[Therapeutic efficacy of a topical antifungal solution preparation formulated with pyrrolnitrin and clotrimazole in combination (Pyroace W) in guinea pig model of tinea pedis].

The therapeutic efficacy of a topical antifungal solution containing a mixture of 0.2% pyrrolnitrin and 0.4% clotrimazole (Pyroace W) was tested in a guinea pig model of tinea pedis using a 1% newly solution formulated preparation of miconazole (Dermalin-L) as a reference drug. Infected animals were treated once or twice daily with the testing drug and once daily with the reference drug for 4 weeks. Therapeutic efficacy was evaluated on the basis of the extent of the yield of fungal cultures from the infected skin tissues (infection intensity) and the relative number of culture-negative animals at the end of the treatment period. In an animal group treated once daily with the testing drug, the infection intensity was significantly lower than that for untreated or vehicle-treated control group (p < 0.0001) although there was no culture-negative animal. A similar extent of therapeutic efficacy was obtained with a once daily treatment with the reference drug, yielding one of ten culture-negative animal. A better efficacy was seen in animals treated twice daily with the testing drug; the infection intensity was further decreased to a significant level and eight of ten animals became culture-negative. These results demonstrated that twice daily treatment with the testing drug was highly effective in guinea pig model of tinea pedis, 80% of infected animals being mycologically cured. It confirms the clinical usefulness of this regimen in the treatment of patients with tinea pedis or other types of dermatophytosis.