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

TB-500vsTriptorelin

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

APhase 2HUMAN-REVIEWED8/46 cited
BFDA-ApprovedHUMAN-REVIEWED16/64 cited
TB-500
Thymosin β4 fragment · Healing
2 mgPer doseGoldstein 2012
Phase 2Evidence levelGoldstein 2012
~2 hrHalf-life
SQ or IM · Multiple sites · 2–3×/week
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
TB-500
Triptorelin
Primary target
G-actin (sequestering) + cell-surface integrinsGoldstein 2012
Pituitary GnRH receptorsUnknown 2012
Pathway
Actin remodelling → cell migration; integrin-linked signaling → angiogenesis; anti-inflammatory cytokine modulationGoldstein 2012Malinda 1999
GnRH receptor agonism → initial flare (LH/FSH spike) → receptor desensitization → sustained LH/FSH suppression
Downstream effect
Accelerated wound healing, endothelial migration, hair follicle regeneration, cardiac repair (preclinical)Goldstein 2012
Castration-level suppression of testosterone (men) and estrogen (women) within 2–4 weeks post-flare
Feedback intact?
Endogenous protein at baseline; supplementation amplifies
No — bypasses physiological pulsatility; continuous agonism produces paradoxical suppression
Origin
17-AA active fragment of endogenous 43-AA thymosin β4 (TMSB4X gene)Goldstein 2012
Synthetic decapeptide analogue of native GnRH with amino acid substitutions for enhanced receptor affinity and stability
Antibody development

02Dosage Protocols

Parameter
TB-500
Triptorelin
Standard dose
2 mg per injectionGoldstein 2012
Anecdotal community range; clinical Phase 2 trials used 70–840 mcg/kg IV.
Frequency
2× per week (loading); then 1× per week (maintenance)
Every 1, 3, or 6 months per formulation
Lower / starter dose
1 mg per injection
Evidence basis
Animal-strong + Phase 2 dermal/ocular trialsGoldstein 2012
Multiple Phase 3 RCTs · FDA-approved 1999
Duration
4–8 weeks loading; longer maintenance for chronic injury
Reconstitution
Bacteriostatic water, 1–2 mL per 5 mg vial
Timing
Evening or pre-rest preferred (anecdotal)
Half-life
~2 hours (estimated; tissue uptake longer)
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

04Side Effects & Safety

Parameter
TB-500
Triptorelin
Injection site reaction
Mild erythema, transient pain
GI symptoms
Rare nausea (anecdotal)
Cancer risk
Theoretical via angiogenesis pathway
Lethargy / fatigue
Reported anecdotally during loading phase
Antibody formation
No data (no long-term human trials)
Pregnancy / OB
Avoid
Long-term safety
Unknown beyond Phase 2
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
TB-500
  • ·Active malignancy (theoretical angiogenesis concern)
  • ·Pregnancy / breastfeeding
Triptorelin
  • ·Hypersensitivity to triptorelin, GnRH, or GnRH agonist analogues
  • ·Pregnancy (Category X)
Relative Contraindications
TB-500
  • ·Cancer history
  • ·Concurrent VEGF inhibitor therapy
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
TB-500
Triptorelin
1. Reconstitution
Add 1–2 mL bacteriostatic water to 5 mg vial → 2.5–5 mg/mL. Roll gently.
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
SQ near injury site (preferred), or systemic SQ (abdomen). Rotate sites.
Intramuscular — gluteal or deltoid muscle. Use 21–23G needle. Aspirate to confirm non-vascular placement. Rotate sites with repeat injections.
3. Timing
Evening or pre-sleep is most common anecdotal timing.
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. Storage
Lyophilised: room temp, light-protected. Reconstituted: refrigerate, ≤30 days.
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. Needle
27–31G, 4–8 mm insulin syringe.
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

TB-500
+ BPC-157
Strong
View BPC-157

TB-500 and BPC-157 cover complementary halves of tissue repair: BPC-157 upregulates VEGFR2-driven angiogenesis and fibroblast outgrowth; TB-500 sequesters G-actin to enable endothelial / epithelial migration. The anecdotal canonical "healing stack" — pairs especially well for tendon and ligament injuries.

TB-500
2 mg SQ · 2× per week
BPC-157
250–500 mcg SQ · daily
Primary benefit
Combined angiogenesis + cell migration for tendon/ligament/muscle repair
Triptorelin
— no documented stacks