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

Abstract

The purpose of this study was to evaluate the efficacy and safety of a dexamethasone intracanalicular ocular insert for the treatment of allergic conjunctivitis. Multicenter, randomized, double-masked, placebo-controlled, Phase 3 clinical trial. 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. 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. 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.