Efficacy and safety of naftifine HCl Gel 2% in the treatment of interdigital and moccasin type tinea pedis: pooled results from two multicenter, randomized, double-blind, vehicle-controlled trials.

Background: Tinea pedis is the most common chronic fungal infection. Naftifine hydrochloride is a topical antifungal of the allylamine class, displaying fungicidal activity and clinically significant anti-bacterial and anti-inflammatory effects.

Objective: To evaluate the efficacy and safety of two-weeks once daily application of naftifine gel 2% in the treatment of tinea pedis.

Methods: At baseline, 1715 subjects were randomly assigned 2:1 to naftifine gel 2% (n=1144) and vehicle (n=571). Efficacy consisting of mycologic determination (KOH and dermatophyte cultures) and scoring of clinical symptom severity was evaluated at baseline and weeks 2, 4, and 6. Efficacy was analyzed in 1174 subjects (n=782, naftifine; n=392, vehicle) with a positive baseline dermatophyte culture and KOH for whom week 6 assessments were available. Safety was evaluated by adverse events (AE) and laboratory values in 1714 subjects (n=1143, naftifine; n=571, vehicle).

Results: Subjects treated with naftifine gel 2% for interdigital-type tinea pedis demonstrated greater improvement from baseline for complete cure (P=0.001), mycological cure (P<0.0001), and treatment effectiveness (P<0.0001) as early as 2 weeks when compared to vehicle; however the highest response rates were seen 4-weeks post treatment (P<0.0001, for all endpoints). Statistically significant results for complete cure, mycological cure, and treatment effectiveness (P<0.0001, for all endpoints) were also seen at week 6 among subjects with moccasin-type tinea pedis. Treatment related adverse events were minimal.

Conclusions: Treatment with naftifine gel 2% applied once daily for two weeks is well-tolerated and is effective in treating both interdigital-type and moccasin-type tinea pedis. Continuous improvement is observed from the end of treatment to four-weeks after treatment cessation among key outcome measures (complete cure, mycological cure, and treatment effectiveness) as well as clinical signs and symptoms (erythema, scaling, and pruritus)