Peptide Comparison
ThymopoietinvsThymosin Alpha-1
Thymic hormone that supports T-cell development and immune function, with the active fragment thymopentin (TP-5) used in clinical research
Your immune system's master trainer—a naturally occurring thymus peptide that wakes up tired immune cells, helps your body fight infections, and keeps your defenses sharp as you age.
At a Glance
Quick
comparison
Dose Range
Thymopoietin
50–100 mg
Thymosin Alpha-1
1.6–3.2 mg
Frequency
Thymopoietin
Every other day
Thymosin Alpha-1
Twice weekly
Administration
Thymopoietin
Subcutaneous injection
Thymosin Alpha-1
Subcutaneous injection
Cycle Length
Thymopoietin
4-6 weeks
Thymosin Alpha-1
8-12 weeks
Onset Speed
Thymopoietin
Moderate (1-2 weeks)
Thymosin Alpha-1
Moderate (1-2 weeks)
Evidence Level
Thymopoietin
Limited human trials
Thymosin Alpha-1
Moderate human trials (Phase 1-2)
Efficacy
Benefit
ratings
Immune Cell Development
Post-Surgical Recovery
Cancer Immunotherapy Enhancement
Immune Activation
Infection Fighting
Immune Balance
Technical Data
Compound
specifications
Thymopoietin
Molecular Formula
C246H404N66O73
Molecular Weight
5454
Half-Life
Minutes to hours in plasma
Bioavailability
Moderate with subcutaneous injection
CAS Number
67632-30-6
Thymosin Alpha-1
Molecular Formula
C129H215N33O55
Molecular Weight
3108.32 g/mol
Half-Life
Approximately 2 hours
Bioavailability
High when injected subcutaneously (rapid absorption, peak at ~2 hours)
CAS Number
62304-98-7
Protocols
Dosing
tiers
Thymopoietin
Thymosin Alpha-1
Applications
Best
suited for
Thymopoietin
Cancer Treatment Support
Used alongside chemotherapy to maintain immune function and reduce treatment side effects while enhancing anti-tumor immunity
Post-Surgical Immune Recovery
Helps restore T-cell function and prevent immune depression following major surgery or serious medical stress
HIV-Related Immune Support
Combined with antiretroviral therapy to support T-cell populations and improve immune response
Thymosin Alpha-1
Chronic Hepatitis B or C Support
Thymosin Alpha-1 has its strongest clinical evidence here. Multiple trials show it helps clear viral loads and normalize liver enzymes, especially when combined with antiviral medications. It's approved in over 30 countries specifically for hepatitis treatment.
Cancer Treatment Support
When used alongside chemotherapy, Thymosin Alpha-1 may help maintain immune function that chemo tends to suppress. Research in lung cancer, melanoma, and liver cancer shows improved outcomes when added to standard treatments. It helps your immune system keep fighting even during tough treatments.
Age-Related Immune Decline
As you age, your thymus shrinks and produces less thymosin naturally—a process called immunosenescence. Supplementing with Thymosin Alpha-1 may help compensate, keeping your immune defenses more youthful and responsive. Think of it as replacing what your body makes less of over time.
Severe Infection Recovery
In sepsis and critical infections, Thymosin Alpha-1 has shown promise for reducing mortality by helping restore immune balance. It's particularly interesting because it modulates immunity rather than just boosting it—calming overreaction while enhancing pathogen-fighting ability.
Safety Profile
Side
effects
Thymopoietin
Common
- Injection site redness or swelling
- Mild fever
- Transient lymphocytosis
Uncommon
- Mild to moderate fatigue
- Temporary headaches
- Joint or muscle aches
Serious
- Neuromuscular weakness or myasthenia-like symptoms
- Severe allergic reaction (anaphylaxis)
- Autoimmune flare
Thymosin Alpha-1
Common
- Injection site reactions
- Mild fatigue
- Flu-like symptoms
Uncommon
- Mild fever
- Lymph node awareness
Serious
- Allergic reaction
Research Status
Safety
& evidence
Thymopoietin
Evidence Level
Limited human trials
FDA Status
Research compound
Safety Overview
Thymopoietin is a naturally-derived thymic hormone with a well-characterized mechanism but limited human safety data. Most clinical experience comes from thymopentin (TP-5), the active pentapeptide fragment. It is generally well-tolerated but has important safety considerations, particularly regarding neuromuscular effects.
Contraindications
- xMyasthenia gravis or other neuromuscular junction disorders
- xActive autoimmune diseases
- xPregnancy and breastfeeding
- xSevere allergic reactions to thymic proteins
Thymosin Alpha-1
Evidence Level
Moderate human trials (Phase 1-2)
FDA Status
FDA approved for other use
Safety Overview
Thymosin Alpha-1 has one of the most extensive safety records of any peptide, with decades of clinical use across multiple countries. Studies consistently report minimal side effects—mostly limited to mild injection site reactions. The 2-hour half-life means it doesn't accumulate in your system. It's been used safely in thousands of patients with hepatitis, cancer, and other serious conditions.
Contraindications
- xOrgan transplant recipients on immunosuppressants
- xActive autoimmune disease flares
- xKnown allergy to thymosin peptides
- xPregnancy or breastfeeding
- xChildren under 18 without medical supervision
Decision Guide
Which is
right for you?
Choose Thymopoietin if...
- Supporting immune function during cancer treatment
- Recovering immune function after surgery
- Managing HIV-related immune deficiencies
- Enhancing response to other immunotherapies
Choose Thymosin Alpha-1 if...
- Immune system strengthening
- Chronic infection support
- Cancer adjunct therapy
- Healthy aging immune support