Overview
Overview
Tesamorelin is a synthetic 44-amino-acid peptide analog of Growth Hormone-Releasing Hormone (GHRH)[1]. It stimulates endogenous growth hormone release and raises IGF-1 levels, leading to enhanced lipolysis and metabolic benefits[2]. Tesamorelin is FDA-approved for reducing visceral adipose tissue in HIV-associated lipodystrophy and is studied for metabolic disorders and aging research[3][4]. Reconstitute: Add 2.5 mL bacteriostatic water per 5 mg vial → 2.0 mg/mL concentration. Standard daily do
- Category
- Growth Hormone
- Routes
- subcutaneous
Mechanism
Tesamorelin
Mechanism of action
Mechanism of action
Tesamorelin tells your pituitary gland (the small gland in your brain that controls growth hormone) to release more growth hormone (GH) in its natural rhythm. That extra GH then drives the body to break down deep belly fat and liver fat more than other fat stores. Your pituitary has docking points called GHRH receptors. Tesamorelin locks onto these receptors and turns on the same signaling pathways (cAMP and PKA) your body uses naturally. The result is a normal-shaped pulse of GH release, not a constant flood. Once GH enters the bloodstream, the liver makes more IGF-1 (insulin-like growth factor 1). IGF-1 carries out many of GH's downstream effects on fat and tissue. Trials show IGF-1 rises while other pituitary hormones stay in their normal ranges. The GH and IGF-1 rise drives fat breakdown in visceral fat (the deep fat around your organs) more than in fat under the skin. It also reduces fat buildup in the liver. Phase III trials and NAFLD studies confirmed these effects, which is what earned tesamorelin its FDA approval. Unlike injecting growth hormone directly (which can shut off your body's own GH production), tesamorelin keeps your normal feedback loops. Your brain still controls the system. Tesamorelin only amplifies the signal your body already sends.
Key research findings
- 01
Synthetic analog of full-length human GHRH(1-44) bearing an N-terminal trans-3-hexenoyl modification that improves stability; acts as a GHRH-receptor agonist that stimulates endogenous GH and raises IGF-1 (pharmacology; human study).
- 02
The most clinically validated GHRH analog in this category: multiple randomized, placebo-controlled trials in adults living with HIV measured reductions in abdominal visceral adipose tissue (human study; e.g., Falutz et al., 2007, N Engl J Med).
- 03
Holds FDA approval (as Egrifta) for a specific indication — reduction of excess abdominal visceral adipose tissue in adults with a particular HIV-associated condition (regulatory fact; stated as background, not a treatment recommendation).
- 04
Further human research has examined liver-fat endpoints (e.g., NAFLD in the HIV setting) (human study; e.g., Stanley et al., 2014, JAMA).
- 05
Because it raises IGF-1, research monitors IGF-1 and glucose parameters; observed effects in research have included injection-site reactions and effects on glucose metabolism (human study).
Primary source: LIPO-010 (Phase III, n=412): Falutz et al. HIV lipodystrophy patients showed about 15.2% visceral fat reduction at 26 weeks versus placebo, plus favorable lipid and trunk-fat changes. CTR-1011 (Phase III, n=404): Falutz et al. Replication trial showed about 11.7% VAT reduction at 26 weeks, with increased lean mass and waist changes. Pooled Phase III analysis (n=816): Consistent VAT reductions across both trials with maintenance during continued therapy and regression toward baseline after stopping. Stanley et al. 2019 (Lancet HIV, n=61): Phase II investigator-initiated trial in HIV-NAFLD: about 32% liver-fat reduction and lower fibrosis-progression rate versus placebo at 12 months. Stanley et al. 2014 (JAMA, n=54): Phase II trial in HIV with abdominal fat: significant VAT reduction over 6 months with metabolic and hepatic-signal analyses. Fourman et al. 2020 (JCI Insight): Mechanistic follow-up: tesamorelin shifted liver transcriptomic signatures toward oxidative phosphorylation and reduced inflammatory signaling. Fourman et al. 2021 (Scientific Reports): Proteomic profiles identified response pathways tied to inflammation and tissue-remodeling modulation in HIV-NAFLD. Grinspoon et al. 2011 (Phase I, n=13): Healthy men: increased overnight GH output and pulse-area effects with reversal after withdrawal. Falutz et al. 2024 (AIDS): Efficacy and safety review of tesamorelin in people with HIV on integrase inhibitors — confirms continued relevance in modern HIV care. Limitations: Direct trial evidence is in HIV-associated populations. Off-label use in non-HIV populations relies on extrapolation, not large RCTs.
Pharmacokinetic profile
Single-dose plasma curve over 24h. Shaded band = commonly-cited therapeutic window. Illustrative only.
Researched Effects
Researched benefits
Areas of active research and investigation. Results may vary and are based on preclinical or early clinical data.
Potential Benefits:
Significant reduction in visceral adipose tissue (measurable after 3–6 months)[3].
Improved lipid profiles and potential liver fat reduction in NAFLD[4].
Enhanced cognitive function in older adults (research ongoing)[4].
Well-tolerated with maintained benefits during continuous use up to 52 weeks[3].
Protocol Reference
Protocol reference
Commonly cited research range: 1–2 mg, daily.
Reference figures reported in the research literature — not a dosing recommendation. For interactive vial math and scheduling, see the Calculator and Schedule tabs.
Cited protocol & reconstitution guide
Source-backed reference fields by phase, including any volume fields authored in the cited guide.
Day 1 onward
2 mg
Weeks 1–26
2 mg
Continued therapy
2 mg
| Phase | Reference amount | Units / volume |
|---|---|---|
| Day 1 onward | 2 mg | 40 units (0.40 mL) |
| Weeks 1–26 | 2 mg | 40 units (0.40 mL) |
| Continued therapy | 2 mg | 40 units (0.40 mL) |
Titration protocol
- Day 1 onwardStart2 mg daily
No titration — full dose from day one. Subcutaneous injection in the abdomen only. Rotate sites daily. May be given at any time of day.
- Weeks 1–26Build2 mg daily
Hold the same daily dose for the full 26-week standard cycle. Keep rotating abdominal sites.
- Continued therapyMaintenance2 mg daily
Extended cycle runs 52 weeks at the same daily dose. If a dose is missed, skip it and resume on the next scheduled day — do not double up.
Storage & Handling
Storage requirements(typical for most peptides)
Can be stored for extended periods. Protect from moisture.
Store in refrigerator door. Never freeze after reconstitution.
Label vials with reconstitution date. Discard if cloudy.
Reconstitution steps
- 01🌡️Clean the workspace — Swab the vial stopper with alcohol. Let it air dry for about 10 seconds.
- 02🧴Draw 1 mL bacteriostatic water into a sterile syringe — this 5 mg vial yields 5 mg/mL.
- 03💉Add water against the wall — Push the needle through the stopper. Inject the water slowly down the side of the vial, not directly onto the powder.
- 04💧Let it flow — Allow the water to wash gently over the powder. No pressure spray.
- 05🔄Roll, do not shake — Gently roll the vial between your hands for 30 to 60 seconds until fully dissolved.
- 06🏷️Inspect the solution — Use only if the liquid is clear and colorless. Discard if cloudy or if you see particles.
- 07❄️Important: This guide is for educational purposes only and is not medical advice. For research use only. Not for human consumption.
Additional storage notes
Store at 2–8 °C (35.6–46.4 °F); newer formulations (Egrifta SV) stable at 20–25 °C (68–77 °F) before reconstitution [1] .
Reconstituted (with bacteriostatic water): Refrigerate at 2–8 °C (35.6–46.4 °F); use within 7 days [1] .
Use immediately; discard any unused portion [1] .
Do not freeze reconstituted solution; avoid repeated freeze-thaw cycles.
Clinical Evidence
Clinical evidence
FDA-approved for reducing excess abdominal fat in HIV patients. Studies show 15-20% reduction in visceral adipose tissue.
LIPO-010 (Phase III, n=412): Falutz et al. HIV lipodystrophy patients showed about 15.2% visceral fat reduction at 26 weeks versus placebo, plus favorable lipid and trunk-fat changes. CTR-1011 (Phase III, n=404): Falutz et al. Replication trial showed about 11.7% VAT reduction at 26 weeks, with increased lean mass and waist changes. Pooled Phase III analysis (n=816): Consistent VAT reductions across both trials with maintenance during continued therapy and regression toward baseline after stopping. Stanley et al. 2019 (Lancet HIV, n=61): Phase II investigator-initiated trial in HIV-NAFLD: about 32% liver-fat reduction and lower fibrosis-progression rate versus placebo at 12 months. Stanley et al. 2014 (JAMA, n=54): Phase II trial in HIV with abdominal fat: significant VAT reduction over 6 months with metabolic and hepatic-signal analyses. Fourman et al. 2020 (JCI Insight): Mechanistic follow-up: tesamorelin shifted liver transcriptomic signatures toward oxidative phosphorylation and reduced inflammatory signaling. Fourman et al. 2021 (Scientific Reports): Proteomic profiles identified response pathways tied to inflammation and tissue-remodeling modulation in HIV-NAFLD. Grinspoon et al. 2011 (Phase I, n=13): Healthy men: increased overnight GH output and pulse-area effects with reversal after withdrawal. Falutz et al. 2024 (AIDS): Efficacy and safety review of tesamorelin in people with HIV on integrase inhibitors — confirms continued relevance in modern HIV care. Limitations: Direct trial evidence is in HIV-associated populations. Off-label use in non-HIV populations relies on extrapolation, not large RCTs.
- 01Synthetic analog of full-length human GHRH(1-44) bearing an N-terminal trans-3-hexenoyl modification that improves stability; acts as a GHRH-receptor agonist that stimulates endogenous GH and raises IGF-1 (pharmacology; human study).
- 02The most clinically validated GHRH analog in this category: multiple randomized, placebo-controlled trials in adults living with HIV measured reductions in abdominal visceral adipose tissue (human study; e.g., Falutz et al., 2007, N Engl J Med).
- 03Holds FDA approval (as Egrifta) for a specific indication — reduction of excess abdominal visceral adipose tissue in adults with a particular HIV-associated condition (regulatory fact; stated as background, not a treatment recommendation).
- 04Further human research has examined liver-fat endpoints (e.g., NAFLD in the HIV setting) (human study; e.g., Stanley et al., 2014, JAMA).
- 05Because it raises IGF-1, research monitors IGF-1 and glucose parameters; observed effects in research have included injection-site reactions and effects on glucose metabolism (human study).
Evidence maturity varies by compound; much peptide research is preclinical (in vitro or animal-model). Where human data are limited, findings should be read as research observations, not clinical conclusions.
References
Literature references
Published research articles and sources related to Tesamorelin.
- 01Falutz J, et al. Effects of tesamorelin (TH9507), a growth hormone-releasing factor analog, in HIV-infected patients with excess abdominal fat: pooled analysis of two multicenter Phase 3 trials with safety extension data. Journal of Clinical Endocrinology & Metabolism (2010)et al. (2010)
- 02Stanley TL, Fourman LT, Feldpausch MN, et al. Effects of tesamorelin on non-alcoholic fatty liver disease in HIV: a randomised, double-blind, multicentre trial. Lancet HIV (2019)et al. (2019)
- 03Fourman LT, Stanley TL, et al. Effects of tesamorelin on hepatic transcriptomic signatures in HIV-associated NAFLD. JCI Insight (2020)et al. (2020)
- 04Fourman LT, Stanley TL, et al. Delineating tesamorelin response pathways in HIV-associated NAFLD using a targeted proteomic and transcriptomic approach. Scientific Reports (2021)et al. (2021)
- 05Grinspoon S, et al. Effects of a Growth Hormone-Releasing Hormone Analog on Endogenous GH Pulsatility and Insulin Sensitivity in Healthy Men. Journal of Clinical Endocrinology & Metabolism (2011)et al. (2011)
- 06Ishida J, et al. Growth hormone secretagogues: history, mechanism of action, and clinical development. JCSM Rapid Communications (2020)et al. (2020)
- 07U.S. Food and Drug Administration Egrifta SV (tesamorelin) prescribing information. FDA (2024)et al. (2024)
- 08U.S. Food and Drug Administration Egrifta WR (tesamorelin) prescribing information. FDA (2025)et al. (2025)
- 09Drugs.com Tesamorelin Monograph for Professionals. Drugs.com (2025)et al. (2025)
- 10National Institutes of Health LiverTox: Tesamorelin. NCBI Bookshelf (2023)et al. (2023)
- 11ClinicalTrials.gov Tesamorelin Effects on Liver Fat and Histology in HIV (NCT02196831). ClinicalTrials.gov (2024)et al. (2024)
- 12Falutz J, McLaughlin T, et al. Efficacy and safety of tesamorelin in people with HIV on integrase inhibitors. AIDS (2024)et al. (2024)
Observed Effects
Observed effects in cited research
Most Common Observed Effects
- Injection-site reactions are the most common. These include redness, itching, pain, swelling, and rash. In CTR-1011, injection-site issues happened in 50.7% of tesamorelin users versus 21.4% on placebo. In LIPO-010, the numbers were 30.0% versus 24.1%.
- Fluid retention, joint pain, and muscle aches can also happen because of GH-related fluid shifts. Swelling occurred in about 9.9% of tesamorelin users versus 5.8% on placebo. Muscle aches occurred in 3.7-7.7% versus 1.6-2.2% on placebo. Most cases were mild to moderate.
Blood Sugar Changes
- Trials showed more tesamorelin users had elevated HbA1c (a 3-month average blood sugar marker) compared to placebo. The FDA label recommends checking blood sugar before starting and at intervals during use.
Antibody Development
- About half of trial participants developed anti-tesamorelin IgG antibodies after 26 to 52 weeks. The good news: visceral fat reduction and IGF-1 effects were similar in people who developed antibodies and those who did not.
IGF-1 Levels
- IGF-1 is expected to rise on tesamorelin. Persistent very high levels (for example, sustained above 3 SDS in clinical context) may need clinician review, dose adjustment, or stopping.
Research Considerations
Research considerations
Prescription medication. Monitor for glucose changes. Consult healthcare provider.
- Tesamorelin (Egrifta) is FDA-approved for adults with HIV-associated lipodystrophy — meaning people on HIV medication who have built up excess belly fat. Use for any other reason is off-label and should involve a licensed clinician.
- The FDA label lists several groups who should not use tesamorelin. These include people with active cancer (any type), people who are pregnant or planning pregnancy, anyone with a known allergy to tesamorelin or mannitol (an inactive ingredient), and people with major problems of the hypothalamus or pituitary gland (the brain area that controls hormone release).
- Some groups should be reviewed carefully with a clinician before starting. These include people with type 2 diabetes or higher blood sugar, people with a history of cancer, and people with eye conditions like diabetic retinopathy. The label recommends checking blood sugar before starting and during use because GH can affect glucose levels.
- Tesamorelin is not safe in pregnancy. It can also cross into breast milk. The label recommends stopping tesamorelin if pregnancy is suspected.
Factors noted in the research literature; not patient-specific medical advice.
Regulatory Status
Regulatory status
RUO
Comparisons
Comparisons
| Compound | Mechanism | Route | Status |
|---|---|---|---|
| Tesamorelinthis | Binds to GHRH receptors to stimulate endogenous GH production. Preferentially reduces abdominal fat accumulation. | subcutaneous | Investigational / RUO |
| CJC-1295 | Binds to GHRH receptors to stimulate GH release. Modified structure provides extended duration of action (up to 7 days). | subcutaneous | Investigational / RUO |
| CJC-1295 DAC | A synthetic GHRH analog with a drug-affinity-complex (DAC) modification that binds serum albumin, greatly extending half-life and producing sustained stimulation of pituitary GH release. | subcutaneous | Investigational / RUO |
| CJC-1295 NO DAC | A synthetic 29-amino-acid GHRH analog (Modified GRF 1-29) that stimulates natural, pulsatile growth hormone secretion from the pituitary; without a DAC it has a short duration of action. | subcutaneous | Investigational / RUO |
| GHRP-2 | A synthetic hexapeptide that activates the ghrelin/GHS receptor (GHS-R1a) to stimulate dose-dependent growth hormone release; it also mildly engages prolactin and cortisol pathways. | subcutaneous | Investigational / RUO |
| Testagen | A synthetic tetrapeptide bioregulator (Lys-Glu-Asp-Gly) studied for modulation of endocrine function, particularly pituitary-gonadal regulatory pathways. | subcutaneous | Investigational / RUO |
| Thymosin Alpha-1 | A 28-amino-acid thymic peptide that modulates immune function, studied for enhancement of T-cell maturation, dendritic-cell function, and Toll-like-receptor signaling. | subcutaneous | Investigational / RUO |
Attributes shown for research comparison only; not a statement of efficacy or therapeutic equivalence.
FAQ
Frequently asked questions
Tesamorelin starts at full dose from day one — no ramp-up. The dose depends on the formulation: 1.4 mg daily for Egrifta SV, 1.28 mg daily for Egrifta WR, or 2 mg daily for research vials (matching the original Phase III trial dose). Inject under the skin of the abdomen, rotating sites each day.
Tesamorelin's half-life is about 26 to 38 minutes. That means the compound itself clears from the bloodstream quickly. The growth hormone and IGF-1 it triggers continue working in the body well beyond that window, which is why once-daily dosing is effective despite the short half-life.
Yes. Tesamorelin (brand name Egrifta) was FDA-approved in November 2010 for reduction of excess abdominal fat in HIV-infected adults with lipodystrophy. It is the only FDA-approved GHRH analogue. Use for any other purpose is off-label.
The most common observed effects are injection-site reactions (redness, itching, swelling), fluid retention with swelling in hands or feet, joint pain, and muscle aches. Some people see changes in blood sugar levels, so periodic monitoring is recommended. About half of trial participants developed antibodies to tesamorelin, but this did not reduce the drug's fat-reduction effects.
For research vials, add bacteriostatic water slowly down the inside wall of the vial (typically 2.0 mL for a 10 mg vial). Roll gently to dissolve. Do not shake. Refrigerate at 2-8C. For exact volumes by vial size, see the reconstitution table above or use the Peptide Reconstitution Calculator .
Common setups: 0.5 to 1.0 mL for a 2 mg vial, 1.0 to 2.5 mL for a 5 mg vial, and 2.0 to 5.0 mL for a 10 mg vial. Less water means a stronger mix and smaller injections. More water means a weaker mix and easier-to-measure injections. Use the reconstitution calculator for exact unit math.
Phase III trials showed visceral fat reduction of about 12-20% over 26 weeks of daily 2 mg dosing. A 12-month NAFLD trial reported about 32% liver-fat reduction versus placebo. When trial participants stopped tesamorelin, belly fat trended back toward pre-treatment levels, which suggests continued use is needed to keep results. Personal results vary and are not guaranteed.
All three target the GHRH receptor. Tesamorelin is the only one with current FDA approval and Phase III trial data showing visceral fat reduction. Sermorelin has the longest history of clinical use but is no longer made as a prescription product. CJC-1295 (with DAC) lasts longer (weekly dosing) but has no comparable trial evidence. See the Sermorelin protocol and CJC-1295 DAC protocol for compound-specific guides.
FDA-approved products are Egrifta SV (2 mg vial) and Egrifta WR (11.6 mg vial). Research-grade vials commonly come in 2 mg, 5 mg, and 10 mg sizes. The legacy 1 mg Egrifta vial is discontinued.
At 2 mg per day, a 10 mg vial gives about 5 daily doses. Reconstitute with 2.0 mL of bacteriostatic water for a 5,000 mcg/mL solution. Each daily dose is 0.40 mL (40 units on a U-100 insulin syringe). Round up your vial count to allow for priming losses.
Tesamorelin can be injected at any time of day. The original Phase III trials did not require bedtime dosing. Some users prefer morning to align with daytime activity; others prefer bedtime to match the body's natural overnight GH pulse. Consistency matters more than timing.
Storage depends on the formulation. Egrifta SV is single-use and should be injected right after mixing per the label. Egrifta WR and research-grade reconstituted vials are stored refrigerated at 35.6 to 46.4F (2-8C) for up to 28 days. Do not freeze reconstituted solution. Discard if cloudy or discolored.
No. Tesamorelin is not a scheduled controlled substance under the U.S. Controlled Substances Act. It is a prescription drug for its FDA-approved use in HIV lipodystrophy. It is, however, a prohibited substance under WADA anti-doping rules (class S2 peptide hormone).
Tesamorelin has two Phase III lipodystrophy trials (LIPO-010 and CTR-1011), pooled analyses across 816 participants, the Stanley 2019 Lancet HIV NAFLD trial, the Stanley 2014 JAMA abdominal-fat trial, and mechanistic transcriptomic and proteomic follow-up papers. An ongoing registered study (ClinicalTrials.gov NCT02196831) continues to evaluate these outcomes.
No. The FDA label and Phase III trials both start patients at the full dose on day one. Tesamorelin does not need the slow ramp-up that many other peptides use. This is one of the things that makes it different from community-derived peptide protocols.
Use the PepPal calculator for exact dose-to-unit conversions across any vial size and BAC water volume.
Research-use notice
Research Use Only. This educational content and calculation support is intended for private research documentation. It does not provide medical advice, human-use directions, or claims of safety or effectiveness.