Implant benefits non-infectious posterior segment uveitis

Robert G. Devenyi, MD, the principal investigator of the international, multicenter, randomized, masked trial, reported the 34-week efficacy and safety results in Toronto.

A total of 239 patients (135 females and 104 males) were enrolled in the study in 19 centers in Canada, the United States, Australia, India, the Philippines, and Hong Kong. The mean patient age was 42.1 ± 13.4 years (range, 12.3 to 92.5 years). The patients were randomly assigned to receive either 0.59 mg or 2.1 mg of drug in the implant, according to Dr. Devenyi, ophthalmologist-in-chief and director of Retinal Services, University of Health Network, and professor of ophthalmology, University of Toronto, Canada.

In patients with unilateral uveitis, the affected eye received the implant; in patients who had bilateral disease the eye that was more severely affected was treated. In unilateral cases the fellow eye was not treated.

The mean baseline VA in the patient population was +0.60 ± 0.45 logMAR (20/80 Snellen). Before the device was implanted, most of the patients (166, 69.5%) had been receiving systemic therapy, and the remainder had been receiving local therapy.

"The aggregate results of the two doses at 34 weeks after implantation showed that the uveitis recurrence rate was statistically lower (p < 0.0001) in the eyes that received the Retisert implant (10.0%) compared with the recurrence rate in the fellow eyes without an implant (55.7%)," Dr. Devenyi reported. "There was also statistically signifi- cant improvement in VA (p < 0.05) in the eyes that received the implants, but there was no statistically significant change in the mean VA in the fellow eyes. Importantly, 20.9% of the eyes that received the implants had an improvement in the VA of three or more lines."

No eyes lost any lines of vision.

At the end of the 34 weeks, there was also a statistically significant decrease in the patients' use of various therapies: systemic corticosteroid therapy, immunosuppressant therapy, or both; periocular injections; and topical steroid eye drops to control inflammation in the eyes that received the Retisert implants, Dr. Devenyi said.

Managing side effects Progression of cataract and increases in IOP were the most commonly seen adverse effects associated with the treatment at the end of the 34-week study period. However, as Dr. Devenyi pointed out, these were expected based on the nature of the treatment, and they were managed with conventional approaches. Only one of the 239 patients required explantation, which was accomplished uneventfully.

The major advantage of the implantation of this device is the prolonged duration of time that the drug is in the eye, which, according to Dr. Devenyi, is thought to be 3 years of constant, linear release. Re-implantation of another device can be considered after 3 years.

"Each patient must be considered individually," Dr. Devenyi said.

"The Retisert implant has truly been life-changing for these patients with severe uveitis," Dr. Devenyi concluded. "Their need for very toxic, systemic medications has been obviated. Future studies will look at the efficacy of this implant with other ocular diseases."