WASHINGTON, June 19 — The FDA has approved a novel, biodegradable, intravitreal implant system for treatment of macular edema following retinal vein occlusion, according to the developer, Allergan.

In a statement the company said dexamethasone intravitreal implant (Ozurdex) was the first drug therapy to win FDA approval for treatment of macular edema following branch retinal vein occlusion (BRVO) or central retinal vein occlusion (CRVO).

The drug is delivered via a polymer delivery system (Novadur), which was also developed by Allergan.

The combination of that delivery system with the biodegradable implant “enables the extended release and effect of dexamethasone. The implant is placed in the vitreous cavity in the back of the eye treating the macular edema associated with [retinal vein occlusion], thereby improving a patient’s visual acuity,” the company said.

The efficacy of the implant was assessed in two multicenter, double-blinded, randomized parallel studies involving approximately 1,300 patients.

In both studies patients randomized to the treatment drug had significant improvement in best-correct visual acuity compared with patients randomized to sham therapy (P < 0.01).

The implant will be administered as an in-office procedure, and the company said the treatment was expected to be available to physicians and patients in the U.S. in the third quarter of 2009.