Elderly people losing their vision from age-related macular degeneration might one day have a treatment option that requires fewer injections into the eye than the standard drug now used.
In testing, an experimental drug being developed by Regeneron Pharmaceuticals, when injected every eight weeks, proved as effective as the standard treatment, Lucentis from Genentech, which was injected every four weeks. The findings are from two clinical trials that Regeneron is expected to announce on Monday.
In a separate development, Advanced Cell Technology is expected to announce Monday that it has won regulatory approval to test a therapy derived from human embryonic stem cells in people with Stargardt’s macular dystrophy, another retina disease.
It is only the second trial of a therapy derived from human embryonic stem cells to be cleared by the Food and Drug Administration. The first involves a treatment for spinal cord injury developed by Geron.
Age-related macular degeneration is the leading cause of blindness in the elderly. Lucentis can restore a person’s ability to drive and read, in some cases.
But the drug works best when given every four weeks, which can be inconvenient for patients and doctors. Doctors often give Lucentis less frequently, but even if that regimen produces good results, patients must still get checkups every month to make sure their vision is not deteriorating.
Regeneron’s drug, which is called VEGF Trap-Eye, “gives us the opportunity to not have to see them monthly,” said Dr. Jeffrey Heier of Boston, an investigator in one of the trials and a consultant to Regeneron. That would be “very meaningful to patients and their families,” he said.
Regeneron and its partner, Bayer, said they planned to apply for approval of the drug in the first half of 2011.
The two similar trials involved a total of 2,457 patients who were randomly chosen to receive either Lucentis every four weeks or VEGF Trap-Eye either every four weeks or every eight weeks. In the eight-week arm, the first three doses were given every four weeks.
After a year, roughly 95 percent of the patients in all the arms of the trial maintained their vision, meaning their ability to read an eye chart declined by no more than 15 letters, or three lines.
VEGF Trap-Eye was also “noninferior” to Lucentis in terms of the average change in vision after one year. Lucentis recipients had a mean gain of 8.1 letters and 9.4 letters in the two trials. Those getting Regeneron’s drug every eight weeks had gains of 7.9 letters and 8.9 letters. Regeneron said the two drugs were equally safe.
Both VEGF Trap-Eye and Lucentis block a protein called vascular endothelial growth factor that causes blood vessels to grow and leak into the eye.
VEGF Trap-Eye could become the first big product for Regeneron, which was founded in 1988 and is based in Tarrytown, N.Y. It sells one drug for a rare disease and has garnered hundreds of millions of dollars from licensing deals with big pharmaceutical companies.
Regeneron’s drug is likely to face competition from off-label use of Genentech’s cancer drug Avastin. When used in the eye, Avastin costs about $50 a dose, compared with about $2,000 for Lucentis. Still, even with such low-priced competition, Lucentis has sales exceeding $2 billion globally.
Meanwhile, Advanced Cell Technology, of Marlborough, Mass., said it would test its stem cell therapy on 12 adults with severe vision loss caused by Stargardt’s, an inherited disease.
The company has turned human embryonic stem cells into retinal pigment epithelial cells, which will be surgically implanted into the eye. The hope is that the implanted cells will replace those injured by the disease.
Human embryonic stem cells are controversial because their creation usually entails the destruction of human embryos, although Advanced Cell Technology is working on a technique to avoid that.
Embryonic cells can also form tumors if injected into the body. Dr. Robert Lanza, chief scientist at Advanced Cell, said the company had to prove to the F.D.A. that its retinal cells contained virtually no residual embryonic stem cells. It took a year for the company to get clearance for the trial from the F.D.A.
It is likely to be several years before such a treatment can reach the market, if it works. Still, even starting the trial could be a boost to Advanced Cell, which often makes headlines but has struggled to raise money. Its shares closed at 5 cents on Friday.
Dr. Peter J. Francis, an associate professor at the Oregon Health and Science University, which will be a site for the trial, says the eye is a good place to test stem cell therapy because it is accessible. Also, he said, there is less chance of rejection of the implanted cells because the eye is shielded somewhat from the body’s immune system.
There is no treatment for Stargardt’s, which affects more than 25,000 people in the United States (and about 1 lakh people in India). The disease is usually diagnosed during childhood and it causes a loss of central vision, though not usually peripheral vision.
From the New York Times
Note from Retina India:
Retina India is creating registries or databases of patients with macular degeneration and Stargardt's disease. If you, or someone you know has the above diseases, or any other retinal disease, please write to info@retinaindia.org to be included in the database. Retina India also runs Connect Programs, which allow patients and family members interested in one particular diseases (e.g. Stargardt Connect) to connect with each other, which allows them to discuss and resolve their problems.
Retina India is a not-for-profit organization, registered with the Charity Commissioner, Mumbai, India, established for empowering people with retinal disorders, and bringing them and their families on a common platform with physicians, researchers, counselors, low vision and mobility experts and other specialists.
Monday, November 22, 2010
Treating colour blindness with Gene Therapy
Recent research has demonstrated that colour blindness may be capable of rescue by a simple sub-retinal injection of the genetic sequence for the missing photopigment. A research team, based at the University of Washington, have comprehensively shown that animals, previously documented to be colour-blind, are capable of colour discrimination within 20 weeks of treatment. The research not only adds optimism to the field of gene therapy for many other retinal disorders but also suggests an encouraging level of plasticity in how the brain manages new information.
Colour vision
Colour vision is both a fascinating and complex process. Fascinating because interpretation of the world around us through the capacity of colour vision almost defines the "human" experience; complex because the "sensation" of colour and fine acuity vision involves an array of highly differentiated and specialised cell types communicating with the cerebral cortex to create an output that continues to elude our detailed understanding.
To understand how an eye sees colour, click here.
The wavelengths of light visible to the human eye range between approximately 400nM and 700nM allowing humans to distinguish over a million different colours. This impressive feat is achieved through the processing of signals from three types of cone photoreceptor distinguished by their sensitivity to varying wavelengths: "S" (short) with a maximal sensitivity at about 430nM; "M" (medium) with a maximal sensitivity at about 530nM and finally; "L" (long) with a maximal sensitivity at about 560nM. The sensitivities however, accommodate broad "tuning" capabilities such that each type can respond to wavelengths across the visible light spectrum. The sensitivity of any particular photoreceptors are determined by the type of opsin expressed which, in turn, is determined by the sequence of amino acids that make up an opsin protein. Changes in the sequence of amino acids can change the spectral sensitivity for example, changes in 2 out of the approximate 350 amino acids in the L- and M- opsins in humans account for most of the 30nm difference in their peak wavelength sensitivities. Red-green colour blindness is a condition brought about through a disruption of either the long L- or the middle M- wavelength sensitive visual photopigments found in cone photoreceptors. Although the condition has been recognised and studied for over 200 years, the present research is the first report on the use of genetic technology to correct a deficit of colour vision in a mammalian species.
Colour blindness
Red-green colour blindness is among the most common genetic disorders found in humans. The incidence is known to vary with ethnicity (about 8% in Caucasian men, 4% in Japanese men and 3% in African men, and about 6-8% in Indians).
To understand how colour blindness affects sight, click here.
As the L- and M- wavelength sensitive visual photopigment genes ("OPN1LW"-opsin 1 long wave sensitive and "OPN1MW"-opsin 1 medium wave sensitive) are found concatenated head-to-tail along the X chromosome, this in part explains why the condition affects 3-8% of males but only 1% of females. Heterozygous carrier females are estimated at about 15% of the Caucasian population. In their research into correcting the colour deficit the University of Washington research team chose the New World squirrel monkey (Saimiri sciureus) as an experimental model. All male and some female squirrel monkeys are colour-blind "dichromats" (the three different types of cone photoreceptor make humans "trichromatic" whereas most other mammals in the animal kingdom have only two types of cone and are referred to as "dichromatic"). Dichromatic squirrel monkeys have S- cones and M- cones and the idea to deliver the L- photopigment gene sequence would allow the researchers, if successful, to demonstrate a change from dichromatic to trichromatic vision.
Insightful research
The research, led by Professors Jay and Maureen Neitz, was aimed not so much at developing a gene based therapeutic for the treatment of human colour blindness but more to demonstrate the principle of gene therapy for correcting a genetic fault in the retina. While the technology could be developed further and used to treat the condition in humans, it is likely that regulatory authorities would prefer to observe the use of gene therapy for more severe ocular disorders before approving such technology for use in an otherwise healthy retina.
The research group genetically engineered a copy of the human L-opsin gene (OPN1LW) under the control of the L/M opsin enhancer and promoter and packaged the transcript into the recombinant adeno-associated viral (AAV) genome (serotype 2, capsid 5). High-titre infectious particles were prepared and injected in batches of 100uL. Genetic regulatory elements were chosen to direct expression in M- rather than S- cones. Researchers treated colour-blind adult squirrel monkeys, colour blind from birth, with three sequential sub-retinal injections in different areas of the retina, each injection comprising a volume of approximately 100uL and in total containing an estimated 2.7 X 1013 virus particles. Prior to treatment, animals were trained to perform a computer based colour vision test (the Cambridge Colour Test) and control baseline results were built up from over a year's worth of testing.
Twenty weeks after administration, the results clearly demonstrated a change in the spectral sensitivity of a subset of the cone cell population as detected using a custom built wide-field colour multifocal electroretinogram system (mf-ERG). Following treatment, animals tested on the Cambridge Colour Test showed an improved threshold for blue-green and red-violet wavelengths and this improvement coincided with robust levels of transgenic gene expression previously reported for similarly treated squirrel monkeys. In short, the animals had gained trichromatic vision as soon as the new gene was producing opsin protein. So far the researchers have reported that the improvement in colour vision in treated animals has remained stable for more than 2 years. Plans are scheduled to continue testing to allow for long-term evaluation of the technology.
Teaching old monkeys new tricks
The signals for colour are processed through post-receptoral cells in the retina and brain and part of the processing includes computations in specific ganglion cells that subtract the signals received from different types of cone photoreceptor. Such computation, it was thought, develops specifically from birth contingent on the number and types of photoreceptors present. Adding a "new" signal to an established system was thought unlikely to work as the established system would not have developed the pathway required for that particular signal type. The current research from the University of Washington has changed that idea. As soon as the new photopigment is expressed in the retina, there is a simultaneous ability to process new wavelengths of light. Previously dichromatic monkeys acquired the capability for performing tasks of colour discrimination as proficiently as trichromats. This suggests a level of plasticity previously thought to be unlikely. Neural connections, it was thought, established during development would be unlikely to efficiently process "new inputs" (such as that delivered by the gene therapy). As both Prof. Jay and Maureen Neitz comment, "classic visual deprivation experiments [dating back to the 1960s] have led to the expectation that neural connections established during development would not appropriately process an input that was not present from birth. Therefore, it was believed that the treatment of congenital vision disorders would be ineffective unless administered to the very young". Cleary the results from the recent research suggest otherwise and the observations, reported in the journal Nature (Vol. 461, pp784-788), provide encouragement that gene delivery to the eye in the context of adult onset diseases may have a real prospect of success.
Next steps
The team are now looking at another retinal disorder - achromatopsia - and are planning to restore the missing or defective photoreceptor components to the healthy retina and thereby treat the disease in humans. Achomatopsia, meaning "without colour", is a disorder in which the individual is unable to distinguish colour due to a deficient cone mediated eletroretinogram and typically sufferers will have a severely compromised visual acuity. Approximately 1 in 30,000 individuals are affected by the disorder that can cause permanent central vision loss and for which no effective medical therapies exist. The University of Washington team is now testing a gene therapy approach in a mouse model of achromatopsia in an effort to reproduce the success demonstrated in the correction of colour-blindness.
- From Euretina
Colour vision
Colour vision is both a fascinating and complex process. Fascinating because interpretation of the world around us through the capacity of colour vision almost defines the "human" experience; complex because the "sensation" of colour and fine acuity vision involves an array of highly differentiated and specialised cell types communicating with the cerebral cortex to create an output that continues to elude our detailed understanding.
To understand how an eye sees colour, click here.
The wavelengths of light visible to the human eye range between approximately 400nM and 700nM allowing humans to distinguish over a million different colours. This impressive feat is achieved through the processing of signals from three types of cone photoreceptor distinguished by their sensitivity to varying wavelengths: "S" (short) with a maximal sensitivity at about 430nM; "M" (medium) with a maximal sensitivity at about 530nM and finally; "L" (long) with a maximal sensitivity at about 560nM. The sensitivities however, accommodate broad "tuning" capabilities such that each type can respond to wavelengths across the visible light spectrum. The sensitivity of any particular photoreceptors are determined by the type of opsin expressed which, in turn, is determined by the sequence of amino acids that make up an opsin protein. Changes in the sequence of amino acids can change the spectral sensitivity for example, changes in 2 out of the approximate 350 amino acids in the L- and M- opsins in humans account for most of the 30nm difference in their peak wavelength sensitivities. Red-green colour blindness is a condition brought about through a disruption of either the long L- or the middle M- wavelength sensitive visual photopigments found in cone photoreceptors. Although the condition has been recognised and studied for over 200 years, the present research is the first report on the use of genetic technology to correct a deficit of colour vision in a mammalian species.
Colour blindness
Red-green colour blindness is among the most common genetic disorders found in humans. The incidence is known to vary with ethnicity (about 8% in Caucasian men, 4% in Japanese men and 3% in African men, and about 6-8% in Indians).
To understand how colour blindness affects sight, click here.
As the L- and M- wavelength sensitive visual photopigment genes ("OPN1LW"-opsin 1 long wave sensitive and "OPN1MW"-opsin 1 medium wave sensitive) are found concatenated head-to-tail along the X chromosome, this in part explains why the condition affects 3-8% of males but only 1% of females. Heterozygous carrier females are estimated at about 15% of the Caucasian population. In their research into correcting the colour deficit the University of Washington research team chose the New World squirrel monkey (Saimiri sciureus) as an experimental model. All male and some female squirrel monkeys are colour-blind "dichromats" (the three different types of cone photoreceptor make humans "trichromatic" whereas most other mammals in the animal kingdom have only two types of cone and are referred to as "dichromatic"). Dichromatic squirrel monkeys have S- cones and M- cones and the idea to deliver the L- photopigment gene sequence would allow the researchers, if successful, to demonstrate a change from dichromatic to trichromatic vision.
Insightful research
The research, led by Professors Jay and Maureen Neitz, was aimed not so much at developing a gene based therapeutic for the treatment of human colour blindness but more to demonstrate the principle of gene therapy for correcting a genetic fault in the retina. While the technology could be developed further and used to treat the condition in humans, it is likely that regulatory authorities would prefer to observe the use of gene therapy for more severe ocular disorders before approving such technology for use in an otherwise healthy retina.
The research group genetically engineered a copy of the human L-opsin gene (OPN1LW) under the control of the L/M opsin enhancer and promoter and packaged the transcript into the recombinant adeno-associated viral (AAV) genome (serotype 2, capsid 5). High-titre infectious particles were prepared and injected in batches of 100uL. Genetic regulatory elements were chosen to direct expression in M- rather than S- cones. Researchers treated colour-blind adult squirrel monkeys, colour blind from birth, with three sequential sub-retinal injections in different areas of the retina, each injection comprising a volume of approximately 100uL and in total containing an estimated 2.7 X 1013 virus particles. Prior to treatment, animals were trained to perform a computer based colour vision test (the Cambridge Colour Test) and control baseline results were built up from over a year's worth of testing.
Twenty weeks after administration, the results clearly demonstrated a change in the spectral sensitivity of a subset of the cone cell population as detected using a custom built wide-field colour multifocal electroretinogram system (mf-ERG). Following treatment, animals tested on the Cambridge Colour Test showed an improved threshold for blue-green and red-violet wavelengths and this improvement coincided with robust levels of transgenic gene expression previously reported for similarly treated squirrel monkeys. In short, the animals had gained trichromatic vision as soon as the new gene was producing opsin protein. So far the researchers have reported that the improvement in colour vision in treated animals has remained stable for more than 2 years. Plans are scheduled to continue testing to allow for long-term evaluation of the technology.
Teaching old monkeys new tricks
The signals for colour are processed through post-receptoral cells in the retina and brain and part of the processing includes computations in specific ganglion cells that subtract the signals received from different types of cone photoreceptor. Such computation, it was thought, develops specifically from birth contingent on the number and types of photoreceptors present. Adding a "new" signal to an established system was thought unlikely to work as the established system would not have developed the pathway required for that particular signal type. The current research from the University of Washington has changed that idea. As soon as the new photopigment is expressed in the retina, there is a simultaneous ability to process new wavelengths of light. Previously dichromatic monkeys acquired the capability for performing tasks of colour discrimination as proficiently as trichromats. This suggests a level of plasticity previously thought to be unlikely. Neural connections, it was thought, established during development would be unlikely to efficiently process "new inputs" (such as that delivered by the gene therapy). As both Prof. Jay and Maureen Neitz comment, "classic visual deprivation experiments [dating back to the 1960s] have led to the expectation that neural connections established during development would not appropriately process an input that was not present from birth. Therefore, it was believed that the treatment of congenital vision disorders would be ineffective unless administered to the very young". Cleary the results from the recent research suggest otherwise and the observations, reported in the journal Nature (Vol. 461, pp784-788), provide encouragement that gene delivery to the eye in the context of adult onset diseases may have a real prospect of success.
Next steps
The team are now looking at another retinal disorder - achromatopsia - and are planning to restore the missing or defective photoreceptor components to the healthy retina and thereby treat the disease in humans. Achomatopsia, meaning "without colour", is a disorder in which the individual is unable to distinguish colour due to a deficient cone mediated eletroretinogram and typically sufferers will have a severely compromised visual acuity. Approximately 1 in 30,000 individuals are affected by the disorder that can cause permanent central vision loss and for which no effective medical therapies exist. The University of Washington team is now testing a gene therapy approach in a mouse model of achromatopsia in an effort to reproduce the success demonstrated in the correction of colour-blindness.
- From Euretina
Saturday, November 20, 2010
Stem cell treatment shows promise for Leber's Congenital Amaurosis (LCA) in animal trials
Approximately 200,000 children across the globe (and 12,500 in India) seem to be suffering from a kind of inherited childhood blindness known as Leber Congenital Amaurosis (LCA). It is assumed that light sensitive photoreceptor cells in the retina are forced to die in this disease which further leads to loss of vision. University College London Investigators have introduced a stem cell treatment that may replace diseased parts of the retina. This discovery can possibly promise future treatment for retinal diseases affecting several kids.
Scientists claim to have successfully implanted cells from healthy mice into mice with LCA. The implanted gene is believed to express a gene called Crx, vital for making healthy cone and rod photoreceptors. Having successfully merged with the retina, cells seemingly became new cone photoreceptors. Cone photoreceptors are key components for reading vision and colour vision.
This is the first time that researchers have demonstrated the possibility of transplanting new cone photoreceptors into mature retina. Recent research has shown that embryonic stem cells capable of self-renewal could provide an equivalent source of human cells that express the Crx 'photoreceptor-creating' gene and could be grown in the lab before being transplanted in the retina.
The research highlights that it may be possible to treat a disease such as LCA by photoreceptor cell transplantation via use of stem cells. It may also be possible for treatment intervention at various stages of the disease, which increases the chances of treatment for more number of patients.
LCA has been a disease of focus as one of the only two diseases in medicine that has shown significant improvement with gene therapy treatment. This study demonstrates success for treatment of LCA in animal trials. But more studies will need to be performed, since stem cell derived cells need to demonstrate that they have lost the capability of further division and differentiation. Further investigations are needed to demonstrate possibilities of restoring sight with this newly developed treatment.
Scientists claim to have successfully implanted cells from healthy mice into mice with LCA. The implanted gene is believed to express a gene called Crx, vital for making healthy cone and rod photoreceptors. Having successfully merged with the retina, cells seemingly became new cone photoreceptors. Cone photoreceptors are key components for reading vision and colour vision.
This is the first time that researchers have demonstrated the possibility of transplanting new cone photoreceptors into mature retina. Recent research has shown that embryonic stem cells capable of self-renewal could provide an equivalent source of human cells that express the Crx 'photoreceptor-creating' gene and could be grown in the lab before being transplanted in the retina.
The research highlights that it may be possible to treat a disease such as LCA by photoreceptor cell transplantation via use of stem cells. It may also be possible for treatment intervention at various stages of the disease, which increases the chances of treatment for more number of patients.
LCA has been a disease of focus as one of the only two diseases in medicine that has shown significant improvement with gene therapy treatment. This study demonstrates success for treatment of LCA in animal trials. But more studies will need to be performed, since stem cell derived cells need to demonstrate that they have lost the capability of further division and differentiation. Further investigations are needed to demonstrate possibilities of restoring sight with this newly developed treatment.
Treatment for severe form of Retinopathy of Prematurity (ROP)
A study from Iran has shown that an injection of bevacizumab (or Avastin) injection into the eye of a baby with severe form of Retinopathy of Prematurity (ROP) may be effective for treating such cases that are associated with significant bleeding in the eye.
The study enrolled 14 eyes of eight premature infants, all of whom had one or two sessions of laser treatment and were given injection of Avastin (bevacizumab by Genentech Company) immediately after diagnosis of bleeding or hemorrhage in the eye. Follow-up examinations were conducted at 1, 3, 7 and 14 days and 1, 2 and 3 months after injection. Plus disease (which is one of the severe stages of ROP) started to subside 1 day to 3 days after injection, and disappeared completely in all eyes within 2 weeks. At final follow-up, all eyes were stable with attached retinas and normal appearing blood vessels in the retina.
Avastin, a drug that has shown significant treatment potential in various retinal conditions, including age-related macular degeneration, diabetic retinopathy, retinopathy of prematurity, vasicular occlusions, and even some conditions in patients with retinitis pigmentosa, has been shown to be effective in the severe forms of retinopathy of prematurity patients. Previously, such patients were treated with extensive laser sessions, which was difficult to treat in eyes with bleeding, since laser treatment cannot be performed in eyes with blood. Such babies had to be followed up significantly every few days to check for any evidence of progression of the disease. Considering that these are premature babies, usually in a neonatal intensive care unit, and some of them with other medical problems, such follow-up exams are usually very stressful for everyone involved; the infant baby, the neonatologist and the retina specialist who is examining and treating the baby. Hence, having an additional treatment significantly helps a retinal specialist.
Ref: Graefes Arch Clin Exp Ophthalmol. 2010 Dec;248(12):1713-8. Epub 2010 Jun 27.
The study enrolled 14 eyes of eight premature infants, all of whom had one or two sessions of laser treatment and were given injection of Avastin (bevacizumab by Genentech Company) immediately after diagnosis of bleeding or hemorrhage in the eye. Follow-up examinations were conducted at 1, 3, 7 and 14 days and 1, 2 and 3 months after injection. Plus disease (which is one of the severe stages of ROP) started to subside 1 day to 3 days after injection, and disappeared completely in all eyes within 2 weeks. At final follow-up, all eyes were stable with attached retinas and normal appearing blood vessels in the retina.
Avastin, a drug that has shown significant treatment potential in various retinal conditions, including age-related macular degeneration, diabetic retinopathy, retinopathy of prematurity, vasicular occlusions, and even some conditions in patients with retinitis pigmentosa, has been shown to be effective in the severe forms of retinopathy of prematurity patients. Previously, such patients were treated with extensive laser sessions, which was difficult to treat in eyes with bleeding, since laser treatment cannot be performed in eyes with blood. Such babies had to be followed up significantly every few days to check for any evidence of progression of the disease. Considering that these are premature babies, usually in a neonatal intensive care unit, and some of them with other medical problems, such follow-up exams are usually very stressful for everyone involved; the infant baby, the neonatologist and the retina specialist who is examining and treating the baby. Hence, having an additional treatment significantly helps a retinal specialist.
Ref: Graefes Arch Clin Exp Ophthalmol. 2010 Dec;248(12):1713-8. Epub 2010 Jun 27.
Ocuseva, a drug in clinical trial in Japan for treatment of Retinitis Pigmentosa
R-Tech Ueno Ltd. (Tokyo, Japan) announced it has completed a phase 2 clinical trial of 0.15% UF-021 isopropyl unoprostone (Ocuseva), which is under development as a treatment for retinitis pigmentosa (RP). The trial investigated the possibility of improving visual function in the central part of the retina with UF-021 in patients with RP.
The randomized, multicenter, comparative study examined 112 patients with RP that had progressed to the mid-to late-stage, defined as a visual acuity of less than 6/18 with a narrow visual field. Patients received placebo or Ocuseva, instilled one drop per time or two drops per time (at a 5 minute interval), twice a day in the morning and evening for 24 weeks. The primary efficacy endpoint was the change seen on the visual field analysis as checked by an instrument called the MP-1 microperimeter (Nidek, Gamagori, Japan), Retinal sensitivity was also studies by a regular Humphrey visual field analyzer (10-2), visual acuity, contrast sensitivity, and health-related quality of life, using a questionnaire on visual function (VFQ-25).
After 24 weeks, positive change in the retinal sensitivity of the central 2 degree field of vision from baseline increased the most in the two-drops-per-time group, followed by the one drop- per-time group. The placebo group had the least significant increase in sensitivity.
The change in the retinal sensitivity from the pretreatment level by 4 dB or more was seen as improvement in 15.2% of patients in the placebo group, 7.9% in the one-drop-per-time group, and 18.4% in the two-drops-per-time group, whereas the change was seen as aggravation in 21.2% in the placebo group, 15.8% in the one-drop-per-time group, and 2.6% in the two-drops-per-time group. There were a significantly lower number of aggravated cases in the 2-drops-per-time group, compared with the placebo group. The retinal sensitivity measured with the Humphrey perimeter showed statistically significant improvement at weeks 4 and 8 in the two-drops-per-time group compared with the placebo group.
The main adverse effect of Ocuseva was ocular irritation, which, the company said, disappears several minutes after instillation.
The results show promise, specifically with the advantage that it only requires instillation of drops, rather than a completed surgical intervention. Ocular irritation, which anyway lasts a few minutes, is the only adverse effect. The follow-up in the trial is 6 months (24 weeks), which is considered good enough to consider in any retinal trial. The only thing difficult to understand is the group that was instilled with placebo drops (meaning no medication) still showed improvement in about 17 of the 112 patients in the trial (15.2%).
After 24 weeks, positive change in the retinal sensitivity of the central 2 degree field of vision from baseline increased the most in the two-drops-per-time group, followed by the one drop- per-time group. The placebo group had the least significant increase in sensitivity.
The change in the retinal sensitivity from the pretreatment level by 4 dB or more was seen as improvement in 15.2% of patients in the placebo group, 7.9% in the one-drop-per-time group, and 18.4% in the two-drops-per-time group, whereas the change was seen as aggravation in 21.2% in the placebo group, 15.8% in the one-drop-per-time group, and 2.6% in the two-drops-per-time group. There were a significantly lower number of aggravated cases in the 2-drops-per-time group, compared with the placebo group. The retinal sensitivity measured with the Humphrey perimeter showed statistically significant improvement at weeks 4 and 8 in the two-drops-per-time group compared with the placebo group.
The main adverse effect of Ocuseva was ocular irritation, which, the company said, disappears several minutes after instillation.
The results show promise, specifically with the advantage that it only requires instillation of drops, rather than a completed surgical intervention. Ocular irritation, which anyway lasts a few minutes, is the only adverse effect. The follow-up in the trial is 6 months (24 weeks), which is considered good enough to consider in any retinal trial. The only thing difficult to understand is the group that was instilled with placebo drops (meaning no medication) still showed improvement in about 17 of the 112 patients in the trial (15.2%).
Welcome to Retina India
Retina India is a not-for-profit organization, registered with the Charity Commissioner, Mumbai, India, established for empowering people with retinal disorders, and bringing them and their families on a common platform with physicians, researchers, counselors, low vision and mobility experts and other specialists.
Why do we need another not-for-profit organization?
India is home to approximately 24 million blind people, the largest in the world. Additionally, there are another 52 million visually impaired in the country. It is thought that if this trend is allowed to continue, the number of blind people would increase to 31.6 million by 2020.
The blindness-prevention programs that are sponsored by governmental agencies and by non governmental organizations (NGOs) usually focus on "avoidable" or "preventable" blindness that commonly includes cataract and corneal problems. Even though patients with preventable blindness in India are significant, the prevalence of retinal ailments, such as retinitis pigmentosa and allied disorders, macular degeneration, diabetic retinopathy, etc. is gradually increasing. Some of these diseases do not even have a cure at this time, and usually leave the affected people with permanent visual impairment for a lifetime. There has been no singular effort in India to unite the efforts in the fields of medical research, education, rehabilitation and welfare of people with retinal disorders.
It is this void that Retina India aims to fill.
Retina India is focused on spreading awareness amongst society, the NGOs and the Governmental agencies about people with retinal ailments and the specific issues they and their families face. We also wish to help them make a difference to their own lives, and to the lives of people around them.
Our Vision
To empower patients and families of patients with retinal ailments, and help them make a significant contribution to their own lives, and to the lives of people around them.
Our Mission
To increase awareness of retinal diseases and champion the cause of people who get affected by them, and to induce increased research efforts towards treatment for such diseases.
Our people
Simply said, Retina India is a movement, It is a movement that includes all of you. It is our strong belief that when people come together, and work towards a common cause, a lot can get done.
Retina India includes patients with retinal disorders and their families. It also includes retinal specialists and other ophthalmologists with an interest in retinal diseases, low vision experts, mobility experts, counselors, and others. We invite people with a social spirit, who have an inherent desire to do something good for others, and make a difference in someone's life, to volunteer and be a part of this movement. We also invite young adults, school and college students, to gain experience in working on a project for Retina India .
Our Key Objectives:
Patient Alliance: The alliance brings together patients with retinal disorders, along with their families and friends, to work for mutual benefit.
Medical Research and Treatments: Retina India highlights, coordinates and sponsors research in retinal treatment in India, while also informing the patients and their families about the current on-going research in India and around the world.
Clinical trials in India: We act as a channel to bring new treatments and technologies to India (Gene Therapy, Artificial Retina, Stem-Cell treatment, etc.) for Indian patients with retinal disorders.
Patient Registry: Retina India maintains databases (or registries) of patients with specific retinal diseases. Such registries will help inform patients likely to benefit from new treatments, such that they are not left to wonder whether a new treatment is beneficial to them or not, and in the process, spend a lot of time, effort and money in finding that out. Registries for Retinitis Pigmentosa, Macular Degeneration, Retinopathy of Prematurity, Leber's Congenital Amaurosis, etc. are already functional.
Education, Counseling & Advocacy: Activities range from encouraging beneficiaries to pursue their lives productively, counseling them about education, employment, marriage and family issues, to rehabilitation, independence training and mobility skills via associations with other organizations in the country. We are also commited to advocacy about the concerns of people with retinal ailments.
We welcome you to make a difference in your own life, and in the lives of people around you.
Why do we need another not-for-profit organization?
India is home to approximately 24 million blind people, the largest in the world. Additionally, there are another 52 million visually impaired in the country. It is thought that if this trend is allowed to continue, the number of blind people would increase to 31.6 million by 2020.
The blindness-prevention programs that are sponsored by governmental agencies and by non governmental organizations (NGOs) usually focus on "avoidable" or "preventable" blindness that commonly includes cataract and corneal problems. Even though patients with preventable blindness in India are significant, the prevalence of retinal ailments, such as retinitis pigmentosa and allied disorders, macular degeneration, diabetic retinopathy, etc. is gradually increasing. Some of these diseases do not even have a cure at this time, and usually leave the affected people with permanent visual impairment for a lifetime. There has been no singular effort in India to unite the efforts in the fields of medical research, education, rehabilitation and welfare of people with retinal disorders.
It is this void that Retina India aims to fill.
Retina India is focused on spreading awareness amongst society, the NGOs and the Governmental agencies about people with retinal ailments and the specific issues they and their families face. We also wish to help them make a difference to their own lives, and to the lives of people around them.
Our Vision
To empower patients and families of patients with retinal ailments, and help them make a significant contribution to their own lives, and to the lives of people around them.
Our Mission
To increase awareness of retinal diseases and champion the cause of people who get affected by them, and to induce increased research efforts towards treatment for such diseases.
Our people
Simply said, Retina India is a movement, It is a movement that includes all of you. It is our strong belief that when people come together, and work towards a common cause, a lot can get done.
Retina India includes patients with retinal disorders and their families. It also includes retinal specialists and other ophthalmologists with an interest in retinal diseases, low vision experts, mobility experts, counselors, and others. We invite people with a social spirit, who have an inherent desire to do something good for others, and make a difference in someone's life, to volunteer and be a part of this movement. We also invite young adults, school and college students, to gain experience in working on a project for Retina India .
Our Key Objectives:
Patient Alliance: The alliance brings together patients with retinal disorders, along with their families and friends, to work for mutual benefit.
Medical Research and Treatments: Retina India highlights, coordinates and sponsors research in retinal treatment in India, while also informing the patients and their families about the current on-going research in India and around the world.
Clinical trials in India: We act as a channel to bring new treatments and technologies to India (Gene Therapy, Artificial Retina, Stem-Cell treatment, etc.) for Indian patients with retinal disorders.
Patient Registry: Retina India maintains databases (or registries) of patients with specific retinal diseases. Such registries will help inform patients likely to benefit from new treatments, such that they are not left to wonder whether a new treatment is beneficial to them or not, and in the process, spend a lot of time, effort and money in finding that out. Registries for Retinitis Pigmentosa, Macular Degeneration, Retinopathy of Prematurity, Leber's Congenital Amaurosis, etc. are already functional.
Education, Counseling & Advocacy: Activities range from encouraging beneficiaries to pursue their lives productively, counseling them about education, employment, marriage and family issues, to rehabilitation, independence training and mobility skills via associations with other organizations in the country. We are also commited to advocacy about the concerns of people with retinal ailments.
We welcome you to make a difference in your own life, and in the lives of people around you.
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