Tesamorelin FDA Approved
Egrifta — Full-Length GHRH Analog
Tesamorelin (Egrifta) is a synthetic trans-3-hexenoic acid-modified analog of full-length GHRH(1-44), FDA-approved for reducing visceral abdominal fat in HIV-infected patients with lipodystrophy. Unlike truncated GHRH analogs (Sermorelin), it retains all 44 amino acids of native GHRH for maximal pituitary receptor engagement. Also studied for cognitive enhancement in older adults and NAFLD. Evidence Grade: A.
Overview
Tesamorelin was developed by Theratechnologies (Canada) as a GHRH analog for HIV-associated lipodystrophy — a condition where antiretroviral therapy causes excess visceral fat accumulation. The modification (trans-3-hexenoic acid on the alpha-amino group) protects against DPP-4 cleavage while preserving full GHRHR binding activity.
Phase III IGLARIFY trials demonstrated 15–20% reduction in visceral adipose tissue (VAT) over 26 weeks vs placebo in HIV lipodystrophy, with improvements in triglycerides and patient-reported body image. Effects were maintained through 52 weeks of continuous treatment but reversed upon discontinuation, establishing the need for ongoing therapy.
Beyond its approved indication, tesamorelin is under investigation for NAFLD/NASH (non-alcoholic fatty liver disease) and cognitive aging. A landmark 20-week RCT showed significant improvements in verbal memory and executive function in cognitively normal older adults — a finding with substantial implications for GH axis interventions in aging.
Mechanism of Action
Tesamorelin activates GHRHR on anterior pituitary somatotrophs with the same potency as full-length native GHRH, stimulating GH synthesis and pulsatile secretion. The daily injection timing exploits the physiological GH pulse architecture — tesamorelin amplifies the early-morning pulse rather than creating sustained elevation, preserving pulsatile GH signaling patterns.
Visceral adipose tissue is particularly sensitive to GH's lipolytic effects — VAT expresses higher GH receptor density than subcutaneous fat and responds preferentially to GH-stimulated lipolysis via HSL activation. This explains why GH axis interventions (tesamorelin, GH itself) produce disproportionate visceral vs subcutaneous fat reduction.
Cognitive effects may be mediated by IGF-1 signaling in the hippocampus — IGF-1 promotes neurogenesis, synaptic plasticity, and BDNF expression. Tesamorelin's moderate IGF-1 elevation (within physiological range) may restore age-related declines in hippocampal IGF-1 signaling, explaining observed verbal memory improvements.
Research Protocol A
| Parameter | FDA Approved | Research (Off-Label) |
|---|---|---|
| Dose | 2 mg/day | 2 mg/day |
| Frequency | Once daily | Once daily |
| Route | SubQ (abdomen) | SubQ (abdomen) |
| Timing | Before bedtime | Evening fasted |
| Duration | 26+ weeks continuous | 12–26 weeks |
Notes
- Effects on visceral fat reverse upon discontinuation — long-term continuous use required to maintain benefits
- Monitor fasting glucose and HbA1c (mild insulin resistance)
- Store lyophilized vials at room temperature; mix immediately before use (diluent provided)
Side Effects & Safety
- Injection site reactions (redness, pain) — most common adverse event in trials
- Peripheral edema — GH-related fluid retention
- Arthralgia / joint pain — elevated IGF-1 effect
- Mild insulin resistance — fasting glucose +0.4 mmol/L in trials
- Nausea (uncommon, ~4%)
- No significant cardiovascular adverse events in Phase III data
Contraindications
- Active malignancy or history of pituitary tumors
- Pregnancy (animal data suggest risk)
- Acromegaly or elevated baseline IGF-1
- Uncontrolled diabetes (insulin resistance risk)
Clinical Evidence
N=412. Phase III RCT. Tesamorelin 2 mg/day reduced visceral fat by 15.2% vs +5% for placebo at 26 weeks. Significant improvements in triglycerides and patient satisfaction. Led to FDA approval (Egrifta).
20-week RCT, N=152 cognitively normal older adults. Tesamorelin 2 mg/day significantly improved verbal memory (Rey Auditory Verbal Learning Test) and executive function vs placebo, with effect sizes comparable to early cognitive interventions.
Documented tesamorelin 2 mg/day reduced liver fat content by ~35% vs placebo over 6 months in HIV-infected adults with NAFLD, providing evidence for hepatic application beyond visceral fat.
Stacking Recommendations
| Stack Partner | Synergy |
|---|---|
| Ipamorelin | GHRH priming (Tesamorelin) + GHSR trigger (Ipamorelin) for enhanced GH pulse |
| AOD-9604 | GHRH-driven GH pulse + targeted beta-3 AR lipolysis |
| Semaglutide | GLP-1 appetite suppression + GHRH-mediated visceral fat reduction |
Frequently Asked Questions
Explore More
Truncated GHRH analog
Selective GHRP stack partner
GHRH analog with DAC option
GH fragment fat metabolism
Browse all 251 compounds
Build GH protocols
