The purpose of this clinical trial is to determine the safety and effectiveness of the medical device ABL01. The intended use of ABL01 is to reduce and treat onychomycosis, fungal nail infection. ABL01 is a solution intended to be topically administered weekly to infected nails. The trial is designed as a double blinded randomized placebo controlled clinical trial. The trial involves 70 study subjects, half of which will receive ABL01 and the other half placebo. The inclusion criteria for study subjects are adult men and women that present with distal lateral subungual onychomycosis (DSU) on the big toe nails. Furthermore, the extent of DSU should not involve more than half of the area of the nail.