Implant yields improvements in inflammation

Key Points

Irvine, CA-The pivotal study of a sustained-release dexamethasone intravitreal implant (Ozurdex, Allergan) showed that it was a safe, effective option for the treatment of noninfectious intermediate and posterior uveitis. In the study, a statistically significantly greater percentage of eyes randomly assigned to either of two doses of the implant met the primary outcome of a vitreous haze score of zero at week 8 compared with eyes that had undergone a sham procedure.

A single treatment with the implant gradually delivers dexamethasone to the posterior chamber, producing improvements in intraocular inflammation and visual acuity that, in this study, persisted for 6 months.

"If you just inject dexamethasone into the eye, it's usually gone within a day or two," said Scott Whitcup, MD, "so to get [a] sustained treatment effect you need a technology that allows you to deliver dexamethasone, in the case of [this intravitreal implant], for months."

In the 26-week, prospective, multicenter, masked, parallel-group, sham-controlled clinical trial, patients with noninfectious intermediate or posterior uveitis were randomly assigned to a single treatment with either a sham procedure (n = 76) or treatment with the 0.7-mg (n = 77) or 0.35-mg (n =76) dexamethasone implant. The primary outcome measure was based on the amount of vitreous haze and the proportion of patients with a vitreous haze score of zero at week 8.

Results showed that at week 8, 47% of the eyes treated with the 0.7-mg implant had a vitreous haze score of zero, as did 36% of the eyes treated with the 0.35-mg dose and 12% in the sham treatment group (p < 0.001).

"The other interesting finding was that not only did the inflammation go away, but patients gained vision," Dr. Whitcup said. "The fact that we saw such big improvements in vision was a big plus for patients."

Significantly more eyes in the implant groups than in the sham group had a gain of 15 or more letters from baseline best-corrected visual acuity at all study visits. The improvement was two- to six-fold greater in the implant groups, p < 0.001 for the 0.7-mg group and p ≤ 0.027 for the 0.35-mg treatment group. Up to 50% of patients gained three lines, with an average increase in visual acuity of about 12 letters.

Improvements in vision occurred more quickly than anticipated in these patients, as well as to a greater degree, Dr. Whitcup continued.

"In these patients, the inflammation was clearly affecting vision, and with resolution of the inflammation the vision also improved," he explained.