Duke health brief

Tiny implant provides relief to patients with severe uveitis         

[JAN. 26, 2006]  DURHAM, N.C. -- Greater relief may be available for patients with severe uveitis, thanks to a tiny implant that's not much larger than a grain of rice. The implant, called Retisert, contains a tiny pellet of steroidal medication that, once placed in the eye, slowly delivers a powerful medication over a long period of time -- providing patients with relief for their condition and saving them both time and the side effects found with other therapies.

Patients with severe uveitis, an inflammatory eye disease, often experience pain, sensitivity to light, visual impairment and -- in the worst cases -- blindness.

"The implant makes a big difference in treatment because it allows us to give a very small, targeted dose of the medication directly where it needs to go, which is inside the eye," said Glenn Jaffe, M.D., an ophthalmologist and director of the uveitis program at Duke University Eye Center. "We no longer have to give a person large doses of medicine, which basically treat the entire body, in order to reach the eye."

The inflammatory disease is similar to arthritis, according to Jaffe, who led several clinical trials of Retisert. The medication in the implant is released slowly over a period of two to three years and works to alleviate inflammation. This time-released medication is expected to save the patient from having to take multiple doses of medication throughout the day and from enduring various shots of drugs directly to their eye area during times when the disease flares up.

"The whole idea of developing the implant is to provide a consistent delivery of medication that can quiet down the inflammation within the eye without causing side effects elsewhere in the body," said Jaffe. "We can potentially then get people off all the other medications they have needed for years, many of which cause significant side effects and are uncomfortable, making the patient fairly miserable."

Although not particularly common, the disease typically strikes people during their most productive years – between their 20s and 40s. Experts estimate that approximately 175,000 Americans have been diagnosed and roughly 800,000 people worldwide are living with the problem.

"For patients with the disease, it is very common for them to experience redness and pain in the eye, and bright lights can be bothersome," said Jaffe. "When uveitis occurs in the rear of the eye, as with the posterior form, it can cause visual impairments. This is particularly true when the inflammation is affecting the retina or the macula."

According to Jaffe, the posterior form of the disease can lead to macular edema, growth of abnormal blood vessels, the development of scar tissue, and occasionally a patient can experience blocked blood vessels in the retina, all of which are problems for the patient.

Effective treatments have been available, but they have significant side effects, Jaffe said. During periods of severe inflammation, patients sometimes need to take their medication every hour for about a week and then taper down for a period of several weeks until the inflammation has subsided. When that doesn't work, Jaffe points out, patients sometimes need to receive steroid injections around the eye, oftentimes along with oral medications.

Although use of the implant can eliminate the side effects caused by other medications, the Retisert may lead to the development of cataracts or increased intraocular pressure. But, Jaffe noted, those side effects can be managed effectively.

The goals in treating severe uveitis may be different from those for treating eye diseases like glaucoma or macular degeneration, he added.

"Preventing uveitis from getting worse is clearly one of the goals for treatment, but another goal is to keep their eye comfortable," Jaffe said. "In some cases this pain can be disabling, and the loss of vision can, not infrequently, be pretty profound. The goal of the treatment is to control the inflammation. If we can control the inflammation, the patient is more comfortable, and we have a much better chance of preserving or improving their vision."

Under local anesthesia, the implant is attached inside the eye with a suture. The implant itself is made of a material similar to what is used to create intraocular lens implants, and it does not dissolve along with the drug. Once the medication dissolves, the casing remains behind, but that doesn't pose a problem, said Jaffe.

"The ability to provide this new treatment option has really changed my uveitis clinic," he added. "We've gone from having a lot of unhappy people with chronic disease who didn't feel they had a lot of hope, to a clinic that is fun to go to because people are feeling really good for a change. And that's a big deal to them and to me."

[Duke University news release]