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Newswise, February 5, 2016-- Researchers at Massachusetts Eye
and Ear/Harvard Medical School and the University of Crete have conducted a
phase I/II clinical trial investigating the efficacy of statins
(cholesterol-lowering medications) for the treatment of patients with the dry
form of age-related macular degeneration (AMD) — the leading cause of blindness
in the developed world.
Although effective treatments are available for the wet form
of AMD, they are currently lacking for the more prevalent dry form. The researchers
found evidence that treatment with high-dose atorvastatin (80mg) is associated
with regression of lipid deposits and improvement in visual acuity, without
progression to advanced disease, in high-risk AMD patients.
Their findings were published in EBioMedicine—a
new online journal led by editors of the journals Cell andThe
Lancet—and not only further the connection between lipids, AMD and
atherosclerosis, but also present a potential therapy for some patients with
dry AMD.
“We found that intensive doses of statins carry the potential
for clearing up the lipid debris that can lead to vision impairment in a subset
of patients with macular degeneration,” said Joan W. Miller, M.D., the Henry
Willard Williams Professor and Chair of Ophthalmology at Harvard Medical School
and Chief of Ophthalmology at Massachusetts Eye and Ear and Massachusetts
General Hospital.
“We hope that this promising preliminary clinical trial will
be the foundation for an effective treatment for millions of patients afflicted
with AMD.”
Affecting more than 150 million patients worldwide, AMD is
associated with an accumulation of drusen (deposits of lipid and fatty
proteins) under the retina, and patients with AMD experience blurred vision or
blindness in the center of the visual field.
There are two forms of AMD: “wet” and “dry.” The wet form
accounts for approximately 15 percent of AMD cases and is treated using
therapies previously developed at Mass. Eye and Ear/Harvard Medical School. The
“dry” form is more common, accounting for approximately 85 percent of cases,
and effective therapies are currently lacking.
Ophthalmologists and vision researchers have long suspected
that there may be a connection between dry AMD and atherosclerosis. In dry AMD,
physicians often see soft, lipid-rich drusen in the outer retina, similar to
the build-up of lipid material in the inner walls of blood vessels in
atherosclerosis.
Statin use is widespread in middle-aged and older individuals,
who also have an increased risk of AMD; however, previous studies have shown
very little correlation between regular statin use and improvements in AMD. The
authors of the EBioMedicine paper hypothesized that, due to the heterogeneous
nature of the disease, patients with soft, lipid-rich drusen may respond better
to statins prescribed at higher dosages.
“Not all cases of dry AMD are the exactly the same, and our
findings suggest that if statins are going to help, they will be most effective
when prescribed at high dosages in patients with an accumulation of soft, lipid
material” said Demetrios Vavvas, M.D., Ph.D., a clinician scientist at Mass.
Eye and Ear and Co-Director of the Ocular Regenerative Medicine Institute at
Harvard Medical School.
“These data suggest that it may be possible to eventually have
a treatment that not only arrests the disease but also reverses its damage and
improves the visual acuity in some patients.”
Twenty-three patients with dry AMD marked by soft lipid
deposits in the outer retina were prescribed a high dose (80mg) of
atorvastatin, the generic name of the statin marketed as Lipitor® and several
generic equivalents. Of the 23 patients, 10 experienced an elimination of the
deposits under the retina and mild improvement in visual acuity.
Other techniques that have attempted to eliminate the deposits
have mostly failed with the disease continuing to progress to more advanced dry
AMD or a conversion to the wet form of AMD.
As the next step for this line of research, the investigators
plan to expand to a larger prospective multicenter trial to further investigate
the efficacy of the treatment in a larger sample of patients with dry AMD.
“This is a very accessible, FDA-approved drug that we have
tremendous experience with,” said Dr. Vavvas.
“Millions of patients take it for high cholesterol and heart
disease, and based on our early results, we believe it offers the potential to
halt progression of this disease, but possibly even to restore function in some
patients with dry AMD.”
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