Under review
Thymosin beta-4 is listed in the CompoundedGuide registry with no verified FDA-approved product. FDA lists Thymosin beta-4 among bulk drug substances for use in compounding that may present significant safety risks. Thymosin beta-4 is not on FDA's 503B Bulks List for outsourcing facilities (list checked 2026-07-25). 18 registered ClinicalTrials.gov studies cite Thymosin beta-4 (11 completed, 2 recruiting, 2 terminated, 2 withdrawn, 1 not yet recruiting); registration is not evidence of approval, efficacy, or safety. Identity and regulatory status are pending source collection and editorial review. This is not medical advice.