Tesamorelin vs Sermorelin: Evidence, Doses and Differences

The Quick Answer

Tesamorelin is a synthetic 44 amino acid growth hormone releasing factor analogue with a hexenoyl group and a molecular weight of 5135.9 Da, supplied as an acetate salt. It has been FDA approved since 2010 (BLA 022505) for one thing: reduction of excess abdominal fat in HIV associated lipodystrophy. Its label is explicit that it is not indicated for weight loss management as it has a weight neutral effect. The trials behind it run from 2008 to 2025 and are in adults.

Sermorelin is a 29 amino acid analogue of human GHRH, described in the literature as the shortest synthetic peptide with full GHRH activity. Its approved product Geref is discontinued in the United States, though FDA records note the discontinuation was not for safety or effectiveness reasons. Its human trial record is in prepubertal children, most of them growth hormone deficient and some with idiopathic short stature or growth hormone neurosecretory dysfunction, plus one small adult intravenous dose response study.

Both raise growth hormone and then IGF-1 by acting on the pituitary. That shared mechanism is the reason the two names travel together. The gap is everything around it: tesamorelin has a modern adult prescription evidence base for a narrow HIV indication, and sermorelin has an older paediatric evidence base and no current label.

Neither compound has been tested for the anti aging or body composition use in healthy adults that drives this search. The adult tesamorelin research on body composition outside HIV was in abdominally obese adults with reduced growth hormone secretion, not a healthy adult population, and the two have never been compared to each other in a trial. That is the most important line on the page, and everything below fills it in.

What Each One Actually Is

Tesamorelin is a human growth hormone releasing factor (GRF) analog produced synthetically. The FDA label describes it as the 44 amino acid sequence of human GRF plus a hexenoyl moiety, a short carbon chain attached to the tyrosine residue at the N terminal part of the molecule, prepared as an acetate salt, with a molecular weight of 5135.9 Da as free base. The literature also calls it a GHRH(1-44) analog (PMID 23015655) and a stabilized growth hormone releasing hormone analogue (PMID 28617838). The hexenoyl group is what this literature describes as stabilising the peptide. It is a peptide.

Sermorelin is a 29 amino acid analogue of human GHRH and is described as the shortest synthetic peptide with full biological activity of GHRH. By both intravenous and subcutaneous routes it specifically stimulates growth hormone secretion from the anterior pituitary (PMID 18031173). It too is a peptide, and it is the fragment, not the full length sequence.

So the core structural difference is length and stability. Tesamorelin is the full 44 residue GRF sequence with a stabilising group; sermorelin is the 29 residue fragment. Neither is growth hormone itself. Both are secretagogues that ask the pituitary to release its own growth hormone, then let IGF-1 follow, rather than supplying growth hormone directly the way somatropin does.

Approval Status and History

Tesamorelin is a currently marketed FDA drug: BLA 022505, Theratechnologies, first approved 10 November 2010, marketing status Prescription. Two products carry current FDA labeling, EGRIFTA WR and EGRIFTA SV, and the label states that the two are not substitutable because their strengths, reconstitution and storage differ. The approved indication is narrow, reduction of excess abdominal fat in HIV associated lipodystrophy, and the label adds that the drug is not indicated for weight loss management as it has a weight neutral effect. There is no European marketing authorisation: Ferrer Internacional withdrew the Egrifta application to the European Medicines Agency on 21 June 2012, late in the procedure, with unresolved issues remaining after the last round of questions.

Sermorelin is in a different place entirely. There is no current FDA labeled sermorelin product: a DailyMed query for sermorelin returned zero labels on the same call that returned two for tesamorelin, so the absence is a genuine null, not a broken search. It was formerly approved as Geref by EMD Serono: NDA 019863, approved 28 December 1990 at 0.05 mg base per ampoule, and NDA 020443, approved 26 September 1997 at 0.5 mg and 1 mg base per vial. Both applications are now listed as Discontinued.

One qualifier belongs with that word every time it appears. Every Geref strength in the FDA record carries a Federal Register determination that the product was not discontinued or withdrawn for safety or effectiveness reasons. Discontinued here is a commercial status, not a safety verdict, and this research did not establish the commercial reasons behind it.

A limit worth stating plainly: the historical Geref label text, its approved dose wording, its contraindications and its adverse reaction table, could not be read in this research. The one archived Geref document the FDA exposes is a scanned PDF with no text layer, and reading scans by OCR was out of scope. So this page never quotes a sermorelin label dose. Every sermorelin figure below is a trial or review figure tied to its PMID.

What The Trials Actually Measured

The two evidence bases barely overlap. A single clinical trial search covering both compounds returned 57 records, and the top 15 by relevance held 13 tesamorelin records and 1 GHRH(1-29) record. The tesamorelin studies run 2008 to 2025 and are in adults; the sermorelin studies date 1993 to 2000 and are almost entirely in children, with one small adult intravenous dose response study. Read each side for what it is, not as a scoreboard.

Tesamorelin, in adults

The registration programme was two multicentre randomized double blind placebo controlled studies, each a 26 week main phase plus a 26 week extension, randomizing patients 2:1 to tesamorelin 2 mg subcutaneously once daily or placebo (trial dose, not a recommendation, EGRIFTA label). Study 1 (NCT00123253) randomized 412 patients. Across the programme, 740 HIV infected patients were treated in trials, 543 of them during the initial 26 week placebo controlled phase.

In a JAMA trial of 50 HIV infected adults on 2 mg subcutaneously daily for 6 months (trial dose, not a recommendation, PMID 25038357), the visceral fat treatment effect was -42 cm2 (95% CI -71 to -14, P = .005) and the median liver fat change was -2.0 percent against +0.9 percent on placebo (P = .003). A Lancet HIV trial of 61 adults on 2 mg subcutaneously daily for 12 months then a 6 month open label phase (trial dose, not a recommendation, PMID 31611038) reported a hepatic fat fraction absolute effect of -4.1 percent (95% CI -7.6 to -0.7, p = 0.018), and 35 percent of the drug group reached a liver fat fraction under 5 percent against 4 percent on placebo. The same trial reduced liver fat and prevented fibrosis progression over 1 year (PMID 32701508).

Outside HIV, a trial in 60 abdominally obese adults with reduced growth hormone secretion used 2 mg once daily for 12 months (trial dose, not a recommendation, PMID 23015655): the visceral fat treatment effect was -35 cm2 (P = 0.003), IGF-I rose by 92 micrograms per litre (P less than 0.0001), and no changes in fasting or 2 hour glucose or glycated hemoglobin were seen. A durability analysis of 410 patients randomized then re randomized at week 26 (PMID 18690162) found the visceral fat change sustained at -18 percent over 52 weeks, but on discontinuation the visceral fat reaccumulated, and the authors concluded the effects do not last beyond the duration of treatment.

Not every endpoint moved. A phase 2 open label study randomized 73 adults 3:2 to 2 mg subcutaneously daily for 6 months to test neurocognition (trial dose, not a recommendation, PMID 39813152). Waist circumference fell (median difference -2.7 cm, P = .015) but the between group cognitive difference was not significant (P = .673), and the authors reported no clear benefit. That is a real result and it belongs here next to the positive ones.

Sermorelin, mostly in children

The use the literature ties to sermorelin's approval is diagnostic testing. A review reports intravenous sermorelin at 1 microgram per kg as a rapid and relatively specific test for the diagnosis of growth hormone deficiency (diagnostic trial dose, not a recommendation, PMID 18031173), with the stated limit that a normal response cannot exclude growth hormone deficiency due to a hypothalamic deficit.

The largest treatment cohort located is a multicentre open label study, no placebo arm, of 110 previously untreated prepubertal growth hormone deficient children, 86 evaluable, given 30 micrograms per kg per day subcutaneously at bedtime for up to 1 year (trial dose, not a recommendation, PMID 8772599). Mean height velocity rose from 4.1 cm per year at baseline to 8.0 at 6 months and 7.2 at 12 months, and 74 percent were rated good responders at 6 months. A randomized trial in 43 prepubertal children with hypothalamic growth hormone deficiency compared 30 micrograms per kg per day subcutaneously in three divided doses, 60 micrograms per kg per day subcutaneously in three divided doses, and growth hormone at 0.1 IU per kg per day over 6 months (trial doses, not a recommendation, PMID 8329826). Height velocity was lowest in the low dose group and comparable in the high dose and growth hormone groups, and an increase in height standard deviation score for bone age occurred only in the growth hormone group.

The honest comparative line comes from that same review: sermorelin and somatropin have not been compared directly at the recommended dose, but height velocity gains on subcutaneous sermorelin 30 micrograms per kg per day were less than those in children receiving once daily subcutaneous somatropin 30 micrograms per kg (trial doses, not a recommendation, PMID 18031173). The effect of long term sermorelin on final adult height is yet to be determined. On durability, a study of 24 children on 30 micrograms per kg once nightly for 6 months (trial dose, not a recommendation, PMID 10905389) found growth rates not significantly different from pre therapy rates 6 months after the treatment stopped.

The only adult sermorelin data fetched is a pharmacology probe, not a treatment course: 10 adult male volunteers received intravenous boluses of 1, 10 and 100 micrograms of GHRH(1-29) (trial doses, not a recommendation, PMID 7921207), where 10 and 100 micrograms produced significant peak growth hormone responses and 1 microgram did not. Nothing in the fetched record studies sermorelin as an adult treatment.

The Doses On Record

Here is every dose figure this page can source, each tied to the study or label it came from. None is a recommendation, none is a protocol, and the page gives no instructions for reconstitution or administration technique. A figure is only as good as the population it was measured in, so the population is attached to each one.

Side by Side Comparison

The table lines up two compounds that were never lined up in a trial. Tesamorelin carries a modern adult prescription evidence base for a narrow use; sermorelin carries an older paediatric record and no current label. The rows are facts about each on its own, not a ranking of one against the other.

Side Effects and Tolerability

Tesamorelin has a full FDA safety section because it is a currently marketed drug. The most common adverse reactions above 5 percent are, in the label wording, arthralgia, injection site erythema, injection site pruritus, pain in extremity, peripheral edema and myalgia. The label carries seven warnings: increased risk of neoplasms, elevated IGF-1, fluid retention that may include edema and carpal tunnel syndrome, glucose intolerance or diabetes mellitus, hypersensitivity reactions, injection site reactions, and increased mortality in patients with acute critical illness. It is contraindicated in disruption of the hypothalamic pituitary axis, active malignancy, known hypersensitivity, and pregnancy.

The IGF-1 signal is quantified in the label: among patients who received the drug for 26 weeks, 47 percent had IGF-1 above 2 standard deviation scores and 36 percent above 3, with the effect seen as early as 13 weeks. The label directs monitoring of IGF-1 and says to consider discontinuing at persistent elevations. In the trials, participants reported more localised injection site complaints than placebo, though none were judged serious (PMID 31611038), and the drug was generally well tolerated with a similar frequency of adverse events between groups (PMID 38905488). The glucose picture is best read in both halves: a transient fasting glucose rise at 2 weeks was no longer significant at 6 months (PMID 25038357), there was no difference in fasting glucose or glycated hemoglobin at 12 months (PMID 31611038), and no change in glycaemic control over 12 weeks in diagnosed type 2 diabetics (PMID 28617838), yet the label still carries glucose intolerance as a warning.

Sermorelin has no current FDA adverse reaction table to quote, because there is no current label. What the literature reports is milder in tone and thinner in volume: a review states that intravenous single doses and repeated once daily subcutaneous doses were well tolerated, with transient facial flushing and pain at the injection site the most commonly reported events (PMID 18031173). In the 110 child, 1 year cohort, no adverse biochemical or hormonal changes were noted, there was no change in fasting glucose, and no excessive generation of IGF-1 occurred (PMID 8772599).

One contrast is tempting and has to be drawn carefully. The paediatric sermorelin cohort at 30 micrograms per kg once daily reported no excessive IGF-1 generation (PMID 8772599), while the tesamorelin label reports 47 percent of patients above 2 standard deviation scores at 26 weeks (EGRIFTA label). Those are different populations, different doses, different eras and different assays. Each is true of its own source. Neither is a head to head safety result, and this page does not present them as one.

Vietnam Availability Reality

Neither compound appears in the active substance databases of Long Chau or Pharmacity, the two chains checked. Both target pages returned a 404 on 2026-09-06, while control substances on the same databases, somatropin and gonadorelin, returned 200 on the same date with the same client. That controlled result makes this a genuine null for those two databases, not a failed lookup or a blocked page. Because no product page exists at either chain for either compound, there is no price to record from either. The honest position is no published figure.

For contrast, the same chains do list the growth hormone itself. Long Chau carries somatropin, which it classifies in Vietnamese as a growth hormone, hormone tang truong, in injectable presentations from 0,6 mg up to 12 mg. There is no equivalent listing for tesamorelin or sermorelin at either chain.

Three things could not be checked in this research, and none of them is the same as absence. Registration status with the Drug Administration of Vietnam could not be verified, because the drug data bank did not resolve from the network used. The An Khang chain was unreachable. And no clinic availability was confirmed, because the research stopped at its source cap before any clinic page could be fetched and quoted. So the page does not say either compound is unregistered or unavailable in Vietnam. It says the two chains checked do not list them, and the rest is unchecked rather than established.

How to Read This Comparison

The Bottom Line

Tesamorelin is the one with a modern adult prescription evidence base, and that base is narrow: HIV associated lipodystrophy, weight neutral, not a weight loss drug, with effects that reaccumulate when treatment stops. The trials are real and the doses on the page are trial and label figures, not recommendations.

Sermorelin is the older, shorter GHRH fragment whose approved product is discontinued, though not for safety reasons, and whose human trial record is paediatric. Even in children, the effect of long term treatment on final adult height is yet to be determined.

No head to head trial was found in this research, and the adult use that brings most people to this comparison has no trial behind it at all. That absence is the most important fact on the page, and it is the one that most of the confident ranking online quietly skips.

None of this is medical advice. Both are compounds a licensed prescriber handles, and this page publishes the evidence, not a decision.

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