In Vitro Resistance and Evolution of Resistance to Tavaborole in Trichophyton rubrum

Antimicrob Agents Chemother. 2021 Mar 18;65(4):e02324-20. doi: 10.1128/AAC.02324-20. Print 2021 Mar 18.

Abstract

Tavaborole is currently used in the topical treatment of onychomycosis. In this study, we analyzed the in vitro emergence/evolution of resistance against tavaborole in Trichophyton rubrum When T. rubrum strains were propagated on media containing the MIC of tavaborole, spontaneous resistant mutants were isolated at a frequency of 10-8 The frequency was almost 100-fold higher following fungal growth in the presence of a subinhibitory tavaborole concentration (0.5-fold the MIC) for 10 transfers. All collected mutants showed similar 4- to 8-fold increases in the drug MIC. No cross-resistance to other antifungals was evident.

Keywords: Trichophyton rubrum; cross-resistance; onychomycosis; resistance; tavaborole.

MeSH terms

  • Antifungal Agents / pharmacology
  • Antifungal Agents / therapeutic use
  • Arthrodermataceae
  • Boron Compounds
  • Bridged Bicyclo Compounds, Heterocyclic
  • Humans
  • Onychomycosis* / drug therapy
  • Trichophyton / genetics

Substances

  • Antifungal Agents
  • Boron Compounds
  • Bridged Bicyclo Compounds, Heterocyclic
  • tavaborole

Supplementary concepts

  • Trichophyton rubrum