Tesamorelin is one of the most searched growth hormone-releasing hormone (GHRH) analogues among South African research labs, and it sits alongside CJC-1295 as one of the best-known modified GHRH peptides. If you have been searching for "Tesamorelin South Africa", this guide covers the essentials: what Tesamorelin is, how its structure differs from native GHRH, what published laboratory research has looked at, how the vial and pen formats compare, and how to store it and check its certificate of analysis.
Researchers comparing GHRH analogues can also look at the CJC-1295 Peptide Pen, and every GHRH and GHS peptide we stock is listed in our peptides South Africa collection.
What is Tesamorelin?
Tesamorelin (development code TH9507) is a synthetic 44-amino-acid peptide. Its sequence is identical to the full length of human GHRH, the hypothalamic peptide also called somatoliberin or growth hormone-releasing factor (GRF 1–44). The one deliberate change is chemical: a trans-3-hexenoyl group is attached to the tyrosine at position 1, the N-terminus of the chain.
That small addition matters. Native GHRH is cleaved quickly by dipeptidyl peptidase-4 (DPP-4), an enzyme that removes the first two amino acids from the N-terminus. The hexenoyl cap is designed to block that cleavage. In the non-clinical pharmacology work published on TH9507, the modified peptide degraded more slowly than unmodified GHRH in rat, dog and human plasma in vitro.
Tesamorelin structure and specifications
The physical data below match the PubChem record for Tesamorelin (CID 16137828) and the specifications on our product pages. The underlying sequence is the mature human GHRH peptide listed in UniProt (entry P01286), which ends in a C-terminal leucine amide.
(trans-3-hexenoyl)-YADAIFTNSYRKVLGQLSARKLLQDIMSRQQGESNQERGARARL-NH2
Key specifications at a glance
- Length: 44 amino acids, linear, C-terminal amide
- N-terminal modification: trans-3-hexenoyl group on Tyr1
- Molecular formula: C221H366N72O67S
- Molecular weight: about 5,136 g/mol
- CAS number: 218949-48-5
- Research material: synthetic peptide supplied as a lyophilised (freeze-dried) powder or as a ready-made solution in a pre-filled pen
- Sulfur content: one methionine (position 27), which can oxidise if the material is exposed to air, light and heat
At roughly 5.1 kDa, Tesamorelin is a large peptide compared with short sequences such as BPC-157 or Semax. That size has practical consequences in the lab: identity is usually confirmed by mass spectrometry looking at multiply charged ions, and a methionine oxidation shows up as an extra 16 Da on the measured mass.
Tesamorelin vs CJC-1295: what is the difference?
Both are modified GHRH analogues built to resist enzymatic breakdown, but they take different approaches.
- Tesamorelin keeps the full 44-amino-acid GHRH sequence and adds a single N-terminal hexenoyl cap.
- CJC-1295 (also called modified GRF 1–29) uses only the first 29 amino acids and swaps four of them for more stable residues. The DAC version adds a reactive linker designed to bind albumin.
Our CJC-1295 + Ipamorelin guide covers those peptides in detail, and the CJC-1295 + Ipamorelin blend is available if your work compares GHRH analogues side by side.
What has Tesamorelin been studied for in the lab?
Tesamorelin has a substantial published literature, including clinical studies. That literature is described here only as scientific background. It is not evidence of any effect of the research material we supply, and nothing below is a claim of benefit.
Enzymatic stability and pharmacology
The main non-clinical paper on the compound (Ferdinandi et al., 2007, Basic & Clinical Pharmacology & Toxicology, PMID 17214611) reported that the hexenoyl modification made TH9507 resistant to DPP-4 inactivation and slowed its breakdown in plasma compared with native GHRH. In rat, dog and pig models, the authors measured changes in circulating growth hormone and insulin-like growth factor-1 (IGF-1), the two standard markers in GHRH-receptor research. The same paper also documents toxicology findings in dogs, which the authors linked to prolonged exposure to high growth hormone and IGF-1 levels.
Delivery-route research
Formulation scientists have looked at how a peptide this size behaves by different routes. A 2004 study in the International Journal of Pharmaceutics (Jansen et al., PMID 15113616) compared dry-powder delivery into the airway with subcutaneous delivery in dogs, measuring plasma levels, half-life and mean residence time. It is a useful reference for anyone working on large-peptide formulation and absorption.
Receptor pharmacology
Because Tesamorelin keeps the native GHRH sequence, it is also used as a reference compound in GHRH-receptor studies, for example when comparing full-length analogues with shortened 1–29 sequences or with ghrelin-receptor peptides such as ipamorelin.
Tesamorelin formats in South Africa: vial or pen?
Biolabs supplies Tesamorelin in two formats, each in 10 mg and 20 mg strengths. The compound is the same; the format decides how it is shipped, stored and prepared.
Lyophilised vial
The Tesamorelin lyophilised vial is the most stable option for storage and shipping, because freeze-drying removes the water that drives most peptide degradation. It ships by tracked courier and needs reconstituting before use. Solvents and accessories are in our reconstitution supplies and hardware collection, and the rest of the range is in our peptide vials collection.
Pre-filled pen
The Tesamorelin Peptide Pen holds a ready-made solution, so there is no reconstitution step. Pens are made to order, must stay refrigerated at 2–8 °C and go out by overnight cold-chain courier. If you are in an area without reliable overnight delivery, choose the vial. You can compare the full range in our pre-filled peptide pens collection, and our pens vs vials guide explains the trade-offs in more detail.
Storage and lab handling for Tesamorelin
Lyophilised powder
Store unopened vials at −20 °C for long-term storage or 2–8 °C for shorter periods, away from light and moisture. Sealed vials handle normal courier transit at ambient temperature. Let a vial reach room temperature before you open it, so condensation does not form on the powder.
Reconstitution
Laboratories typically use sterile water or bacteriostatic water (0.9% benzyl alcohol). Larger peptides can foam or stick to glass if handled roughly, so add the solvent slowly down the inside wall of the vial and swirl gently rather than shaking. Label the vial with the date and concentration, keep the solution at 2–8 °C and follow your own validated protocol for how long it remains usable. Our bacteriostatic water guide compares the common solvents.
Pens
Keep pens refrigerated at 2–8 °C, protected from light and never frozen. Limit time at room temperature during handling, since the methionine residue can oxidise over time.
Reading a Tesamorelin COA
Every Biolabs batch is tested by an independent laboratory for purity (HPLC) and identity (mass spectrometry). When you review a Tesamorelin certificate, check that:
- the batch or lot number matches the number on your vial or pen,
- the HPLC purity is shown with a chromatogram, not only a single figure,
- the measured mass is consistent with about 5,136 g/mol, with no unexplained +16 Da peak, and
- the test date and the name of the testing laboratory are stated.
Certificates are published on our Certificates of Analysis page, so you can check a batch before you order.
Tesamorelin FAQ
Where can I buy Tesamorelin in South Africa?
Biolabs ships Tesamorelin nationwide from local stock. Vials go by tracked courier and pens go by overnight cold-chain courier.
Is Tesamorelin the same as GHRH?
It has the same 44-amino-acid sequence as human GHRH, plus an N-terminal trans-3-hexenoyl group that native GHRH does not have. That cap is what makes it more resistant to DPP-4 breakdown.
Which format is more stable?
The lyophilised vial. Freeze-dried peptides keep far longer than solutions, which is why the vial is recommended for long-term storage or for areas without overnight courier delivery.
Is Tesamorelin for human use?
No. The Tesamorelin we supply is sold strictly for laboratory research and is not for human or veterinary use.
Sources
- PubChem compound summary: Tesamorelin, CID 16137828 (formula, molecular weight, CAS number).
- UniProt entry P01286, human somatoliberin (GHRH) mature peptide sequence.
- Ferdinandi ES et al. Non-clinical pharmacology and safety evaluation of TH9507, a human growth hormone-releasing factor analogue. Basic Clin Pharmacol Toxicol. 2007;100(1):49-58. PMID 17214611.
- Jansen M et al. Pulmonary delivery of TH9507, a growth hormone releasing factor analogue, in the dog. Int J Pharm. 2004;276(1-2):75-81. PMID 15113616.
Research use only: All Biolabs products, including Tesamorelin in every format, are supplied strictly for laboratory research by qualified researchers. They are not for human or veterinary use, not for consumption, and are not medicines, foods, supplements or cosmetics. Nothing in this article is medical advice or a claim of any effect. Research summaries describe published studies only and do not describe the products we sell. The purchaser is responsible for safe handling and for complying with applicable South African regulations.