BRD2 and fungal keratitis: This antifungal agent fights off a wide range of pathogenic filamentous fungi and yeast through direct contact with the corneal ulcer surface.18,19 Nevertheless, data from several studies suggest that patients with moderate to severe fungal keratitis respond poorly to NAT as a monotherapy.20,21 The mechanism underlying its antifungal activity is closely associated with a special component known as a tetraene polyene antibiotic.