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Complications of Age-Related Macular Degeneration Prevention Trial (CAPT)

Purpose | Background | Description | Patient Eligibility | Recruitment Status | Current Status | Results | Publications | Resource Centers | NEI Representative


To determine whether application of low-intensity laser treatment of eyes with drusen in the macula can prevent later complications of age-related macular degeneration and thereby preserve visual function.


Complications of age-related macular degeneration (AMD) are the leading cause of severe vision loss among people aged 65 and over in the United States and many Western countries. Most, (approximately 90 percent), of this vision loss is due to the neovascular (or wet) form of AMD. The word neovascular describes the development of new, abnormal blood vessels in the back of the eye. Unfortunately, the majority of these new vessels are not amenable to currently available treatments.

The first sign that an eye may develop AMD is the presence of drusen, yellowish deposits under the retina. Current data suggests that eyes with large drusen are at increased risk for developing the vision threatening complications of AMD. Since the 1970s investigators have reported consistently that laser photocoagulation causes a reduction in large drusen. However, results of the effects of laser treatment on preventing later complications of AMD have been less consistent and based on relatively small numbers of patients.

Further study into the ability of a treatment to prevent vision loss from the advanced forms of AMD would have profound public health implications. A treatment that could reduce the risk of developing neovascularization by 30 percent might reduce the risk of blindness from AMD by one half. The Complications of Age-related Macular Degeneration Prevention Trial (CAPT) will assess whether treating drusen by laser photocoagulation reduces the risk of loss of visual acuity.


The CAPT is a multi-center, prospective, randomized clinical trial designed to assess the safety and effectiveness of low-intensity laser treatment in preventing vision loss among patients with large drusen in both eyes. Eligible patients will have one eye randomly assigned to laser treatment performed by a CAPT-certified ophthalmologist. The other eye is not treated. Both eyes are observed carefully for any changes for a period of five years. The effectiveness of the treatment will be assessed using the following criteria:

Quality of life assessments for patients, using the Visual Function Questionnaire 25 (VFQ-25), will be conducted at the time of enrollment and at 5 years.

Patient Eligibility

Patients eligible for CAPT can be either male or female and meet the following criteria:

Final eligibility is determined through a detailed eye examination by a CAPT-certified ophthalmologist.

Patient Recruitment Status

Completed. A total of 1,052 have been enrolled at 22 clinical centers across the United States. Recruitment began on May 1, 1999 and ended on March 31, 2001. A minimum of 5 years of follow-up for all patients is planned.

Current Status of Study






Resource Centers

Chairman's Office
Stuart L. Fine, M.D.
Scheie Eye Institute
The University of Pennsylvania School of Medicine
Department of Ophthalmology
51 N. 39th Street
Philadelphia, PA 19104
Telephone: (215) 662-8142

Coordinating Center
Maureen G. Maguire, Ph.D., Director
CAPT Coordinating Center
3535 Market Street, Suite 700
Philadelphia, PA 19104-3309
Telephone: (215) 615-1500
Fax: (215) 615-1531

Photograph Reading Center
Judy Alexander, Director
CAPT Photograph Reading Center
3535 Market Street, Suite 700
Philadelphia, PA 19104-3309
Telephone: (215) 615-1515
Fax: (215) 615-1533

NEI Representative

Natalie Kurinij, Ph.D.
National Eye Institute
National Institutes of Health
Executive Plaza South, Suite 350
6120 Executive Boulevard, MSC 7164
Bethesda, MD 20892-5983
Telephone: (301) 496-5983
Fax: (301) 402-0528

Data and Safety Monitoring Committee

Brian P. Conway, M.D.
University of Virginia School of Medicine
Charlottesville, VA

Aaron Kasoff, M.D.
Albany Eye Associates
Albany, NY

Christopher Leighton, Ed.D.
Institute for Christian and Jewish Studies
Baltimore, MD

Anne Lindblad, Ph.D.
Emmes Corporation
Potomac, MD

David Mazur, M.D.
National Naval Medical Center
Bethesda, MD

Daniel Seigel, Ph.D.
Cushing, ME

Ex Officio Members

Stuart L. Fine, M.D.
Scheie Eye Institute
University of Pennsylvania
Philadelphia, PA

Natalie Kurinij, Ph.D.
National Eye Institute
National Institutes of Health
Bethesda, MD

Maureen G. Maguire, Ph.D.
Scheie Eye Institute
University of Pennsylvania
Philadelphia, PA

Last Updated: 11/6/01

Department of Health and Human Services NIH, the National Institutes of Health