The purpose of this study is to evaluate the safety and efficacy of topical application of IDP-108 versus vehicle in treating patients with onychomycosis.

Inclusion Criteria:

• Clinically diagnosed onychomycosis of the target nail
• Presence of mild to moderate onychomycosis, defined as 20 - 50% of the area of the target nail being clinically affected
• Has a positive KOH examination from the target nail
• Has a positive dermatophyte culture from the target nail

Exclusion Criteria:

• Presence of any disease or condition that might cause nail abnormalities or may interfere with the evaluation of the study drug
• Use of any systemic antifungal therapy within 4 weeks prior to the Screening visit or non-responsive to systemic antifungal therapy for onychomycosis
• Use of any prescription or over-the-counter topical antifungal therapy for the toenails within 4 weeks prior to the Screening visit
• Woman who is pregnant, nursing an infant, or planning a pregnancy during the study period