Peptide Comparison
Relaxin-2 (Serelaxin)vsTB-500
Recombinant human relaxin-2 studied for acute heart failure recovery and cardiovascular support
A powerful fragment of thymosin beta-4 that acts like your body's repair signal—speeding up healing of muscles, tendons, and tissues by promoting cell migration and new blood vessel growth right where you need it most.
At a Glance
Quick
comparison
Dose Range
Relaxin-2 (Serelaxin)
1–10 mcg
TB-500
2–5 mg
Frequency
Relaxin-2 (Serelaxin)
Once daily
TB-500
Twice weekly
Administration
Relaxin-2 (Serelaxin)
Intravenous (IV) infusion
TB-500
Subcutaneous injection
Cycle Length
Relaxin-2 (Serelaxin)
8-12 weeks
TB-500
4-6 weeks
Onset Speed
Relaxin-2 (Serelaxin)
Moderate (1-2 weeks)
TB-500
Moderate (1-2 weeks)
Evidence Level
Relaxin-2 (Serelaxin)
Limited human trials
TB-500
Moderate human trials (Phase 1-2)
Efficacy
Benefit
ratings
Cardiovascular Function
Heart Failure Support
Acute Medical Management
Healing Speed
Tissue Repair
Anti-Scarring
Technical Data
Compound
specifications
Relaxin-2 (Serelaxin)
Molecular Formula
C256H408N74O74S8
Molecular Weight
5,963 Da (Daltons)
Half-Life
Varies by route of administration
Bioavailability
Varies by route of administration
CAS Number
See PubChem for identifiers
TB-500
Molecular Formula
C38H68N10O14
Molecular Weight
889.01 g/mol
Half-Life
2-3 days (systemic)
Bioavailability
High via subcutaneous injection (~100%)
CAS Number
885340-08-9
Protocols
Dosing
tiers
Relaxin-2 (Serelaxin)
TB-500
Applications
Best
suited for
Relaxin-2 (Serelaxin)
Acute heart failure symptom management
Relaxin-2 (Serelaxin) is particularly effective for individuals focused on acute heart failure symptom management. Research supports its use in this area.
Cardiovascular recovery and support
Relaxin-2 (Serelaxin) is particularly effective for individuals focused on cardiovascular recovery and support. Research supports its use in this area.
Hospital-based therapeutic interventions
Relaxin-2 (Serelaxin) is particularly effective for individuals focused on hospital-based therapeutic interventions. Research supports its use in this area.
TB-500
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
Side
effects
Relaxin-2 (Serelaxin)
Common
- Hypotension (low blood pressure) - most common
- Tachycardia (increased heart rate)
- Headache
- Nausea
- Dizziness
- Peripheral edema (swelling)
- Increased creatinine levels
- Hyperkalemia (high potassium)
- Syncope (fainting)
- Atrial fibrillation
- Blood pressure checks every 2-4 hours during infusion
- Kidney function (creatinine and eGFR)
- Electrolytes, particularly potassium
- Heart rate and cardiac rhythm
- Urine output
Serious
- Severe cardiovascular events
TB-500
Common
- Injection site redness
- Mild fatigue or lethargy
- Mild headache
- Slight flushing
Uncommon
- Head rush or lightheadedness
- Temporary nausea
Serious
- Allergic reaction
Research Status
Safety
& evidence
Relaxin-2 (Serelaxin)
Evidence Level
Limited human trials
FDA Status
Research compound
Safety Overview
Serelaxin (recombinant relaxin-2) completed Phase III heart failure trials with favorable safety profile and cardiovascular benefit signals. Hypotension occurs in 20-25% of subjects requiring hemodynamic monitoring; no serious adverse events directly attributable to serelaxin beyond expected vasodilatory effects. Flushing and headaches mild and transient. No serious immunogenicity despite being recombinant human peptide; repeat dosing shows consistent response.
Contraindications
- xSevere hypotension or hemodynamic instability
- xPregnancy (despite relaxin's natural role)
- xAcute kidney injury or severe renal dysfunction
- xRecent myocardial infarction (within 7 days)
- xUncontrolled arrhythmias
TB-500
Evidence Level
Moderate human trials (Phase 1-2)
FDA Status
Research compound
Safety Overview
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.
Contraindications
- 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 is
right for you?
Choose Relaxin-2 (Serelaxin) if...
- Acute heart failure symptom management
- Cardiovascular recovery and support
- Hospital-based therapeutic interventions
Choose TB-500 if...
- Accelerating injury recovery
- Tendon and ligament healing
- Reducing chronic inflammation
- Post-surgical recovery support