At a Glance
Quickcomparison
Dose Range
Thymosin Beta-4
2–5 mg
TB-500
Frequency
Twice weekly
Administration
Subcutaneous injection
Cycle Length
8-12 weeks
4-6 weeks
Onset Speed
Moderate (1-2 weeks)
Evidence Level
Moderate human trials (Phase 1-2)
Efficacy
Benefitratings
Wound Healing
Inflammation Reduction
Tissue Regeneration
Healing Speed
Tissue Repair
Anti-Scarring
Technical Data
Compoundspecifications
Molecular Formula
C212H350N56O78S
Molecular Weight
4963
Half-Life
Dose-dependent (increases with higher doses)
Bioavailability
100% (subcutaneous and intravenous)
CAS Number
77591-33-4
C38H68N10O14
889.01 g/mol
2-3 days (systemic)
High via subcutaneous injection (~100%)
885340-08-9
Protocols
Dosingtiers
standard
2-5 mg (community injectable practice for 'TB-500')
Once or twice weekly
4-6 week loading phase, then weekly maintenance
Documented community/research-practice injectable dosing for tissue repair; thymosin beta-4 has ~100% bioavailability by the subcutaneous route [1]. Not an FDA-approved use.
0.1% (1 mg/mL) RGN-259 solution, 1 drop
Several times daily (e.g. up to 5x/day)
4 weeks
0.1% RGN-259 ophthalmic solution used in phase III neurotrophic keratopathy and dry-eye trials, applied as eye drops several times daily for ~4 weeks [5].
advanced
450-1200 mg
IV push daily for the first 3 days, then weekly
Total of 7 doses over ~5 weeks
Doses studied in the RGN-352 acute myocardial infarction clinical program, given IV after PCI [6].
starting
2-2.5 mg
Loading phase, 4-6 weeks
Research peptide with no human trials of the fragment; loading doses used in practice [6].
Once weekly
Maintenance after loading
Maintenance dose used in practice following the loading phase [6].
Applications
Bestsuited for
Post-Surgery Recovery
Accelerates healing of surgical wounds and reduces post-operative inflammation and scarring
Chronic Wound Management
Helps pressure ulcers, venous stasis ulcers, and other slow-healing wounds progress faster
Supports repair of damaged tissues from injury, burns, or degenerative conditions
Athletes Recovering from Muscle Injuries
If you've pulled a hamstring, strained your back, or torn a muscle, TB-500 helps accelerate the healing process by promoting cell migration to the injury site and supporting new blood vessel growth. It's especially useful for injuries that just won't seem to fully heal.
Tendon and Ligament Problems
Tendons and ligaments are notoriously slow healers because they have poor blood supply. TB-500 promotes angiogenesis (new blood vessel formation) and helps repair these stubborn connective tissue injuries—think Achilles tendonitis, tennis elbow, or rotator cuff issues.
Post-Surgical Recovery
After surgery, your body needs to repair a lot of tissue quickly. TB-500 supports wound healing, reduces inflammation, and may help minimize scar tissue formation. Some protocols use it alongside traditional recovery to potentially speed up the healing timeline.
Chronic Inflammation and Slow Healers
Some people just heal slowly—whether due to age, diabetes, or other factors. TB-500 helps regulate the inflammatory response and promotes the cellular processes needed for tissue repair. It essentially tells your body to focus healing resources where they're needed most.
Safety Profile
Sideeffects
Common
Injection site redness
Injection site swelling
Uncommon
Temporary mild headache
Mild bruising at injection site
Transient fatigue
Serious
Allergic reaction
Mild fatigue or lethargy
Mild headache
Slight flushing
Head rush or lightheadedness
Temporary nausea
Research Status
Safety& evidence
FDA Status
Research compound
Safety Overview
Thymosin Beta-4 is a naturally occurring peptide found in all cells and body fluids in the human body. Clinical trials have demonstrated excellent safety even at very high doses. IV studies showed doses up to 1260 mg were well tolerated with no serious adverse events.
Contraindications
xActive systemic infections
xSevere immunosuppression
xHypersensitivity to thymosin or any component
xPregnancy (insufficient safety data)
TB-500 has shown a good safety profile across preclinical studies and limited human research. It's a fragment of thymosin beta-4, a naturally occurring protein in your body involved in healing. Most side effects are mild and transient, primarily injection site reactions. However, large-scale clinical trials are still needed to fully establish its safety profile in humans.
xPregnancy or planning to become pregnant
xCurrently breastfeeding
xActive cancer or history of cancer
xKnown allergy to peptide components
xChildren and adolescents
Decision Guide
Which isright for you?
Choose Thymosin Beta-4 if...
Recovering from injuries or surgery
Improving wound healing speed
Reducing inflammation
Minimizing scar formation
Choose TB-500 if...
Accelerating injury recovery
Tendon and ligament healing
Reducing chronic inflammation
Post-surgical recovery support