Best Tesamorelin Research Suppliers 2026: COAs & Identity

The best Tesamorelin suppliers for research are the ones whose paperwork proves which molecule is in the vial. That means a certificate of analysis (COA) for the current lot, from a named laboratory, showing HPLC purity and a separate mass-spectrometry identity result that matches the 44-residue peptide and its N-terminal hexenoyl group. A purity percentage on its own proves none of that.

This guide covers analytical documentation and sourcing for laboratory research only. It does not discuss, and nothing here supports, any human or animal use.

How to Choose the Best Tesamorelin Suppliers for Research

A useful supplier is one whose claims you can check yourself. Peptides Exchange sells Tesamorelin, so read this as a supplier’s guide rather than an independent review; we don’t rank competitors, and every criterion below applies to us too. The Federal Trade Commission’s rule on consumer reviews bars businesses from presenting company-controlled review content as independent (Federal Register), which is one more reason we publish criteria instead of a leaderboard.

Criterion	What to look for	Why it matters
Exact compound	“Tesamorelin” named, not just “GHRH analog”	Several different peptides share that family label
Sequence and modification	The 44 residues listed, plus the trans-3-hexenoyl group on Tyr1	This is what separates Tesamorelin from native GHRH(1-44)
Salt form	Free base or acetate stated, with matching CAS and formula	Form changes CAS, formula weight, and how content is reported
Lot match	COA lot number matches the vial label	A “representative” COA describes someone else’s material
Purity	HPLC result with the chromatogram shown	A bare percentage can’t be evaluated
Identity	LC-MS or MS with observed vs. expected mass	Purity doesn’t show the main peak is the right molecule
Named lab	Lab name, report number, test date, and a way to verify	Unverifiable reports carry little weight
Compliant marketing	No dosing, outcome, or injection-supply language	FDA treats those as evidence of intended human use

New to research materials in general? Start with What Are Research Peptides?

What Tesamorelin Is, Chemically

Tesamorelin is a synthetic 44-amino-acid analog of human growth hormone-releasing hormone, GHRH(1-44), with a trans-3-hexenoyl group attached to the N-terminal tyrosine. Its development code was TH9507. For background on the compound itself, see What Is Tesamorelin?

Identifier	Value	Source
Sequence (44 AA)	YADAIFTNSY RKVLGQLSAR KLLQDIMSRQ QGESNQERGA RARL	PubChem CID 16137828
N-terminal modification	(3E)-hex-3-enoyl on Tyr1	PubChem
CAS (free peptide)	218949-48-5	PubChem
CAS (acetate salt)	901758-09-6	Confirm against the supplier’s COA
Molecular formula (free peptide)	C221H366N72O67S	PubChem
Average molecular weight	about 5136 g/mol	PubChem

The sequence is written in groups of ten so it can be checked residue by residue against a supplier’s listing. If you need a refresher on how residues and peptide bonds build a chain like this, see What Are Peptides?

Why the N-Terminal Group Is the Key Identity Check

The hexenoyl group is the feature that makes the molecule Tesamorelin. Without it, the same 44 residues are unmodified human GHRH(1-44). A label reading “GHRH analog, 44 amino acids” therefore doesn’t tell you which of the two you have.

Mass spectrometry can tell them apart, because the hexenoyl group adds measurable mass. An identity result should report an observed mass consistent with the modified peptide, not just “conforms.”

Length is the other quick check. Sermorelin is a 29-residue fragment of GHRH, so a “Tesamorelin” COA showing a mass near 3.4 kDa would point to the wrong material entirely (What Is Sermorelin?). CJC-1295 is a different modified GHRH analog again (What Is CJC-1295 + Ipamorelin?).

Free Base vs. Acetate: Reading the Form on a COA

Tesamorelin can be supplied as the free peptide or as an acetate salt. The acetate carries counterions, so its CAS number, formula, and formula weight differ from the free peptide.

The practical question is simple: which form did the lab test, and is content reported as peptide or as salt? A product page that lists both CAS numbers next to a single free-base weight leaves that open. The COA should close it.

What a Tesamorelin COA Should Show

Our field-by-field walkthrough is in Peptide Certificate of Analysis: How to Read a COA. For Tesamorelin specifically, a complete COA includes:

Compound name as “Tesamorelin,” with the form (free peptide or acetate)
Lot number that matches the vial, plus received and reported dates
HPLC purity with the chromatogram, not a percentage alone
Identity by LC-MS or MS, showing observed mass next to expected mass
Net content per vial, with the method used to measure it
Laboratory name, report or accession number, and a way to verify the report with the lab
Endotoxin result where the lab ran one, with method and units

Why HPLC Alone Can’t Verify Tesamorelin

HPLC measures purity: the share of detected material sitting in the main peak. It does not identify what the main peak is. A sample of unmodified GHRH(1-44), or a truncated sequence, could still show a tall main peak.

Mass spectrometry answers the identity question. For a peptide of about 5.1 kDa, electrospray instruments usually see several multiply charged ions, which software combines into one molecular mass. That deconvoluted mass is what should match Tesamorelin. Our HPLC vs. LC-MS guide explains how the two methods work together.

Regulators take the same view of synthetic peptides. FDA’s guidance on highly purified synthetic peptides treats identity confirmation and the peptide-related impurity profile as separate questions, because impurities such as deletion or modified sequences can matter even when purity looks high (FDA guidance). That guidance is written for drug applications, not research reagents, but the analytical logic carries over.

Net Content, Endotoxin, and Lab Credentials

Net content is how much peptide the lab measured in the vial. It’s a different number from purity: a vial can be high-purity and under-filled, or the reverse. Ask how the lab quantified it and whether the figure is peptide or salt.

Endotoxin results matter for some in-vitro work, because bacterial endotoxin can interfere with cell-based assays. The standard method is the limulus amebocyte lysate (LAL) test in USP <85>, which FDA recognizes as interchangeable with the European and Japanese pharmacopoeia chapters (FDA Q4B Annex 14; FDA on endotoxin testing). An endotoxin result is an analytical measurement, not a statement that material is suitable for any use in people or animals.

Lab credentials such as ISO/IEC 17025 accreditation show a lab was assessed for specific methods (Microbac). Check that the method on your COA falls inside that scope.

Tesamorelin’s Regulatory Status, and Why It Matters to Researchers

Tesamorelin is not an unapproved orphan compound. It is the active ingredient in FDA-licensed prescription products, the EGRIFTA line (DailyMed; FDA label). Because it is a polypeptide of more than 40 amino acids, its approval moved from a drug application to a biologics license on March 23, 2020 (FDA).

Research-grade Tesamorelin is not that product. It is not made or released under the licensed product’s controls, and a research supplier can’t borrow the approval to describe its material.

FDA has also made clear that a “research use only” label doesn’t decide how a product is regulated. Under 21 CFR 201.128, intended use is judged from the seller’s objective intent, including labeling, advertising, and statements. On August 24, 2026, FDA issued warning letters to online sellers whose Tesamorelin listings carried research disclaimers (NuScience Peptides; Royal Peptides). In the NuScience letter, FDA cited clinical-outcome statements on the product pages, bacteriostatic water sold for reconstitution, and a “peptide calculator.” Earlier letters followed the same reasoning (Summit Research Peptides; Arent Fox Schiff; Sheppard Mullin).

For a researcher, this is a sourcing signal. A supplier marketing Tesamorelin with outcome claims is both out of step with the law and less likely to be a stable, documented source.

Red Flags When Comparing Tesamorelin Research Suppliers

Documentation red flags

“GHRH peptide” or “growth hormone peptide” with no compound name or sequence
No mention of the N-terminal modification anywhere in the listing or COA
CAS, formula, or weight that don’t match the stated form
HPLC purity with no identity result, or “identity: conforms” with no mass shown
No lot number, an old COA, or one COA reused across batches
An unnamed lab, or a report the lab can’t confirm

Marketing red flags

Body-composition, metabolic, or other outcome claims on a research listing
Dosing charts, “protocols,” reconstitution calculators, or injection supplies sold alongside
Suggestions that research material is the same as, or equivalent to, the approved prescription product

A flag means evidence is missing, not that a supplier is guilty of anything. Ask for the missing record before deciding. You can also search any supplier’s name in FDA’s public warning letter database.

How Peptides Exchange Documents Tesamorelin

We apply the same checklist to our Tesamorelin listing. Here is where it stands today, including the gaps.

Criterion	Peptides Exchange Tesamorelin
Sizes	10 mg and 20 mg vials
Testing laboratory	Freedom Diagnostics, an outside lab (COAs page)
Methods	HPLC-UV for purity, LC-MS for identity
Current published COA	20 mg vial: 99.79% HPLC purity, 26.63 mg measured net content (view COA)
Lot number on COA	[CONFIRM: lot number and that it matches current vials]
Observed mass shown	[CONFIRM: does the COA print the observed mass?]
Sequence and modification on listing	Not yet shown on the product page; [ADD to listing]
CAS, formula, salt form on listing	Not yet shown on the product page; [ADD to listing]
Endotoxin	[CONFIRM: tested or not; if yes, method and units]
Research-use terms	Stated on every page; no dosing, outcome, or use guidance

The measured net content on the 20 mg report is above nominal. If a precise amount matters for your protocol, weigh or quantify on receipt rather than relying on the label figure. Questions about any result go to support@peptidesexchange.com, and the same request is worth making to any supplier.

A 10-Point Checklist for Any Tesamorelin Supplier

The listing names Tesamorelin, not a generic GHRH analog.
The 44-residue sequence is shown and matches YADAIFTNSY RKVLGQLSAR KLLQDIMSRQ QGESNQERGA RARL.
The trans-3-hexenoyl group on Tyr1 is identified.
The form (free peptide or acetate) is stated, with matching CAS and formula.
A COA exists for the current lot, and the lot number matches the vial.
HPLC purity is shown with the chromatogram.
LC-MS or MS identity shows observed mass against expected mass.
The lab is named and the report can be verified with the lab.
Net content and, where relevant, endotoxin results are reported with methods.
The listing makes no dosing, outcome, or human-use claims, and the supplier has no FDA warning letter on Tesamorelin.

Repeat the check whenever the lot changes, including on our Tesamorelin research material. Our broader peptide blend supplier guide covers GMP claims, and the Selank supplier guide applies the same method to a shorter peptide.

Frequently Asked Questions

Who are the best Tesamorelin suppliers in 2026?

The ones that can document the modified 44-residue peptide for your specific lot: named lab, HPLC with chromatogram, LC-MS identity, stated salt form, and compliant marketing. Use the checklist above on any supplier, including our Tesamorelin listing.

Is HPLC enough to confirm Tesamorelin identity?

No. HPLC measures how much of the sample sits in the main peak. Mass spectrometry shows whether that peak has the mass of Tesamorelin, hexenoyl group included.

What’s the difference between Tesamorelin and Tesamorelin acetate on a COA?

Tesamorelin is the free peptide (CAS 218949-48-5). The acetate is a salt form (CAS 901758-09-6). The COA should say which was tested and how content is reported.

How many amino acids are in Tesamorelin?

Forty-four, the full length of human GHRH(1-44), with a hexenoyl group added at the N-terminal tyrosine.

Does a “research use only” label make a Tesamorelin seller compliant?

No. FDA judges intended use from everything a seller says and sells. In August 2026 it warned sellers whose RUO-labeled Tesamorelin listings also carried outcome claims and bacteriostatic water.

Is research-grade Tesamorelin the same as the prescription product?

No. The prescription products are FDA-licensed and made under their own controls. Research material, including ours, shares the name, not the approval.

References

National Center for Biotechnology Information. PubChem Compound Summary for CID 16137828, Tesamorelin. PubChem
U.S. FDA. EGRIFTA WR (tesamorelin) prescribing information, revised March 2025. FDA
National Library of Medicine. DailyMed: EGRIFTA WR (tesamorelin) label. DailyMed
U.S. FDA. “Deemed to Be a License” Provision of the BPCI Act. FDA
U.S. FDA. ANDAs for Certain Highly Purified Synthetic Peptide Drug Products That Refer to Listed Drugs of rDNA Origin, May 2021. FDA
U.S. FDA. Q4B Annex 14: Bacterial Endotoxins Test General Chapter. FDA
U.S. FDA. FDA clarifies current thinking on pyrogen and endotoxins testing. FDA
Microbac Laboratories. What is an A2LA ISO 17025 accreditation? Microbac
Electronic Code of Federal Regulations. 21 CFR 201.128, Meaning of “intended uses.” eCFR
U.S. FDA. Warning letter to NuScience Peptides LLC, MARCS-CMS 733652, August 24, 2026. FDA
U.S. FDA. Warning letter to Royal Peptides LLC, 734884, August 24, 2026. FDA
U.S. FDA. Warning letter to Summit Research Peptides, MARCS-CMS 695607, December 10, 2024. FDA
U.S. FDA. Warning letters database. FDA
Arent Fox Schiff. RUO-ined: Five peptide vendors learn that “research use only” is not a legal strategy. 2026. AFS
Sheppard Mullin. FDA balances peptide policy with enforcement against unlawful peptide sellers. 2026. Sheppard Mullin
Federal Trade Commission. Trade Regulation Rule on the Use of Consumer Reviews and Testimonials. Federal Register, August 22, 2024. govinfo
Peptides Exchange. Certificates of Analysis. Peptides Exchange
Peptides Exchange. Tesamorelin research material listing. Peptides Exchange

For laboratory research use only. Peptides Exchange supplies Tesamorelin strictly as a laboratory material for in-vitro research by qualified professionals. It is not a drug, food, dietary supplement, or cosmetic, and it is not for human or animal use or consumption. Nothing in this article is medical or legal advice, and no product discussed is intended to diagnose, treat, cure, mitigate, or prevent any disease. Information is current as of November 7, 2026.

Article ends above.

Before you publish

These aren’t part of the article. They’re the items I couldn’t verify, plus compliance risks I found on the live site while researching.

Fill the [CONFIRM] and [ADD] cells in the Peptides Exchange table: lot number, whether the COA prints observed mass, endotoxin status. If the answer is “no,” say so in the cell rather than deleting the row.
Add sequence, CAS, formula, and salt form to the Tesamorelin product page. The article holds suppliers to that standard, and our listing doesn’t meet it yet.
The 20 mg COA reports 26.63 mg net content, about 133% of nominal. Readers will notice. Check with Freedom Diagnostics whether that figure is peptide or salt, and whether fill is controlled.
Bacteriostatic water on the site is the biggest risk. The CJC-1295 + Ipamorelin page shows bacteriostatic water under Related products. FDA cited exactly that pairing in the August 24, 2026 NuScience letter that named Tesamorelin. Consider removing it from the catalog, or at minimum from related-product carousels on peptide pages.
Review “What Is Tesamorelin?” before linking it heavily. It summarizes visceral-fat and liver-fat trial outcomes. FDA quoted very similar clinical-outcome language from NuScience’s Tesamorelin page as evidence of intended human use, even with disclaimers. Moving that content to a neutral “published literature” framing, or trimming it, lowers risk.
PubChem links. FDA’s NuScience letter quoted pharmacology text from a PubChem page the seller linked. The links here go to the main compound record for identifiers only, which is lower risk, but you may prefer to cite identifiers without linking.
Why this article doesn’t cover compounding status. Secondary sources disagree on where Tesamorelin stands on FDA’s 503A lists after the April 2026 changes. Leaving it out avoids a claim we can’t pin to an FDA page.

Not legal advice. For a site selling an active ingredient of an FDA-licensed product, a one-time review by an FDA regulatory attorney is worth the cost.

Best Tesamorelin Research Suppliers in 2026: COAs and Identity Verification