Progress in topical nanoformulations against bacterial skin and soft tissue infections- current trends

The accelerating rate of antibiotic resistance has always been one of the leading causes of increased skin and soft tissue infections (SSTIs) burden around the globe. Current treatments mainly focus on systemic antibiotics indicated for both uncomplicated and complicated SSTIs that act as a contributing factor secondary to widespread systemic exposure. Topical formulation of antibacterial agents or antibiotics are renowned for their targeted and localised action in the skin which appears as an intriguing clue to the resistance problem. Nevertheless, there are several deterrents associated with conventional topical formulations including drug permeability and skin retention. This has propelled the transformation of SSTI intervention towards the incorporation of nanotechnology to enhance topical drug delivery for SSTIs. This review outlines the advancement of nanoparticle-based topical formulations against SSTIs, covering cellulitis and erysipelas, boils and carbuncles, impetigo, cutaneous non-tuberculous mycobacterial infections and leprosy, as well as pitted keratolysis. Pre-clinical safety profile and antibacterial efficacy of topical nanoformulations were comprehensively reviewed and classified into multiple categories such as metal nanoparticles, emulsion-based nanosystems, nanovesicles, lipid nanoparticles and polymeric nanoparticles. The up-to-date patent trends on topical nanoformulations for SSTIs up to 2025 were also analysed and justified based on current evidence to pinpoint the research gap and future prospects in this growing area of research. It is anticipated that topical nanoformulations can potentially stand in for conventional topical formulations to treat SSTIs attributed to their pronounced antibacterial activity and tolerability.