Research News

New treatments macular disease, including ARMD, under investigation at UIC

Lawrence J. Ulanski, MD heads four clinical trials for the treatment of macular edema and age-related macular degeneration (ARMD).

Both diseases damage the macula, located at the center of the retina and which is responsible for fine, detailed central vision. Macular edema is often associated with diabetes, and causes swelling of the macula and reduced vision because of fluid or protein deposits leaking from fine blood vessels. In dry ARMD light-sensitive cells in the macula slowly break down and degenerate. ARMD is the most common cause of vision loss in the United States in patients aged 65 or older. In both diseases, wavy, blurred or distorted vision is the prevalent symptom.

Dr. Ulanski just completed a study sponsored by Occulogix, Inc. which evaluated the effects of rheophoresis, a novel blood filtration technique for dry macular degeneration. He is also beginning enrollment in a new study called AREDS2 which continues the National Eye Institute Age Related Eye Disease Study.

Rheophoresis

Occulogix Inc. has developed a new blood filtration procedure called rheophoresis, under the trademark RHEO™. In ARMD, the hypothesis is that arteries which supply blood to the retina harden, depriving the retina of essential oxygen and vital nutrients, and causing gradual weakening in vision. The rheophoresis procedure removes excess levels of macro-proteins, inflammatory factors and fatty components in the blood that have been associated with ARMD. Clinical trials suggest that the blood filtered with RHEO™ flows more easily through the tiniest capillaries in the body, including those of the macula, improving the delivery of oxygen and providing relief from ARMD. The MIRA-1 clinical trial found that patients who underwent the rheophoresis procedure had a statistically improved visual acuity compared to those patients who were treated by the normal standard of care. Further clinical trials of this novel procedure are underway.

AREDS II

UIC is participating in the second phase of a major National Eye Institute multi-center trial, The Age-Related Eye Diseases Study (AREDS) under Dr. Ulanski’s direction. The first phase, which ended in December 2005, investigated the use of high-dose antioxidants on ARMD. The study found that oral supplementation with high-dose antioxidant vitamins and minerals decreased the risk of developing advanced ARMD by 25%. After five years, patients on the regimen decreased by 19% their risk of moderate vision loss compared to placebo. AREDS II will clarify questions about vitamin dosages as well as the use of other supplements, such as lutein, zeaxanthin and omega-3 fatty acids, and the elimination of beta-carotene and the reduction of zinc levels from the original study regimen. This is a six year prospective study.

Macular Edema

Dr. Ulanski is researching novel drug delivery techniques that may enhance the effectiveness of existing drugs like dexamethasone in the Posurdex™ Drug Delivery System (DDS) to treat macular edema.

In the medical condition called retinal vein occlusion, the veins carrying blood out of the retina are blocked. As a result blood is not drained out of the retina efficiently. The retained blood may leak on to the retina, causing damage and impairing sight. When this leakage happens affecting the macula the condition is called macular edema.

Dr. Ulanski is working on improving the effectiveness of dexamethasone in treating macular edema. Dexamethasone is an FDA approved drug that is already used extensively to treat a variety of eye and systemic conditions. It reduces swelling and prevents redness. Currently, single injections of a less potent steroid called triamcinolone have been used successfully in treating macular edema. This technique has been effective; however, the single injection delivery only allows short term reduction in edema and must be repeated every two to three months.

The Porurdex™ DDS trial is a phase III FDA approval trial which aims to overcome the limitation of the single injection system by using an experimental drug delivery system that would gradually release dexamethasone into the eye. This technique is expected to release and sustain the required dosage of dexamethasone to improve the effectiveness of the drug in treating macular edema.

In addition to the Posurdex™ DDS being used for vein occlusions, a three year clinical trial for Posurdex™ to treat diabetic macular edema is also being conducted. This drug is inserted into the eye in a simple procedure in which the drug slowly breaks down and works gradually once in the eye. The drug insertion is an office based procedure, and is performed through a self-sealing wound. Posurdex™ has shown significantly better results in treating diabetic macular edema compared to current treatment techniques.

By Poornima Krishnan