TP508 — EU research guide.

TP508 (Chrysalin, rusalatide acetate) is a 23-amino-acid fragment of human thrombin studied for accelerating wound, bone and vascular repair — in the same tissue-regeneration territory as BPC-157 and TB-500.

Last reviewed: 2026-07-04

What is TP508?

TP508 reproduces thrombin's receptor-binding domain without its clotting activity, activating repair pathways on endothelial cells, fibroblasts and osteoblasts. Preclinical work shows it promotes angiogenesis, reverses endothelial dysfunction and speeds fracture and wound healing.

What does the research show?

Human trials by OrthoLogic showed accelerated healing of chronic diabetic foot ulcers in a placebo-controlled phase I/II study, with no drug-related adverse events reported. A later placebo-controlled phase 2b trial in distal radius fractures found no benefit over placebo on the primary or secondary endpoints and was terminated after an interim analysis. More recent preclinical work has explored systemic TP508 for radiation injury and ARDS, but no product has reached full regulatory approval.

EU legal status

Not an approved medicine anywhere; sold by RUO peptide suppliers as a research chemical only, with batch-specific COAs available from specialised vendors.

⚠ Investigational compound; human trials used local, site-of-injury administration rather than systemic injection. Not evaluated for general self-administered use.

✓ For the more widely available regenerative research peptides, PeptideCompare tracks BPC-157 and TB-500 from EU research vendors with COA documentation.

EVIDENCE SUMMARY

MODERATE

Diabetic foot ulcer healing (phase I/II) — A placebo-controlled phase I/II trial reported accelerated healing of chronic diabetic foot ulcers with topical TP508 (Chrysalin) gel.

LIMITED

Fracture repair (phase 2b) — A placebo-controlled phase 2b trial in unstable distal radius fractures found no benefit over placebo on the primary endpoint (time to healing) or on secondary radiographic endpoints; the sponsor terminated the trial after an interim analysis (2006) and it was never published in a peer-reviewed journal.

Molecular information

Molecular formula

C97H146N28O36S

Molecular weight

2312.44 g/mol

CAS number

121341-81-9

Pharmacokinetics

No established human pharmacokinetic data. Published human PK parameters for this compound are not available; reported data are limited to animal models or absent. No curve is shown, to avoid implying data that does not exist.

Tissue-repair compounds across EU suppliers

COA-verified EU vendors · Updated monthly

References

Placebo-controlled phase I/II study showing TP508 (Chrysalin) accelerated healing of chronic diabetic foot ulcers. Fife C, et al. Wound Repair Regen. 2007;15(1):23–34. DOI PubMed 17244316
Review of preclinical mechanism data showing TP508 stimulates angiogenesis and repair signaling in dermal and musculoskeletal tissue models. Ryaby JT, et al. J Bone Joint Surg Am. 2006;88 Suppl 3:132–139. DOI PubMed 17079379