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Specimen Atlas of Research Peptides81 plates · MIT
Side-by-side · Research reference

ARA 290vsTriptorelin

Side-by-side comparison across mechanism, dosage, evidence, side effects, administration, and stack synergies. Citations on every claim where available.

APhase 2HUMAN-REVIEWED17/59 cited
BFDA-ApprovedHUMAN-REVIEWED16/64 cited
ARA 290
EPO-Derived Peptide · Innate Repair Receptor Agonist
28 daysPhase 2 durationCulver 2017
Non-erythropoieticSafety profileBrines 2015Liu 2014
Triptorelin
GnRH Agonist · FDA-Approved
3.75–22.5 mgDepot dose rangeYee 2025Chen 2024
<50 ng/dLTestosterone target
1–6 monthsDepot durationYee 2025Chen 2024
IM · Depot Injection · Monthly to 6-MonthlyYee 2025

01Mechanism of Action

Parameter
ARA 290
Triptorelin
Primary target
Innate repair receptor (EPO receptor / CD131 heterodimer)
Pituitary GnRH receptorsUnknown 2012
Pathway
EPO/CD131 → JAK2 activation → PI3K/AKT, MAPK signaling → anti-inflammatory, anti-apoptotic cascades
GnRH receptor agonism → initial flare (LH/FSH spike) → receptor desensitization → sustained LH/FSH suppression
Downstream effect
Tissue protection, nerve fiber regeneration, suppression of inflammatory macrophage activation, altered T-cell differentiation (↑Treg, ↑Th2, ↓Th1)Liu 2014Culver 2017
Castration-level suppression of testosterone (men) and estrogen (women) within 2–4 weeks post-flare
Feedback intact?
N/A — does not interact with hematopoietic EPO receptorLiu 2014
No — bypasses physiological pulsatility; continuous agonism produces paradoxical suppression
Origin
11-amino-acid sequence from EPO helix B, engineered to eliminate hematopoietic activity while retaining tissue-protective properties
Synthetic decapeptide analogue of native GnRH with amino acid substitutions for enhanced receptor affinity and stability
Antibody development
Not reported in clinical trials

02Dosage Protocols

Parameter
ARA 290
Triptorelin
Standard dose (Phase 2)
4 mg / dayBrines 2015Culver 2017
Sarcoidosis SFN and diabetic neuropathy trials.
Frequency
Once daily
Self-administered subcutaneously.
Every 1, 3, or 6 months per formulation
Duration
28 days (Phase 2)Culver 2017
Corneal nerve improvements observed by day 28.
Evidence basis
Phase 2 RCTsCulver 2017Brines 2015
64-subject sarcoidosis trial, type 2 diabetes trial.
Multiple Phase 3 RCTs · FDA-approved 1999
Route
SubcutaneousBrines 2015
Timing
Any time of day
No circadian dependence reported.
1-month depot
3.75 mg IM
Most common formulation for prostate cancer.
3-month depot
11.25 mg IMYee 2025
Reduced injection frequency.
6-month depot
22.5 mg IMYee 2025Chen 2024
Long-acting formulation; improved adherence in real-world use.Yee 2025
Administration route
Intramuscular (IM) — gluteal or deltoid
Indication: Prostate cancer
Advanced (metastatic or locally advanced)
Androgen deprivation therapy (ADT) backbone.
Indication: Endometriosis
3.75 mg monthly
FDA-approved; typically 6-month course.
Indication: Central precocious puberty
Pediatric use (≥2 years)Jia 2025
Weight-based dosing per FDA label.
Duration (prostate cancer)
Continuous or intermittent ADT protocolsPreston 2024
Intermittent ADT may reduce side effects; cardiovascular risk similar to continuous.
Monitoring
Serum testosterone, PSA (prostate cancer), bone density, lipids, glucose

03Metabolic / Fat Loss Evidence

Parameter
ARA 290
Triptorelin
Primary effect
Improved metabolic control (HbA1c, fasting glucose)Brines 2015
Secondary to neuropathy treatment; direct lipolytic effects not established.
HbA1c
Significant reduction vs placebo
Observed in type 2 diabetes + neuropathy trial.
Fasting glucose
Improved in ARA 290 group
Body composition
Not directly quantified
Fat loss not a primary endpoint; metabolic improvements may reflect insulin sensitivity.

04Side Effects & Safety

Parameter
ARA 290
Triptorelin
Injection site reaction
Mild, transient
Hematopoiesis
None — non-erythropoietic
Distinguishes ARA 290 from native EPO.
Cardiovascular
No thrombotic events or hypertension reported
Immunogenicity
No antibody formation reported
Tolerability
Well-tolerated in Phase 2 trialsCulver 2017Brines 2015
Initial flare symptoms
Bone pain, urinary obstruction, spinal cord compression (first 2 weeks)
Antiandrogen co-treatment (bicalutamide) mitigates flare in metastatic disease.
Cardiovascular events
MI, stroke, arrhythmia — GnRH agonists show higher CV risk vs antagonists in meta-analysesPatel 2025Preston 2024
Hot flashes
Very common (>60%); vasomotor instability
Bone loss / Osteoporosis
Accelerated bone mineral density decline; fracture risk ↑Friedrich 2025
Baseline DEXA scan recommended; bisphosphonates or denosumab may be indicated.
Metabolic syndrome
Weight gain, insulin resistance, dyslipidemia, diabetes risk
Sexual dysfunction
Erectile dysfunction, loss of libido (expected pharmacological effect)Jia 2025
Injection site reactions
Pain, erythema, sterile abscess (rare with depot formulations)
Gynecomastia / Breast tenderness
Common (10–20%); peripheral aromatization of residual androgens
Fatigue / Mood changes
Anemia, depression, cognitive changes reported in long-term ADT
Hepatotoxicity
Transient transaminase elevations; clinically apparent liver injury rare
Racial differences (ADT)
Black veterans show higher CV event rates vs White veterans on GnRH agonists
Absolute Contraindications
ARA 290
  • ·Hypersensitivity to ARA 290
Triptorelin
  • ·Hypersensitivity to triptorelin, GnRH, or GnRH agonist analogues
  • ·Pregnancy (Category X)
Relative Contraindications
ARA 290
  • ·Active malignancy (theoretical EPO-axis concern; not observed in trials)
Triptorelin
  • ·Active cardiovascular disease — consider GnRH antagonist alternative
  • ·Metastatic vertebral disease with spinal cord compression risk (flare hazard)
  • ·Severe urinary obstruction — may worsen during flare
  • ·Osteoporosis or high fracture risk (requires bone-protective therapy)

05Administration Protocol

Parameter
ARA 290
Triptorelin
1. Preparation
Reconstitute lyophilised powder per manufacturer instructions. Use sterile technique.
Choose 1-month (3.75 mg), 3-month (11.25 mg), or 6-month (22.5 mg) depot based on adherence needs and clinical context. 6-month formulation shows improved real-world adherence in Asia-Pacific cohorts.
2. Injection site
Subcutaneous — abdomen, thigh, or upper arm. Rotate sites to avoid lipohypertrophy.
Intramuscular — gluteal or deltoid muscle. Use 21–23G needle. Aspirate to confirm non-vascular placement. Rotate sites with repeat injections.
3. Timing
Once daily, any time of day. Self-administered in Phase 2 trials.Brines 2015
For metastatic prostate cancer: co-administer antiandrogen (e.g., bicalutamide 50 mg daily) starting 1 week before first injection and continuing 2–4 weeks to prevent tumor flare.
4. Dosing
4 mg daily for 28 days (Phase 2 protocol). Duration for chronic use not established.Culver 2017
Baseline: testosterone, PSA, bone density (DEXA), lipids, glucose. Follow-up: testosterone at 4 weeks (confirm <50 ng/dL castration), PSA monthly × 3, then quarterly. Annual DEXA for bone loss.
5. Storage
Lyophilised: store at controlled room temperature. Reconstituted: refrigerate, use within specified timeframe.
Store vials at room temperature (20–25 °C), protect from light. Do not freeze. Reconstituted suspension should be used immediately.
6. Intermittent ADT protocol (optional)
Some protocols use on-treatment periods (9–12 months) alternating with off-treatment intervals until PSA rises. Cardiovascular risk appears similar to continuous ADT.

06Stack Synergy

ARA 290
+ BPC-157
Moderate
View BPC-157

ARA 290 targets the innate repair receptor (EPO/CD131) for nerve regeneration and anti-inflammatory signaling, while BPC-157 promotes angiogenesis and tissue repair through distinct mechanisms (likely involving VEGF, growth hormone receptor pathways). Combined, they may address both neuroinflammation and structural tissue repair in neuropathy or injury models. No direct clinical data; mechanistic overlap in tissue protection.

ARA 290
4 mg SQ · daily
BPC-157
250–500 mcg SQ · daily
Frequency
Once daily, same or separate injections
Primary benefit
Nerve regeneration, pain reduction, tissue healing
Triptorelin
— no documented stacks