Efinaconazole Topical Solution, 10%: Factors Contributing to Onychomycosis Success

Abstract

To provide an adequate therapeutic effect against onychomycosis, it has been suggested that topical drugs should have two properties: drug permeability through the nail plate and into the nail bed, and retention of their antifungal activity in the disease-affected areas. Only recently has the importance of other delivery routes (such as subungual) been discussed. Efinaconazole has been shown to have a more potent antifungal activity in vitro than the most commonly used onychomycosis treatments. The low keratin affinity of efinaconazole contributes to its effective delivery through the nail plate and retention of its antifungal activity. Its unique low surface tension formulation provides good wetting properties affording drug delivery both through and under the nail. High antifungal drug concentrations have been demonstrated in the nail of onychomycosis patients, and effectiveness of efinaconazole topical solution, 10% confirmed in two large well-controlled multicenter Phase 3 clinical studies in patients with mild-to-moderate disease.

Keywords: efinaconazole; fungi; onychomycosis; toenail; topical therapy.

Figure 1

Baseline (natural light) and post clipping (UV light) photographs of three representative patients. Subject 005: 55% nail involvement; subject 011: 35% nail involvement; subject 014: 40% nail involvement. In all subjects efinaconazole vehicle solution was applied to the hyponychium only. See [33] for detailed methodology and results.

Figure 2

Baseline and study end (week 52) photographs of three representative patients. Subject 110–001: 25% nail involvement at baseline and 0% nail involvement at week 52; subject 111–025: 50% nail involvement at baseline and 10% nail involvement at week 52; subject 127–038: 45% nail involvement at baseline and 1% nail involvement at week 52. All subjects treated with efinaconazole topical solution, 10% daily for 48 weeks. See [15] for detailed methodology and results.