DESCRIPTION (provided by applicant): Age-related macular degeneration (AMD) is the leading cause of blindness in the United States and most western countries. The Comparison of AMD Treatments Trials (CATT) is a large-scale (1200 patient), randomized clinical trial designed to evaluate the relative efficacy and safety of alternative treatments for the neovascular form of the disease that accounts for approximately 90% of blindness due to AMD. We now request funding to complete the clinical trial and to follow the patients through 5 years to obtain long-term data on safety and vision. The goal of the Coordinating Center is to contribute to the success of the CATT by providing study leadership, data management, data analysis, and communication, by facilitating the execution of the study protocol, and by coordinating the activities of the study group. The Coordinating Center provides expertise on design of multicenter clinical studies, implementation and maintenance of high quality data management systems, statistical analysis, and quality assurance in data management and clinical center performance. The specific aims of the Coordinating Center to fulfill this role are: 7 Work with the other members of the study group to further refine the study design; 7 Create and maintain the study database through design of data collection forms, data capture, data editing, and data management; Provide timely, regular reports concerning study progress and performance to the clinical sites, OCT Reading Center, Fundus Photograph Reading Center, Executive Committee and its subcommittees, and the Data and Safety Monitoring Committee; 7 Design and implement a full program of quality assurance activities, in conjunction with the Executive Committee; Provide interim and final statistical analysis of the accumulated data on primary and secondary outcomes, as well as ancillary studies; Contribute to and distribute support materials for all CATT meetings; Participate and lead in the preparation of scientific presentations and reports. 7 Administer subcontracts with CATT clinical centers; RELEVANCE (See instructions): Age-related macular degeneration (AMD) is the leading cause of blindness in the United States and most western countries. These studies of the relative effectiveness and safety of the two drugs under study will determine how patients with neovascular ("wet") AMD are treated in the future.