TB500 bụ peptide nwere ọtụtụ akụkụ emepụtara n'ime ụlọ nyocha. Ọ nwere otu nhazi na ọrụ ya na Thymosin Beta 4 nke gland thymus na-emepụta n'ime ahụ. TB500 na  Thymosin Beta 4 ha abụọ nwere amino acid 43 n'otu n'otu ma nwee otu mmetụta ahụ na ọgwụgwọ na mgbake. Na nkenke, TB500 bụ ụdị synthetic nke Thymosin Beta 4. Ya mere, anyị na-eji aha abụọ ahụ emekọrịta ihe n'ihi na mmetụta niile bụ otu.