A Phase III clinical study to evaluate the efficacy of combined azithromycin and dexamethasone in the treatment of blepharoconjunctivitis

Kamran Hosseini,^1,2 Judith Hutcheson,¹ Richard L Lindstrom<sup>3–5

1</sup>Clinical Affairs, ²Regulatory Affairs, InSite Vision Incorporated, Alameda, CA, USA; ³Minnesota Eye Consultants, Bloomington, MN, USA; ⁴University of Minnesota Department of Ophthalmology, Minneapolis, MN, USA; ⁵University of California, Irvine Gavin Herbert Eye Institute, Irvine, CA, USA

Purpose: The purpose of this study was to evaluate the clinical and antimicrobial efficacy and safety of ISV-502 (1.0% azithromycin and 0.1% dexamethasone) compared to 1.0% azithromycin or 0.1% dexamethasone in the treatment of subjects with blepharoconjunctivitis.
Patients and methods: Patients with verified blepharoconjunctivitis were randomized to receive ISV-502 (Group 1; n=140), 1.0% azithromycin alone (Group 2; n=141), or 0.1% dexamethasone alone (Group 3; n=136). Bacterial cultures were obtained from the conjunctiva and eyelid. Treatment was instilled in both eyes twice daily at 12-hour intervals for 14 days. The primary endpoint was complete resolution of clinical signs and symptoms at Day 15. The secondary endpoint was complete bacterial eradication at Day 15 among subjects with positive bacterial cultures at baseline.
Results: Significantly more Group 1 subjects met the primary endpoint (27.1%) than those in Group 2 (15.6%; P=0.028), but not compared to Group 3 (23.5%; P=0.581). Significantly more Group 1 patients (60%) had complete bacterial eradication at Day 15 compared with Group 3 (40.2%; P=0.007), but there was no difference compared with Group 2 (66.3%; P=0.306). Adverse events were reported in about 25% of the subjects, with an equal distribution among treatment arms; the most common adverse event was irritation at the instillation site. Visual acuity and intraocular pressure differences were not statistically significant, but did show age and sex differences between groups.
Conclusion: ISV-502 is effective in the treatment of blepharoconjunctivitis as evaluated by clinical cure and bacterial eradication scores. ISV-502 was superior to 1.0% azithromycin in clinical cure and superior to 0.1% dexamethasone in bacterial eradication.

Keywords: blepharitis, inflammation, eye