LCD L38792: Dexamethasone Intracanalicular Ophthalmic Insert (Dextenza®)

Background :

Dextenza ® (Ocular Therapeutix, Inc., Bedford, MA, USA) is a resorbable hydrogel corticosteroid implant indicated for treating ocular inflammation and pain after ophthalmic surgery. After surgery, the insert is placed in the lower lacrimal punctum and into the canaliculus. The insert releases 0.4 mg of dexamethasone over 30 days onto the eye surface. It is made from a polyethylene glycol-based hydrogel conjugated with fluorescein, which is resorbable and does not require removal. Anterior chamber inflammation (10%) and elevated intraocular pressure (IOP) (6%) were the most common adverse reactions. IOP should be monitored during treatment. Dextenza ® should not be used in patients with active corneal, conjunctival, or canalicular infections, including epithelial herpes simplex keratitis (dendritic keratitis), vaccinia, varicella, mycobacterial infections, fungal eye diseases, and dacryocystitis.

Dextenza® is an alternative to topical corticosteroid preparations (e.g., eye drops) used to reduce pain and inflammation after cataract surgery. Persistent inflammation may lead to complications, such as increased IOP, cystoid macular edema, secondary glaucoma, delayed recovery, ocular pain, and reduced vision. However, patients may have difficulty delivering the correct dose when using topical eye drop preparations; eye drops may need to be tapered over time and are associated with poor patient adherence. 1 The elderly population, in particular, typically has more difficulty using eye drops to deliver topical corticosteroids after eye surgery.

Coverage Indications and limitations :

Palmetto GBA considers the use of the Dextenza® dexamethasone insert reasonable and necessary for the treatment of ocular inflammation and pain following ophthalmic surgery.

Dextenza® is contraindicated in patients with the following conditions:

• active corneal, conjunctival or canalicular infections, including epithelial herpes simplex keratitis (dendritic keratitis), vaccinia, varicella

• mycobacterial infections of the eye

• fungal diseases of the eye

• dacryocystitis.

An integrated assessment of Dextenza's® efficacy in ophthalmic surgery was demonstrated across 3 Phase 3 trials that included a total of 926 subjects (n=541, Dextenza®, n=385, placebo insert). 1-3 An ad hoc pooled analysis of the 3 Phase 3 studies demonstrated patients receiving Dextenza® achieved statistically, significantly superior outcomes compared to patients receiving placebo vehicle in both primary efficacy endpoints, with 42.7% of Dextenza®-treated patients observed to have absence of anterior chamber cells (score of 0) at Day 14 (placebo: 27.5%; P 1%) were increased (IOP), anterior chamber inflammation including iritis and iridocyclitis, eye inflammation, reduced visual acuity, corneal edema, and cystoid macular edema. There were no treatment-related serious adverse events. 1-3

Physician-administered Dextenza® delivers a 30-day tapered dose of dexamethasone to the eye (consistent with current standard of care tapered dosing regimen of patient-administered topical steroid drops). 1,2 Physician administration of Dextenza® avoids risk of improper patient installation techniques with post-op topical eye drop therapy, complicated steroid tapering dosing regimens for patient administration, manual dexterity challenges associated with older age, 5 and may reduce the potential for ophthalmic sequelae typically associated with poor patient adherence during the critical post-operative care period. Persistent ocular inflammation can potentially increase the risk for secondary ocular complications, such as increased IOP, cystoid macular edema (CME), posterior synechiae formation, posterior capsule opacification, secondary glaucoma, delayed recovery, ocular pain, and reduced visual outcomes, whereas untreated pain can affect overall patient surgical satisfaction. 6-8

Dexamethasone is a potent corticosteroid, and the Dextenza® Phase 3 data support the utility of a sustained-release intracanalicular insert delivery approach of dexamethasone to the ocular surface following ocular surgery. 1,2 Relevant to IOP increases associated with ophthalmic surgery, the overall safety outcomes of an ad hoc pooled analysis of the Phase 3 Dextenza® studies showed IOP elevation with Dextenza® (6.3%) compared to placebo (3.4%); 3 of all events, only 1 IOP increase in the dexamethasone insert arm (0.2%) out of 538 patients across 3 studies was considered by the investigator to be related to treatment. 1-3 It is hypothesized the observed rates of IOP increase demonstrated with Dextenza® compared to placebo in the Phase 3 studies may potentially be associated with the reduced Cmax of sustained release preparations (e.g., Dextenza®), as compared to topical steroid therapy. 1

Additionally, the benefits of consistent tapered dosing with a dexamethasone-eluting intracanalicular insert is potentially clinically meaningful in the context of the demonstrated poor bioavailability of topical steroid eye drop preparations. 9 The pharmacokinetic properties of the drug-eluting intracanalicular insert, in preclinical animal models, suggests sustained and tapered drug release into the tear film may minimize the potential of ocular rebound inflammation and demonstrate dexamethasone is eluted directionally and unilaterally towards the ocular surface, indicating limited systemic exposure and reduced wasted drug product. 10