ARA-290 Research: Cibinetide, pHBSP, and Evidence Limits
ARA-290 Research: Cibinetide, pHBSP, and Evidence Limits
A source-led guide to the erythropoietin-derived peptide ARA-290, its proposed innate repair receptor, preclinical models, and small human trials.
ARA-290 research spans peptide design, injury models, and early trials
ARA-290, also called cibinetide or pyroglutamate helix-B surface peptide, is an 11-amino-acid peptide modeled on part of erythropoietin's helix-B surface. It was designed to study tissue-protective signaling without stimulating red-blood-cell production.
Researchers propose that it signals through an innate repair receptor involving EPOR and CD131. Preclinical work has examined inflammation, nerve injury, ischemia, and tissue protection.
Small human trials have focused on symptoms or surrogate nerve measures. They are useful translational signals, but they do not establish broad nerve repair, tissue repair, or long-term safety.
What researchers are trying to understand
Why does ARA-290 have several names?
ARA-290 and cibinetide are commonly connected with pHBSP, shorthand for a pyroglutamate helix-B surface peptide. A page should introduce the synonyms and then use one name consistently.
What is the proposed innate repair receptor?
It is a proposed receptor complex involving the erythropoietin receptor and CD131, studied separately from signaling most associated with red-blood-cell production.
What do the human studies actually measure?
The small trials use symptom scores and measures such as corneal nerve-fiber area. A surrogate change is not automatic proof of restored function or clinical benefit.
Notable studies, in plain English
The studies below are separated by model and design so that early laboratory signals are not confused with evidence from people.
Helix-B peptide design and tissue-protection models
- Model
- Cell and receptor work plus rat and mouse nerve, ischemia, and retinal-injury models
- Design
- Multi-model preclinical peptide-design study
What the paper reported: Helix-B-surface-derived peptides showed protective activity in several injury models without hematopoietic activity in the tested systems.
Important limit: Multiple positive preclinical models do not establish broad tissue repair in people.
Exploratory sarcoidosis small-fiber-neuropathy trial
- Model
- 22 people with sarcoidosis-associated small-fiber neuropathy
- Design
- Randomized double-blind placebo-controlled exploratory trial
What the paper reported: The study reported a signal on a symptom questionnaire, while several pain measures improved in both groups.
Important limit: The sample was small and follow-up was short, so the result is not definitive.
Phase 2 painful-neuropathy trial in type 2 diabetes
- Model
- Adults with type 2 diabetes and painful neuropathy
- Design
- Double-blind, placebo-controlled phase 2 trial
What the paper reported: The short study explored symptom and metabolic measures and reported several exploratory signals.
Important limit: It was small and was not a definitive efficacy or long-term safety trial.
Phase 2b sarcoidosis small nerve-fiber trial
- Model
- 64 people with sarcoidosis-associated small nerve-fiber loss
- Design
- Randomized placebo-controlled phase 2b trial
What the paper reported: One study group showed improvement in corneal nerve-fiber area, a surrogate measure; pain improved across groups.
Important limit: The placebo-corrected pain result was not statistically significant, and a surrogate nerve measure is not proof of clinical recovery.
ARA-290 in experimental autoimmune neuritis
- Model
- Rat neuritis model plus Schwann-cell and immune-cell experiments
- Design
- Controlled animal study with supporting cell work
What the paper reported: ARA-290 was associated with lower model severity, altered inflammatory signaling, and measures of regeneration or remyelination.
Important limit: The work is preclinical and the article has a published correction.
What the evidence does—and does not—establish
Preclinical injury models do not prove broad nerve repair or tissue repair in people. The cited human trials are small, short, and indication-specific, and corneal nerve-fiber area is a surrogate rather than automatic evidence of symptom relief or restored function.
Nonerythropoietic describes a design objective and findings in tested systems; it does not mean risk-free. Published results also do not show that every commercially sold ARA-290 material matches the identity, purity, formulation, or biological behavior of study material.
- ARA-290 is also searched as cibinetide and pHBSP.
- The proposed mechanism involves an EPOR/CD131 innate repair receptor.
- Preclinical models are broader than the small human evidence base.
- Human trials rely partly on symptoms and surrogate nerve measures.
- No broad repair or long-term safety conclusion is established.
Where to buy ARA-290 for laboratory research in the USA
A research listing should disclose the 11-amino-acid sequence, molecular identity, purity method and result, lot-specific COA, physical form, and intended laboratory use. It should also explain the ARA-290, cibinetide, and pHBSP naming relationship without assuming undocumented equivalence.
Commercial phrases such as buy ARA-290 research peptide or cibinetide supplier USA should remain in a procurement context. Avoid coupling them to nerve repair, pain, tissue repair, dosing, administration, or human-outcome claims.
Searches such as “where to buy ARA-290,” “buy ARA-290 USA,” and “USA peptides” should be treated as laboratory-sourcing questions. Compare U.S. research suppliers by lot traceability, identity testing, quantitative-content information, analytical methods, and stated research-use restrictions—not by implied human outcomes.
ARA-290 research FAQ
Are ARA-290, cibinetide, and pHBSP the same search topic?
They are closely linked names used for this helix-B-surface-derived peptide. Introduce all three terms and then use one consistently.
What is the proposed innate repair receptor?
It is a proposed receptor complex involving EPOR and CD131, studied separately from red-blood-cell-related erythropoietin signaling.
Do the human trials prove nerve regeneration?
No. They were small and used symptom scores or surrogate measures such as corneal nerve-fiber area.
What does nonerythropoietic mean?
It means the peptide was designed and studied without the red-blood-cell-stimulating activity associated with erythropoietin in tested systems; it does not mean risk-free.
What documentation should accompany research-grade ARA-290?
Sequence, identity testing, purity method and result, lot-specific COA, physical form, and a clear laboratory-research limitation.
Primary references
References link to the original journal record or publisher page. Inclusion is not an endorsement of a product or a clinical conclusion.
- Brines et al. (2008). PMID 18676614; PMCID PMC2504825. DOI 10.1073/pnas.0805594105.
- Heij et al. (2012). PMID 23168581; PMCID PMC3563705. DOI 10.2119/molmed.2012.00332.
- Brines et al. (2015). PMID 25387363; PMCID PMC4365069. DOI 10.2119/molmed.2014.00215.
- Culver et al. (2017). PMID 28475703. DOI 10.1167/iovs.16-21291.
- Liu et al. (2014). PMID 24603865. DOI 10.1371/journal.pone.0090942.