Efficacy of MMP-inhibiting wound dressings in the treatment of hard-to-heal wounds: a systematic review

Objective: Matrix metalloproteinases (MMPs) substantially contribute to the development of chronicity in wounds. Thus, MMP-inhibiting dressings may support healing. A systematic review was performed to determine the existing evidence base for the treatment of hard-to-heal wounds with these dressings. Methods: A systematic literature search in databases and clinical trial registers was conducted to identify randomised controlled trials (RCTs) investigating the efficacy of MMP-inhibiting dressings. Studies were analysed regarding their quality and clinical evidence. Results: Of 721 hits, 16 relevant studies were assessed. There were 13 studies performed with collagen and three with technology lipido-colloid nano oligosaccharide factor (TLC-NOSF) dressings. Indications included diabetic foot ulcers, venous leg ulcers, pressure ulcers or wounds of mixed origin. Patient-relevant endpoints comprised wound size reduction, complete wound closure, healing time and rate. Considerable differences in the quality and subsequent clinical evidence exist between the studies identified. Substantial evidence for significant improvement in healing was identified only for some dressings. Conclusion: Evidence for the superiority of some MMP-inhibiting wound dressings exists regarding wound closure, wound size reduction, healing time and healing rate. More research is required to substantiate the existing evidence for different types of hard-to-heal wounds and to generate evidence for some of the different types of MMP-inhibiting wound dressings.