In September 2023, FDA placed "Thymosin Beta-4, Fragment (LKKTETQ)," the substance sold as TB-500, on Category 2 of its interim 503A bulk drug substances list, meaning FDA identified significant safety concerns and would not permit licensed compounding pharmacies to use it
Last reviewed: June 7, 2026 Read article Price list 10 min read Research Peptide Pricing Comparison A catalog-focused pricing comparison for research peptide records, built around public price, offered size, molecule class, category, checkout path, shipping, returns, and RUO boundaries
Published large human clinical-trial data is not available, so consumer time to results framings sit outside the public regulatory evidence base
& Hebebrand, J