First clinical evaluation of the safety and efficacy of tarumase for the debridement of venous leg ulcers.

We report the first clinical evaluation of a new enzymatic wound debridement product containing tarumase in venous leg ulcer patients. As a first-in-human study, this was a prospective, open-label, multi-centre, dose escalation study across five dose cohorts and involving a total of 43 patients treated three times weekly for up to 4 weeks (12 applications). The primary and secondary endpoints of the study were to assess the systemic safety, local tolerability, and early proof of concept both for wound debridement and healing. Results indicated that the tarumase enzyme was well tolerated when applied topically to wounds, with no indications of systemic absorption, no evidence of antibody generation, and no systemic effects on coagulation pathways. Locally, there was no evidence of pain on application, no local itching, no increases in erythema, oedema, exudate or bleeding and only a few treatment emergent adverse events were reported. As the concentration of tarumase was escalated, trends towards faster and improved effectiveness of wound debridement were observed, especially in patients with significant slough at baseline. Trends towards faster rates of healing were also noted based on observations of increased granulation tissue, increased linear healing and reduction in surface area over the 4-week treatment period.

Preliminary evidence supporting a new enzymatic debridement product for use in chronic wounds.

A new recombinant proteolytic enzyme, isolated from maggot saliva, with fibrinolytic action has been investigated through a series of non-clinical toxicology and in-vitro/in-vivo pharmacology studies to explore its potential safety and efficacy as an enzymatic debridement agent for use in chronic wounds. Studies indicate that the enzyme has a good safety profile. When locally administered, it is not detrimental to wound healing, is non-sensitising and is rapidly inactivated in the systemic circulation. Adverse effects are limited, at very high concentrations, to transient erythema at the site of application. In-vitro testing indicates that the enzyme, whilst selective for fibrin, has additional proteolytic action against collagen and elastin, with enzymatic action for all three substrates being dose dependent. In-vivo, we used an established MRSA biofilm model, in which microbiological counts were used as a surrogate for debridement efficacy. Here, we showed that higher concentrations of the enzyme in a formulated proprietary gel, significantly reduced MRSA counts over a period of 2 to 14 days, and significantly improved the vascularity of the wound at 14 days. Together, these data support the potential for this maggot-derived proteolytic enzyme as a clinically effective debriding agent.