Research Applications
HIV-Associated Lipodystrophy (Approved Indication)
Tesamorelin (Egrifta) is FDA-approved for reducing excess abdominal fat in HIV-infected patients. Clinical trials (Phase 3: LIPO-010, LIPO-012) demonstrated 15-20% reduction in visceral adipose tissue (VAT) measured by CT scan, improved trunk fat ratio, and improved patient-reported body image outcomes.
MASH/NASH (Metabolic-Associated Steatohepatitis)
Tesamorelin is in Phase 2/3 clinical trials for NASH. Preliminary results show significant reduction in hepatic fat fraction (measured by MRI-PDFF), improved liver fibrosis markers, and reduced hepatic inflammation. This represents a potentially major new indication.
Cognitive Function and Aging
Clinical trials at Harvard/Massachusetts General Hospital have investigated tesamorelin for cognitive improvement in healthy aging adults and early MCI. Results show improved verbal memory, executive function, and connectivity in prefrontal cognitive networks, attributed to GH/IGF-1-mediated neuroplasticity.
General Visceral Adiposity
Research explores tesamorelin for visceral fat reduction in non-HIV populations, including metabolic syndrome and age-related visceral adiposity.
Peripheral Neuropathy
Studies suggest tesamorelin may improve peripheral nerve function through IGF-1-mediated neurotrophic effects, relevant to diabetic neuropathy and HIV-associated neuropathy.
Mechanism of Action
GHRH Receptor Agonism
Tesamorelin binds to and activates the GHRH receptor (GHRH-R) on pituitary somatotroph cells with full agonist activity equivalent to native GHRH. Receptor activation stimulates the Gαs-adenylyl cyclase-cAMP-PKA cascade, driving GH gene transcription and GH granule exocytosis.
Physiological GH Pulse Amplification
Like sermorelin, tesamorelin amplifies endogenous GH pulses while preserving pulsatile secretion patterns and somatostatin feedback regulation. The resulting GH increase is physiological in character, producing IGF-1 elevations within the normal range for young adults.
Visceral Fat Reduction
The primary therapeutic effect — selective visceral fat reduction — is mediated through GH-stimulated lipolysis. GH activates hormone-sensitive lipase in adipocytes via JAK2-mediated signaling, preferentially mobilizing visceral adipose tissue (which has higher GH receptor density than subcutaneous fat). Visceral fat reductions of 15-20% have been demonstrated in clinical trials.
Hepatic Fat Reduction
Tesamorelin reduces hepatic steatosis (liver fat) through GH-mediated enhancement of hepatic fatty acid oxidation and reduced de novo lipogenesis. This effect is mediated through GH receptor activation in hepatocytes, stimulating CPT-1 expression and mitochondrial beta-oxidation.
Preserved Somatostatin Feedback
Unlike exogenous GH administration, tesamorelin preserves normal hypothalamic-pituitary feedback mechanisms. Somatostatin continues to regulate GH secretion, preventing supraphysiological GH levels and providing an inherent safety margin.
Biological Pathways
cAMP/PKA/CREB Somatotroph Signaling
GHRH-R activation generates cAMP through Gαs-adenylyl cyclase coupling. PKA phosphorylates CREB, driving GH1 gene transcription. PKA also phosphorylates calcium channels, enabling calcium influx and GH granule exocytosis.
GH/JAK2/STAT5/IGF-1 Axis
Released GH binds hepatic GH receptors, activating JAK2 which phosphorylates STAT5b. Nuclear STAT5b drives IGF-1 gene transcription. IGF-1 mediates many of GH's metabolic and anabolic effects through PI3K/Akt and MAPK signaling.
GH/HSL Lipolytic Pathway
In adipocytes, GH activates JAK2 which phosphorylates hormone-sensitive lipase (HSL) and perilipin, enabling triglyceride hydrolysis. This lipolytic pathway preferentially targets visceral adipose tissue, which expresses higher levels of GH receptor and HSL.
GH/CPT-1 Hepatic Fat Oxidation
In hepatocytes, GH signaling upregulates carnitine palmitoyltransferase-1 (CPT-1), the rate-limiting enzyme for mitochondrial fatty acid import and oxidation. This reduces hepatic triglyceride content and ameliorates fatty liver disease.
Dosage Information
Calculation Results
Syringe Fill Level (100u syringe)
Protocols
No protocols featuring this peptide yet.
Browse All ProtocolsStability & Storage
Tesamorelin (Egrifta) is supplied commercially as a lyophilized powder (1 mg or 2 mg vials) with diluent for reconstitution. Store the lyophilized product at controlled room temperature (20-25°C). The commercial product has a shelf life of 2 years.
Reconstitute with the provided sterile water diluent. Swirl gently until completely dissolved — do not shake. The reconstituted solution should be used immediately after preparation and should not be stored.
The trans-3-hexenoic acid modification protects the N-terminal tyrosine from DPP-4 enzymatic cleavage, significantly extending the peptide's bioactive half-life compared to native GHRH. The methionine at position 27 is susceptible to oxidation — avoid exposure to strong oxidizing conditions.
Side Effects & Precautions
Injection Site Reactions (Most Common)
Erythema, pruritus, pain, swelling, and irritation at injection sites are the most frequently reported adverse effects (up to 25% of patients). Reactions are generally mild to moderate and tend to decrease with continued use.
Arthralgia (Joint Pain)
Joint pain occurs in approximately 13% of patients, attributed to GH-mediated effects on connective tissues. Usually mild and manageable.
Peripheral Edema
Mild fluid retention in extremities occurs in 6-8% of patients, a class effect of GH stimulation. Typically resolves over the first weeks of treatment.
Myalgia (Muscle Pain)
Muscle aches reported in approximately 5% of patients, usually mild and transient.
Paresthesia
Numbness or tingling (3-4%), typically in extremities, related to GH-mediated fluid effects on peripheral nerves.
Carpal Tunnel Syndrome
Reported in 2-3% of patients, a recognized complication of GH excess. Symptoms resolve with dose reduction or discontinuation.
Hyperglycemia
GH-mediated insulin resistance may modestly increase fasting glucose. Patients with pre-diabetes or diabetes should monitor glucose levels during treatment.
Hypersensitivity Reactions
Rare allergic reactions including urticaria and pruritus have been reported. Tesamorelin is contraindicated in patients with known hypersensitivity to GHRH or mannitol (excipient).
Research Use Only. This information is for educational and research purposes only. Not intended for medical advice or self-medication.
Regulatory Status
Tesamorelin (Egrifta/Egrifta SV) is FDA-approved (2010, updated 2019) for reduction of excess abdominal fat in HIV-infected patients with lipodystrophy. It is the only GHRH analog with FDA approval for any therapeutic indication.
Tesamorelin is approved by Health Canada and is under regulatory review in other jurisdictions. It is a prescription medication requiring physician supervision and is indicated only for HIV-associated lipodystrophy in its approved labeling.
WADA prohibits tesamorelin under category S2 (Growth Hormone Releasing Factors) of the prohibited list. The peptide is a prescription medication in the US and Canada and is not available over-the-counter.
Research Studies
Tesamorelin Reduces Visceral Fat in HIV-Infected Patients (LIPO-010)
Falutz J, Allas S, Blot K, et al.
Tesamorelin Effects on Hepatic Fat and Fibrosis in HIV
Stanley TL, Feldpausch MN, Oh J, et al.
Tesamorelin and Cognitive Function in Aging
Friedman SD, Baker LD, Borber S, et al.
Long-Term Tesamorelin Treatment in HIV-Associated Lipodystrophy
Falutz J, Potvin D, Mamputu JC, et al.
Tesamorelin for NASH: A Randomized Controlled Trial
Stanley TL, Fourman LT, Feldpausch MN, et al.
