| Product Name | Abarelix |
| Synonyms | Plenaxis, PPI-149, R-3827 |
| CAS Number | 183552-38-7 (free base); acetate salt 785804-17-3 |
| Sequence (3-Letter) | Ac-D-Nal(2)-D-Phe(4-Cl)-D-Pal(3)-Ser-N-Me-Tyr-D-Asn-Leu-Lys(iPr)-Pro-D-Ala-NH₂ |
| Sequence (1-Letter) | Ac-[D-2Nal]-[D-4ClPhe]-[D-3Pal]-S-[NMe-Y]-[D-Asn]-L-[K(iPr)]-P-[D-Ala]-NH₂ |
| Molecular Formula | C₇₂H₉₅ClN₁₄O₁₄ (free base) |
| Molecular Weight | 1416.06 (free base) |
| Category | Drug Peptide – GnRH Antagonist |
| Purity | ≥98% (by HPLC) |
| Appearance | White to off-white powder |
| Counter Ion | Acetate (salt form per specification) |
| Peptide Content | ≥80% (per specification) |
| Solubility | Soluble in water and DMSO |
| Storage | -20°C, desiccated, protected from light |
| Available Scale | mg – kg (research quantities to scale-up batches) |
| QC Documentation | COA, HPLC, MS identity (additional API/regulatory documentation on request) |
| Usage | For research and pharmaceutical development use, and as a reference standard or active pharmaceutical ingredient for manufacturing. Not for human or veterinary use; not for sale to patients. Any therapeutic use is subject to applicable regulatory approval. |
Abarelix is a synthetic decapeptide and a gonadotropin-releasing hormone (GnRH) antagonist, known as a medicine under the brand name Plenaxis (CAS 183552-38-7; acetate salt 785804-17-3). It was the first GnRH antagonist brought to market. It is an analog of natural GnRH with several non-natural and D-amino acid substitutions and an acetyl group at the N-terminus. We supply it as a white powder for research and pharmaceutical development.
Abarelix is a GnRH antagonist. It binds the GnRH receptor in the pituitary directly and blocks it, so the pituitary immediately releases less LH and FSH, and the body makes less testosterone. Unlike a GnRH agonist, it does this without an initial surge of hormones, so there is no early rise in testosterone and no associated flare.
Clinically, abarelix has been used in advanced prostate cancer to lower testosterone, a hormone that drives prostate growth. This is background information only; the material we supply is for research and pharmaceutical manufacturing use, and is not for human or veterinary use and not for sale to patients.
We supply Abarelix with a certificate of analysis, HPLC purity data, and mass-spec identity confirmation. Additional documentation for API and regulatory work is available on request, and salt form and purity can be set to your specification.
Yes. We manufacture Abarelix in-house and supply from research quantities up to scale-up batches. With its several non-natural amino acids it is a demanding synthesis, and we can discuss the right approach for your scale. Contact us with your required purity and quantity for a quote.
Abarelix is a synthetic decapeptide and a gonadotropin-releasing hormone (GnRH) antagonist, and was the first GnRH antagonist to reach the market. It is known as a medicine under the brand name Plenaxis. We supply it as a raw material for research and pharmaceutical development.
Abarelix is a ten-residue peptide based on natural GnRH but heavily modified: it carries several non-natural and D-amino acids, including an N-methyl-tyrosine and an isopropyl-lysine, an acetyl group at the N-terminus, and a C-terminal amide. These changes give it antagonist activity and stability. Its free-base CAS number is 183552-38-7 (acetate salt 785804-17-3), its molecular formula is C72H95ClN14O14, and its molecular weight is about 1416.
Abarelix is a GnRH receptor antagonist. It binds the GnRH receptor in the pituitary directly and blocks it, so the pituitary quickly produces less luteinising hormone (LH) and follicle-stimulating hormone (FSH), and the testes make less testosterone. This is the opposite approach to a GnRH agonist such as a goserelin-type drug, which first stimulates the pituitary; like the other GnRH antagonist cetrorelix, abarelix suppresses hormone output immediately, without the initial testosterone surge.
Abarelix has been used clinically in advanced prostate cancer to lower testosterone, the hormone that drives prostate growth, particularly where the early hormone surge seen with agonists is best avoided. This information is provided as scientific and reference background only. The material supplied by SynPeptide is intended for research and pharmaceutical manufacturing, is not for human or veterinary use, and is not for sale to patients; any therapeutic use is subject to applicable regulatory approval.
Because abarelix contains several non-natural residues, it calls for careful synthesis and purification. We supply it with a certificate of analysis, HPLC purity data, and mass-spectrometry identity confirmation, with further documentation available to support active pharmaceutical ingredient and regulatory work, and purity and salt form set to your specification.
We manufacture Abarelix by solid-phase synthesis, including its non-natural and D-amino acid residues, and supply it from research quantities through to scale-up batches. For related capabilities, see drug peptides, custom peptide synthesis, and peptide modification. Material is supplied for research and pharmaceutical manufacturing use only.
