Efficacy of terbinafine for toenail onychomycosis. A multicenter trial of various treatment durations.

The efficacy of terbinafine (250 mg/day) in the treatment of toenail onychomycosis was evaluated in a large open-label, multicenter trial of 12, 18, and 24 weeks of therapy. All 1,534 patients had onychomycosis, confirmed by either positive potassium hydroxide (KOH) wet mount, positive fungal culture, or both, and all received at least 12 weeks of treatment. Treatment was continued for an additional 6 or 12 weeks, depending on the extent of the disease at follow-up. Mycologic cure rates (negative culture plus negative KOH) at week 72 were 72.1% in the 12-week treatment group, 72.5% in the 18-week group, and 77.0% in the 24-week group. In all groups, clinical cure rates were higher at week 72 than at week 48: 49.5% of the 12-week group, 49.2% of the 18-week group, and 44.6% of the 24-week group experienced clinical cure by the end of the study. Both mycologic and clinical recurrence rates were low in all treatment groups at the 72-week assessment. The results of this study confirm the efficacy of terbinafine in the treatment of toenail onychomycosis as demonstrated in previous registration and large-scale clinical trials.