Results from a Phase 1/2 trial of BB2603, a terbinafine-based topical nano-formulation, in onychomycosis and tinea pedis.

BB2603 is a nano-formulation of the antifungal drug terbinafine with the polymer polyhexamethylene biguanide (PHMB) as an excipient to enhance solubility and drug delivery to skin and nails. BB2603 is delivered topically using a low-velocity spray. It is being developed in different strength formulations for the treatment of fungal infections of the nail and skin, including onychomycosis and tinea pedis, with BB2603-1 (0.01% terbinafine) tested in the present trial. The aim of this study was to assess systemic exposure, safety and tolerability of BB2603-1 compared with Lamisil® AT 1% spray and BB2603-1 vehicle control in onychomycosis and tinea pedis. Preliminary mycological and clinical activity were also investigated. This was a single-centre Phase 1/2, randomised, partially blinded, active- and vehicle-controlled, parallel-group trial in 46 subjects with onychomycosis associated with tinea pedis. Part 1 investigated BB2603-1 versus Lamisil AT 1% spray and BB2603-1 vehicle (4 weeks treatment). Part 2 investigated BB2603-1 versus BB2603-1 vehicle (additional 48 weeks treatment). No measurable systemic exposure of terbinafine was shown over 52 weeks of treatment with BB2603-1. BB2603-1 had an excellent safety and tolerability profile with no drug-related safety findings and no evidence of skin sensitisation. BB2603-1 showed preliminary evidence of anti-dermatophyte activity, demonstrated by a reduction in dermatophyte positive cultures and a reduction in microscopic evidence of dermatophytes. The pharmacokinetic, safety and efficacy data from this trial support further development of the topical terbinafine-based nano-formulation BB2603 in fungal infections of the skin and nail, including onychomycosis and tinea pedis.

Therapeutic improvement of scarring: mechanisms of scarless and scar-forming healing and approaches to the discovery of new treatments.

Scarring in the skin after trauma, surgery, burn or sports injury is a major medical problem, often resulting in loss of function, restriction of tissue movement and adverse psychological effects. Whilst various studies have utilised a range of model systems that have increased our understanding of the pathways and processes underlying scar formation, they have typically not translated to the development of effective therapeutic approaches for scar management. Existing treatments are unreliable and unpredictable and there are no prescription drugs for the prevention or treatment of dermal scarring. As a consequence, scar improvement still remains an area of clear medical need. Here we describe the basic science of scar-free and scar-forming healing, the utility of pre-clinical model systems, their translation to humans, and our pioneering approach to the discovery and development of therapeutic approaches for the prophylactic improvement of scarring in man.

Covering the limb--formation of the integument.

An organism's outermost covering, the integument, has evolved to fulfil a diverse range of functions. Skin provides a physical barrier, an environment for immunological surveillance, and also performs a range of sensory, thermoregulatory and biosynthetic functions. Examination of the skin of limb digits reveals a range of skin types including the thickened hairless epidermis of the toe pads (palmar or plantar epidermis) and thinner epidermis between the hair follicles (interfollicular epidermis) of hairy skin. An important developmental function of skin is to give rise to a diverse group of appendages including hair follicles, with associated sebaceous glands (or feathers and scales in chick), eccrine sweat glands and the nail. A key question is how does this morphological variety arise from the single-layered epithelium covering embryonic limb buds? This review will attempt to address this question by linking the extensive morphological/anatomical data on maturation of epidermis and its appendages with (1) current research into the range, plasticity and location of the putative epidermal stems cells; (2) molecular/microenvironmental regulation of epidermal stem cell lineages and lineage choice; and (3) regulation of the differentiation pathways, focusing on differentiation of the interfollicular epidermis.