TB-500

• Recovery supportrecommended

  Community practice, not from a label or trial: the low end of 2-5 mg, 2-3 times a week. The source says it has no clinical basis.

• Community practice, not from a label or trial: 2 to 5 mg per administration, 2 to 3 times per week, subcutaneous. The page calls this the "typical marketing dose" and says it has "no clinical basis".
• Loading or maintenance phases and cycle length: not stated in the source.
• For context only: full-length synthetic thymosin beta-4 was given IV at 42 to 1,260 mg, single and daily for 14 days, to healthy adults with infrequent mild-to-moderate adverse events (PubMed 20536472). That is a different molecule and route.

Route: Subcutaneous (community figure). The fragment has no sourced human route.

Timing: No reliable figure found in the sources; ask your prescriber or supplier.

• Placeholder 5 mg vial plus 1 mL gives 5 mg/mL, so 2 mg is 40 units. This is arithmetic, not a sourced instruction.

No reliable figure found in the sources; ask your prescriber or supplier.

No reliable figure found in the sources; ask your prescriber or supplier.

Why:

• The source gives no cycle length or rest period.

• Never draw into the same syringe as another compound; use separate syringes and distinct injection sites.

Not an FDA-approved drug. FDA removed it from the 503A Category 2 list on April 15 2026 because the nominators withdrew, which does not make it compoundable; a July 2026 advisory committee recommendation is not yet a rule. Check current status.

Common side effects:

• No human safety data for the fragment were found.
• Full-length thymosin beta-4 IV trials in healthy adults reported infrequent mild-to-moderate events (PubMed 20536472); this does not cover the fragment or subcutaneous use.

Stop and call your prescriber if:

• Swelling, redness or pain spreading from the injection site
• Rash, hives or trouble breathing
• Any new unexplained symptom

No reliable source names a biomarker for this compound.

• Cayman Chemical TB-500 (acetate): Ac-LKKTETQ, residues 17-23 of thymosin beta-4
• PubMed 22962027: Ac-LKKTETQ identified in a commercial TB-500 product (Esposito 2012)
• Aging wiki TB-500 page: marketing dose and evidence statement (secondary source)
• PubMed 20536472: phase 1 of full-length synthetic thymosin beta-4, IV, healthy volunteers
• Frier Levitt: FDA removes 12 peptides from Category 2 (April 2026)
• McDermott: advisory committee backs most peptides for the 503A list (July 2026)