Luliconazole (LLCZ) is an imidazole antifungal agent demonstrating superior in vitro antifungal activity against dermatophytes than other topical antifungal agents. 

A study assessed the viability of pathogenic fungi during LLCZ topical treatment for tinea pedis. The study cohort included patients with tinea pedis, as confirmed by positive KOH examinations. Patients with a history of the use of antimycotic therapy during the previous 12 months were excluded from the study. All the enrolled patients in the study were treated with topical 1% LLCZ cream, solution, or ointment once daily for 4 weeks. 

Scales from the affected sites were collected at the initial visit and at 2 and 4 weeks after initiation of therapy, which was then subjected to KOH examination, fungal culture, and qPCR assays. 

The study included 13 patients with tinea pedis. The eight patients were diagnosed with an intertriginous type of tinea pedis, five with vesiculobullous type, while four patients also had tinea unguium. Because of incomplete follow-up by 2 patients, 12 and 11 patients were evaluated at 2 and 4 weeks, respectively. 

At week 4-All patients showed clinical signs of improvement compared with the initial visit,

No scale was observed in one patient who reached complete cure. 

At the start of the study (initial visit)-100% of patients had positive KOH examination, 

77% had positive fungal culture,100% had positive qPCR. 

After 2 weeks of treatment-100% samples were negative for fungal culture, 

83% were positive on KOH examination, 92% were positive by qPCR. 

At 4 weeks-30% of patients were positive on KOH examination,14% was positive for fungal culture, 40% were positive by qPCR. 

Thus the study proved qPCR assay to be more sensitive than KOH examination and fungal culture in assessing the viability of pathogenic fungi during LLCZ topical treatment. No significant difference in the ITS DNA copy number (599–244,511 copies/mg) was found in the infected specimens from tinea pedis patients at the initial visit as compared to that of tinea unguium.

LLCZ demonstrated eradication of almost all pathogenic dermatophytes in the scales, with six patients revealing negative results for the mycological examinations and qPCR at week 4. No significant differences were found in sex, age, infection type, and combination of tinea unguium between patients with negative and positive results for mycological examinations and qPCR assays.

Nearly 5% of dermatophytes in the scales showed survival despite the topical application of 1% LLCZ, achieving a concentration approximately 8000-fold greater than the MFC. 

This study explained the complete cure mechanism of tinea pedis by LLCZ topical treatment. It also demonstrated the elimination of approximately 95% of pathogenic dermatophytes in the scale after 4 weeks of 1% LLCZ topical treatment and reported that LLCZ application results in nearly 5% of surviving dermatophytes in the dormant state until desquamation of the infected scales.

Source: Iwanaga T, Ushigami T, Anzawa K, Mochizuki T. Viability of pathogenic dermatophytes during a 4-week treatment with 1% topical luliconazole for tinea pedis. Med Mycol. 2020;58(3):401-403. doi:10.1093/mmy/myz056