Cyclosporin Implant to Treat Uveitis

This study will evaluate the safety and effectiveness of a sustained-release cyclosporin implant to treat uveitis, a sight-threatening eye inflammation caused by an immune system abnormality. Previous studies in humans have shown that, taken by mouth, the drug cyclosporin is effective in treating chronic uveitis. Uveitis may require long-term treatment with potent immune-suppressing drugs, such as cyclosporin, cyclophosphamide, methotrexate, azathioprine or steroids. Taken systemically (by mouth or injection), however, these drugs can do serious damage to the kidneys, liver or lungs, and can raise blood pressure and lower blood cell counts. Because of this, some patients cannot or will not use these medicines. This small pilot study will evaluate the safety, and to some extent effectiveness, of cyclosporin delivered directly into the eye, to try to prevent harmful side effects. In animal studies, sustained-release cyclosporin implants did not cause the severe side effects seen with systemic use of the drug. Some animals developed opacity of the lens and slowed retinal responses, both of which reversed when the drug was stopped. Earlier animal studies of cyclosporin injected directly into the eye reduced inflammation that had been produced experimentally. Patients with uveitis who have active inflammation and poor vision are eligible to participate in this study. Patients will be randomly assigned to one of two treatment groups. One group will receive a 1-mg implant that releases 0.8 micrograms of drug each day; the second group will receive a 2-mg implant that delivers 1.4 micrograms of drug a day. Before surgery, patients will have a medical history, basic physical examination, and complete eye examination, including special tests called electroretinogram and fluorescein angiography. An electroretinogram measures the electrical responses generated in the retina in the back of the eye. Fluorescein angiography uses a special camera to photograph the retina, showi