Summary of Research & Developments in
Macular Degeneration: 2007-2008
Omega-3 Proving to be Beneficial on Several Fronts
Recent studies have shown that Omega-3 fatty acids and fish consumption may reduce the risks of age-related macular degeneration (AMD), Alzheimer's disease, inflammation and depression.
The Age-Related Eye Disease Study (AREDS) Research Group showed that dietary total Omega-3 and docosahexaenic acid (DHA), a fatty acid, are beneficial to people with AMD. The study further verified what leading nutritionists have been saying for years: that several servings of the right kinds of fish per week are good for the retina.
Fish with the highest amount of Omega-3 are wild chinook or sockeye salmon, European anchovies, Atlantic/Pacific herring, small Atlantic/Pacific mackerel, black and red caviar, shrimp and Pacific sardines. Omega-3 can also be obtained from freshly-ground flaxseed or in stable, mercury-free fish oil supplements. Up to 200 mg of supplementary DHA is recommended for people who do not get enough fish in their diet.
Another study suggests that DHA may help prevent the accumulation of tau, a protein thought to be associated with brain lesions in Alzheimer's disease. Researchers from the University of California Irvine fed genetically modified mice different ratios of Omega-3 fatty acids, DHA and Omega-6 linoleic acid. Omega-6, which initiates the bodys beneficial inflammation response to disease or injury, is already plentiful in a normal diet, and too much of it can lead to uncontrolled inflammation--thought to be a major cause of AMD.
Mice that were fed a higher amount of Omega-3 and DHA than Omega-6, and mice that were fed only DHA, had lower levels of tau and a peptide called beta-amyloid (a constituent of amyloid plaques in the brains of Alzheimer's patients). The study also showed that DHA works better alone than in combination with Omega-6 fatty acids.
Some types of fish contain high amounts of Omega-6 and should, therefore, be avoided. Fish that contain dangerously high amounts are grouper, halibut, pompano, catfish, and Atlantic salmon.
Omega-3 also seems to help lower levels of depression. Researchers at Ohio State University in Columbus found that people who consumed much more Omega-6 than Omega-3 fatty acids reported more symptoms of depression.
All of these findings give further support to the current AREDS2 research, which is looking at adding Omega-3 fatty acid DHA to the original formula. Meanwhile, strong evidence suggests that it should be an integral part of everyone's diet, either through food or through supplementation.
(Some nutritional information in this article was provided by Ellen Troyer, MT, MA, Executive Vice President & Chief Research Officer, Biosyntrx.com.)
You May Need Vitamin D
If you are protecting your retinas by avoiding direct sunlight, you may also be depriving yourself of a natural source of vitamin D. This is the vitamin which allows your body to absorb enough calcium for strong bones. It is also important to protect us against muscle weakness and possibly a risk of breast, prostrate, and colon cancer.
In a Reader's Digest article ("Custom-Fit Vitamins," by Lisa Davis, November 2001), endocrynologist Michael Holick from Boston University recommended that adults expose their hands, arms, and faces to the sun for at least fifteen minutes three times a week. For people with macular degeneration, this would, of course, require wearing 100% UV protective sunglasses. If, however, this kind of exposure concerns you, then the alternative is to take at least 400 IU of vitamin D daily, which can be gotten from a multi-vitamin. If you are over 70, at least 600 IU is recommended, which means taking an additional supplement.
A paper published in the May 2007 issue of Archives of Ophthalmology confirmed that supplemental vitamin D may was inversely associated with early AMD, but only in individuals who did not consume milk daily. The researchers assessed 7,752 individuals, 11% of whom had AMD. They also found that levels of serum vitamin D were inversely associated with early AMD but not advanced AMD.
Good News For Chocolate Lovers, Cautionary Advice for Wine Drinkers
A report published in the December 2003 issue of Journal of Agricultural and Food Chemistry announced that cocoa has more antioxidant power that wine or tea. We have been told that red wine and green tea are beneficial for our retinas, but it looks like we should be drinking cocoa, too.
Cocoa has almost twice the antioxidant power of wine, 2-3 times that of green tea, and 4-5 times that of black tea. Scientist Chang Yong Lee headed up the study under the auspices of Cornell University in New York and Seoul National University in Korea. In an interview with a reporter for the AARP Bulletin (January 2004), Dr. Lee suggested a cup of hot chocolate in the morning, a cup of green tea in the afternoon, and a glass of red wine in the evening. This combination would satisfy our daily antioxidant requirement.
But remember: all things in moderation. Michael Holick (see above article) points out that people who drink more than two glasses of wine daily could be doubling their risk of colon cancer, and women who drink one or two glasses of wine daily may raise their chances of developing breast cancer by up to forty per cent. Since a glass of red wine daily has been shown to be beneficial to the retina, its negative effects may be lessened by an intake of 400 to 600 mcg of vitamin B (folic acid). This is the
equivalent of four to nine glasses of orange juice per day or two cups of boiled spinach, or it can be taken in a multivitamin.
Stem Cell Research Continues to Make News
In June 2007, Advanced Cell Technology announced successful production of a human embryonic stem cell line (hESC) without destroying an embryo. In 2006, ACT announced the development of the technique for harmlessly removing a single cell (a blastomere) from an eight-cell human embryo, and now they have succeeded in reality.
On January 7, 2007, researchers at the Institute for Regenerative Medicine at Wake Forest University School of Medicine discovered another potential source of embryonic stem cells in the amniotic fluid that protects babies in the womb. These cells appear to be almost as malleable as those in the embryo itself, and the advantage would be that harvesting them would not harm the embryo. Several more years of study are needed to assess their application in humans.
Other research is taking place in the United Kingdom at the University College London, Moorfields Eye Hospital and Sheffield University, in a cooperative effort called the London Project to Cure Blindness. Doctors at Moorfields have had some success with human subjects using adult stem cells from the patients' own eyes. Embryonic cells, however, have been shown to be more malleable and easier to transplant than adult stem cells. Laboratory-grown cells from the blastocyst of a 5-day old embryo require only one injection (a 45-minute procedure), whereas the Moorfields experiments have taken two hours and two surgical procedures. This protocol would be very expensive and impractical in general practice, so the researchers at the University of Sheffield are using embryos, which will take a little longer to get into human trials.
It is important to remember that stem cell transplantation is a treatment, not a cure. It is definitely promising, but if the cause of the disease is not eliminated, even replacement cells can eventually be affected. The cure will likely come from gene replacement, and that is a few more years down the road.
New Radiation Treatment for Wet AMD
NeoVista, Inc. announced on June 17, 2007 the official commencement of the CABERNET (Cnv secondary to Amd treated with BEta RadiatioN Epiretinal Therapy) clinical trial for the treatment of subfoveal choroidal neovascularization associated with wet AMD. The proprietary Epi-Rad90 Ophthalmic System, developed by NeoVista, is being utilized in the CABERNET clinical trial, including sites in the United States, Europe, Israel and South America. Learn more about the CABERNET trial at www. mdsupport.org/library/radiation2.html.
C3 Gene Variant Increases Risk of AMD
Researchers have found a gene variant that can more than double the risk of age-related macular degeneration (AMD).
The researchers based their findings on studies of 847 patients with who were compared with 701 unaffected people. They found that a variant in the complement C3 gene influenced the risk of developing AMD. For the 30% of the population who carry one copy of the so-called "fast" variant the risk of AMD was increased by 70%, and for the 4% of people with two copies of the "fast" variant the risk of AMD was more than doubled. The fast variant in the C3 gene increases the risk of both the wet and dry forms of the disease.
The complement C3 gene has a central role in the immune system. The results of this research provide strong evidence that inflammation is an important part of the disease process in AMD. This research was reported in the July 2007 New England Journal of Medicine.
Study Suggests Antioxidants May Not Prevent AMD Onset
A meta-analysis of published studies has found that vitamin A, vitamin C, vitamin E, zinc, lutein, zeaxanthin, beta carotene, beta
cryptoxanthin, and lycopene will not prevent the onset of early AMD.
The report, published in the October issue of the British Medical Journal concluded that "there is insufficient evidence to support the role of dietary antioxidants, including the use of dietary antioxidant supplements, for the primary prevention of early AMD." MD Support clarifies that this is referring to primary development of the disease, not slowing down of the progression of the disease once it has developed. The results of the Age-Related Eye Disease Study (AREDS) still stand: patients with advanced cases of dry AMD can moderately lower the risk of developing the more severe wet form of the disease and preserve vision by taking a daily dose of antioxidant vitamins and zinc.
In opposition to the conclusions of the meta-analysis, leading nutritionists argue that a discussion of disease prevention is much more complex than looking at the effect of a few antioxidants out of the entire spectrum of nutrients affecting the body's development and maintenance. We will hear more on this side of the issue from nutritionist Ellen Troyer at our next session.
Endostatin Joins List of Experimental Anti-Angiogenic Drugs for Wet AMD
Endostatin is an experimental drug derived from type XVIII collagen. It is currently being tested to stop cancer in people by restricting the formation of abnormal blood vessels supplying blood to tumors. Past research (J Folkman, 2006) has shown that it may restrict the formation of abnormal blood vessels by interfering with growth factor proteins such as vascular endothelial growth factor (VEGF). This now appears to be making it a likely treatment for wet AMD.
In the December 2007 issue of the journal of the Federation of American Societies for Experimental Biology (FASEB), researchers described how giving endostatin to mice significantly reduces or eliminates abnormal blood vessel growth within the eye.
As reported by Alexander Marneros et al, mice without normally-occuring endostatin were about three times more likely to develop advanced AMD than normal mice. When endostatin was administered to both sets of mice, those lacking endostatin showed a reduction in the number of abnormal blood vessels. In control mice with normal levels of endostatin, the number of abnormal blood vessels was practically undetectable.
Endostatin can now be added to the growing list of antiangiogenic drugs being studied as potentially effective treatments for wet AMD.
Stem Cells From Human SkinTwo research groups have described a method of creating induced pluripoint stem cells by inserting master regulator genes into the chromosomes of human skin cells. The altered cells appear to behave like embryonic stem cells, in that they might be capable of changing into any one of the 220 types of cells in the human body. This could eventually eliminate the need for using human embryos for research. The results were to be published in Cell by Shinya Yamanaka (Kyoto University and the Gladstone Institute of Cardiovascular Disease in San Francisco), and in Science by James A. Thomson et al (University of Wisconsin).
Four genes were used to reprogram the human skin cells, all of which act to turn other genes on or off, essentially reprogramming the cells into which they are introduced. A current drawback, however, is that one of the genes has a 20 percent risk of causing cancer. This means that, until the problem is solved, the stem cells created would not be suitable for replacement in people with degenerative cell diseases such as diabetes and macular degeneration. More study is needed, also, to determine if the reprogrammed cells are indeed the same as those from embryos. If that can be confirmed, destruction of embryos and donation of human eggs would no longer be necessary for ongoing stem cell research.
Stem Cell Success in RabbitsIn December 2007, Prof. Luis E. Abad, Head of Vitreoretinal Unit of COAT-vision, and Director of CERI, Murcia, Spain, announced the outcome of a study performed to demonstrate the changes resulting from implanting stem cells into eyes of rabbits with chorioretinal tissue injury induced by laser diode (Highlights of Ophthalmology, December 2007). A recovery of 90% of the injury was reported at the healing stage, as the transplanted cells survived and migrated toward the damaged areas of the retina and transformed into the rabbit's own epithelial cells.
Genentech and Physicians Reach Compromise on
In collaboration with the American Academy of Ophthalmology (AAO) and the American Society of Retina Specialists (ASRS), Genentech has provided an update on its efforts to address physician questions about access to Avastin after January 1, 2008. This is another positive outcome of Genentech's talks with the AAO and ASRS to understand physicians' concerns about the recent change in the delivery method of Avastin.
A compromise has been reached wherein physicians can now prescribe Avastin and purchase it directly from authorized wholesale distributors who can then ship to the destination of the physician's choice. This includes hospital pharmacies, compounding pharmacies or the physician's office. This process is one that the AAO and ASRS believe addresses the needs of their members.
Genentech continues to believe Lucentis is the most appropriate treatment for patients with wet AMD, because it was specifically designed, formally studied, approved by the FDA and manufactured specifically for treatment of the disease. Still, Genentech believes that physicians should be able to prescribe the treatment they believe is most appropriate for their patients.
The full update is posted on the Genentech website at www.gene.com/gene/features/avastin/press-statement.html.
VA Expands Low Vision Rehabilitation Training for Vets
More than 1 million visually impaired U.S. veterans over the age of 45 will soon have access to low vision rehabilitation training through a new program of the Veterans Administration.
In a press release issued December 9, Secretary of Veterans Affairs Jim Nicholson announced that the VA will make approximately $40 million available during the next three years to establish a comprehensive nationwide rehabilitation system for veterans and active duty personnel with visual impairments. The system will enhance inpatient services and expand outpatient services throughout the 1,400 locations where VA provides health care.
Under the reorganization plan, each of VA's 21 regional networks (called Veterans Integrated Service Networks, or VISNs) will implement a plan to provide eye care to veterans with visual impairments ranging from 20/70 to total blindness. Basic low-vision services will be available at all VA eye clinics, and every network will offer intermediate and advanced low-vision services, including a full spectrum of optical devices and electronic visual aids.
This improvement in care for visually impaired veterans is a big step forward. It is in line with the objectives of the optimum low vision rehabilitation delivery model approved in the fall by executive boards of all four professional eye care and rehabilitation academies. Read more about the model and how low vision rehabilitation can help visually impaired people maximize their vision and maintain their quality of life.
Cell Phone Text Reader
Here is a brand new idea for a portable text reader. It uses a cell phone to scan printed material and then read it aloud to you. The KNFB Reader software, expected to ship around February 15, will run on a Nokia N-82 phone. The reader is very small (4 ounces and a few inches long), and it is combined with features like an MP3 player, high-speed data connection and a GPS navigation system. The software will cost $1500, and the phone will run around $550. A press release on the topic may be found on the Internet at www.npr.org/templates/story/story.php?storyId=18504117. The official web page for the reader is at www.knfbreader.com/products-mobile.php
Cleveland Scientists Develop Mouse Model of AMD
The next time you see a mouse running across the floor, take a moment to thank his cousins for their contributions to science. The most recent example of rodent heroism combined with human intellect comes from the Cole Eye Institute in Cleveland, Ohio, where researchers have created the first animal model of age-related macular degeneration (AMD).
They did this by modifying specific proteins found in mouse blood, forcing the mouse's immune system to mount a response that led to the development of the characteristics of AMD. This historic development will help improve knowledge about the development and progression of the disease and will enable pre-clinical testing of new drugs for the dry form of AMD.
Research team leader Joe G. Hollyfield said this "presents a significant opportunity to efficiently and effectively develop and test novel therapies to both prevent the disease and slow vision
loss. Research conducted today may one day help find a cure for this progressive disease." The research was reported in the January 27, 2008 online edition of Nature Medicine.
Phase 3 Study Enrolling Patients
Regeneron Pharmaceuticals has announced that a phase 3 study, VIEW 1, is currently enrolling patients. The VIEW 1 study is comparing the VEGF Trap-Eye and Lucentis, an antiangiogenic agent approved for use in wet AMD. The VEGF Trap is a unique fusion protein that binds all forms of vascular endothelial growth factor-a (called VEGF-A) and placental growth factor (called PLGF). Both VEGF-A and PLGF are proteins that are involved in the abnormal growth of new blood vessels.
Patients interested in enrolling in the VIEW 1 trials should contact their physicians. Continuous updates about VEGF Trap-Eye and all other antiangiogenic drugs may be found in the MD Support Library at www.mdsupport.org/library/anti-angio.html.
New Anti-PDGF Aptamer Now in Trials
Ophthotech has begun the first phase of a clinical trial of E10030, an anti-platelet derived growth factor aptamer being developed for treating wet AMD. The trial will evaluate the safety and tolerability of E10030 in combination with an antiangiogenic drug. The hope is that the combination will result in regression of new unwanted blood vessels that have begun leaking into the retina due to neovascularization.
According to Samir Patel, M.D., president and CEO of Ophthotech, E10030 is the first of three compounds, including ARC1905 and volociximab (M200), that Ophthotech is developing to treat AMD.
CD36 Deficiency May Cause Dry AMD
CD36 is a protein molecule (called an "integral membrane protein") permanently attached to the surface of certain human cells. It plays a role in the inflammation process, but researchers
have now discovered that a deficiency of the protein may cause the dry form of macular degeneration.
Researchers reported that deficiency of CD36 in rodent models led to significant progressive age-related photoreceptor degeneration. They think this is caused by a resulting down-regulation of COX2, an enzyme that is important to blood vessel formation. Uncontrolled blood vessel growth (neovascularization) is a hazard to the retina, as in wet AMD. A decrease, however, in the normal size and number of choroidal vessels will starve the photoreceptor cells, causing the dry form of the disease.
This discovery may lead to a treatment for CD36 deficiency, which could have important implications for the development of new therapies for dry AMD. The research was published on February 19, 2008 in PLoS Medicine ("CD36 Deficiency Leads to Choroidal Involution via COX2 Down-Regulation in Rodents," Florian Sennlaub, et al, INSERM, Universite Pierre et Marie Curie, Paris).
CATT Research Beginning
On February 22, 2008 the National Eye Institute (NEI) of the National Institutes of Health (NIH) announced the start of a multicenter clinical trial ("Comparisons of Age-Related Macular Degeneration Treatments Trials") to study the relative safety and effectiveness of Lucentis (ranibizumab) and Avastin (bevacizumab). Both anti-angiogenic drugs are being used for treatment of wet AMD.
According to Paul A. Sieving, M.D., Ph.D., director of NEI, the 2-year CATT study "will evaluate whether the treatment burden for patients can be reduced without compromising effectiveness."
The trial will involve 1,200 patients, who will be treated with injections of either Lucentis or Avastin on a fixed schedule of once every four weeks for one year. In the second year, the patient will be assigned randomly to either an injection of the same drug every
four weeks or on a variable schedule depending upon response to treatment.
The primary outcome measure will be change in visual acuity. Secondary outcome measures will include number of treatments, anatomical changes in the retina, adverse events, and cost.
The trial will be conducted at 47 clinical centers across the country. For a list of centers, eligibility recruitments, and other information, see www.nei.nih.gov/CATT.
SAILOR Study Results Favorable
The final results from Cohort 1 of the Phase IIIb SAILOR study of Lucentis in patients with wet AMD were presented on February 23, 2008 at the Bascom Palmer Eye Institute's Angiogenesis meeting by Dr. David Boyer (Retina-Vitreous Associates Medical Group, Los Angeles). The final, one-year data support the long-term safety and efficacy profile of Lucentis.
The study was designed to evaluate the safety of two different doses of Lucentis (0.5 mg, the FDA-approved dose, and 0.3 mg) administered once a month for three months and thereafter as needed based on re-treatment criteria. The top line results were:
Rates of ocular and non-ocular serious adverse events at one year were similar in patients receiving either 0.3 mg or 0.5 mg of Lucentis and consistent with previous studies, supporting the long-term safety of Lucentis
Rates of ocular and non-ocular adverse events at one year were generally low in both dose groups and consistent with previous studies.
One-year results also demonstrated that the FDA-approved dose of Lucentis (0.5 mg) was not associated with the higher rate of stroke observed during the planned interim analysis at six months. The data suggested a trend towards a higher incidence of stroke in the 0.5 mg dose group (1.2% vs. 0.7% in the 0.3 mg group), though the results were not statistically significant.
At one-year, patients with a prior history of stroke had a higher rate of stroke in the 0.5 group (9.6%) compared to the 0.3 group (2.7%). However, this trend was inconclusive, as the number of events was small. These data are consistent with epidemiologic data showing that prior history of stroke predisposes patients to subsequent stroke.
One-year SAILOR efficacy data suggested that treating patients with Lucentis on an as needed basis may be less effective than monthly dosing.
Interleukin-8 Linked to Dry AMD
A report in the February 28, 2008 online British Journal of Ophthalmology revealed that at least some cases of age-related macular degeneration may stem from genetically driven production of interleukin-8. The gene variant is found more commonly in patients with age-related macular degeneration.
The -251AA genotype of the interleukin-8 promoter gene has previously been found to promote release of interleukin-8, an inflammatory cytokine. Cytokines are signaling compounds in the cells that are involved in a variety of immunological, inflammatory,and infectious diseases. This latest study has shown that the -251AA genotype is often found in people with AMD. Other inflammatory diseases, cancers, and even smoking behaviors have been linked to the gene, and it may also promote angiogenesis, as in wet AMD.
The results came from a case-control study involving 478 patients with macular degeneration and 555 people with healthy eyes. 35% of the patients and 27% of controls had the -251AA genotype. If follow-up studies confirm the findings, researchers
think it may be worthwhile to test patients for the -251AA genotype and treat them with anti-inflammatory therapies.
AMD Associated With Heart Attack and Stroke
Researchers at the University of Sydney have found that people suffering from AMD have twice the risk of dying from heart attack or stroke. 3,654 people aged 49 years old and older, were studied. Five years later, 2,335 people were re-examined, and after 10 years, 1,952 were re-examined.
When the study began, early AMD was linked with a doubling of their risk of dying from heart attack or stroke over the next 10 years. The risk increased fivefold in people with late-stage AMD, and their risk of dying from stroke increased 10 times.
A major reason for the association, according to experts, is probably increased vascular problems in aging adults caused by systemic inflammation. Recent studies have found genetic variances leading to excessive inflammation, which can cause cardiovascular disease and retinal dystrophy. At least three gene variances leading to inflammation have been found in people with AMD. These are C-reactive protein and LOC387115, plus a third gene variance causing overproduction of interleukin-8, an inflammatory cytokine also associated with cardiovascular disease.
As a result of these and similar studies, genetic screening may eventually lead to development of medications to treat the dry form of AMD.
Muller Cells May Restore Sight
Over the past several years, scientists have been taking an interest in certain cells within the patient's own eyes as having the potential to transform into stem-like (progenitor) cells. Called Muller glial cells, they would then migrate to damaged areas of the retina and replace dead cells, restoring vision lost to diseases like macular degeneration. Researchers at the Moorfields Eye Hospital in the U.K. have been studying the possibility of growing these cells in vitro and transplanting them back into the eye. For an abstract of their paper, see www.ncbi.nlm.nih.gov/pubmed/ 17525239.
Muller cells have long been known to be responsible for protecting and cleaning the retina of debris. Until now, however, it was not known what triggers their transformation into progenitor cells. On March 18, 2008, scientists at Schepens Eye Research Institute announced discovery of the chemical in the eye that is responsible. The discovery was published in the March issue of Investigative Ophthalmology and Visual Science (IOVS).
The research team, led by Dr. Dong Feng Chen (associate scientist at Schepens Eye Research Institute and Harvard Medical School) observed that the naturally occurring chemicals glutamate and aminoadipate (a derivative of glutamate) are the triggering mechanism. By injecting either of the chemicals into the eyes of healthy rats, they watched the Muller cells develop into new photoreceptors.
The next step is to test the process in animals affected by macular degeneration and retinitis pigmentosa in order to learn if vision will improve. Aminoadipate may be the chemical of choice, since it has fewer side effects than glutamate.
Robo-4 and Slit2 May Team Up Against Wet AMD
"Robo-4" sounds like a movie by Arnold Schwarzenegger, but in this case, it is a link to another potential treatment for wet AMD.
Short for "Roundabout," Robo-4 is a protein receptor found on the surface of blood vessel cells. When it binds with another protein called Slit2, the combination stops blood vessel growth (angiogenesis). This is a natural "braking" action on the normally beneficial process of healing. Blood vessels carry needed nutrition to unhealthy parts of the body, but their development must be kept under control.
If Robo-4 is deficient, the vascular endothelial growth factor (VEGF) that initiates angiogenesis will not be blocked. New vessels, therefore, will continue to grow unabated, often leaking and causing damage. Injecting Slit2 into Robo-4 deficient rodents has been shown to inhibit VEGF activity.
These new findings were reported in the March 16, 2008 online edition of Nature Medicine. (Lead author: Dean Y. Li, M.D., Ph.D., H. A., University of Utah, Salt Lake City UT.)
There is a difference between this therapy and anti-angiogenic drugs currently in use. Instead of blocking VEGF, injection of Slit2 activates a signal to the cells to block the VEGF themselves. This new mechanism may prove to be effective alternative treatment for wet AMD. Years of study, however, lie ahead before it can be applied in practice to humans.
More Benefits of Omega-3
The benefits of omega-3 (EPA and DHA) fatty acid dietary supplements for maintaining vision are well-known, and more positive effects in related areas continue to be found. One recent discovery is that omega-3 may help with symptoms of depression, and another study links prenatal omega-3 to increased visual acuity and cognitive development in babies.
A double blind study published in the Australian and New Zealand Journal of Psychiatry compared omega-3 to fluoxetine (eg. Prozac) and a combination of the two. Sixty participants were given either 1000 mg EPA, 20 mg fluoxetine, or a combination for 8 weeks. Patients were analyzed every 2 weeks, and 48 patients who completed at least 4 weeks of the study were included in the results. Using the Hamilton Depression Rating Scale (HDRS), researchers found a decrease in baseline 50% in the fluoxetine, 56% in the EPA group and 81% in the combination group. EPA and fluoxetine combination, therefore, was concluded to be superior to either of the two alone.
Another study, published in the Journal of Pediatrics, has reported that omega-3 supplementation in the last months of pregnancy may increase cognitive and motor skills in infants. U.S.
and Canadian researchers tested 109 babies at six and 11 months of age, finding that their visual acuity and cognitive and motor development were closely linked to the level of DHA in umbilical cord blood at birth.
These findings further confirm the value of omega-3 in our diet.
CABERNET Trial May Expand to 30 Sites
On April 17, 2008, NeoVista, Inc. announced that the FDA has granted the company's request to expand the number of sites participating in its pivotal Phase 3 trial from 10 to 30 in the United States.
The CABERNET trial is designed to investigate the effect of low dose radiation combined with Lucentis for treatment of the wet form of AMD. According to NeoVista, the benefits of radiation therapy over drug therapy alone are that the treatment is effective over a longer term, it mitigates the inflammatory and fibrotic responses, it is minimally invasive, and it can be performed in a single out-patient treatment
Gene Therapy Breakthrough
According to two studies published in the New England Journal of Medicine*, doctors have, for the first time, used gene replacement therapy to restore vision in patients with Leber's congenital amaurosis. Leber's syndrome is a form of retinitis pigmentosa (RP) that affects children and often leads to blindness by age 30. Leaders of the studies were Albert Maguire, M.D., of the University of Pennsylvania School of Medicine and Robin R. Ali, Ph.D., of University College London.
Both research teams injected adeno-associated viruses into the subretinal space to deliver the rpe65 gene to the cells. One eye of each patient was treated.
In the U.S. study, one patient improved from an acuity of 20/2000 to 20/710. The three British patients didn't show acuity
improvement, but did improve in other areas of visual function. More sensitive night vision was reported for patients in both studies. No serious side effects or safety concerns were reported by either group. The next step is to study the treatment in younger patients.
According to Gordon Gund, chairman and co-founder of the Foundation Fighting Blindness (sponsors of the US study), "This is great news for all people affected by retinal degenerative diseases. The breakthrough paves the way for the development of gene therapies to treat a wide variety of retinal conditions including other forms of LCA, many forms of retinitis pigmentosa, Stargardt disease, Usher syndrome, and age-related macular degeneration."
*Effect of Gene Therapy on Visual Function in Leber's Congenital Amaurosis (James W.B. Bainbridge, Ph.D., et al, 10.1056/NEJMoa0802268, April 27, 2008)
Should Eye Pressure Be Checked After Lucentis Treatment?
One of our members recently asked us if her doctor should check her intraocular eye pressure (IOL) after every injection of Lucentis for wet AMD. Here is a response from one of our professional advisors, K. Bailey Freund, M.D.:
In most cases we no longer perform routine IOP checks after Lucentis or Avastin. The volume of these injections is 0.05ml, which is less than the 0.09ml (Macugen) & 0.10ml (Kenalog) injection volumes. The lower volume does not cause as much of an IOP spike. We have performed thousands of injections without IOP issues. In fact, some of the current study protocols do not require post-injection IOP checks. If a patient has an elevated IOP prior to the injection or the patient has advanced glaucoma, we may check IOP after the injection in these cases."
From Dr. Freunds reply, it appears that pressure checks are not considered as important now that the physicians have gained more clinical experience. Genentech, Inc., maker of Lucentis, continues to recommend the procedure in their published protocol, but it is evidently not as commonly done in practice as in the past. This is good for us to know as we continue to educate ourselves about our treatment and care.
Statins and AMD
What effect do cholesterol-lowering drugs have on the retina? A pilot study in 2006 found "that treatment with simvastatin increased blood-flow velocity in the retinal arteries and veins and decreased intraocular pressure. (Nagaoka T et al. Arch Ophthalmol 2006; 124:665-670.)
This study supports the thinking that increased blood flow is generally beneficial to the retina. Recent research, however, has shown that taking statins to lower cholesterol levels might hasten the onset of wet AMD in people who are already affected by the dry form. The abstract for this study may be read on the Web at www.tinyurl.com/5ksj6a.
Considering the proven beneficial effects of drugs like simvastatin for people with circulatory problems and high cholesterol, it would be wise to keep this information in mind, but it would not be wise to stop taking them altogether without professional consultation. Until researchers have sorted out the facts, a patient's decision should be based upon individual circumstances and discussed with professional care providers.
More details about cholesterol research as related to AMD may be found in the MD Support Library at www.mdsupport.org/ library/cholesterol.html.
U.S. Currency Design Violates the Law
On May 20, 2008, the U.S. Court of Appeals for the District of Columbia Circuit upheld a 2006 district court ruling that could force the United States to redesign its money so visually impaired people can distinguish between values.
Judge Judith Rogers wrote that Treasury Department's current designs violate the Rehabilitation Act's guarantee of "meaningful access."
The Treasury Department has been working to improve the nation's paper currency, and is currently looking at different methods to help the blind and visually impaired.
The suit was originally filed in 2002 by the American Council of the Blind and two individuals with visual impairments, Patrick Sheehan and Otis Stephens.
Laser Rejuvenates the Retina
According to a study announced at the Euretina Congress in May 2008, a laser treatment that "cleans up" Bruch's membrane may slow down the progression to AMD.
Bruchs membrane is the tissue that separates the photoreceptor cells (our sight cells) from the nourishing blood vessel layer of the retina. It is through Bruchs membrane that the nourishment passes. As we age, however, the membrane can become clogged with debris, inhibiting the process and leading to cell malnutrition.
Research at St. Thomas's Hospital in London has resulted in development of a therapeutic approach to the problem. The Retinal Rejuvenation Therapy (2RT, Ellex) uses a special green nanosecond pulse laser for "reconditioning" Bruch's membrane and photo-regeneration. Improvement in visual function has been noted in humans during preliminary studies. Now, under the guidance of John Marshall, Ph.D., researchers are setting up a trial to treat the yet-unaffected second eyes of patients who have already lost vision in one eye due to neovascular problems.
The ultimate goal, said Dr. Marshall, is to treat patients in their 40s to keep their eyes young and prevent age-related degenerations of the retina. The treatment is noninvasive and seems to have no adverse effects on the photoreceptors or other parts of the eye.
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