FDA approves Kerydin topical solution for onychomycosis of the toenails

FDA approved tavaborole (Kerydin, Anacor Pharmaceuticals) topical solution, 5%, which is the first oxaborole antifungal approved for the topical treatment of onychomycosis of the toenails.

Tavaborole is a clear, colorless, alcohol-based solution that is applied with a dropper to the infected toenail once daily for 48 weeks. It is indicated specifically for onychomycosis caused by Trichophyton rubrum or Trichophyton mentagrophytes. Nail debridement is not necessary, according to Anacor.

Due to its topical application, tavaborole has low systemic absorption and has not demonstrated systemic side effects,

FDA determined the efficacy and safety of tavaborole based on 2 multicenter, double-blind, randomized trials involving 1,194 participants. The trials compared the drug with topical "vehicles" that carry an active dermatological ingredient.

Tavaborole or vehicle was applied once daily for 48 weeks in patients with 20% to 60% clinical involvement of the target toenail, without dermatophytomas or lunula (matrix) involvement. Assessments were made at 52 weeks after 48 weeks of treatment.

The primary end point was "complete cure," at week 52, defined as a completely clear nail (0% clinical involvement), plus mycologic cure, consisting of a negative KOH test and a negative culture. A complete cure was observed in 6.5% of patients using the product in trial 1 and 9.1% of those in trial 2 compared with 0.5% and 1.5%, respectively, of patients applying the vehicle.

Secondary end points included “complete or almost complete cure” (less than or equal to 10% affected target toenail area involved plus “mycological cure”). A total of 15.3% and 17.9% of patients treated with tavaborole achieved this endpoint, compared to 1.5% and 3.9% of patients treated with vehicle in the first and second trials, respectively.

"Kerydin was designed to be convenient for patients to use and has demonstrated efficacy in the treatment of the fungal infection, thus allowing growth of new uninfected nail," said Vince Ippolito, chief commercial officer of Anacor Pharmaceuticals, in a statement. "In market research conducted by Anacor, Kerydin's product profile was received with great enthusiasm by the participating physicians and we believe this response demonstrates the need for a safe topical treatment for onychomycosis of the toenails."