GHRH analogue comes up often in conversation and rarely with the context attached. Here we lay out the basics in order, then work through the practical considerations.
Updated 2025-10-03. Numbers and descriptions here follow the published literature rather than marketing material.
Tesamorelin is a synthetic peptide that belongs to the growth hormone-releasing hormone (GHRH) family. Its sequence corresponds to the fully active 44-amino-acid form of human GHRH, with a single structural modification: the addition of a trans-3-hexenoyl group at the N-terminus. That modification is not found in the naturally occurring hormone and was introduced deliberately during development to improve stability against enzymatic degradation. The compound is therefore best described as a stabilized analogue rather than a naturally occurring peptide.
The native hormone is produced in the hypothalamus and acts on the anterior pituitary. Binding of GHRH to its receptor stimulates synthesis and release of growth hormone into circulation. Because the analogue retains the receptor-binding region of the parent sequence, it engages the same receptor and triggers the same downstream signaling. The result is increased growth hormone secretion from pituitary cells, which in turn influences hepatic production of insulin-like growth factor 1. This axis is the basis for the compound's measured biological effects.
Tesamorelin is a synthetic peptide that belongs to the growth hormone-releasing hormone family and contains the same forty-four amino acid sequence as endogenous GHRH, extended at the amino terminus by a trans-3-hexenoyl group. That small fatty acid modification protects the peptide from rapid cleavage by dipeptidyl peptidase-4, the enzyme that shortens the half-life of native GHRH to only a few minutes. Chemically the compound is produced by solid-phase peptide synthesis, purified by chromatography, and supplied as a sterile lyophilized powder for reconstitution.
Regulatory approval in the United States came in 2010, when the Food and Drug Administration cleared the peptide for the reduction of excess abdominal fat in adults with HIV infection and associated lipodystrophy. The decision rested mainly on two randomized phase 3 trials that enrolled roughly eight hundred patients and ran for twenty-six weeks. Participants receiving active drug showed substantially greater declines in visceral adipose tissue than those receiving placebo, while total body weight changed comparatively little. A reformulated presentation was later approved, and the product has remained a niche therapy rather than a general weight-loss agent.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C221H366N72O67S | Reflects a 44-residue peptide with one N-terminal modification |
| Approximate molecular weight | 5136 Da | Sequence length and single acyl group determine the mass |
| Appearance | White to off-white lyophilized powder | Typical form of a purified synthetic peptide |
| Solubility class | Soluble in water and aqueous buffer | Peptide backbone favors aqueous dissolution |
| Common synonyms | GHRH(1-44) analogue; Egrifta | Descriptive name and approved brand name |
Tesamorelin is a synthetic peptide of forty-four amino acids whose sequence reproduces human growth hormone-releasing hormone. Its distinguishing feature sits at the amino terminus, where a trans-3-hexenoyl group replaces the free amine. That acylation slows cleavage by dipeptidyl peptidase IV, an enzyme that otherwise removes the first two residues and inactivates the natural hormone quickly. The modified peptide therefore persists longer in circulation while keeping the same receptor target. It is handled as a lyophilized solid and dissolved shortly before use.
Signaling begins at the GHRH receptor, a class B G protein-coupled receptor displayed on somatotroph cells of the anterior pituitary. Receptor occupancy activates Gs proteins, which raise adenylyl cyclase activity and intracellular cyclic AMP, in turn driving protein kinase A dependent pathways. The downstream output is synthesis and pulsatile secretion of growth hormone into the bloodstream. Hepatic tissue and peripheral sites respond by increasing insulin-like growth factor 1 production. Somatostatin and IGF-1 itself supply negative feedback that caps the size and duration of each secretory burst.
UNC Rex Hospital is a general hospital located in Raleigh, North Carolina. It is the capital city's oldest hospital, founded by a bequest from John T. Rex (1771–1839), a local tanner, planter, and owner of enslaved families, and named in his honor. Originally located on what is now Dorothea Dix campus, and later on St. Mary's Street, Rex is now located in west Raleigh at the corner of Blue Ridge Road and Lake Boone Trail. Rex Health Care's services include oncology, heart and vascular, surgical services (including bariatric, heartburn, GI, orthopedic, neuro, and spinal), rehabilitation, emergency department, urgent care, women's services, and wound healing. Rex is a member of the UNC Health Care system, a non-profit integrated health care system, owned by the state of North Carolina and based in Chapel Hill, North Carolina. Rex is located just 2 miles from the Lenovo Center, and is the official healthcare provider of the Carolina Hurricanes and NC State Wolfpack.
=== Heart attacks after use of Vioxx === In 1999, the U.S. Food and Drug Administration (FDA) approved Vioxx (known generically as rofecoxib), a Merck product for treating arthritis. Vioxx was designed as a selective inhibitor of the enzyme cyclooxygenase-2. Such compounds were expected to cause less gastrointestinal bleeding than older anti-inflammatory drugs such as naproxen, which were associated with 20,000 hospitalizations and 2000 deaths each year. Vioxx became one of the most prescribed drugs in history. Thereafter, studies by Merck and by others found an increased risk of heart attack associated with Vioxx use when compared with naproxen. Merck adjusted the labeling of Vioxx to reflect possible cardiovascular risks in 2002. On September 23, 2004, Merck received information about results from a clinical trial it was conducting that included findings of increased risk of heart attacks among Vioxx users who had been using the medication for over eighteen months. On September 28, 2004, Merck notified the FDA that it was voluntarily withdrawing Vioxx from the market, and it publicly announced the withdrawal on September 30. An analysis for the period 1999–2004, based on U.S. Medical Expenditure Survey data, reported that Vioxx was associated with 46,783 heart attacks in the US, and along with the other popular COX-2 inhibitor Celebrex, an estimated 26,603 deaths from both. About 50,000 people sued Merck, claiming they or their family members had suffered medical problems such as heart attacks or strokes after taking Vioxx.
=== Medications === Prolactin secretion in the pituitary lactotroph cells is normally suppressed by the brain chemical dopamine, which binds to dopamine receptors. Drugs that block the effects of dopamine at the pituitary or deplete dopamine stores in the brain may cause the pituitary to secrete excess prolactin without an inhibitory effect. These drugs include the typical antipsychotics: phenothiazines such as chlorpromazine, and butyrophenones such as haloperidol; atypical antipsychotics such as risperidone and paliperidone; gastroprokinetic drugs used to treat gastro-esophageal reflux and medication-induced nausea (such as that from chemotherapy): metoclopramide and domperidone; less often, alpha-methyldopa and reserpine, used to control hypertension; and TRH. Aripiprazole, while an atypical antipsychotic, lowers prolactin levels as it is contains both agonistic and antagonistic dopamine-receptor activity. It is well known that estrogen stimulates prolactin secretion by upregulating the formation of lactotrophs. However, there is mixed evidence on whether estrogen-containing oral contraceptives significantly increase prolactin levels. Gender-affirming therapy for transgender women that includes estrogen and antiandrogens has been shown to increase prolactin levels, but it is unclear whether the cause is due to the estrogen or antiandrogen therapy. The melatonin receptor agonist ramelteon also increases the risk of hyperprolactinemia, however, the mechanism is unclear.
Sources: en.wikipedia.org
=== Duchenne muscular dystrophy === Several morpholino oligos have been approved to treat specific groups of mutations causing Duchenne muscular dystrophy. In September 2016, eteplirsen (ExonDys51) received FDA approval for the treatment of cases that can benefit from skipping exon 51 of the dystrophin transcript. In December 2019, golodirsen (Vyondys 53) received FDA approval for the treatment of cases that can benefit from skipping exon 53 of the dystrophin transcript. In August 2020, viltolarsen (Viltepso) received FDA approval for the treatment of cases that can benefit from skipping exon 53 of the dystrophin transcript.
=== Structure === Muscimol was first isolated from Amanita pantherina by Onda in 1964, and thought to be an amino acid or peptide. Structure was then elucidated by Takemoto, Eugster, and Bowden. Muscimol is a semi-rigid isoxazole containing both alcohol and aminomethyl substituents. Muscimol is commonly portrayed as a tautomer, where it adopts an amide-like configuration. It is also commonly shown as a zwitterion.
=== 25 March === Ukrainian commander-in-chief Valerii Zaluzhnyi posted on Facebook that Ukrainian forces in Bakhmut had managed to "stabilize the situation". President Putin said Russia would go ahead with its plan to station tactical nuclear weapons in Belarus. He also stated that a small number of Iskander missiles able to carry them were already in Belarus. A storage facility for tactical nuclear weapons is to be finished by 1 July.
Sources: en.wikipedia.org
It shares the 44-residue sequence of human GHRH but carries an added trans-3-hexenoyl group at its N-terminus. That addition does not occur in the natural hormone and serves mainly to resist enzymatic breakdown. The receptor target and signaling pathway remain the same.
It binds the growth hormone-releasing hormone receptor on anterior pituitary cells. Activation of that receptor promotes synthesis and release of growth hormone. The effect propagates through the growth hormone and insulin-like growth factor 1 axis.
Native GHRH is cleared quickly by peptidases, which limits how long it can stimulate its receptor. The added group hinders one of the primary cleavage enzymes. The practical consequence is a longer period of receptor activity per dose.
It is a laboratory-made peptide of forty-four amino acids whose sequence matches human growth hormone-releasing hormone, with a modified amino terminus. The modification is a short unsaturated fatty acid chain attached to the first residue. This change slows enzymatic breakdown and lengthens the time the peptide stays active in circulation.