BETHESDA, MD 08 Jul 2014—Anacor Pharmaceuticals Inc. this morning announced that FDA has approved tavaborole topical solution, or Kerydin, for the treatment of toenail onychomycosis caused by Trichophyton rubrum or Trichophyton mentagrophytes.
The boron-based drug, according to the product's labeling (PDF), decreases fungal protein synthesis by inhibiting the activity of a transfer RNA synthetase.
Treatment of a toenail with onychomycosis involves once-daily application of the antifungal solution for 48 weeks. The three-page "Instructions for Use" tells patients to apply a sufficient amount of the solution, one drop at a time, to completely cover the affected toenail. Patients should use the pointed tip of the product's glass dropper to spread the solution over the entire toenail up to its edges and also under the nail's entire tip. Applications should avoid the skin surrounding the toenail.
In the two placebo-controlled studies of tavaborole topical solution, daily application for 48 weeks resulted in a complete or almost complete cure at week 52 in one sixth of the patients, according to the labeling.
The most commonly reported adverse reactions to tavaborole topical solution during those studies were skin peeling, ingrown toenail, erythema at the application site, and skin inflammation at the application site. None of these reactions occurred in more than 2.7% of the patients.
The antifungal product will be supplied in amber screw-cap glass bottles containing 10 mL of 5% tavaborole solution. Each bottle will come with a glass pointed-tip dropper. Before removing the first dose from a bottle, the patient must replace the screw cap with the dropper. The labeling instructs patients to safely discard the solution, bottle, and dropper within three months after first inserting the dropper into the bottle.
Kerydin contains alcohol. The labeling states that the solution is flammable and should be kept away from heat and flame. The product must be kept out of the reach of children.
Anacor said it expects to make its topical antifungal product available as early as this September.