TB-500 (thymosin beta-4): research profile
Last updated Oct 8, 2026 · research counts checked Oct 7, 2026
Identity
- Name
- TB-500 (thymosin beta-4)
- Also called
- TB-500; thymosin beta-4 fragment Ac-LKKTETQ; thymosin β4 (Tβ4)
- Sequence
- Ac-LKKTETQ (7 residues)
- Molecular formula
- C38H68N10O14
- Molecular weight
- 889.0 g/mol
- CAS number
- 885340-08-9
- Source
- PubChem CID 62707662 ↗ · full-length record: CID 45382195 ↗
"TB-500" is used both for the 7-residue fragment Ac-LKKTETQ (PubChem's TB-500 record, shown here) and, on many vendor COAs, for full-length thymosin beta-4 (43 residues, PubChem CID 45382195). Check which molecule the identity line on a lot's COA names.
Sequences are shown only where the formula calculated from the sequence matches PubChem's formula exactly; CAS numbers only where the PubChem record lists a single valid one.
Published research record
Counts of database records matching the compound's names, as of Oct 7, 2026. They describe how much has been published and in what kind of study, not what any study found.
| Record type | Count | Source |
|---|---|---|
| PubMed records (any study type) | 1156 | PubMed search ↗ |
| …indexed as animal studies, with no human tag | 399 | PubMed search ↗ |
| …indexed as clinical trials (in people) | 9 | PubMed search ↗ |
| …indexed as reviews | 134 | PubMed search ↗ |
| ClinicalTrials.gov registered studies | 18 | ClinicalTrials.gov search ↗ |
PubMed query: "thymosin beta-4"[tiab] OR "thymosin beta4"[tiab] OR "TB-500"[tiab] OR "TB500"[tiab]. ClinicalTrials.gov query: "thymosin beta-4" OR "TB-500". PubMed's study-type tags are added by indexers and lag new records, and keyword matches can include records that only mention the compound, so read these as rough counts.
Regulatory status
- FDA (compounding): FDA placed it in Category 2 of its bulk-drug-substances list (substances that may present significant safety risks in compounding). The nomination was later withdrawn, and it now appears on FDA's "nominated but withdrawn" list. (listed as "Thymosin beta-4, fragment (LKKTETQ), also known as TB-500") FDA source ↗
- Sport (WADA): WADA's Prohibited List names thymosin-β4 and its derivatives (e.g. TB-500) under S2. WADA Prohibited List ↗
- Research peptides from both vendors are sold for laboratory research use only, not for human or veterinary consumption. This summary isn't legal or regulatory advice.
Lab-tested TB-500 (thymosin beta-4) lots (27)
| Lot | Vendor · product | Report date | Lab | HPLC purity | Identity |
|---|---|---|---|---|---|
| 26VTBC164 | Paramount Peptides · Thymosin Beta 4 (TB500) (10mg) | Jul 8, 2026 | Accumark Labs | 99.12% | Conforms (Thymosin Beta 4) |
| TB10-12222025-J | Paramount Peptides · Thymosin Beta 4 (TB500) (10mg) | Jul 6, 2026 | Accumark Labs | 99.81% | Conforms (Thymosin Beta 4) |
| 26VTBC110 | Paramount Peptides · Thymosin Beta 4 (TB500) (20mg) | May 15, 2026 | Accumark Labs | 99.39% | Conforms (Thymosin Beta 4) |
| 26VTBL068 | Paramount Peptides · Thymosin Beta 4 (TB500) (20mg) | May 7, 2026 | Accumark Labs | 99.62% | Conforms (17-23 Fragment) |
| 26VTBLO68 | Paramount Peptides · Thymosin Beta 4 (TB500) (20mg) | Apr 17, 2026 | Janoshik | 99.46% | Not reported |
| TB45N030126 | Paramount Peptides · Thymosin Beta 4 (TB500) (5mg) | Apr 17, 2026 | Janoshik | 99.78% | Not reported |
| TB5-10-005 | Peptira · TB-500 Vial 10 mg | Apr 16, 2026 | Freedom Diagnostics | 99.25% | Confirmed (LC-MS) |
| TB410N121525 | Paramount Peptides · Thymosin Beta 4 (TB500) (10mg) | Jan 9, 2026 | Janoshik | 99.69% | Not reported |
| TB5-10-004 | Peptira · TB-500 Vial 10 mg | Dec 18, 2025 | Freedom Diagnostics | 99.30% | Mass identified as Thymosin Beta-4 (LC-MS) |
| TB92025 | Paramount Peptides · Thymosin Beta 4 (TB500) (5mg) | Dec 4, 2025 | Janoshik | 99.04% | Not reported |
| TB420N111825 | Paramount Peptides · Thymosin Beta 4 (TB500) (20mg) | Nov 28, 2025 | Janoshik | 99.55% | Not reported |
| TB410A110725 | Paramount Peptides · Thymosin Beta 4 (TB500) (10mg) | Nov 20, 2025 | Janoshik | 99.24% | Not reported |
| TB45A110725 | Paramount Peptides · Thymosin Beta 4 (TB500) (5mg) | Nov 20, 2025 | Janoshik | 99.02% | Not reported |
| TB45A110825 | Paramount Peptides · Thymosin Beta 4 (TB500) (5mg) | Nov 20, 2025 | Janoshik | 99.22% | Not reported |
| TB5-10-003 | Peptira · TB-500 Vial 10 mg | Nov 20, 2025 | Freedom Diagnostics | 99.44% | Mass identified as Thymosin Beta-4 (LC-MS) |
| TB5A103125 | Paramount Peptides · Thymosin Beta 4 (TB500) (5mg) | Nov 6, 2025 | Janoshik | 99.02% | Not reported |
| TB410N072425 | Paramount Peptides · Thymosin Beta 4 (TB500) (10mg) | Aug 19, 2025 | Janoshik | 99.59% | Not reported |
| TB5-1-002 | Peptira · TB-500 Vial 10 mg | Aug 13, 2025 | Janoshik | 99.94% | Not reported |
| TB4F10N062325 | Paramount Peptides · Thymosin Beta 4 (TB500) (10mg) | Jul 17, 2025 | Janoshik | 99.93% | Not reported |
| TB5-10-001 | Peptira · TB-500 Vial 10 mg | Jul 16, 2025 | Janoshik | 99.86% | Not reported |
| TB410N062025 | Paramount Peptides · Thymosin Beta 4 (TB500) (10mg) | Jun 29, 2025 | Janoshik | 99.64% | Not reported |
| TB410N061325 | Paramount Peptides · Thymosin Beta 4 (TB500) (10mg) | Jun 25, 2025 | Janoshik | 99.01% | Not reported |
| TB45A060225 | Paramount Peptides · Thymosin Beta 4 (TB500) (5mg) | Jun 10, 2025 | Janoshik | 99.07% | Not reported |
| TB410N053025 | Paramount Peptides · Thymosin Beta 4 (TB500) (10mg) | Jun 8, 2025 | Janoshik | 99.51% | Not reported |
| TB45C€20125 | Paramount Peptides · Thymosin Beta 4 (TB500) (5mg) | May 5, 2025 | Janoshik | 99.03% | Not reported |
| TB410N12162024 | Paramount Peptides · Thymosin Beta 4 (TB500) (10mg) | Jan 2, 2025 | Janoshik | 99.37% | Not reported |
| HTB4-0005 | Paramount Peptides · Thymosin Beta 4 (TB500) (10mg) | Nov 7, 2024 | Janoshik | Not reported | Not reported |
Doses reported in published studies: TB-500 (thymosin beta-4): doses reported in published research (literature summary, not advice).
Organ systems in published research: Brain & nervous system, Heart & blood vessels, Liver, Skin, Bone & cartilage, Eye, Lungs & airways.