · IGF1 signaling · lipolysis

  • RetatrutideComplementary

    Worth caution

    Tesamorelin reduces visceral and hepatic fat by stimulating endogenous growth hormone (GHRH-receptor pathway) — a completely different route from retatrutide's receptor set, yet both reduce liver/visceral fat and improve lipids. They converge on the same physiological output (fat reduction) via separate upstream mechanisms, making them complementary; monitor glucose since GH can nudge insulin resistance while retatrutide improves it.

    Tier 4Theoretical — not established

    Shares lipolysis

Safety and side effects

Safety and Tolerability

Across the pivotal Phase III trials and extension phases, tesamorelin was generally well tolerated. Treatment-emergent serious adverse events occurred in less than 4% of patients during 26 weeks of therapy, most commonly injection-site reactions or events associated with GH therapy such as arthralgia, headache, and peripheral edema. In the extension trial, the overall discontinuation rate was 18.7%, with adverse-event frequency comparable to the initial phase.

Common Side Effects

  • Injection-site reactions
  • Itching (pruritus)
  • Arthralgia and myalgia
  • Peripheral edema

Metabolic Monitoring

  • Tesamorelin raises IGF-1 levels; monitoring for IGF-1 elevations during therapy is recommended.
  • Patients should be monitored periodically for impaired glucose tolerance or diabetes. In trials, glucose parameter changes over 52 weeks were not clinically significant and similar to those at 26 weeks; hyperglycemia frequency was similar between groups, including in patients on INSTI-based regimens.
  • Diabetic patients should be monitored for development or worsening of retinopathy.

Liver

Tesamorelin has not been linked to serum aminotransferase elevations or clinically apparent acute liver injury; in some studies it was associated with decreases in preexisting ALT elevations (liver injury likelihood score E, unlikely cause).

Hypersensitivity

Monitor for signs and symptoms of hypersensitivity reactions (pruritus, erythema, flushing, urticaria, rash). The formulation contains mannitol (55 mg per dose); it should not be used in patients with mannitol allergy.

Contraindications

  • Disruption of the hypothalamic-pituitary axis (hypophysectomy, hypopituitarism, pituitary tumor/surgery, head irradiation, or head trauma)
  • Active malignancy
  • Pregnancy

Cautions

Use with caution in patients with breathing problems, lung disease, carpal tunnel syndrome, diabetes, edema, history of heart surgery, retinopathy, history of stomach surgery, or trauma. Potential rare adverse events include stimulation of malignant tumor growth, glucose intolerance, diabetes, and hypersensitivity reactions.

Limitations

  • Long-term cardiovascular safety has not been established.
  • Safety and efficacy have not been established in children.
  • Immunogenicity affects pharmacokinetics, and age is an intrinsic factor affecting pharmacokinetics/pharmacodynamics.
  • High cost plus lack of long-term safety and adherence data are cited as practical limitations.

Reconstitution and handling

Formulation

Tesamorelin is supplied as a lyophilized powder (as tesamorelin acetate) requiring reconstitution before subcutaneous injection. The marketed lyophilized powder dose contains 1.1 mg tesamorelin acetate, and the formulation contains mannitol (55 mg per dose). Since 2019, only the 2-mg per vial formulation (Egrifta SV) is available in the US; given as a 1.4-mg dose it demonstrated comparable bioavailability to the older 1-mg/vial formulation (Egrifta). It is provided in two forms with different dosages (Egrifta SV and Egrifta WR).

Dosing

  • The recommended dose is 2 mg daily by subcutaneous injection.
  • It is administered subcutaneously into the abdomen once daily.
  • In healthy-subject studies, tesamorelin was tested at 1 mg and 2 mg doses.

Administration Notes

  • Rotate injection sites, using a new needle and syringe each time.
  • Avoid injecting into scar tissue, hard bumps, bruises, or the belly button.
  • Tesamorelin may sometimes be given at home to patients who do not need to be in a hospital or clinic.

Practical Consideration

Because VAT reaccumulates after discontinuation and benefits do not persist beyond treatment, ongoing daily administration is required to maintain the reduction in abdominal fat.

Sources

Ordered by evidence quality — the strongest first.

  1. Clinical Review Report: Tesamorelin (Egrifta) - NCBI Bookshelf(opens in a new tab)
    Tier 1Web · ncbi.nlm.nih.gov
  2. Efficacy and Safety of Tesamorelin in People with HIV on Integrase Inhibitors - PMC(opens in a new tab)
    Tier 1Web · pmc.ncbi.nlm.nih.gov
  3. Executive Summary - Clinical Review Report: Tesamorelin (Egrifta) - NCBI Bookshelf(opens in a new tab)
    Tier 1Web · ncbi.nlm.nih.gov
  4. Long-term safety (52 weeks) and effects of tesamorelin, a growth hormone-releasing factor analogue, in HIV patients with abdominal fat accumulation [BASIC SCIENCE](opens in a new tab)
    Tier 1Web · natap.org
  5. Tesamorelin(opens in a new tab)
    Tier 1Web · go.drugbank.com
  6. Tesamorelin - an overview | ScienceDirect Topics(opens in a new tab)
    Tier 1Web · sciencedirect.com
  7. Tesamorelin - LiverTox - NCBI Bookshelf(opens in a new tab)
    Tier 1Web · ncbi.nlm.nih.gov
  8. Tesamorelin Monograph for Professionals - Drugs.com(opens in a new tab)
    Tier 1Web · drugs.com
  9. Tesamorelin (subcutaneous route) - Side effects & dosage(opens in a new tab)
    Tier 1Web · mayoclinic.org · 2026
  10. Injectable Peptide Therapy: A Primer for Orthopaedic and Sports Medicine Physicians.(opens in a new tab)
    Tier 1PubMed · pubmed.ncbi.nlm.nih.gov · 2026
  11. Effects of Tesamorelin on Neurocognitive Impairment in Persons With HIV and Abdominal Obesity.(opens in a new tab)
    Tier 1PubMed · pubmed.ncbi.nlm.nih.gov · 2025
  12. Efficacy and safety of tesamorelin in people with HIV on integrase inhibitors.(opens in a new tab)
    Tier 1PubMed · pubmed.ncbi.nlm.nih.gov · 2024
  13. Tesamorelin improves fat quality independent of changes in fat quantity.(opens in a new tab)
    Tier 1PubMed · pubmed.ncbi.nlm.nih.gov · 2021
  14. Tesamorelin: a growth hormone-releasing factor analogue for HIV-associated lipodystrophy.(opens in a new tab)
    Tier 1PubMed · pubmed.ncbi.nlm.nih.gov · 2012
  15. Spotlight on tesamorelin in HIV-associated lipodystrophy.(opens in a new tab)
    Tier 1PubMed · pubmed.ncbi.nlm.nih.gov · 2011
  16. Tesamorelin: a review of its use in the management of HIV-associated lipodystrophy.(opens in a new tab)
    Tier 1PubMed · pubmed.ncbi.nlm.nih.gov · 2011
  17. Tesamorelin.(opens in a new tab)
    Tier 1PubMed · pubmed.ncbi.nlm.nih.gov · 2011
  18. CLINICAL PHARMACOLOGY AND BIOPHARMACEUTICS REVIEW(S)(opens in a new tab)
    Tier 1Web · accessdata.fda.gov · 2009
  19. tesamorelin | Ligand page | IUPHAR/BPS Guide to PHARMACOLOGY(opens in a new tab)
    Tier 2Web · guidetopharmacology.org
  20. Therapeutic Peptides in Orthopaedics: Applications, Challenges, and Future Directions.(opens in a new tab)
    Tier 2PubMed · pubmed.ncbi.nlm.nih.gov · 2026
  21. Advances in the detection of growth hormone releasing hormone synthetic analogs.(opens in a new tab)
    Tier 2PubMed · pubmed.ncbi.nlm.nih.gov · 2021
  22. Tesamorelin update.(opens in a new tab)
    Tier 2PubMed · pubmed.ncbi.nlm.nih.gov · 2010
  23. Tesamorelin Dosing Guide: GHRH Analogue Research Protocols(opens in a new tab)
    Tier 3Web · parahealth.de
  24. Safety and Efficacy of Approved and Unapproved Peptide Therapies for Musculoskeletal Injuries and Athletic Performance.(opens in a new tab)
    Tier 3PubMed · pubmed.ncbi.nlm.nih.gov · 2026

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