Evaluating Sustained-Release Dexamethasone for the Treatment of Chronic Allergic Conjunctivitis Using a Modified Conjunctival Allergen Model

Saturday, April 18, 2015: 1:52 PM
Room 1A (San Diego Convention Center)
Eugene B. McLaurin, MD
Gail L. Torkildsen, MD
Paul J. Gomes, MS

Purpose
To evaluate the efficacy and safety of OTX-DP as a one-time administered sustained release drug (dexamethasone) depot when placed in the canaliculus of the eyelid for the treatment of the signs and symptoms of chronic allergic conjunctivitis.

Methods
Subjects underwent a series of allergen challenges using the Ora-CAC model to induce the inflammatory component of chronic allergic conjunctivitis.  After showing a reproducible CAC for itching and redness, and meeting eligibility criteria, subjects were randomized (1:1) at Day 1 to receive OTX-DP or Placebo Vehicle Punctum Plug (PV), bilaterally. The primary efficacy measures (ocular itching and conjunctival redness) were assessed at 14 days post-insertion. Subjects were followed further at 4 weeks and 6 weeks post-insertion for assessing continued therapeutic effect for allergic conjunctivitis.

Results
35 and 33 subjects were randomized to OTX-DP and PV, respectively.   At 14 days post-insertion, OTX-DP was statistically superior to PV in ocular itching and conjunctival redness at all-time points (3, 5, and 7 minutes for itching and 7, 15, and 20 minutes for redness) post-CAC. The differences (p-values) observed for itching and redness, were respectively: -0.78 (0.0031), -0.98 (0.0002), -0.88(0.0007), and -0.51 (0.0100), -0.70 (0.0006), -0.67 (0.0008). The treatment difference was > 0.5 units for itching and redness at 2, 4, and 6 weeks, showing consistent efficacy on itching and redness. No serious treatment-related adverse events were noted in either group.

Conclusion
Overall, OTX-DP treatment was shown to be efficacious, safe and well tolerated.  Treatment effects were evident for at least 6 weeks.  The data supports the continued development of this drug product in the Ora-CAC model.