Vehicle-Controlled, Phase 2 Clinical Trial of a Sustained-Release Dexamethasone Intracanalicular Insert in a Chronic Allergen Challenge Model

DEXTENZA versus Topical Steroid or Antihistamine Therapy for Treatment of Allergic Conjunctivitis

Purpose

To compare clinical outcomes and patient preference for the dexamethasone intracanalicular insert (DEX) versus topical loteprednol (LOT) or olopatadine (OLO) for the treatment of allergic conjunctivitis in a real-world model of allergen exposure.

Methods

This was a prospective comparative trial. Adults with testing-confirmed bilateral allergic conjunctivitis received DEX in the more symptomatic eye and either LOT 2 times daily or OLO once daily for 30 days in the fellow eye. The primary outcome was patient preference for treatment. Clinical outcomes included ocular itching and hyperemia, lid swelling, and watering/tearing. Safety outcomes included intraocular pressure (IOP).

Results

Thirty patients participated and completed the study. All received DEX in the eye with worse symptoms and 15 received LOT and the other 15 received OLO in the other eye. Patients preferred DEX (10/15; 66.7%) over LOT (4/15; 26.7%), with one patient having no preference (p = 0.0103). Patients had no preference between DEX (8/15; 53.3%) and OLO (6/15; 40%), with one patient having no preference (p = 0.1044). In the DEX/LOT cohort, ocular itching and hyperemia improved more with DEX than LOT (p ≤ 0.009), while in the DEX/OLO cohort, the DEX eyes showed greater improvement in conjunctival hyperemia (p < 0.0001) but not itching (p = 0.074). No between-group differences were seen in eyelid swelling or tearing/watering in either cohort. Mean change in IOP was similar between the DEX and LOT eyes (p = 0.4921), and mean IOP rose more in the DEX eyes than the OLO eyes (by <1 mmHg; p = 0.0403).

Conclusion

Overall, this real-world study demonstrated that the dexamethasone intracanalicular insert was as effective as a topical antihistamine/mast cell stabilizer and more effective than topical steroids in relieving the signs and symptoms of allergic conjunctivitis. This insert should be considered as an alternative to topical therapy for the treatment of allergic conjunctivitis.

Effects of Punctal Occlusion on Ocular Itching and Conjunctival Redness Associated with Allergic Conjunctivitis

PURPOSE

Punctal occlusion using punctal plugs has been successfully used to treat the signs and symptoms of dry eye disease. However, the effects of punctal occlusion on the symptoms of allergic conjunctivitis (AC) have been less well documented. There is some concern among clinicians that punctal occlusion may make signs/symptoms of allergic conjunctivitis worse by trapping allergens on the eye. The objective of this post hoc analysis was to address this question and thus assess the effect of punctal occlusion alone on ocular itching and conjunctival redness associated with AC.

METHODS

This was a pooled post hoc analysis of three randomized, double-blind, placebo insert-controlled clinical trials in subjects with AC. Enrolled subjects were generally healthy adults with ocular allergies and a positive skin test reaction to perennial and/or seasonal allergens. The study used a modified version of the traditional conjunctival allergen challenge (CAC) model, which included multiple, repeated allergen challenges following placement of the intracanalicular insert. Subjects were rechallenged on Days 6, 7 and 8; Days 13, 14 and 15; and Days 26, 27 and 28.

RESULTS

The data set included 128 subjects that were administered placebo. Baseline mean (SD) ocular itching and conjunctival redness scores were 3.52 (0.44) and 2.97 (0.39), respectively. On post-insertion Days 7, 14 and 28, mean itching scores were 2.62, 2.26 and 1.91, respectively, representing 26%, 36% and 46% itching reductions, respectively (p < 0.001). On Days 7, 14 and 28, mean conjunctival redness scores were 1.98, 1.90, and 2.08, respectively, representing 33%, 36%, and 30% redness reductions, respectively (p < 0.001).

CONCLUSIONS

Based on this post hoc pooled analysis, punctal occlusion with a resorbable hydrogel intracanalicular insert did not worsen ocular itching or conjunctival redness in this patient population.

Retrospective Study of a Sustained-Release Intracanalicular Dexamethasone Insert for Treatment of Ocular Inflammation After Cataract and Corneal Surgery

PURPOSE

To evaluate the effectiveness and safety of a sustained-release intracanalicular dexamethasone insert (Dextenza, Ocular Therapeutix, Inc.) as an adjunctive therapy in patients undergoing cataract and corneal surgery.

PATIENTS AND METHODS

This retrospective case series contains 18 patients undergoing cataract surgery and 6 patients undergoing corneal surgery. All patients received the Dextenza intracanalicular insert. 6/18 of the patients in the cataract surgery arm were on the standard of care post-surgery topical steroid drop regimen, whereas 11/18 of the patients were on a reduced regimen. 1/18 of the patients was on a drop regimen that deviated from the aforementioned regimens. 2/6 of the patients in the corneal surgery arm were on the standard of care post-surgery topical steroid drop regimen, whereas 3/6 of the patients were on a reduced regimen. 1/6 of the patients were on a drop regimen that deviated from the aforementioned regimens.

RESULTS

The primary outcome measures are intraocular pressure (IOP) levels and anterior chamber inflammation levels across the post-operative recovery period. 1/18 of the patients in the cataract surgery arm and 1/6 of the patients in the corneal surgery arm experienced a clinically significant IOP spike greater than 10 millimeters of mercury (mmHg) above baseline IOP. No patient in either of the study groups had significant inflammation after 1 week post-surgery. 1/18 of the patients in the cataract surgery arm and 1/6 of the patients in the corneal surgery arm experienced a canalicular obstruction.

CONCLUSION

Dextenza with the lower drop protocol showed non-inferiority in terms of inflammation management and safety. As with any steroid delivery mechanism, monitoring IOP is paramount when using Dextenza. One of the patients with a canalicular obstruction had a history of punctal plug implantation, so care should be taken when choosing to implant Dextenza in such a patient.

Thermal Pulsation with or without Dexamethasone Intracanalicular Insert for Meibomian Gland Dysfunction: A Prospective, Masked Trial

Significance

Meibomian gland dysfunction (MGD) is among the most common causes of dry eye disease worldwide. Few studies have compared treatment options, and the basis for an evidentiary approach to MGD management is lacking. We have conducted a non-randomized trial evaluating the additive benefit of a recently developed therapy.

Purpose

To compare the efficacy of thermal pulsation therapy alone or combined with the dexamethasone intracanalicular insert (Dextenza) on the signs and symptoms of MGD.

Methods

This was a prospective, patient-masked, sham-controlled, non-randomized trial. All subjects underwent thermal pulsation therapy using the LipiFlow system. The dexamethasone intracanalicular insert was placed in the inferior canaliculus of the more symptomatic eye (DEX group), while sham punctal dilation of the fellow eye was performed to preserve patient masking (SHAM group). Key outcomes were improvement in meibum expressibility at 1, 4, and 12 weeks and patient treatment preference at week 12.

Results

Nineteen subjects underwent thermal pulsation therapy and received the DEX insert. Meibomian gland expressibility scores improved significantly in both groups at 1, 4, and 12 weeks, with significantly greater improvement in DEX eyes than SHAM eyes at 12 weeks (P=0.027). Improvement from baseline in TBUT was significant at all time points in DEX eyes and only at week 4 in SHAM eyes, with significantly greater improvement in DEX eyes over SHAM eyes at week 12 (P=0.028). Mean best-corrected visual acuity and intraocular pressure remained unchanged from baseline throughout follow-up in both groups, and no adverse events were noted. Combined therapy with DEX was preferred by 61% of subjects.

Conclusion

This study demonstrated a significant benefit of combining thermal pulsation therapy with the dexamethasone intracanalicular insert on signs of MGD including TBUT and meibomian gland expressibility score. Consequently, a majority of patients preferred combination therapy to thermal pulsation therapy alone.

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.

Plasma Pharmacokinetic Parameters of Dexamethasone Following Administration of a Dexamethasone Intracanalicular Insert in Healthy Adults

Purpose

Intracanalicular dexamethasone insert is a resorbable sustained-release polyethylene glycol-based hydrogel insert delivering a 0.4 mg tapered dose of dexamethasone for up to 30 days to the ocular surface. It is FDA-approved for treating inflammation and pain after ocular surgery. It has also been studied for ocular surface diseases such as allergic conjunctivitis. This study assessed the plasma pharmacokinetic (PK) parameters of dexamethasone following intracanalicular insertion.

Patients and Methods

Study subjects (N=16) were healthy adults. A dexamethasone insert was unilaterally placed into the canaliculus, and blood samples were obtained for analysis 1 hour prior to insertion and 1, 2, 4, 8, 16, 24 hours and 4, 8, 15, 22 and 29 days after insertion. Safety analyses included slit lamp and dilated fundus examinations, best corrected visual acuity, intraocular pressure (IOP) and adverse events (AEs).

Results

Plasma results were below the lower limit of quantitation (LLOQ) at all time points in five subjects (31.3%). Among subjects with quantifiable plasma concentrations, C_max was <1 ng/mL (range, 0.05 to 0.81 ng/mL), AUC_0-last ranged from 0.13 to 7.18 h∙ng/mL, and T_max ranged from 4.0 to 163.0 hours. Mean (SD) IOP increased from 16.3 (1.4) mmHg at baseline to 19.3 (3.2) at Day 22 but returned to baseline after treatment. No changes occurred in dilated fundus, punctum, or visual acuity examinations.

Conclusion

The dexamethasone 0.4 mg insert results in minimal systemic exposure following intracanalicular administration.

Design of the ocular coil, a new device for non-invasive drug delivery

Eye drops and ointments are the most prescribed methods for ocular drug delivery. However, due to low drug bioavailability, rapid drug elimination, and low patient compliance there is a need for improved ophthalmic drug delivery systems. This study provides insights into the design of a new drug delivery device that consists of an ocular coil filled with ketorolac loaded PMMA microspheres. Nine different ocular coils were created, ranging in wire diameter and coiled outer diameter. Based on its microsphere holding capacity and flexibility, one type of ocular coil was selected and used for further experiments. No escape of microspheres was observed after bending the ocular coil at curvature which reflect the in vivo situation in human upon positioning in the lower conjunctival sac. Shape behavior and tissue contact were investigated by computed tomography imaging after inserting the ocular coil in the lower conjunctival fornix of a human cadaver. Thanks to its high flexibility, the ocular coil bends along the circumference of the eye. Because of its location deep in the fornix, it appears unlikely that in vivo, the ocular coil will interfere with eye movements. In vitro drug release experiments demonstrate the potential of the ocular coil as sustained drug delivery device for the eye. We developed PMMA microspheres with a 26.5 ± 0.3 wt% ketorolac encapsulation efficiency. After 28 days, 69.9% ± 5.6% of the loaded ketorolac was released from the ocular coil when tested in an in vitro lacrimal system. In the first three days high released dose (48.7% ± 5.4%) was observed, followed by a more gradually release of ketorolac. Hence, the ocular coil seems a promising carrier for ophthalmic drugs delivery in the early postoperative time period.

Dexamethasone 0.4mg Sustained-Release Intracanalicular Insert in the Management of Ocular Inflammation and Pain Following Ophthalmic Surgery: Design, Development and Place in Therapy

Inflammation and pain are two prevalent findings after ocular surgery. Corticosteroids are widely administrated as a core treatment to control post-surgical inflammation and pain. Improper patient adherence to post-operative eye drop regimens, limited bioavailability of topical eye drops, and the negative impact of preservatives used in many of these eye drops, has made a strong case for novel therapies in the treatment of post-operative pain and inflammation. This review of the literature will focus on the role of intracanalicular sustained-release dexamethasone (Dextenza, Ocular Therapeutix, Bedford, MA, USA) for the management of ocular inflammation and pain.

Phase III trials examining the efficacy of cetirizine ophthalmic solution 0.24% compared to vehicle for the treatment of allergic conjunctivitis in the conjunctival allergen challenge model

Purpose

The purpose of these Phase III studies was to evaluate the efficacy and safety of cetirizine ophthalmic solution 0.24% compared with vehicle in the treatment of allergen-induced conjunctivitis using the Ora conjunctival allergen challenge (CAC)^® model.

Methods

The single-center (Study 1) and multi-center (Study 2), double-masked, randomized, vehicle-controlled, parallel group, CAC studies were conducted over ~5 weeks and four study visits. The study design only differed in entry criteria: Study 2 required more severe allergic conjunctivitis symptoms. Subjects were screened for an allergen response at Visits 1 and 2 and then randomized at Visit 3. Approximately 100 subjects were randomized in each study. The primary efficacy endpoints were ocular itching and conjunctival redness 15 minutes and 8 hours post-treatment, post-CAC.

Results

Cetirizine treatment administered 15 minutes or 8 hours prior to CAC resulted in significantly lower ocular itching at all time points post-CAC (P<0.0001) compared to vehicle in both studies. Conjunctival redness measured by the investigator was significantly lower after cetirizine treatment compared to vehicle at 7 minutes post-CAC at both 15 minutes and 8 hours post-treatment in both studies (P<0.05). All secondary endpoints were in favor and confirmatory of cetirizine efficacy with significant improvement in chemosis, eyelid swelling, tearing, ciliary redness, and episcleral redness, as well as nasal symptoms (rhinorrhea, nasal pruritus, ear or palatal pruritus, and nasal congestion) post-CAC. The most robust treatment differences were observed in Study 2 where more severe symptoms were required for study entry (P<0.05). No safety concerns for cetirizine ophthalmic solution 0.24% were identified.

Conclusion

Cetirizine ophthalmic solution 0.24% was shown to be efficacious in the treatment of ocular and nasal signs and symptoms associated with allergic conjunctivitis and demonstrated a favorable safety profile. Clinical efficacy was demonstrated with a 15-minute onset of action and añ8-hour duration of action.

Ocular translational science: A review of development steps and paths

Developing successful drug delivery methods is challenging for any tissue, and the eye is no exception. Translating initial concepts into advanced technologies treating diseases in preclinical models and finally into functional and marketable products for humans can be particularly daunting. While referring to specific ophthalmic companies and products, this review considers key exchanges that lead to successful translation. By building on basic science discoveries in the academic setting, applied science can perform proof-of-concept work with simple, benchtop experiments. Eventually, simple models need to be translated to more robust ones where cells, tissues, and entire organisms are incorporated. Successful translation also includes performing due diligence of the intellectual property, understanding the market needs, undertaking clinical development, meeting regulatory requirements, and eventually scale up manufacturing. Different stages of the translation can occur in different environments, including moving from academia to industry, from one company to another, or between veterinary and human applications. The translation process may also rely on contract organizations to move through the complex landscape. While the path to a commercial, marketable product may not look the same each time, it is important to design a development plan with clear goals and milestones to keep on track.