What is the most effective topical agent for onychomycosis (fungal infection of the toenail)?

From the Guidelines

The best topical agent for toenail fungus is Amorolfine 5% lacquer, applied once or twice weekly for 6-12 months, due to its broad-spectrum fungistatic and fungicidal activity and effectiveness in around 50% of cases of distal toenail onychomycosis. This recommendation is based on the British Association of Dermatologists' guidelines for the management of onychomycosis 2014 1. Amorolfine belongs to the morpholine group of synthetic antifungal drugs and inhibits the delta 14 reductase and delta 8 and delta 7 isomerase enzymes in the ergosterol biosynthetic pathway, making it fungicidal against C. albicans and T. mentagrophytes.

Some key points to consider when using Amorolfine 5% lacquer include:

• Applying the lacquer to the affected nail once or twice weekly for 6-12 months, after removal of as much of the diseased areas of the nail as possible by gentle filing
• The lacquer persists in the nail for 14 days after treatment is completed
• Clinical improvement obtained with Amorolfine may not be synonymous with mycological cure, which has invariably lower rates, often by 30%
• Amorolfine has also been found to be effective as a prophylactic treatment for recurrence of onychomycosis

While other options like Ciclopirox 8% lacquer are available, Amorolfine 5% lacquer has been shown to be more effective in treating toenail onychomycosis, with cure rates of around 50% compared to Ciclopirox's 34% mycological cure rate and 8% clinical cure rate 1. However, it's essential to note that topical treatments generally have lower cure rates compared to oral medications and require consistent long-term use. Complete resolution may take 9-12 months as the nail needs to fully grow out. For severe infections or those not responding to topical therapy, oral antifungals like terbinafine may be necessary. Keep nails trimmed, dry, and clean during treatment to prevent worsening or spreading of the infection.

From the FDA Drug Label

INDICATIONS AND USAGE ... Ciclopirox Topical Solution, 8%, (Nail Lacquer), as a component of a comprehensive management program, is indicated as topical treatment in immunocompetent patients with mild to moderate onychomycosis of fingernails and toenails without lunula involvement, due to Trichophyton rubrum The results of use of Ciclopirox Topical Solution, 8%, (Nail Lacquer), in treatment of onychomycosis of the toenail without lunula involvement were obtained from two double-blind, placebo-controlled studies conducted in the US

The best topical agent mentioned for toenail fungus is ciclopirox topical solution, 8% (nail lacquer), as part of a comprehensive management program, for mild to moderate onychomycosis without lunula involvement, due to Trichophyton rubrum 2.

• Key points:
  • Indicated for immunocompetent patients
  • Part of a comprehensive management program
  • Includes removal of unattached, infected nails by a healthcare professional
  • Not recommended with systemic antifungal agents for onychomycosis
  • Should be used only under medical supervision

From the Research

Topical Agents for Toenail Fungus

The following topical agents have been studied for the treatment of toenail fungus:

• Ciclopirox 8% nail lacquer: Studies have shown that ciclopirox 8% nail lacquer is effective in treating mild-to-moderate onychomycosis, with mycologic cure rates ranging from 29% to 36% 3, 4.
• Amorolfine 5% nail lacquer: Amorolfine 5% nail lacquer has been shown to be effective in treating onychomycosis, but its usage in monotherapy should be limited 5.
• Efinaconazole 10% solution: Efinaconazole 10% solution has been shown to be effective in achieving complete cure and mycological cure, with high-quality evidence supporting its use 6.
• Tavaborole 5% solution: Tavaborole 5% solution has been shown to be effective in achieving complete cure and mycological cure, with moderate-quality evidence supporting its use 6.
• P-3051 (ciclopirox 8% hydrolacquer): P-3051 has been shown to be effective in achieving complete cure, with moderate-quality evidence supporting its use 7, 6.
• Luliconazole 5% solution: The evidence for luliconazole 5% solution is uncertain, with very low-quality evidence supporting its use 6.

Comparison of Topical Agents

The following comparisons have been made between topical agents:

• Ciclopirox 8% lacquer vs. vehicle: Ciclopirox 8% lacquer is more effective in achieving complete cure and mycological cure 6.
• Efinaconazole 10% solution vs. vehicle: Efinaconazole 10% solution is more effective in achieving complete cure and mycological cure 6.
• Tavaborole 5% solution vs. vehicle: Tavaborole 5% solution is more effective in achieving complete cure and mycological cure 6.
• P-3051 (ciclopirox 8% hydrolacquer) vs. amorolfine 5%: P-3051 is probably more effective in achieving complete cure 7.

Adverse Events

The following adverse events have been reported with topical agents:

• Ciclopirox 8% lacquer: Application reactions, rashes, and nail alteration 6.
• Efinaconazole 10% solution: Dermatitis and vesicles 6.
• Tavaborole 5% solution: Application site reactions 6.
• P-3051 (ciclopirox 8% hydrolacquer): Erythema, rash, and burning 6.
• Luliconazole 5% solution: Dry skin, paronychia, eczema, and hyperkeratosis 6.