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There are several reasons wet AMD has received so much more attention. Though fewer people have wet AMD, their vision loss is usually very fast and very bad. Dry AMD happens more slowly. According to Dr. Paul Sternberg, who presented at the meeting, doctors have had a limited knowledge of the causes and mechanisms of dry AMD.

He also noted that the slow progression of the disease makes clinical trials very expensive, since they would have to involve many more patients over a much longer period of time in order to study the progression. The causes or wet AMD are more obvious, which leads to more obvious treatment approaches. “The blood vessels are the problem, so let’s fix them.”

Now that the causes of dry AMD are better understood, researchers can work on finding solutions to them. We are seeing many more projects involving dry AMD now.

Othera Eye Drops (OT-551)

Dr. Paul Sternberg from Vanderbilt Eye Institute presented an overview of this exciting research aimed at developing an eye drop for macular degeneration. It is in a Phase II clinical trial of 198 patients with geographic atrophy (GA). GA is the advanced form of dry macular degeneration in which an entire area of cell death occurs. Using patients with GA makes sense because the geographic area can be measured easily. Geographic atrophy is also the greatest risk factor for advancing from dry AMD to wet AMD.

The reason this eye drop may work is because it is such a small molecule it can penetrate the cornea, the clear front part of the eye, and get into the vitreous, the gel that fills the eyeball. Once it is in the vitreous, it reaches the retina. Within 15 minutes, the drug is at the retina in a measurable quantity and it is active up to 16 hours. Patients in this study are using the eye drop four times a day, which maintains the amount of drug throughout 24 hours.

OT-551 is antioxidant, anti-inflammatory and anti angiogenic. It protects the retina from oxidative damage from sunlight, reduces swelling and works against the growth of blood vessels.

Called “OMEGA”, the study compares safety and efficacy of OT-551 with a placebo eye drop. Over two years, researchers seek to learn if the drop does reduce progression of area of GA. An interim report on the first 12 months of data will be released this spring.

What this means to you:

The prospect of using an eye drop for macular degeneration is encouraging. There is no treatment for dry AMD now and the treatments for wet AMD involve repeated eye injections.

This study is NOT recruiting any new patients. If the Phase II trial gives some promising results, a Phase III study would open to many more people with dry AMD and geographic atrophy. When that study opens, we will announce it so you could participate if you are eligible. Meanwhile, when the report on the first year's data is released, we will send it to you.

Implantable Miniature Telescope (IMT)

You may remember that the FDA did not approve this device when it was presented to them originally. They were concerned that the cornea of the eye was showing damage from the implantation of this miniature telescope.

The company is preparing a new submission that addresses this concern. If all goes well, they hope for approval within a year.

The IMT is a tiny magnifier implanted into the eye after cataract surgery. It goes into the space where a regular intraocular lens would normally be placed. The device magnifies the central vision. Some patients in the earlier study did achieve improved vision.

What this means to you:

The IMT is not currently available to anyone. If it is approved by the FDA, it would be a possible treatment to improve vision in people with macular degeneration.

Fenretinide Pill for Dry AMD

Dr. Lawrence J. Singerman reported on the early research for fenretinide, described the way it works and spoke about the Phase II clinical trial of patients with dry macular degeneration and geographic atrophy(GA).

One of the hallmarks of dry macular degeneration is the accumulation of cellular “debris”. The debris is also called “lipofuscin”. In a healthy eye, lipofuscin is reabsorbed and does not cause problems. In dry AMD, it shows up as drusen, those small deposits of proteins that appear on the retina. The debris is also present in the geographic atrophy that is the advanced form of dry macular degeneration.

The hope is that fenretinide will block the process that creates this lipofuscin and have a positive effect on drusen and geographic atrophy. Two hundred forty-five patients are part of this two year study. We should know the one year interim data in the first half of 2009. Followup is expected to be completed by Spring 2010.

What this means to you:

This is highly promising research with the hope of an oral treatment for dry macular degeneration. The Phase II clinical trial is closed and not recruiting any more patients. Once the data has been reviewed, a Phase III trial would be planned to include many more people. That means it will be several years before we know if this treatment will be available.

Retinal Cell Transplantation

Early reports are encouraging from a small study of patients with dry macular degeneration or retinitis pigmentosa. Seven of the 10 people in the study showed improved visual acuity.

The doctors implanted sheets of cells that included the retinal pigment epithelium (RPE) attached to neural (nerve) cells. The RPE is an essential layer of the retina, providing support to the photoreceptor cells. Photoreceptor cells gather in the light and transmit it to the brain. In patients with AMD and RP the photoreceptors die, but the rest of the vision pathway to the brain remains.

The intent of the surgery was to see if the new implanted cells would grow to replace the damaged photoreceptor cells and reconnect to the patient's remaining retina.

Because this was a Phase I clinical trial, they were also tracking the safety of the procedure, which was excellent, with no tissue rejection. The ability to develop this "sheet" of cells was another important result, as earlier attempts to transplant cells were not as successful.

Four people with dry AMD were part of the trial, along with six people with RP. All four AMD patients showed improved visual acuity and three of the RP patients improved. Remember that the patients entered the trial with vision in the "legally blind" range and even after these improvements, their vision could still be categorized as legally blind. One RP patient maintained the improved vision for six years following the surgery.

What this means to you:

This is a small clinical trial and this procedure is only available as part of a clinical trial. However, it is a very important study because of what researchers learned from it.

This is the kind of study that provides "proof of concept”. It gives everyone critical data and experience that lays the groundwork for continued work in this area. Along with others working in the field, they proved that the sheets of cells could be transplanted, could survive, would not be rejected; that the surgery was safe; that the new cells could grow and attach to existing retina. All this shows that more research could potentially provide greater improvements in vision.