Development of a dexamethasone intravitreal implant for the treatment of noninfectious posterior segment uveitis

Abstract

Uveitis is a group of ocular inflammatory disorders that can lead to severe vision loss. Despite advances in antiinflammatory therapy, many patients are resistant to or intolerant of existing treatments. A biodegradable, sustainedrelease implant, dexamethasone intravitreal implant 0.7 mg (Ozurdex), has been developed to deliver dexamethasone to target tissues in the posterior segment of the eye, minimizing systemic drug exposure and limiting side effects. The implant releases dexamethasone over a period of up to 6 months as the poly(d,l-lactide-co-glycolide) polymer matrix of the implant is metabolized to carbon dioxide and water. The implant is placed in the vitreous of the eye with a single-use applicator in a sutureless, office-based procedure. Treatment with a single dexamethasone intravitreal implant in patients with noninfectious intermediate or posterior uveitis has been shown to produce significant improvements in intraocular inflammation and best-corrected visual acuity with treatment benefit sustained for 6 months. Dexamethasone intravitreal implant has also been shown to reduce central retinal thickness and improve best-corrected visual acuity in patients with macular edema of various etiologies. The implant has been approved for treatment of noninfectious uveitis involving the posterior segment, diabetic macular edema, and macular edema associated with branch and central retinal vein occlusion.

Bimatoprost Sustained-Release Implants for Glaucoma Therapy: 6-Month Results From a Phase I/II Clinical Trial

“…26 In ophthalmology, an intravitreal implant employing the biodegradable NOVADUR platform used with Bimatoprost SR provides sustained release of dexamethasone and is approved by the US Food and Drug Administration for treatment of macular edema related to retinal vein occlusion, noninfectious posterior segment uveitis, and diabetic macular edema. 27 The implant contains micronized dexamethasone in a polylactic-co-glycolic acid copolymer matrix and has been on the market since 2009. The matrix slowly degrades to lactic acid and glycolic acid through hydrolysis, releasing dexamethasone into the vitreous for up to 6 months.…”

Calcium Phosphate as a Key Material for Socially Responsible Tissue Engineering

“…On the other hand, such strong binding usually does not stand in the way of a considerable amount of burst release that occurs in the first minutes of the contact of the material with the solution [ 25 ]. To promote sustained release of drugs from CAPs, such as that achievable using biodegradable polymers [ 26 , 27 , 28 ], thus stands as an enormous challenge.…”

Real-World Assessment of Dexamethasone Intravitreal Implant in DME: Findings of the Prospective, Multicenter REINFORCE Study

“…7 Effective intravitreal corticosteroid treatment of posterior segment disease requires use of a sustained-release delivery system to offset the short intravitreal half-life of corticosteroids. 8 Dexamethasone intravitreal implant (DEX) (Ozurdex; Allergan plc, Dublin, Ireland) provides sustained release of dexamethasone to the retina, thereby reducing the need for frequent injections. 9 In two large, multicenter, phase 3 trials (the MEAD study), a mean of four to five intravitreal injections of DEX 0.7 mg or Figure 1.…”