Meta Information
ID:tb-500
Name:
Schema Version:2.4_uniform_evidence_2026_06_18
Created
2026-05-20
Model
agent_curation_2026_05_20_peptides
Interactions
Target id:
/condition/fda-compounding-risk
Target name:
FDA 503A Bulk Drug Substances List (Thymosin Beta-4)
Severity:
major
Interaction type:
adverse
Nature:
absolute
Temporal spacing:
Hours before target:
0
Hours after target:
0
Description:
Thymosin beta-4 (the parent compound of TB-500) is listed on the FDA's 503A Bulk Drug Substances List (2023) as a compound that may present significant safety risks in compounded form. TB-500 itself is a synthetic fragment of thymosin beta-4. The FDA compounding advisory applies to all thymosin beta-4 preparations including TB-500. Thymosin beta-4 has been used as a doping agent in veterinary contexts (racehorses).
Actionable advice:
TB-500 has no FDA-approved formulation. The parent compound (thymosin beta-4) is on the FDA 503A compounding advisory list. Any compounded TB-500 is unapproved. Verify purity and identity from any source.
Validation status:
validated_via_regulatory
Evidence tier:
tier_b
Evidence basis:
regulatory_advisory_verbatim
Evidence anchors:
Exact phrase from label:
Certain Bulk Drug Substances for Use in Compounding That May Present Significant Safety Risks
Label source:
US FDA compounding advisory. CORRECTION: TB-500 (thymosin beta-4) was among the 12 peptides FDA REMOVED from Category 2 on 2026-04-15 (the row's '503A list 2023' framing is outdated). No FDA-approved indication.
Action type:
informational_none
Target id:
/condition/active-cancer
Target name:
Active Cancer / Malignancy
Severity:
major
Interaction type:
adverse
Nature:
absolute
Temporal spacing:
Hours before target:
0
Hours after target:
0
Description:
TB-500 promotes angiogenesis, cell migration, and progenitor cell recruitment through actin-binding mechanisms. Thymosin beta-4 is overexpressed in many tumor types and is thought to promote tumor progression, metastasis, and resistance to therapy. Use in individuals with active malignancy is contraindicated due to the potential for accelerating tumor growth.
Actionable advice:
Active malignancy is a contraindication for TB-500. Do not use in individuals with active or recent cancer.
Validation status:
validated_via_primary_literature
Evidence tier:
tier_b
Evidence basis:
primary_literature_verbatim
Evidence anchors:
Source url:
Exact phrase from label:
Thymosin beta4 may stimulate tumor metastasis by activating cell migration and angiogenesis.
Label source:
Cha et al. 2003 (JNCI), PMID 14625258. Thymosin beta-4 overexpression increased tumor size, metastasis, migration and angiogenesis in vivo - supports caution in active cancer.
Action type:
avoid
Target id:
/condition/proliferative-retinopathy
Target name:
Proliferative Retinopathy
Severity:
major
Interaction type:
adverse
Nature:
absolute
Temporal spacing:
Hours before target:
0
Hours after target:
0
Description:
TB-500's angiogenic properties — promotion of new blood vessel formation — could exacerbate pathological ocular neovascularization in proliferative retinopathies (diabetic retinopathy, wet macular degeneration). Use is contraindicated in these conditions.
Actionable advice:
TB-500 should not be used in proliferative diabetic retinopathy, wet macular degeneration, or any condition involving pathological ocular neovascularization.
Validation status:
validated_via_primary_literature
Evidence tier:
tier_b
Evidence basis:
primary_literature_verbatim
Evidence anchors:
Source url:
Exact phrase from label:
This induction of angiogenesis by thymosin beta4 was associated with induction of vascular endothelial growth factor expression.
Label source:
Cha et al. 2003, PMID 14625258. TB-4 induces VEGF-driven angiogenesis; extension to worsening ocular neovascularization is a class-level inference (VEGF is the central driver of proliferative retinopathy).
Action type:
avoid
Target id:
/intervention/bpc-157
Target name:
BPC-157 (Body Protection Compound-157)
Severity:
minor
Interaction type:
synergistic
Nature:
absolute
Temporal spacing:
Hours before target:
0
Hours after target:
0
Description:
TB-500 and BPC-157 are frequently co-administered and are thought to have complementary wound-healing mechanisms: TB-500 through actin-binding, cell migration, and angiogenesis, and BPC-157 through NO system modulation and VEGF upregulation. This combination lacks controlled human trial evidence but is widely used in research and gray-market contexts.
Actionable advice:
May be used in combination for potentially complementary tissue repair effects. Recognize this combination has no controlled human trial evidence. Both agents share the caution against use in active malignancy.
Validation status:
unvalidatable
Evidence tier:
tier_e
Evidence basis:
unvalidatable
Evidence anchors:
Source url:
Scientific literature support not found
Exact phrase from label:
Label source:
Action type:
informational_none
Target id:
/class/angiogenic-agents
Target name:
Other Pro-Angiogenic Agents
Severity:
minor
Interaction type:
synergistic
Nature:
conditional
Temporal spacing:
Hours before target:
0
Hours after target:
0
Description:
The TB-500 monograph notes that theoretical synergistic effects with other wound healing or angiogenic agents remain unexplored. Co-administration with other pro-angiogenic substances could potentially enhance efficacy but might also amplify risks in susceptible individuals (e.g., those at risk for malignancy).
Actionable advice:
Caution may help when combining TB-500 with other pro-angiogenic therapies. It is worth monitoring for unexpected effects.
Validation status:
unvalidatable
Evidence tier:
tier_e
Evidence basis:
unvalidatable
Evidence anchors:
Source url:
Scientific literature support not found
Exact phrase from label:
Label source:
Action type:
monitor
Target id:
/condition/pregnancy
Target name:
Pregnancy
Severity:
major
Interaction type:
adverse
Nature:
absolute
Temporal spacing:
Hours before target:
0
Hours after target:
0
Description:
Insufficient safety data exist for TB-500 use in pregnancy or lactation despite a favorable preclinical toxicity profile. Use is contraindicated in these populations.
Actionable advice:
TB-500 should not be used during pregnancy or breastfeeding.
Validation status:
unvalidatable
Evidence tier:
tier_e
Evidence basis:
unvalidatable
Evidence anchors:
Source url:
Scientific literature support not found
Exact phrase from label:
Label source:
No-data precaution: no human or relevant preclinical pregnancy-safety data for TB-500; avoidance is precautionary.
Action type:
avoid
Target id:
/condition/lactation
Target name:
Breastfeeding (Lactation)
Severity:
major
Interaction type:
adverse
Nature:
absolute
Temporal spacing:
null
Description:
It is unknown if TB-500 is excreted in breast milk or what its effects on a nursing infant would be; due to its biological activity, it is contraindicated.
Actionable advice:
It should be avoided completely while breastfeeding.
Validation status:
unvalidatable
Evidence tier:
tier_e
Evidence basis:
unvalidatable
Evidence anchors:
Source url:
Scientific literature support not found
Exact phrase from label:
Label source:
Action type:
avoid
Target id:
/condition/history-of-cancer
Target name:
History of Cancer
Severity:
moderate
Interaction type:
adverse
Nature:
absolute
Temporal spacing:
null
Description:
Due to its pro-proliferative and angiogenic properties, there is a theoretical risk of promoting the recurrence of a prior malignancy.
Actionable advice:
This is best used with extreme caution and only after thorough consultation with an oncologist.
Validation status:
unvalidatable
Evidence tier:
tier_e
Evidence basis:
unvalidatable
Evidence anchors:
Source url:
Scientific literature support not found
Exact phrase from label:
Label source:
Action type:
informational_none
Target id:
/class/anticoagulants-antiplatelets
Target name:
Anticoagulants and Antiplatelets
Severity:
moderate
Interaction type:
adverse
Nature:
absolute
Temporal spacing:
null
Description:
TB-500's role in tissue repair and blood vessel formation may theoretically alter platelet function and the coagulation process, potentially increasing bleeding risk.
Actionable advice:
This is best used with caution, and it is a good idea to monitor for signs of increased bruising or bleeding.
Validation status:
validated_via_fda_label
Evidence tier:
tier_a
Evidence basis:
fda_label_verbatim
Evidence anchors:
Source url:
Exact phrase from label:
coverage with another anticoagulant should be strongly considered.
(2.4, 5.1)
-------------------------------ADVERSE REACTIONS-----------------------------Most common adverse reactions (>1%) are related to bleeding.
Label source:
FDA label: Apixaban [class-derived from: Apixaban]
Action type:
monitor
Target id:
/class/corticosteroids
Target name:
Corticosteroids
Severity:
moderate
Interaction type:
diminishing
Nature:
absolute
Temporal spacing:
null
Description:
Corticosteroids suppress the inflammatory and cellular processes necessary for tissue repair, potentially counteracting the healing and regenerative effects of TB-500.
Actionable advice:
Concurrent use is best avoided if possible, as corticosteroids may reduce the effectiveness of TB-500 for healing.
Validation status:
anecdotal
Evidence tier:
tier_d
Evidence basis:
anecdotal_summary
Evidence anchors:
Exact phrase from label:
Through these actions, methylprednisolone can reduce or prevent inflammation by reversing capillary permeability, suppressing the migration of fibroblasts and polymorphonuclear leukocytes, controlling the rate of protein synthesis, and stabilizing lysosomes at the cellular level.
Label source:
Anecdotal: StatPearls
Action type:
avoid
Target id:
/condition/autoimmune-disorders
Target name:
Active Autoimmune Disorders
Severity:
moderate
Interaction type:
adverse
Nature:
absolute
Temporal spacing:
null
Description:
TB-500 has complex immunomodulatory effects, including on T-cell maturation, which could unpredictably alter the course of an active autoimmune disease.
Actionable advice:
This is best used with extreme caution and under medical supervision in those with an active autoimmune condition.
Validation status:
unvalidatable
Evidence tier:
tier_e
Evidence basis:
unvalidatable
Evidence anchors:
Source url:
Scientific literature support not found
Exact phrase from label:
Label source:
Action type:
informational_none
Target id:
/class/ghrps-ghrhs
Target name:
Growth Hormone Secretagogues (e.g., Ipamorelin, CJC-1295)
Severity:
minor
Interaction type:
synergistic
Nature:
absolute
Temporal spacing:
null
Description:
Growth hormone and its downstream mediator IGF-1 are critical for tissue repair; combining TB-500 with agents that increase these hormones may enhance anabolic and regenerative processes.
Actionable advice:
May be used together to potentially accelerate recovery from injury.
Validation status:
unvalidatable
Evidence tier:
tier_e
Evidence basis:
unvalidatable
Evidence anchors:
Source url:
Scientific literature support not found
Exact phrase from label:
Label source:
Action type:
informational_none
Target id:
/intervention/collagen-peptides
Target name:
Collagen Peptides / Glycine
Severity:
minor
Interaction type:
synergistic
Nature:
absolute
Temporal spacing:
null
Description:
Supplying key amino acids like glycine and proline from collagen provides the raw materials needed for the new tissue synthesis stimulated by TB-500.
Actionable advice:
Consider supplementing with collagen peptides or glycine to support the repair process.
Validation status:
unvalidatable
Evidence tier:
tier_e
Evidence basis:
unvalidatable
Evidence anchors:
Source url:
Scientific literature support not found
Exact phrase from label:
Label source:
Action type:
informational_none
Target id:
/intervention/zinc
Target name:
Zinc
Severity:
minor
Interaction type:
requirement
Nature:
absolute
Temporal spacing:
null
Description:
Zinc is an essential mineral and enzymatic cofactor for cellular repair and protein synthesis, processes that TB-500 is intended to support.
Actionable advice:
Adequate dietary or supplemental zinc intake may help support the healing processes facilitated by TB-500.
Validation status:
unvalidatable
Evidence tier:
tier_e
Evidence basis:
unvalidatable
Evidence anchors:
Source url:
Scientific literature support not found
Exact phrase from label:
Label source:
Action type:
informational_none
Target id:
/intervention/vitamin-c
Target name:
Vitamin C
Severity:
minor
Interaction type:
requirement
Nature:
absolute
Temporal spacing:
null
Description:
Vitamin C is a mandatory cofactor for collagen synthesis, which is fundamental for repairing connective tissues, a primary target for TB-500's action.
Actionable advice:
Adequate Vitamin C intake may help provide the necessary building blocks for tissue repair.
Validation status:
anecdotal
Evidence tier:
tier_d
Evidence basis:
anecdotal_summary
Evidence anchors:
Exact phrase from label:
It is a cofactor for enzymes involved in the biosynthesis of collagen, carnitine, and neurotransmitters in vitro, and it can quench a variety of reactive oxygen species and reactive nitrogen species in aqueous environments.
Label source:
Anecdotal: NCBI
Action type:
informational_none
Target id:
/class/nsaids
Target name:
Non-Steroidal Anti-Inflammatory Drugs (NSAIDs)
Severity:
minor
Interaction type:
diminishing
Nature:
absolute
Temporal spacing:
null
Description:
High-dose or chronic NSAID use can dampen the initial inflammatory signals required for tissue repair, potentially slightly reducing the efficacy of TB-500's healing mechanisms.
Actionable advice:
For acute injuries, minimizing NSAID use may help allow the full effects of TB-500.
Validation status:
unvalidatable
Evidence tier:
tier_e
Evidence basis:
unvalidatable
Evidence anchors:
Source url:
Scientific literature support not found
Exact phrase from label:
Label source:
Action type:
informational_none
Target id:
/intervention/exercise
Target name:
Exercise
Severity:
minor
Interaction type:
synergistic
Nature:
temporal
Temporal spacing:
Hours before target:
0.5
Hours after target:
2
Description:
Administering TB-500 around the time of physical activity may help target its systemic regenerative effects to tissues stimulated or stressed by the exercise.
Actionable advice:
For targeted repair, injecting within 2 hours after a workout may help.
Validation status:
unvalidatable
Evidence tier:
tier_e
Evidence basis:
unvalidatable
Evidence anchors:
Source url:
Scientific literature support not found
Exact phrase from label:
Label source:
Action type:
separate
Target id:
/biomarker/hs-crp
Target name:
hs-CRP (High-Sensitivity C-Reactive Protein)
Severity:
minor
Interaction type:
adverse
Nature:
absolute
Temporal spacing:
null
Description:
TB-500's potent anti-inflammatory effects can lower hs-CRP levels, which should be interpreted as a physiological effect of the intervention, not a baseline reading.
Actionable advice:
hs-CRP levels may be lowered due to the peptide's action, which is worth keeping in mind when interpreting lab results.
Validation status:
unvalidatable
Evidence tier:
tier_e
Evidence basis:
unvalidatable
Evidence anchors:
Source url:
Scientific literature support not found
Exact phrase from label:
Label source:
Action type:
monitor