Phase 3 Randomized Study of Efficacy and Safety of a Dexamethasone Intracanalicular Insert in Patients With Allergic Conjunctivitis

PURPOSE: The purpose of this study was to evaluate the efficacy and safety of a dexamethasone intracanalicular ocular insert for the treatment of allergic conjunctivitis. DESIGN: Multicenter, randomized, double-masked, placebo-controlled, Phase 3 clinical trial. METHODS: Subjects with allergic conjunctivitis were randomized 1:1 to receive a dexamethasone insert or a placebo insert in both eyes and were evaluated using a modified version of the conjunctival allergen challenge (CAC) model. After inserts were placed in office, a series of 4 closely spaced post-insertion CACs were conducted at weeks 1, 2, and 4 across approximately 30 days. Primary efficacy endpoints, assessed at week-1 CAC-day 8, were reported by subjects of ocular itching at 3, 5, and 7 minutes post CAC and investigator-evaluated conjunctival redness at 7, 15, and 20 minutes post CAC. RESULTS: For the primary endpoints, dexamethasone inserts showed statistically significantly lower mean ocular itching scores than placebo at all time points (P < .001), with differences favoring dexamethasone inserts over placebo (0.86, 0.98, and 0.96 units at 3, 5, and 7 minutes, respectively) and statistically significantly lower conjunctival redness scores at 20 minutes (P < .05) but not at 7 or 15 minutes (P >= .05). Results also showed statistically significantly less itching and conjunctival redness at 31 and 29 of 33 other time points, respectively (P < .05). There were no serious adverse events; 1 subject had elevated intraocular pressure in both eyes. CONCLUSIONS: Data presented in this study demonstrate the potential for a single, physician-administered dexamethasone intracanalicular insert to provide relief of ocular itching for up to 4 weeks in subjects with allergic conjunctivitis, while maintaining a favorable safety profile. (C) 2021 The Authors. Published by Elsevier Inc.