Rusalatide acetate

Summary

Rusalatide acetate (also known as TP508 or Chrysalin) is a synthetic peptide under investigation for tissue‑repair applications. Preclinical and early‑phase clinical studies have examined its ability to mitigate radiation‑induced gastrointestinal injury, accelerate healing of chronic diabetic foot ulcers, and promote bone fracture repair. The compound is delivered locally or by injection and remains an investigational agent rather than an approved medication.

Mechanism of Action

Rusalatide acetate binds to yet‑identified cell‑surface receptors, initiating nitric‑oxide signaling cascades that enhance cellular proliferation and survival. In the gastrointestinal tract it up‑regulates stem‑cell markers LGR5 and DCLK1, stabilises adherens‑junction protein E‑cadherin, and reduces apoptosis, thereby preserving crypt architecture. In wound and bone models the peptide stimulates nitric‑oxide‑mediated pathways that support angiogenesis, extracellular‑matrix formation, and osteogenic activity, collectively fostering tissue regeneration.

What the Research Shows

A 2015 laboratory investigation demonstrated that a single injection of rusalatide acetate given 24 hours after a lethal 9 Gy radiation dose protected intestinal crypts, activated stem‑cell markers, and improved survival in mice. An expert opinion article from 2008 reported Phase I/II trials in which the peptide accelerated healing of diabetic foot ulcers and distal‑radius fractures; however, a subsequent large Phase III fracture study failed to meet its primary endpoint of earlier immobilisation removal, though a subgroup of osteopenic women showed significant radiographic benefit. A 2020 systematic review of randomized trials identified rusalatide acetate among 26 studies of growth‑factor therapies for diabetic ulcers, noting that only a few trials have examined this peptide and that no adverse events were reported. Overall, evidence is limited to early‑phase and small‑scale studies.

Reported Benefits

Available data suggest that rusalatide acetate can (1) improve survival and preserve gut integrity after high‑dose radiation exposure, (2) hasten closure of diabetic foot ulcers in early clinical trials, and (3) accelerate radiographic bone healing, particularly in patients with reduced bone density. These effects are attributed to stem‑cell activation, nitric‑oxide signaling, and enhanced tissue remodeling.

Limitations of the Evidence

The peptide has not achieved regulatory approval and its efficacy remains uncertain. The Phase III fracture trial did not meet the primary clinical endpoint in the overall intent‑to‑treat population, and the systematic review highlighted a paucity of robust, homogeneous trials for diabetic ulcer treatment. Evidence is therefore confined to small Phase I/II studies and preclinical models, limiting confidence in long‑term outcomes and broader applicability.

Safety Considerations

No adverse events were reported in the systematic review of diabetic‑ulcer trials, and the radiation‑damage study did not describe safety concerns. Nevertheless, the safety profile of rusalatide acetate is incompletely defined, given the limited size and duration of existing trials. Caution is warranted until larger, controlled studies provide more comprehensive safety data.

How It Is Administered

Rusalatide acetate can be administered intralesionally, subcutaneously, or as a topical preparation. The radiation‑mitigation study employed a single injection, while wound‑healing investigations used local injections at the ulcer site. Specific formulation details and dosing regimens have not been disclosed in the published literature.

Routes of Administration

Goals & Uses

• Diabetic foot ulcer healingWound HealingModerate
• Angiogenesis promotionVascularModerate
• Re-epithelializationWound HealingModerate
• Fracture repair accelerationOrthopedic / Bone HealingModerate

Contraindications

• Active malignancy at or near wound siteOncologyHigh
• Known hypersensitivity to rusalatide or thrombin-derived peptidesAllergyHigh

Adverse Effects

• HeadacheNeurologicUncommonPain in the head or upper neck
• Local injection/application site reactionsLocalCommon
• Wound infectionInfectiousUncommon

Drug Interactions

• AnticoagulantsLowMonitor when nausea or vomiting affects intake

Population Constraints

• Severe renal or hepatic impairmentOrgan FunctionRelative
• PregnancyReproductive SafetyRelative
• Pediatric patientsAgeRelative

Regulatory Status

• European UnionUnknownNo EMA approval or formal regulatory filing identified.
• United StatesInvestigationalIND status granted; Phase II/III trials conducted for diabetic foot ulcers and fracture healing. No NDA filed; program discontinued.
• United KingdomUnknownNo MHRA approval or filing identified.

Rusalatide acetate (TP508) was studied in Phase II and Phase III clinical trials for diabetic foot ulcers and bone fracture healing. The FDA granted it Investigational New Drug (IND) status. It did not receive FDA approval; development by Chrysalis BioTechnology was discontinued after trials showed inconsistent efficacy results.

Evidence & Sources

• Novel regenerative peptide TP508 mitigates radiation-induced gastrointestinal damage by activating stem cells and preserving crypt integrity
  Journal ArticleLowKantara C, et al.2015-01-01T00:00:00.000000Z
• Could rusalatide acetate be the future drug of choice for diabetic foot ulcers and fracture repair?
  Journal ArticleModerateCarney DH, Olszewska-Pazdrak B2008-01-01T00:00:00.000000Z
• The Role of Recombinant Proteins and Growth Factors in the Management of Diabetic Foot Ulcers: A Systematic Review of Randomized Controlled Trials
  Journal ArticleHighMahdipour E, Sahebkar A2020-01-01T00:00:00.000000Z
• Gateways to clinical trials
  Journal ArticleLowBayés M, Rabasseda X, Prous JR2007-01-01T00:00:00.000000Z

Frequently Asked Questions