ARA-290

ARA-290 is a synthetic 11-residue peptide, assigned the international nonproprietary name cibinetide, whose sequence corresponds to the aqueous-facing surface of helix B of erythropoietin. The sequence is Pyr-Glu-Gln-Leu-Glu-Arg-Ala-Leu-Asn-Ser-Ser, carrying an N-terminal pyroglutamate in place of glutamine, which is the origin of the alternative name pyroglutamate helix B surface peptide, or pHBSP. It carries the molecular formula C51H84N16O21 and a molecular weight of 1257.3 g/mol, and appears in PubChem as CID 91810664 under CAS number 1208243-50-8. It is also written ARA 290 without a hyphen. Laboratory material is supplied as a lyophilized (freeze-dried) solid.

ARA-290 was engineered at Araim Pharmaceuticals to separate the tissue-protective signalling attributed to erythropoietin from the hormone’s effect on red blood cell production. Because it reproduces a surface region of the folded protein rather than the receptor-binding interface, the literature describes it as non-erythropoietic. ARA-290 reached early clinical study under the name cibinetide, no regulatory approval followed, and Araim Pharmaceuticals has ceased operations, so the compound is now a research reagent only. Identity figures above should be reconciled against the Certificate of Analysis for the lot in hand. ARA-290 is sold for research use only and is not for human or veterinary use.

ARA-290 was first described in 2008, when Brines and colleagues reported peptides derived from the tertiary structure of erythropoietin that retained tissue-protective signalling in animal models without stimulating erythropoiesis (PubMed 18676614).

Swartjes and colleagues studied the peptide in rats and in beta-common receptor knockout mice, using the knockout to test receptor dependence (PubMed 21873879). Nairz and colleagues examined innate immune cell function in a murine colitis model (PubMed 29026145).

The preclinical record spans several organ systems, but much of it comes from groups connected to the original developers, and independent replication is limited.

The literature describes ARA-290 as an agonist at a heteromeric complex of the erythropoietin receptor and the beta-common receptor (CD131), which the original authors named the innate repair receptor. Downstream signalling reported in animal models includes the JAK2/STAT3 and PI3K/Akt pathways (PubMed 25728128).

ARA-290 is not an erythropoietin substitute: reports describe no erythropoietic effect, and it is not described as engaging the homodimeric erythropoietin receptor that drives red cell production.

Receptor identity remains debated: the innate repair receptor has not been isolated as a discrete molecular species, and much supporting evidence is genetic, resting on loss of effect in knockout animals (PubMed 21873879).

Sealed lyophilized ARA-290 is held frozen at -20°C, shielded from light, in its original container. Lyophilized peptides are hygroscopic, so a container reaches ambient temperature before opening. Repeated freeze-thaw cycles are avoided.

Stability for a lot is documented on its Certificate of Analysis rather than assumed here.

Reconstitution means returning a lyophilized compound to solution. This entry gives no preparation procedure: solvent, concentration and handling steps belong to a protocol, not to the compound. ARA-290 is a short, strongly polar sequence and is handled as aqueous-soluble material.

Asparagine residues make deamidation a recognised degradation route for sequences of this class. Solubility and water-content figures for a lot appear on its Certificate of Analysis.

Identity and purity of research-grade ARA-290 are established analytically, typically by reverse-phase HPLC and mass spectrometry. Verified purity is documented per lot on the Certificate of Analysis. The pyroglutamate N-terminus is the specification detail most worth checking, because a sequence carrying free glutamine at position 1 is a different molecule with a different mass and is a plausible synthesis by-product.

Counter-ion content, commonly trifluoroacetate or acetate, shifts effective peptide mass. Confirm the salt form and mass on each lot’s COA.

ARA-290 is catalogued alongside these encyclopedia compounds.

• MOTS-c.
  Endogenously derived peptide investigated in metabolic and insulin-sensitivity models.
• BPC-157.
  Pentadecapeptide investigated in animal tissue-repair models.
• Thymosin Alpha-1.
  28-residue peptide studied in immune-signalling models.
• Semax.
  ACTH-derived peptide studied in neural models.

Brines M, Patel NS, et al. (2008). Nonerythropoietic, tissue-protective peptides derived from the tertiary structure of erythropoietin. Proc Natl Acad Sci U S A.
PubMed 18676614

Swartjes M, Morariu A, et al. (2011). ARA290, a peptide derived from the tertiary structure of erythropoietin, produces long-term relief of neuropathic pain: an experimental study in rats and beta-common receptor knockout mice. Anesthesiology.
PubMed 21873879

Nairz M, Haschka D, et al. (2017). Cibinetide dampens innate immune cell functions thus ameliorating the course of experimental colitis. Scientific Reports.
PubMed 29026145

Collino M, Thiemermann C, et al. (2015). Flipping the molecular switch for innate protection and repair of tissues: long-lasting effects of a non-erythropoietic small peptide engineered from erythropoietin. Pharmacol Ther.
PubMed 25728128

ARA-290 is stocked here in one format: sealed single-compound lyophilized vials from two supplier brands, listed at 12mg and 10mg fills. Vials are the only listed format for this compound in this catalog. Per-vial strengths are product specifications only. Each lot is batch tested with a published Certificate of Analysis documenting verified purity and identity for that specific lot.

• Browse all ARA-290 research products
• Verified Peptides ARA-290, 12mg lyophilized vial
• Real Peptides ARA-290, 10mg lyophilized vial
• Collections: Research Vials. Documentation: COA and Lab Testing.

These products are sold for Research Use Only and are not intended for human consumption.