The Anecortave Acetate Risk Reduction Trial (AART) recently completed enrollment of 2,596 patients worldwide. The study is being conducted in the United States, Europe, Australia, and South America. Sites have also been added in India and Singapore under a different protocol number. AART is investigating the ability of anecortave acetate 15 mg or 30 mg to prevent sight-threatening choroidal neovascularization (CNV) in high-risk eyes when compared with a sham procedure.
The AART study is the first of its kind in attempting to arrest CNV prior to the development of significant lesions. The primary efficacy measure for the study is the development of sight-threatening CNV, defined as CNV within 2,500 μm of the foveal center.1 Current treatments, and most treatments under investigation, are attempting to treat patients with an established diagnosis of CNV. However, after CNV is established the retinal photoreceptors can be permanently damaged, making the prospect of early prophylactic treatment the best option to preserve vision.
Patients enrolled in the AART study have had wet AMD diagnosed in one eye and have five or more intermediate (larger than 63 μm) or larger soft drusen and/or confluent drusen and hyperpigmentation, all within 3,000 μm of the foveal center in the contralateral eye (study eye). Patients with evidence of past or present CNV in the study eye were excluded.
In the AART study, anecortave acetate is delivered directly behind the macula by inserting a specially designed blunt-tipped, curved cannula along the surface of the sclera every 6 months for 4 years. Since it is administered without penetrating the globe, no clinically relevant safety issues have been identified thus far. It is an extraordinarily safe mechanism to deliver this medication and refinements in the posterior juxtascleral depot (PJD) procedure have improved drug delivery to the eye.
The AART study represents a significant step forward in the design and implementation of innovative clinical studies in AMD. Countless large epidemiologic studies have reported compelling information on the natural history of AMD, and specifically, fellow eye progression statistics.
For example, several studies have shown that patients with wet AMD in one eye are at high risk of developing CNV in the contralateral eye with dry AMD. It was found that patients with both large drusen (larger than 63 μm) and retinal pigment epithelial hyperpigmentation in the fellow eye faced a 58% risk of developing CNV within 5 years. By comparison, patients without large drusen or hyperpigmentation in their fellow eye faced a much lower (10%) risk of developing CNV.3
Another study found that if the fellow eye had five or more large drusen, it was more than twice as likely to develop CNV compared with a fellow eye with fewer or no drusen. The chance of CNV development also was found to be higher in eyes with confluent drusen and focal areas of hyperpigmentation. Among the 670 patients observed in this study, 236 (35%) developed CNV in the better eye within 5 years.4