Effect of the vehicle on the topical itraconazole efficacy for treating corneal ulcers caused byAspergillus fumigatus

A bstract Background: The clinical behaviour of mycotic keratitis is aggressive, and the options for treating it are limited. This poses a need to explore new options for efficacious, low‐cost treatment. Recent evidence suggests that topical itraconazole may be useful for treating this entity and that it may be possible to improve its efficacy using a suitable vehicle. Methods: We included 12 New Zealand white (NZW) rabbits (24 eyes). The rabbits were infected with pathogenic strains of Aspergillus fumigatus and subsequently randomized to receive every 2 h for 5 weeks two different preparations of topical itraconazole 1%. In group 1 (12 eyes), ricinus oil and in group 2 (12 eyes), Systane were used as vehicle. Rabbits were evaluated every week by a masked ophthalmologist to determine the treatment response. Results: The size of the ulcers was similar in the two groups at the baseline: group 1: 12.7 ± 2.7 mm (median 12.8, range 9.8–15.5 mm); and group 2: 12.3 ± 3.1 mm (median 12.1, range 9.8–20.8; P = 0.67). Although both groups responded well to the treatment, the response was better in the group 2, especially in weeks 2 and 3: week 1: 12.7 ± 2.7 vs. 9.3 ± 4.61 mm ( P = 0.1); week 2: 9.4 ± 3.4 vs. 4.1 ± 2.9 mm ( P = 0.004); week 3: 5.0 ± 3.4 vs. 1.7 ± 1.0 mm ( P = 0.004); week 4: 1.9 ± 1.9 vs. 1.0 ± 1.2 mm ( P = 0.1); and week 5: 0.68 ± 1.2 vs. 0.0 ± 0.0 mm ( P = 0.3). Conclusion: Topical itraconazole may be useful for treating corneal ulcers caused by Aspergillus fumigatus , and its efficacy seems to be related with the vehicle solubility.