Health & Research Goals
ARA-290
ARA-290 (Cibinetide — Innate Repair Receptor Agonist)
Primary Description
ARA-290, also known as Cibinetide, is a synthetic 11-amino acid peptide engineered from the helix-B domain of erythropoietin (EPO). It was deliberately designed to activate only the EPO/CD131 heterodimeric Innate Repair Receptor (IRR) — which drives tissue protection, nerve regeneration, and anti-inflammatory signaling — while having zero activity at the classical EPO homodimer responsible for red blood cell production. This makes it fundamentally different from EPO itself: no hematopoietic risk, no blood thickening, but strong tissue-repair and neuroprotective properties. ARA-290 has completed Phase 2 clinical trials in sarcoidosis-associated small fiber neuropathy and diabetic neuropathy — two conditions with few effective treatment options.
Key Benefits
- Neuropathic pain relief via EPOR/BMXR receptor (non-erythropoietic EPO fragment)
- Anti-inflammatory tissue protection without stimulating red blood cell production
- Peripheral nerve repair and small-fiber neuropathy support
Contains N-terminal pyroglutamate modification that enhances stability. Lyophilized powder stable for extended periods at -20°C. Short plasma half-life (~20 minutes following sub-Q injection) but downstream gene expression changes persist for many hours, supporting once-daily dosing. Reconstituted solution should be stored at 2–8°C and used within 28 days.
Demonstrated Effects
- Activates the Innate Repair Receptor (IRR) to initiate tissue protection and neural repair signaling
- Demonstrated 23% increase in corneal nerve fiber abundance at 4 mg dose in Phase 2b trial
- Clinically meaningful reduction in neuropathic pain in sarcoidosis patients with small fiber neuropathy
- Improved HbA1c and lipid profiles in type 2 diabetic neuropathy patients during Phase 2 trial
- Immunomodulatory (not immunosuppressive) — reduces pro-inflammatory cytokines without shutting down immune defense
- Inhibits NF-κB signaling, TNF-α, and IL-6 production — potent anti-inflammatory without steroid-like risks
- Supports mitochondrial function and reduces oxidative stress in neurons
- Does not stimulate red blood cell production — no erythropoiesis risk
Proposed Mechanisms of Action
1. Innate Repair Receptor (IRR) Activation
ARA-290 selectively binds and activates the EPOR/CD131 heterodimeric Innate Repair Receptor — a complex distinct from the classical EPOR homodimer. The IRR is locally upregulated at sites of tissue injury and mediates a repair-and-protect response when activated.
The foundational mechanism — everything downstream depends on IRR activation. No activity at the classical EPO receptor means no erythropoiesis stimulation.
2. Pro-Inflammatory Cytokine Suppression (NF-κB Inhibition)
IRR activation inhibits NF-κB signaling — a master regulator of inflammatory gene transcription. This reduces production of TNF-α, IL-6, IL-1β, and other pro-inflammatory cytokines. Critically, this is immunomodulatory (calming excessive inflammation) rather than immunosuppressive (shutting down immune defense).
Addresses the neuroinflammatory component of neuropathy and chronic inflammatory conditions without the infection-risk profile of steroids or biologics.
3. Anti-Apoptotic and Neuronal Survival Signaling
ARA-290 activates PI3K/Akt and MAPK/ERK survival pathways downstream of IRR, suppressing apoptotic cascades in neurons and supporting axonal maintenance and regrowth. Mitochondrial protection reduces oxidative damage in nerve fibers.
Directly supports nerve fiber survival and regeneration — the basis for corneal nerve fiber density increases observed in clinical trials.
4. Macrophage Polarization (M1 to M2 Shift)
ARA-290 modulates macrophage activity, shifting inflammatory M1 macrophages toward anti-inflammatory, repair-promoting M2 phenotype. This regulatory effect reduces chronic neuroinflammation while preserving functional immune surveillance.
Sustains the anti-inflammatory environment needed for nerve regeneration to proceed without immune interference.
Research Evidence & Clinical Data
Investigated Applications
Peripheral Neuropathy (Diabetic and Sarcoid-Associated)
Anecdotal: ModerateThe most clinically validated application for ARA-290 and the primary reason biohackers and patients with chronic neuropathy explore it. Phase 2b data showed nerve fiber regeneration (corneal nerve density increase) and pain reduction in small fiber neuropathy — conditions where conventional medicine offers limited disease-modifying options. Community users with diabetic neuropathy or post-infection nerve damage report pain reduction and improved sensation within 4–8 weeks of a 28-day course.
Preclinical basis: Phase 2b randomized trial (64 subjects): 4 mg cibinetide produced 23% increase in corneal nerve fiber abundance vs. placebo. Phase 2 diabetic neuropathy trial: improved PainDetect scores, HbA1c, and lipid profiles. Multiple IRR-mediated nerve repair mechanisms confirmed in cell and animal models.
Systemic Inflammation and Autoimmune Conditions
Anecdotal: EmergingARA-290's immunomodulatory profile — suppressing pro-inflammatory cytokines while preserving immune defense — makes it interesting for chronic inflammatory conditions including sarcoidosis, lupus, and other autoimmune-mediated neuropathies. Community interest has grown particularly following the Long COVID era, where small fiber neuropathy and dysautonomia have become prevalent without adequate treatment options.
Preclinical basis: Sarcoidosis Phase 2 trials directly address autoimmune-mediated neuropathy. Preclinical models of multiple sclerosis, inflammatory arthritis, and organ ischemia all show protective IRR-mediated effects.
Metabolic Health — Insulin Sensitivity and Glucose Regulation
Anecdotal: EmergingA secondary but clinically validated benefit. In the Phase 2 diabetic neuropathy trial, patients showed improved HbA1c and lipid profiles over 56 days — effects that extended beyond the 28-day treatment period. This suggests ARA-290 may have lasting metabolic benefits through nerve-mediated glucose regulation and anti-inflammatory effects on insulin-sensitive tissues.
Preclinical basis: Phase 2 trial data: ARA-290 group showed significant improvements in HbA1c and lipid profiles at days 28 and 56 compared to placebo. IRR activation in pancreatic islets may contribute to improved insulin function.
Tissue Protection Post-Injury (Organ Ischemia, Burns, TBI)
Anecdotal: LimitedIn preclinical models, ARA-290 has shown remarkable tissue-protective effects in acute injury scenarios — myocardial infarction, kidney ischemia, traumatic brain injury, burns, and shock-induced multi-organ failure. Community exploration in this area is extremely limited given the acute/emergency nature of these applications, but researchers are interested in the potential for prophylactic or early post-injury use.
Preclinical basis: Multiple preclinical studies demonstrate IRR-mediated organ protection: prevents apoptosis, reduces inflammation, and activates repair in cardiac, renal, CNS, and hepatic ischemia models.
Scientific References
- 1.Brines et al. (2014). ARA 290, a Nonerythropoietic Peptide Engineered from Erythropoietin, Improves Metabolic Control and Neuropathic Symptoms in Patients with Type 2 DiabetesMolecular Medicine (PMC)2014
Phase 2 trial in type 2 diabetic neuropathy: 4 mg sub-Q daily for 28 days improved PainDetect scores, HbA1c, and lipid profiles compared to placebo. Effects observed through day 56.
- 2.MedChemExpress — Cibinetide (ARA290) Chemical DataMedChemExpress Reference Database2024
Verified molecular formula C51H84N16O21, MW 1257.3 g/mol, CAS 1208243-50-8, and amino acid sequence ZEQLERALNSS with N-terminal pyroglutamate.
Safety Profile
Common Side Effects
- Mild injection site reactions (redness, soreness) — most common reported effect
- Headache (mild, reported in some trial participants)
- Mild fatigue during early treatment phase
- No dose-limiting toxicity identified in Phase 2 trials across all dose levels
- No erythropoiesis stimulation — no risk of polycythemia or blood thickening
Contraindications
- Active cancer or hematological malignancy — EPO-derived peptide warrants caution despite absent erythropoiesis activity
- Current use of anticoagulants — theoretical consideration given EPO-pathway origins (monitor closely)
- Pregnancy or breastfeeding — insufficient safety data
- Known hypersensitivity to erythropoietin or erythropoietin-derived compounds
- Competitive athletes under WADA testing — prohibited substance
Pre-Use Screening Checklist
Baseline hematological status. Although ARA-290 does not stimulate erythropoiesis, EPO-derived peptide origin warrants a baseline CBC, particularly hemoglobin and hematocrit.
EPO receptor-related signaling has theoretical relevance to some cancers. Absence of clinical erythropoiesis effect is reassuring, but caution is warranted in oncology history contexts.
Documenting pre-treatment neuropathy severity (pain scores, sensation assessment) is essential for evaluating response to treatment.
WADA prohibited — EPO-derived compound banned in and out of competition for athletes subject to anti-doping rules.
Legal & Regulatory Status
Not FDA-approved. Investigational New Drug (IND) status under Araim Pharmaceuticals during clinical development. Phase 2 completed; Phase 3 not initiated. Research peptide classification. Not approved for human therapeutic use in the US.
Prohibited — EPO-derived peptide classified under S2 (Peptide Hormones, Growth Factors, Related Substances and Mimetics) or S0. Banned in and out of competition for athletes subject to WADA code, despite absence of erythropoietic activity.
No specific COFEPRIS ruling. Available as research peptide. Not approved as a pharmaceutical.
Received EMA Orphan Drug Designation for sarcoidosis-associated neuropathy during clinical development. Not approved as a therapeutic product. Research use only.
Not TGA-approved. Research chemical or Schedule 4 substance depending on formulation context. Clinical trial work was conducted in part in European centers.
Research Protocols
Dosing Protocols
Neuropathy treatment (Phase 2 validated protocol)
Subcutaneous injectionSarcoidosis / IV protocol (clinical trial reference)
Intravenous (clinical trial setting only — sub-Q preferred for community use)Routes of Administration
Subcutaneous injection
Most commonStandard sub-Q injection into abdominal fat fold. Use 29–31 gauge insulin syringe. This is the preferred route for self-administration based on Phase 2b trial protocols.
Rotate injection sites. Morning injection common but timing is flexible given the mechanism of action (not dependent on fasted state). Short plasma half-life (~20 min) but prolonged downstream effects support once-daily dosing.
Reconstitution Guide
Bacteriostatic water (preferred) or sterile water for injection
Add bacteriostatic water slowly to lyophilized powder. Do not shake — gently swirl until fully dissolved. Solution should be clear. Given the 4 mg daily dose, a higher concentration per vial is often convenient.
16 mg vial + 4 mL bacteriostatic water = 4 mg/mL. To draw 4 mg: pull 1.0 mL (100 units on a 100-unit insulin syringe). Alternatively: 16 mg + 2 mL = 8 mg/mL; 4 mg = 0.5 mL.
Refrigerate at 2–8°C. Use within 28 days. Do not freeze. Label with reconstitution date.
Lyophilized powder: -20°C freezer for long-term. 2–8°C refrigerator for up to 3 months.
Timing of injection is not critical relative to meals given the mechanism (not a metabolic peptide dependent on insulin state). Morning or evening administration are both acceptable. Consistent daily timing within the 28-day cycle is recommended for stable IRR activation.
Pharmacokinetics
| Half-Life | Terminal plasma half-life approximately 20 minutes following 4 mg sub-Q injection (peak ~3 ng/mL). Some sources report a half-life as short as 2 minutes in certain assay conditions. Despite rapid clearance, downstream gene expression and repair pathway activation from a single dose persist for many hours — supporting once-daily dosing and even persistent effects beyond the treatment period. |
| Absorption | Sub-Q route: peak plasma level ~3 ng/mL achieved following 4 mg SC. PK data confirms systemic absorption sufficient to achieve plasma concentrations exceeding the 1 nmol/L threshold required for IRR activation. IV route also used in clinical trials. |
| Distribution | IRR is expressed at sites of tissue injury — upregulated locally following damage. ARA-290 binds these peripheral IRR complexes to initiate local repair responses. CNS penetration not well characterized but neurological effects suggest access to peripheral nervous system. |
| Metabolism | Standard peptide catabolism by circulating peptidases. N-terminal pyroglutamate modification provides some resistance to aminopeptidase degradation. Metabolized to constituent amino acids. |
| Molecular Structure | 11-amino acid peptide with N-terminal pyroglutamate (Z): Z-Glu-Gln-Leu-Glu-Arg-Ala-Leu-Asn-Ser-Ser. MW: 1,257.3 g/mol. CAS: 1208243-50-8. Derived from the EPO helix-B surface — the region responsible for tissue-protective signaling distinct from the hematopoietic activation domain. |
Monitoring & Risk Management
Ongoing Monitoring Steps
- Neuropathic pain and sensory symptomsTrack pain scores, tingling, numbness, and functional capacity. Phase 2 data suggests meaningful improvement in moderate-to-severe pain subgroups. Partial responders may benefit from a second course.Check: Weekly during 28-day cycle
- Complete blood count (hemoglobin, hematocrit)Confirm no unexpected erythropoiesis stimulation. Should remain stable — any significant Hb increase warrants discontinuation and investigation.Check: At end of 28-day cycle
- Metabolic markers (HbA1c, fasting glucose, lipids) — for diabetic usersPhase 2 trial data showed HbA1c and lipid improvements continuing to day 56 (beyond the 28-day treatment). Track these in diabetic users for both safety and efficacy signals.Check: At 4 weeks and 8 weeks post-treatment start
Critical Warning Signs
- Significant elevation in hemoglobin or hematocrit (polycythemia signs)Discontinue immediately and seek medical evaluation. While theoretically not expected given ARA-290's mechanism, any unexpected erythropoiesis response must be taken seriously given EPO lineage.Urgency: Within 24-48 hours
- Severe allergic reaction — hives, swelling, anaphylaxisStop immediately. Seek emergency care. Document lot number.Urgency: IMMEDIATE
- Worsening neuropathic symptoms beyond 2 weeks of treatmentReassess diagnosis. Consider consulting a neurologist. Discontinue if no improvement by end of 28-day course.Urgency: Within 1 week if persistent
Featured in Stacking Protocols
Community-researched combinations involving this compound
BPC-157
Nerve and Tissue Repair StackComprehensive tissue repair — vascular/neural repair (ARA-290) + structural regeneration (BPC-157)
ARA-290 targets IRR-mediated neuroinflammation suppression and nerve fiber regeneration. BPC-157 promotes vascular repair, growth factor upregulation, and structural tissue healing. Together they address tissue damage from complementary directions — ARA-290 from the neuroimmune/anti-inflammatory angle, BPC-157 from the structural/angiogenic angle.
ARA-290 4 mg sub-Q daily (28-day course) + BPC-157 250–500 mcg sub-Q daily. Separate injections, rotate sites.
TB-500 (Thymosin Beta-4)
TB-500 (Thymosin Beta-4) Synergy StackNerve and muscle repair — actin regulation and anti-inflammatory (TB-500) + IRR-mediated neuroregeneration (ARA-290)
TB-500 promotes cell migration, actin polymerization, and systemic tissue repair with notable neuroprotective effects. ARA-290 provides specific nerve fiber regeneration and neuroinflammation control. Both peptides act on repair pathways; combination addresses neuropathy from multiple mechanistic angles.
ARA-290 4 mg sub-Q daily + TB-500 2–5 mg sub-Q once or twice weekly. Both during a 4-week course.
Low Dose Naltrexone (LDN)
Low Dose Naltrexone (LDN) Synergy StackNeuroimmune modulation — microglial modulation (LDN) + IRR activation (ARA-290)
LDN modulates TLR4 and microglial activity to reduce central neuroinflammation. ARA-290 addresses peripheral nerve fiber neuroinflammation via IRR. Together they may provide more comprehensive neuroimmune modulation for conditions like small fiber neuropathy, long COVID, and fibromyalgia.
LDN 1.5–4.5 mg oral daily (physician-guided) + ARA-290 4 mg sub-Q daily for 28-day course.
Alpha-Lipoic Acid (ALA)
Alpha-Lipoic Acid (ALA) Synergy StackAntioxidant support for peripheral nerve health alongside ARA-290 nerve repair
ALA is one of the few supplements with clinical evidence in diabetic neuropathy (IV and oral forms studied). It provides antioxidant protection to peripheral nerves while ARA-290 drives active nerve regeneration via IRR. Additive protective effect on the oxidative component of nerve damage.
ARA-290 4 mg sub-Q daily + Alpha-Lipoic Acid 600 mg oral daily. Both during the 28-day ARA-290 course.