Updated from Aug. 27
ended lower Friday while a Food and Drug Administration advisory committee reviewed its experimental drug Macugen for the eye disease wet age-related macular degeneration.
Eyetech, a small, New York-based biotech, is collaborating with
, the world's largest drugmaker, whose stock was not halted.
In a brief statement late Friday, Eyetech said the panel has not taken a formal vote, "in accordance with the rolling submission process." The company provided no further information on the meeting, but said it and Pfizer were "pleased to have the opportunity to meet with the FDA and its advisory committee and look forward to further dialogue with the agency."
A favorable opinion by an FDA advisory committee doesn't guarantee approval by the full agency, but the FDA usually follows the advice of its advisors.
On Thursday, an FDA staff report took no formal stand on the drug, but it did recommend a series of questions that the advisory panel's members should address. Most importantly, it said the experts should determine if sufficient data have been submitted. It also says the panel should decide if additional analyses of current data are needed.
Eyetech eased $1.74, or 4.4%, to $37.46 when shares finally opened for trading late in Friday's session. Shares had jumped more than 11% Thursday in heavy volume -- about 12 times their daily average of about 574,000 shares.
Wet age-related macular degeneration distorts, diminishes and destroys eyesight. Tests of suggest greater hope in retarding the progress of a disease for which the few current treatments are often meager, expensive and impermanent.
As its name implies, the biggest cause of wet age-related macular degeneration (AMD)is advancing age. It is the "single leading cause of irreversible severe vision loss in developed countries," according to a presentation by Eyetech and Pfizer. This disease "remains an area of high unmet medical need and is a major public health issue in an aging population," the companies say.
The disease affects an estimated 1.6 million Americans and is growing at about 200,000 U.S. patients per year. (There is a dry form of the disease that affects more people but has less serious consequences.)
Eyetech and Pfizer are seeking FDA approval based on tests that show patients taking Macugen lose less vision to the disease than do patients receiving a placebo. The vision quality was measured by how many letters a person could detect on an eye chart.
The disease is caused by an overgrowth of new blood vessels in the macula, which is part of the retina and enables fine detailed vision. When these vessels leak blood or fluid, the macula bulges. That causes distorted vision and a decrease in central vision. In many cases, peripheral vision remains; but the blotting out of central vision can create legal blindness if the disease attacks both eyes.
Right now, patients have two choices for treating wet AMD. They can have their wet AMD treated with thermal lasers, which are fired into the eye, cauterizing the runaway blood vessels. But the lasers just halt the disease's progression, leaving a permanent blind spot where AMD has already done its damage. Lasers don't stop new blood vessels from developing.
The other treatment, which has been available for just over four years, works only for a fraction of wet AMD patients. This treatment involves the intravenous injection of Visudyne, a drug made by the Switzerland-based drug giant
and by the Canadian company
Visudyne chemically sensitizes the eye, which is then exposed to infrared light, also known as a cold laser. This therapy stops the unwanted blood vessels from leaking. It doesn't cause blind spots. Like the thermal laser; it doesn't restore lost vision and it doesn't stop the development of new blood vessels.
Called photodynamic therapy, this treatment is expensive, costing $4,000 to $8,000 a year, according to a report issued earlier this summer by Bear Stearns. Patients require treatment every three to four months, the report says. Only 20% to 25% of the wet AMD patients could be helped by this therapy.
The Eyetech-Pfizer approach tries to choke off the unwanted blood vessels before they can spread, leak and cause damage. Macugen inhibits the activity of vascular endothelial growth factor (VEGF), a protein that plays a key role in the development of new blood vessels.
One big drawback to Macugen is the fact that a doctor must inject it into a patient's eyeball every six weeks, causing some analysts and doctors to say that some elderly patients may avoid this treatment.
Eyetech maintains that such injections are "commonly used" and "generally accepted by patients facing the prospect of blindness and other serious back of the eye complications." However, a therapy that is less invasive "may have a competitive advantage," the company says in its 10-K report issued in March.
Eyetech and Pfizer say these injections were "well tolerated," adding that few patients dropped out of the tests. "No systemic safety issues were apparent," the companies say.
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