Skip to Content

VisionAware

Resources for Independent Living with Vision Loss

American Foundation for the Blind® | Reader's Digest Partners for Sight

VisionAware Blog

Tell us what you think about VisionAware

Track This Blog By E-mail

New European Research: Is the Argus II (the "Bionic Eye") Cost-Effective?

the Argus 2 system

A group of European researchers has undertaken an economic analysis of the Argus II Retinal Prosthesis System (also called the "artificial retina" or "bionic eye") to assess the cost-effectiveness of the Argus II compared to standard care for the treatment of retinitis pigmentosa (RP) in Eurozone countries.

To date, they have determined that the Argus II is cost-effective and provides quality-of-life health gains, based upon the projected life span of the Argus II, expected to be the lifetime of the user.

[Editor's note: The European Union (EU) is a political union, while the Eurozone consists of 17 EU member states (out of a total of 28) that use the Euro as official currency.]

The research, entitled The cost-effectiveness of the Argus II retinal prosthesis in retinitis pigmentosa patients, was published on April 14, 2014 in BMC Ophthalmology. BMC Ophthalmology is an open-access journal that publishes original peer-reviewed research in all aspects of the prevention, diagnosis, and management of eye disorders, as well as public health research and genetics.

The authors are Anil Vaidya, Elio Borgonovi, Rod S. Taylor, José-Alain Sahel, Stanislao Rizzo, Paulo Eduardo Stanga, Amit Kukreja, and Peter Walter, who represent the following EU-based institutions: Maastricht University, The Netherlands; Bocconi University, Milan, Italy; University of Exeter Medical School, Exeter, UK; Centre Hospitalier National d’Ophtalmologie, Paris, France; Santa Chiara Hospital, Pisa, Italy; Manchester Royal Eye Hospital and University of Manchester, Manchester, UK; Second Sight Medical Products, Lausanne, Switzerland; and RWTH Aachen University, Aachen, Germany.

About the Argus II Device

The Argus II, developed by Second Sight Medical Products, Inc., of Lausanne, Switzerland and Sylmar, California, has been approved to treat adults with severe to profound retinitis pigmentosa (RP). RP is a rare, inherited degenerative disease that damages light-sensitive cells in the retina, resulting in decreased vision at night or in low light; loss of side (peripheral) vision; and loss of central vision as the disease progresses. At present, there is no cure for RP.

The retina is the light-sensitive tissue that lines the inside surface of the eye. Cells in the retinal tissue convert incoming light into electrical impulses. These electrical impulses are carried by the optic nerve to the brain, which finally interprets them as visual images.

The Argus II is not a cure for RP; instead, it is intended to replace the function of the light-sensing cells that have been damaged and/or degraded by the disease.

The Argus II device consists of the following components:

  • a small video camera
  • a transmitter mounted on a pair of eyeglasses
  • a video processing unit (VPU)
  • an artificial retina (the implanted retinal prosthesis, which is an array of electrodes)

The video camera images are transformed into electronic data by the VPU that sends signals to a wireless receiver implanted in the eye (the retinal prosthesis electrodes). The electrodes allow the electronic signals to bypass the damaged retina and transmit directly to the brain, where they are interpreted as visual images.

The cost of the Argus II is approximately $150,000; additional fees include the implantation surgery and training to use the device. The Second Site website provides an illustrated system overview, including a video animation.

Some Background: Argus II Development in the United States

On February 14, 2013, Second Sight received approval from the U.S. Food and Drug Administration (FDA) for the Argus II.

In July 2013, Second Sight announced that the Argus II would be offered in 12 initial consultation and implantation centers in the United States: Ann Arbor, MI; Atlanta, GA; Baltimore, MD; Chicago, IL; Cleveland, OH; Dallas, TX; Durham, NC; Los Angeles, CA; Miami, FL; Nashville, TN; Philadelphia, PA; and San Francisco, CA.

On August 15, 2013, Second Sight announced that the Argus II was approved by the Centers for Medicare and Medicaid Services (CMS), beginning October 1, 2013.

Who Is Eligible for the Argus II?

The Argus II is implanted in a single eye, typically the worse-seeing eye. It is indicated for persons with severe to profound RP who meet the following criteria:

  • Age 25 or older
  • Have bare light or no light perception in both eyes: Bare light perception is the ability to perceive light, but not the direction from which the light is coming. If the person has no residual light perception, then evidence of intact inner layer retina function must be confirmed.
  • A previous history of useful form vision
  • Be aphakic or pseudophakic: Aphakic means that the eye is lacking its natural lens. Pseudophakic means that the eye has been fitted with an artificial lens implant (as in cataract surgery) to replace the missing or surgically removed natural lens.
  • If the person is phakic (i.e., has a natural lens or an artificial lens implant) prior to the Argus II implant surgery, the lens will be removed during the implant procedure.
  • Be willing and able to receive the recommended post-implant clinical follow-up, device fitting, and visual rehabilitation.

Argus II Clinical Trial Information

The Argus II clinical trial study group includes 11 locations throughout Europe, the United States, and Mexico. A two-patient pilot study was initiated in Mexico in 2006, followed by a 30-patient trial in Europe and the United States. Two ongoing clinical trials include the Argus® I Clinical Trial and the Argus® II Clinical Trial.

The following everyday activities were evaluated during clinical trials:

  • detecting the direction of motion
  • recognizing large letters, words, or sentences
  • detecting and identifying street curbs
  • walking on a sidewalk without stepping off
  • matching black, gray, and white socks
  • locating and touching a square on a white background
  • Results indicate that most participants were able to perform these activities better with the device than without it.

You can read more about the Argus II in real life at The Argus II: Fact or Science Fiction? A "Bionic Eye" Pioneer Tells Her Story at the VisionAware website.

More about the European/Eurozone Argus II Study

From The cost-effectiveness of the Argus II retinal prosthesis in retinitis pigmentosa patients, with the full text available as an open-source article:

Background: Argus II is the world's first ever-commercial implant intended to restore some vision in blind patients. The objective of this study was to assess the cost-effectiveness of the Argus® II Retinal Prosthesis System (Argus II) in retinitis pigmentosa (RP) patients.

Method: [A model] was developed to determine the cost-effectiveness of Argus II versus usual care in RP from the perspective of healthcare payer. A hypothetical cohort of 1,000 RP patients aged 46 years followed up over a (lifetime) 25-year time horizon. Health outcomes were expressed as quality adjusted life years (QALYs) and direct healthcare costs expressed in 2012 euros.

Results and Conclusion: This economic evaluation shows that Argus II is a cost-effective intervention compared to usual care of the RP patients.

Limitations: This study shares the general limitations of economic modeling. The analysis presented in this paper was based on the data from only 30 Argus II fitted patients followed up for 24 months. Data from increased numbers of Argus II fitted patients with longer follow-up in the coming years provides an opportunity to re-consolidate the results of our analysis.

Future research should estimate costs and elicit RP patients' preferences to determine the utility values in these patients at various visual acuity levels.

[Editor's note: "Utility value" refers to the user's assessment of the value of an investment (in this case, the Argus II), based on its anticipated performance.]

VisionAware will continue to report on Argus II developments as they become available.


Topic:
Retinitis Pigmentosa

Is It Possible to Predict Risk for Developing Macular Degeneration? A New Study Says Yes

retina with wet AMD

When a close relative is diagnosed with age-related macular degeneration (AMD), family members will often ask, "Will I get macular degeneration, too? What is the likelihood that this will happen to me? Is there any way to predict it?"

A research group, composed of members from the United States and Australia, has attempted to answer those questions, via the development of a clinical eye-specific prediction model for advanced AMD. The researchers used eight predictors—age, sex, education level, race, smoking status, and the presence of pigment abnormality, soft drusen, and maximum drusen size—to create and validate a macular risk scoring system (MRSS).

The Macular Risk Scoring System

The research, entitled A Risk Score for the Prediction of Advanced Age-Related Macular Degeneration: Development and Validation in 2 Prospective Cohorts, was published online ahead of print in the March 19, 2014 edition of Ophthalmology. Ophthalmology, the official journal of the American Academy of Ophthalmology, publishes original, peer-reviewed reports of research in ophthalmology, including treatment methods, the latest drug findings, and results of clinical trials.

The authors are Chung-Jung Chiu, Paul Mitchell, Ronald Klein, Barbara E. Klein, Min-Lee Chang, Gary Gensler, and Allen Taylor, who represent the following institutions: Tufts University, Boston, Massachusetts; the University of Sydney, Australia; University of Wisconsin School of Medicine and Public Health; and The EMMES Corporation, Rockville, Maryland.

About the Research

From Risk score system accurate in predicting macular degeneration risk in 2 Minute Medicine:

In this retrospective study [i.e., examining data and records that were collected in past studies], the authors created the macular risk scoring system (MRSS) to help clinicians in assessing how likely it is that patients may develop age-related macular degeneration (AMD).

Two large AMD data sets, the Age-Related Eye Disease Study (AREDS) and the Blue Mountains Eye Study (BMES), were utilized to identify crucial parameters for the study, and five demographic predictors (age, sex, education level, race, smoking status) and three ophthalmic predictors (presence of pigment abnormality, soft drusen, and maximum drusen size) were identified.

[Editor's note: Drusen are the hallmark of "dry" AMD. Drusen are small yellow deposits beneath the retina that are a buildup of waste materials, composed of cholesterol, protein, and fats. They are a risk factor for progressing to vision loss.]

This is the first risk scoring system that also uses incidence data to help predict risk up to 10 years in the future. The authors also provide specificity and sensitivity for various cutoffs, providing flexibility for users. Limitations are mostly based on the limitations of BMES and AREDS, which include limited number of AMD cases and a narrow study population, respectively.

Overall, the MRSS provides a valuable tool to assess whether patients are low or high-risk, allowing the physician to alter monitoring as needed.

About the Blue Mountains Eye Study (BMES)

The longitudinal Blue Mountains Eye Study (BMES), named after the Australian mountain range, is the first large population-based assessment of visual impairment and common eye diseases of a representative sample of older Australians. A longitudinal study follows, and gathers information about, the same individuals or group of people over an extended period of time – often many decades.

The ongoing BMES began in 1992-1993, with the recruitment of 3,654 people aged 50 and older. Follow-up exams were conducted in 1997-1999 (5-year), 2002 (10-year) and 2007-2009 (15-year). You can read more about the BMES at the University of Sydney's Centre for Vision Research.

About the Age-Related Eye Disease Study (AREDS)

The Original AREDS Trial

The original Age-Related Eye Disease Study (AREDS), launched in 1992, was a major clinical trial sponsored by the National Eye Institute to (a) learn more about the history of, and risk factors for, age-related macular degeneration (AMD) and cataract and (b) evaluate the effect of high doses of antioxidants and zinc on the progression of AMD and cataract.

The original AREDS trial involved 4,757 participants, age 55-80 at the time of enrollment. Of 4,203 surviving participants, 3,549 (about 84 percent) took part in the follow-up AREDS2 trial.

The Second AREDS Trial (AREDS2)

In May 2013, The National Eye Institute concluded the Age-Related Eye Disease Study 2, which tested several changes to the original AREDS formulation. The ongoing AREDS trials have produced a number of breakthrough discoveries, including last year's clarification of the role of supplements in preventing advanced AMD.

A Research Summary from Ophthalmology

From the article abstract:

Design: The Age-Related Eye Disease Study (AREDS) cohort followed up for eight years served as the training data set, and the Blue Mountains Eye Study (BMES) cohort followed up for 10 years served as the validation data set.

Participants: A total of 4,507 AREDS participants (contributing 1,185 affected vs. 6,992 unaffected eyes) and 2,169 BMES participants (contributing 69 affected vs. 3,694 unaffected eyes).

Methods: We used eight baseline predictors—age, sex, education level, race, smoking status, and presence of pigment abnormality, soft drusen, and maximum drusen size—to devise and validate a macular risk scoring system (MRSS). We assessed the performance of the MRSS by calculating sensitivity, specificity, and … c-index.

Results: The internally validated AREDS and the externally validated BMES suggested excellent performance of the MRSS. An application for the iPhone and iPad also was developed as a practical tool for the MRSS.

Conclusions: The MRSS was developed and validated to provide satisfactory accuracy and generalizability. It may be used to screen patients at risk of developing advanced AMD.

Additional Information


Topics:
Low Vision
Medical Updates
Macular Degeneration

Why Do Some People Not Respond to Eye Injections for Macular Degeneration?

British Journal of Ophthalmology logo

Although the advent of anti-VEGF therapy (explained below) has revolutionized the treatment of wet age-related macular degeneration (AMD), there are still a number of persons – although in the minority – who do not respond to treatment. It is these "non-responders" or "reduced responders" who continue to pose significant challenges to clinicians and researchers.

Recently, a team of Japanese researchers attempted to identify a number of factors that could (a) predict non-response to intravitreal [i.e., into the eye] injections of Lucentis for wet AMD and (b) establish criteria for non-responders in order to avoid inefficient treatment.

The study, entitled Predictive factors for non-response to intravitreal [i.e., injection into the eye] ranibizumab [i.e., Lucentis] treatment in age-related macular degeneration, has been published online ahead-of-print in the April 7, 2014 edition of the British Journal of Ophthalmology (BJO).

The authors are Misa Suzuki, Norihiro Nagai, Kanako Izumi-Nagai, Hajime Shinoda, Takashi Koto, Atsuro Uchida, Hiroshi Mochimaru, Kenya Yuki, Mariko Sasaki, Kazuo Tsubota, and Yoko Ozawa from the Department of Ophthalmology, Keio University School of Medicine, Tokyo, Japan.

About Wet Age-Related Macular Degeneration (AMD)

In wet, or exudative, macular degeneration (AMD), the choroid (a part of the eye containing blood vessels that nourish the retina) begins to sprout abnormal new blood vessels that develop into a cluster under the macula, called choroidal neovascularization (neo = new; vascular = blood vessels).

The macula is the part of the retina that provides the clearest central vision. Because these new blood vessels are abnormal, they tend to break, bleed, and leak fluid under the macula, causing it to lift up and pull away from its base. This damages the fragile photoreceptor cells, which sense and receive light, resulting in a rapid and severe loss of central vision.

Anti-Angiogenic Drugs and Anti-VEGF Treatments

Angiogenesis is a term used to describe the growth of new blood vessels and plays a crucial role in the normal development of body organs and tissue. Sometimes, however, excessive and abnormal blood vessel development can occur in diseases such as cancer (tumor growth) and AMD (retinal and macular bleeding).

Substances that stop the growth of these excessive blood vessels are called anti-angiogenic (anti=against; angio=vessel; genic=development), and anti-neovascular (anti=against; neo=new; vascular=blood vessels).

The focus of current anti-angiogenic drug treatments for wet AMD is to reduce the level of a particular protein (vascular endothelial growth factor, or VEGF) that stimulates abnormal blood vessel growth in the retina and macula; thus, these drugs are classified as anti-VEGF treatments and are administered by injection directly into the eye after the surface has been numbed.

At present, these anti-VEGF drugs (Lucentis, Avastin, and Eylea) require monthly injections or a pro re nata [meaning "as needed"] (PRN) regimen, with monthly controls and injections for recurrent or persistent macular bleeding.

More about the Study

From Report examines factors for non-response to AMD injections at Insidermedicine:

A new report published in the British Journal of Ophthalmology examines factors that may predict non-response to intravitreal injections for age-related macular degeneration.

Researchers studied 141 AMD patients who had received intravitreal injections with ranibizumab [Lucentis] for three months followed by pro re nata [meaning "as needed"] injections for nine months.

Results showed that initial fibrovascular pigment epithelial detachment and serous pigment epithelial detachment were linked with non-response, as was type 1 choroidal nevascularization as judged by fundus findings.

An Explanation of Terms

  • Pigment epithelial detachment: A pathological process in which the retinal pigment epithelium separates from the underlying Bruch's membrane
  • Retinal pigment epithelium: A specialized retinal tissue that plays a crucial role in maintaining the equilibrium of all retinal processes. It is the pigmented layer of the retina, containing the deepest cells of the retina.
  • Bruch's membrane: Innermost layer of the choroid, lying beneath the retinal pigment epithelium. The choroid is the part of the eye containing blood vessels that nourish the retina.
  • Fundus: The rear portion of the interior of the eyeball that the doctor sees when looking at the eye through an ophthalmoscope, an illuminated instrument for viewing the interior of the eye.
  • Type 1 choroidal neovascularization: Refers to new blood vessels that grow and multiply underneath the retinal pigment epithelium. Their growth sometimes causes the pigment epithelium to detach.
  • Fibrovascular pigment epithelial detachment: A form of type 1 choroidal neovascularization
  • Serous pigment epithelial detachment: Occurs when the retina detaches from the pigment epithelial layer due to inflammation, injury, or vascular abnormalities. "Serous" refers to fluid that accumulates in the space beneath the retina.

More from the British Journal of Ophthalmology

From the article abstract:

Methods: We reviewed the clinical records of 141 eyes in 141 AMD patients who received monthly [intravitreal Lucentis injections] for three months and thereafter pro re nata [i.e., "as needed"] injections for nine months as the first treatment for AMD.

Patients whose best corrected visual acuity worsened at month 12, and those with increased exudative [i.e., leaking fluid] fundus findings after [intravitreal Lucentis injections] or an increased central retinal thickness of more than 100 micrometers at month 12, were considered to be non-responders as judged by best-corrected visual acuity and fundus findings, respectively.

Results: 14.9% of eyes were non-responders as judged by best-corrected visual acuity, and 17.0% were non-responders as judged by fundus findings.

Initial fibrovascular pigment epithelial detachment and serous pigment epithelial detachment were associated with non-response as judged by best-corrected visual acuity.

Initial fibrovascular pigment epithelial detachment and type 1 choroidal neovascularization were associated with non-response, as judged by fundus findings.

Conclusions: Although most AMD responded to [intravitreal Lucentis injections] non-responders had initial clinical characteristics that might be informative for managing their treatment.

VisionAware will provide updates of this important research as they become available


Topics:
Low Vision
Medical Updates
Clinical Trials
Macular Degeneration

Meet the Discovery Eye Foundation and the Macular Degeneration Partnership

Discovery Eye Foundation logo

The Discovery Eye Foundation, headquartered in Los Angeles, California, has become an important ally of VisionAware.org, especially in the area of patient education for macular degeneration. The primary mission of the Discovery Eye Foundation is twofold:

Recently, the Discovery Eye Foundation launched the Discovery Eye Foundation blog, featuring information on eye disease, eye research, nutrition, low vision resources, technology, and healthy lifestyle choices. Staff writers and guest bloggers include leading ophthalmologists, optometrists, eye researchers, low vision specialists, nutritionists – and even me, who penned a post on a topic near and dear to all vision rehabilitation professionals: Low Vision: What to Do When "There's Nothing More That Can be Done".

Spotlight on Macular Degeneration Partnership at Discovery Eye Foundation

The mission of Macular Degeneration Partnership (MDP) is to employ a multi-faceted approach in both the treatment of the disease and the support of persons with age-related macular degeneration (AMD):

Macular Degeneration Partnership logo

We are dedicated to making sure that you and your family members have the best information available to you and all the tools you need to live well with AMD. We want you to know that there is hope and help.

People who are diagnosed with macular degeneration are often given the impression that they must simply accept vision loss and that there is nothing that can be done. Instead, you can actually do something, even if medicine cannot treat the disease. Our mission is to help you on that journey with information, resources and personal support.

Our mission is to provide comprehensive, easily understood, and up-to-the-minute information about macular degeneration for everyone who needs it.

We support ongoing research in macular degeneration to help find new treatments and a cure for this sight-robbing disease.

Through our efforts, we will continue to coordinate advocacy campaigns throughout the world. We will use all tools available to us - the internet, the telephone, public events, and printed materials.

The MDP website contains a wealth of helpful information, including What is AMD?, Living with AMD, AMD Research, an e-newsletter, an "Ask an Expert" contact form, and a toll-free "warm line" at 888-430-9898.

Says Executive Director Judith Delgado, "What sets us apart is the personal attention and dedication MDP provides. We tailor the information to people's individual needs, whether they are looking for a low vision center, need help understanding their treatment, are worried about a family member, or have questions about their vitamins. While we do not give medical advice, we do provide enough information to help people make their own decisions."

The Macular Degeneration Partnership E-Newsletter

The current MDP e-newsletter contains excellent information on potential resources for financial aid for AMD injections:

The standard treatment for wet macular degeneration involves repeated injections into the eye. These can be very expensive, especially for someone without a secondary insurance. Lucentis and Eylea cost around $2,000 per injection. The financial burden can be overwhelming.

The Patient Access Network (PAN) Foundation is dedicated to providing help and hope to underinsured patients who would otherwise be unable to afford high-cost specialty medications. PAN provides assistance through nearly 60 disease-specific programs designed to help patients being treated for certain cancers, rare diseases and chronic illnesses - such as age-related macular degeneration.

Since 2004, PAN has provided nearly $400 million in financial assistance to more than 200,000 patients. PAN's Age-Related Macular Degeneration Program provides qualifying patients with $4,000 per year to help afford the co-pays and coinsurance associated with their prescribed medications.

To qualify, patients must be insured and their insurance must cover the medication for which the patient seeks assistance, must reside and receive treatment in the United States, and must have a household income at or below 500% of the Federal Poverty Level ($78,650 for a family of two). For more information, visit their website or call 1-866-316-7263.

Both Genentech (Lucentis) and Regeneron (Eylea) also fund patient assistance programs. For Lucentis, it is the Patient Access Program. For Eylea, it is Eylea4U. Your doctor will need to fill out an enrollment form.

Support Groups at Macular Degeneration Partnership

MDP also sponsors monthly peer support groups in the Los Angeles area:

  • Huntington Beach: Second Monday of each month, 12:30-2:00 in the Michael E. Rodgers Seniors Center, 1706 Orange Avenue, Huntington Beach, CA 92648
  • Santa Monica: Second Tuesday of each month, 1:00-2:30 in the Santa Monica YMCA, Santa Monica, CA 90401
  • Beverly Hills: Fourth Wednesday of each month, 1:00-2:30 in the Beverly Hills Library, second floor conference room, 444 N. Rexford Drive, Beverly Hills, CA 90210

Contact Macular Degeneration Partnership

Macular Degeneration Partnership
6222 Wilshire Boulevard, Suite 260
Los Angeles, CA 90048
310-623-4466
888-430-9898 (toll free)
E-mail: ContactUs@AMD.org.

Where you can find the Discovery Eye Foundation online:

Where you can find Macular Degeneration Partnership online:

Additional Information about Macular Degeneration


Topics:
Low Vision
Macular Degeneration
Lucentis
Eylea

A Potential Intravenous Treatment for Wet Age-Related Macular Degeneration: Interleukin-18

Translational Medicine logo

A research group, composed of members from the Republic of Ireland, the United Kingdom, and the United States, has determined that a protein called interleukin-18 (IL-18), which is a component of the immune system linked to inflammatory disorders, has the ability to suppress production of the harmful bleeding/leaking blood vessels that characterize wet age-related macular degeneration (AMD).

In addition, the researchers have demonstrated that IL-18 can be administered intravenously, which, if proven successful in human clinical trials, could offer advantages over the current treatment model, which requires injection of Lucentis, Avastin, or Eylea directly into the eye.

Please note: This "proof-of-concept" research is in its earliest stages and has been conducted only in pre-clinical settings with laboratory mice. Nevertheless, the concept shows promise for persons with wet AMD.

Interleukin-18

The research, entitled IL-18 Attenuates [i.e., weakens or reduces] Experimental Choroidal Neovascularization as a Potential Therapy for Wet Age-Related Macular Degeneration (explained below), was published in the April 2, 2014 issue of Science Translational Medicine.

Science Translational Medicine is an interdisciplinary medical journal, established in October 2009 by the American Association for the Advancement of Science, that covers basic, translational, and clinical research on human diseases. Translational research helps to make findings from basic science useful for practical applications that enhance human health and well-being.

The authors are Sarah L. Doyle, Ema Ozaki, Kiva Brennan, Marian M. Humphries, Kelly Mulfaul, James Keaney, Paul F. Kenna, Arvydas Maminishkis, Anna-Sophia Kiang, Sean P. Saunders, Emily Hams, Ed C. Lavelle, Clair Gardiner, Padraic G. Fallon, Peter Adamson, Peter Humphries, and Matthew Campbell, who represent the following institutions: Trinity College Dublin, Ireland; Our Lady's Children's Hospital, Dublin; Royal Victoria Eye and Ear Hospital, Dublin; National Eye Institute, Bethesda, Maryland; and GlaxoSmithKline, UK.

Wet Macular Degeneration

In wet, or exudative, macular degeneration (AMD), the choroid (a part of the eye containing blood vessels that nourish the retina) begins to sprout abnormal blood vessels that develop into a cluster under the macula (called choroidal neovascularization).

The macula is the part of the retina that provides the clearest central vision. Because these new blood vessels are abnormal, they tend to break, bleed, and leak fluid under the macula, causing it to lift up and pull away from its base. This damages the fragile photoreceptor cells, which sense and receive light, resulting in a rapid and severe loss of central vision.

Current Treatments for Wet Macular Degeneration

Angiogenesis is a term used to describe the growth of new blood vessels and plays a crucial role in the normal development of body organs and tissue. Sometimes, however, excessive and abnormal blood vessel development can occur in diseases such as cancer (tumor growth) and AMD (retinal and macular bleeding).

Substances that stop the growth of these excessive blood vessels are called anti-angiogenic (anti=against; angio=vessel; genic=development), and anti-neovascular (anti=against; neo=new; vascular=blood vessels).

The focus of current treatments for wet AMD is to reduce the level of a particular protein (vascular endothelial growth factor, or VEGF) that stimulates abnormal blood vessel growth in the retina and macula; thus, these drugs are classified as anti-VEGF treatments. At present, these drugs (Lucentis, Avastin and Eylea) are administered by injection directly into the eye after the surface has been numbed.

In the case of this particular research, the study team has determined that IL-18 also inhibits VEGF production.

More about the Study

From Scientists make major breakthrough in age-related macular degeneration therapy in Medical Xpress News:

The scientists found that a component of the immune system, IL-18, acts as a guardian of eyesight by suppressing the production of damaging blood vessels behind the retina at the back of the eye. In addition, in pre-clinical models, it was shown that IL-18 can be administered in a non-invasive way, which could represent a major improvement on the current therapeutic options that are open to patients.

"We were initially concerned that IL-18 might cause damage to the sensitive cells of the retina, because it is typically linked to inflammation. But surprisingly we found that low doses had no adverse effects on the retina and yet still suppressed abnormal blood vessel growth," said Assistant Professor in Immunology at Trinity, Sarah Doyle.

Treatment options for wet AMD are currently limited to the end stages of the disease. Regular injections of antibodies must be made directly into the eye to mop up a problematic molecule termed VEGF. However, the Trinity scientists found that IL-18 directly inhibits VEGF production, and that it can work as effectively as the current treatment when administered via a non-invasive intravenous injection in pre-clinical settings.

From Science Translational Medicine

From the article abstract:

Age-related macular degeneration (AMD) is the most common form of central retinal blindness globally. Distinct processes of the innate immune system, specifically activation of the NLRP3 inflammasome, have been shown to play a central role in the development of both “dry” and neovascular ("wet") forms of the disease.

We show that the inflammatory cytokine interleukin-18 (IL-18) can regulate choroidal neovascularization formation in mice. We observed that … administration of … IL-18 has no effect on retinal pigment epithelial (RPE) cell viability, but that overexpression of pro–IL-18 or pro–IL-1ß alone can cause RPE cell swelling and subsequent atrophy, a process that can be inhibited by the promotion of autophagy.

[Editor's note: Autophagy, a basic biological and metabolic process, "self-eats" cellular components that are unnecessary or dysfunctional to the cell, such as those that can cause the degenerative retinal changes that accompany AMD.]

A direct comparison of local and systemic administration of … IL-18 with current anti-VEGF (vascular endothelial growth factor)–based therapeutic strategies shows that IL-18 treatment works effectively alone and more effectively in combination with anti-VEGF therapy and represents a novel therapeutic strategy for the treatment of wet AMD.

VisionAware will provide updates of this research as it moves from the laboratory into human subject testing.

Additional Information


Topics:
Low Vision
Medical Updates
Macular Degeneration
Lucentis
Avastin
Eylea

Follow Us:

services icon Browse Archive

Join Our Mission

Help us expand our resources for people with vision loss.