Musings over a cup of sambar

It's not just the sight, but smells and sounds have the ability to transport someone to a different place, a different time. It happens too often for someone who suffered progressive vision loss. Here's the experience of one of them.

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In spite of the clattering of plates and the high-decibel noise, the restaurant seemed more appealing. It doesn't require a genius to figure out why? The smell of coffee lured us from quite a distance, and as we wade through the crowd milling around the tables, we were assailed bythe smell of sambar.

The aroma transported me to a different place, to a different time.

Friday evening at our home town of Viruddachalam (better known these days as the former constituency of actor-politician Vijayakant). The bazaar road would be chaotic with fast moving 'town buses' and trucks carrying loads of sugarcanes and groundnuts. Roadside tea stalls did brisk business, and the police station that sat at the corner of the Double street looked more magical as the lone tube light inside flickered and flashed at regular intervals.

Having spent a full day playing cricket on the dry riverbank, myself and my brother would feel hardly tired as we looked forward to the prospect of eating the evening snack outside. We invariably went to the thatched roof stall of Adai Rayar, whose serves special 'onion adai' with tasty 'Milagai podi' (chilli powder) and gingili oil.

That was, of course, the popular choice. The thick dosa like dish would arrive the moment Rayar Mama saw uncle cycling with a nephew each on the front and back of the saddle. While everyone preferred to eat the crisp and wonderfully fried Adai with chilli powder, my choice was the other

one: vegetable sambar and coconut chatni. Rayar was too happy to serve the sambar several times, especially to me since I never used to waste even a drop. How can I? It was one of the best thing I had ever tasted.

It was harder to say what made the sambar tasty. It could be the dal or the native tamarind and vegetable. My guess was the proportion and the blend, which needed immense skill to reproduce without any change on a daily basis.

With the red mark on his forehead and customary dhoti-towel, not to mention the trademark smile, Rayar offered the best food in the town. The Adai, made with red gram-rice-red chilli paste, topped the billing.

The sambar we tasted at the restaurant didn't live up to the sweetness of its smell. But thoughts of Adai Rayar and the tasty sambar at his modest stall seemed to have done the trick. There was only the smile and no complaints of the tanginess due to excess tamarind juice. Oh yes, the mind often crawls through scenes of the past, morphing the unpleasantness of the present with fond memories.

- Learner

Tripping and falling isn’t a blindness problem

It was a warm March Sunday evening as I stepped out of my front door to alight a flight of steps for dinner at my sister’s place. Everything appeared usual: I was humming a favourite song, my daughter ran in the front toward the gate downstairs and I was cautious as I possibly can as I descended down the first step.

I don’t know about other blind persons, but for me walking on long stairways is fun. Be it walking up or getting down, I enjoy it because stairways are one place where we don’t need anyone’s help. The moment I hit the stairway, I ask, “Where’s the railing?” and follow it without expecting assistance. Believe me, walking alone with absolutely nothing to interrupt you, is a particularly liberating feeling for a blind man. So, I usually take brisk steps and even run if I am confident that the stairway is obstacle free.

The two-floor ascent at office is something I enjoy since they are familiar, and I use my break to walk down to have water. For someone confined to the chair throughout the working hours, this is a welcome relief. But imagine my shock when I was very close one day to kicking a bucket heavy with water!! (It was apparently kept by house keeping person for mopping the stairway.)

I thanked my stars for not falling over the bucket, and plunging seven or eight steps down, which would have surely broken my ankle or knee. People around me started cautioning me almost immediately about how I should be careful – putting out my hand and walking one step at a time and so on. “Do you walk like that?” I asked obviously exasperated by the way people treat me because of my blindness.

The funny thing is that stairways are supposed to be obstacle-free and no one expects a bucketful of water on the middle of the climb. And no one either questioned or instructed the house keeping person not to do it again. “It’s too early to kick the bucket” I joked with a colleague and explained the housekeeper about the dangers of keeping things like buckets on the way.

Back on that Sunday at home, I was getting down the steps and tripped suddenly. I lost control and went on a free fall and dashed my head against a wall in the front of the landing. This was far costlier than the near miss of ‘kicking the bucket’ as I felt lingering pain in my right temple and broke a half-grown wisdom tooth which made me sit through an agonizing dental surgery.

No one can predict accidents and probably that’s why it is accident. I also understand the concerns of people and feel touched when they take a moment to enquire about my condition and offer their genuine support in so many little ways. In fact, that is the best thing about being blind: you are always loved, supported and protected by people you barely know. The condition of blindness in a person evokes kindness in others and so they respond to our situation as if it were something that hurts them.

But when people somehow presume that I am sloppy or must act differently in this situation because of my blindness, I tend not to agree with that. As people without a vital sense, our body has various defense mechanisms to protect us (this is something purely instinctual and reflex) so usually you don’t find a blind person falling over something despite worries of people around him/her. By law of average, even that is bound to fail once in a way, not because the mechanism is faulty, but because our environment is full of unpredictabilities.

Should my blindness be blamed for this? I don’t know. Probably those who read and analyze this may have better answers.

- L Subramani, Bangalore

The journey continues...

Retina India congratulates Mr Avneesh Singh from New Delhi for his completion of the Executive MBA program from the Indian Institute of Management (IIM), Kozhikode. (Ed: For those not in the know, Kozhikode is situated in the State of Kerala, on the south-west coastal border of India.)

Since Mr Avneesh Singh's MBA journey, as much as others like Mr Pranav Lal from New Delhi, and Mr Vishal Jain, who is currently studying at IIM Lucknow, are inspiring to others, we thought we should share this story with you. Below is Mr Singh's story, in his own words. Enjoy, and get inspired!

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"Dear all, I will like to share  the journey of the last 13 years, which has many transitional stages, but it has led to a satisfactory life so far.

I always had a passion for mechanical engineering. I could never imagine a life without machines, especially when machines create speed. This keen interest in speed & engineering made me specialize in thermal sciences in my mechanical engineering course.

When I came to know about the progress of my retinal degeneration, this keenness suffered a big blow. It was shocking to know that I will have to give up my ardent desire for speed & machines. Leave aside driving, I will not even be able to walk well with reduced vision.

Many suggested to me to leave the field of engineering, and switch to a safer profession like management or bank officer, but it was an excruciating idea for me. I realized that mechanical engineering was not practical now, but it was very difficult to abandon my passion. Moreover, the alternatives, such as becoming a bank officer, were something that my mind could just not accept.

To go on with my zest for engineering, I finally decided to pursue my career in computers that looked more viable, due to availability of assistive technologies like magnifiers, high contrast mode etc.

It was initially hard to create interest in computer engineering, which I always considered to be inferior to mechanical, because it lacked high speed adventure that is integral part of thermal sciences. But since it was the only practicable path at that time, I pushed through it.

Vision loss was even rapid in last few semesters of my degree. I was able to complete computer engineering but future looked quite uncertain.

I used to ask the ophthalmologists I consulted about the rate of degeneration, and the amount of time I had before I loose my useful vision, but all of them gave me hope instead of stating facts. I knew that macula in my left eye was degenerating very rapidly, and right eye would be following the degeneration in the same pattern. So one day, I bluntly asked an ophthalmologist that I know that I am loosing reading capability, and whether it was time for me to start learning Braille and similar skills. He replied with hesitation that I should start some practice of Braille.

This thought of learning Braille was not tolerable for my parents because I could still somehow read, but I was stubborn on this issue and made my way to the AICB- New Delhi, where I started learning all the skills that were now a must for self subsistence.

Accepting blindness was very tough for both me and my parents, but this step became one of the turning stones in my life. It helped me overcome fear of the approaching blindness, preparing me for the worst-case scenario, and actually made me more efficient in performing day-to-day activities.

But at the same time, it also made me realize that rehabilitation centres are overlooking the new generation enabler, the technological advancements that information technology is presenting, and are actually underestimating the potential of visually impaired.

I continued working as freelance programmer and kept on refining my potency in JAWS scripting and using programming platforms with the help of JAWS.

Some months later, I visited NAB Delhi and met Mr. Dipendra Manocha. After getting to know of my engineering & programming skills, he suggested me to start contributing to accessibility related projects. He encouraged me by stating that I am a rare combination who knows the needs (as I myself suffer from vision loss), and also have the capability to develop access technology. I came to know about DAISY books then, while Mr. Manocha also introduced me to the field of accessible digital publishing. Finally, I ended up working with the DAISY Consortium as a software developer.

A couple of years later, I got the responsibility of leading the Obi project – the audio NCX book production tool. The success of Obi was a benchmark in my career that helped me gain the trust of my seniors that resulted in attaining the responsibility of the Obi-Tobi project, formerly known as the Urakawa project. Now, I was not only leading the cutting edge project, but was also involved in research of upcoming technology along with experienced minds from different parts of the world.

Along with the professional development, my academic life also took on a new dimension. After 5 years of experience in technology development, I thought of going for management education because now my ambition of becoming a self dependent engineer was fulfilled and I was leading software development projects.

It was time to look for proper management education and with God’s grace, I got admission in Indian Institute of Management – Kozhikode in year 2008. Now I was again a student, completely dependent on screen readers, and the problems of accessible books rose up again. But there was no effective solution available.

The administration of the institute told me that none of them had any experience of having a visually impaired student. It took some months to get the minimum facilities required for visually impaired. In first 2 terms, I could not even get extra time for giving exam through scribe. But gradually, the guidelines were formed, and most of the things were sorted out as the course progressed. This was a learning experience for the institute also, so such of the problems were, in a way, expected. IIM-K also tried to contact publishers for electronic copies of books for me, but publishers were not able to provide any of them.

I graduated from IIM-Kozhikode in early 2010. But it was not the end of my academics. My vision loss had moulded my fascination for machines into a quest for understanding war strategies, and the study of human mind. So I decided to go further for advanced specialization in strategy.

It was a challenging year, full of excitement, stress & many amazing experiences that tested me and also helped me develop me into a mature person.

On March 17, 2012, I graduated from Indian Institute of Management – Kozhikode in Executive MBA specialized in strategy. It was satisfactory to successfully complete one of the most rigorous management programs in India, but I will say that it is just a milestone.

A long journey still lies ahead. Now, along with project management responsibilities, I am also part of strategy formulation management team of DAISY Consortium.

And the journey continues...

With regards,
Avneesh Singh

New animal model may help develop new treatments for RP

Developing new treatments for diseases such as RP have been difficult for many reasons. Apart from the fact that it was difficult to pinpoint the genetic defect in the disease, lack of an adequate animal model that could be used to test any new treatment to study its effect and follow the effect for a few months has been an underlying problem for many years now.   

Hence the recent publication in IOVS of success in creating a genetically modified mini-pig may help in the development of newer and improved treatment paradigms, and may eventually help lead us to a cure diseases such as retinitis pigmentosa (RP), which is the most common inherited retinal disease in India. The researchers used miniature pigs, weighing about 150 pounds at full growth, instead of the larger pig, since managing the smaller pigs was much more easier. 

This model has been developed by researchers in the Department of Ophthalmology & Visual Sciences at the University of Louisville, along with researchers from the National Swine Resource and Research Center, University of Missouri.

For those from the scientific background, here's the abstract from IOVS. " ... describes the creation of an inbred, transgenic mini-pig that carries a mutant human rhodopsin gene which is expressed in the retina and is associated with progressive loss of light-evoked ERG responses. This is a significant achievement of considerable practical value in an era in which translational activity for retinal diseases is burgeoning. The rationale for generating this pig is laid out well, and the design appears to have multiple advantages over the existing retinal dystrophic pig. There are many rodent models of retinitis pigmentosa (RP) and conditions resembling RP, but what has been lacking is a large animal model that more accurately mimics the situations encountered when treating human patients. One potential animal model is the pig. There is an existing pig model of retinal degeneration (RD); however, a number of factors have made this model difficult to use, including the large size of the animals at the time of degeneration as well as molecular genetic considerations. The article describes the successful development of a genetically accurate RP-like condition in a mini-pig.

This model should prove quite valuable to people working on treatment of RD, including traditional pharmacologic approaches and regenerative strategies, such as stem cell transplantation. The authors evaluated six transgenic founders whose retinal function was studied with full-field electroretinography from three months through two years. Progeny from one founder were generated and genotyped to determine the transgene inheritance pattern. Retinal mRNA was isolated and the ratio of P23H to wild-type pig RHO measured. The result is a powerful new tool for retinal degeneration research that should be of interest to a wide range of workers in that field."

The Pro23His (P23H) rhodopsin (RHO) mutation is the cause for the most common form of human autosomal dominant retinitis pigmentosa (adRP), with a high propensity for disease characteristics to pass to the next generation. This study was focused on establishing a transgenic miniature swine model of RP using this human P23H RHO gene. 

Animal models are used to screen for safety and efficacy of new treatment paradigms for diseases such as RP, which includes newer treatment modalities such as medications, stem cell therapies, gene therapy, and the artificial retinal prosthesis.

The prevalence of RP in India is considered to be significantly higher compared to other nations. With some small sample studies indicating that RP may affect about 1 in 1000 in some areas, to almost 1 in 500 in some rural areas in India, we potentially have a population of about a million RP patients. 

Sources: 1 2

App turns tablet into math aid for visually impaired students

From www.physorg.com: Article link here.

For the video, please click here.

Without looking down, Kira runs her index finger across the screen of an Android tablet that she is holding in her lap. For the occasion, she has painted her fingernails bright pink. When her finger touches a line drawn on the screen, the tablet vibrates quietly. Scanning her finger back and forth and feeling the vibration come and go allows her to trace the line's path. When her finger reaches a pink dot, the tablet gives off an electronic tone and she grins delightedly.

Kira is one of two visually impaired high school students who are testing a new Android app, one designed to assist students like her in mastering algebra, geometry, graphing and other subjects that are particularly hard to comprehend without the aid of normal vision.

The app is the brainstorm of Jenna Gorlewicz, a graduate student in the Medical and Electromechanical Design Laboratory (MED Lab) at Vanderbilt University, and her advisor Robert Webster, an assistant professor of mechanical engineering, who directs the lab. Given the enthusiastic reaction of Kira, her classmate Quinn and their teacher, her innovation could have a major impact on how science, technology, engineering and math – the critical STEM subjects – are taught to the visually impaired.

A major change in direction

The project is a considerable change from the research projects that Gorlewicz pursued during her first two years in the MED Lab. Supported by a fellowship from the National Science Foundation, she worked on improving cochlear implant surgery and miniaturizing endoscopic robotic capsules. But she wasn't completely satisfied: "I'm a real people person," she explained. "So I wanted a project that would let me interact directly with the people it was helping."

"Jenna kept saying that she wanted to work more with people, so we began exploring other possible projects," said Webster. "Fortunately, her fellowship and my NSF CAREER Award gave us enough flexibility to think outside the box and explore a wide variety of thesis topics for her."
One of the ideas they came up with was a study of the effectiveness of haptic technology: technology that takes advantage of a user's sense of touch by applying forces, vibrations or motions to enhance remote control of machines, devices or virtual objects. The lab was experimenting with haptic interfaces to control some of their biomedical robots.

Matching haptics with visually impaired

"When I began reading articles about haptic technology being incorporated into these new touch screen devices, I realized that the people who really need haptics are people with impaired vision because they heavily rely on their sense of touch to 'see' the world around them." Gorlewicz said. "I love math and I love teaching, so I immediately thought of using them for math education, because it has such a strong visual component." After she did some research into the methods that are currently used to teach mathematics to the visually impaired, she became even more enthusiastic about her idea.

When she started the new project 18 months ago, the only off-the-shelf tablet that Gorlewicz could find that included tactile feedback was a $2,500 model produced for industrial and commercial applications. Since then haptic feedback has been added in a number of consumer tablets that sell for as little as $300.

The grad student has programmed these tablets so they vibrate or generate a specific tone when the student's fingertip touches a line, curve or shape displayed on the screen. The devices can generate vibrations with a number of different frequencies and hundreds of different sounds. This allows Gorlewicz to assign different tactile or audio signals to different features. For example, in an exercise that includes an X-Y grid, she can set the horizontal and vertical lines to vibrate at different frequencies and set points to make a certain tone. In this way, it's easier for the students to distinguish between the gridlines and the points on the grid.

"If one of these tablets were networked wirelessly to the teacher's computer, then, when he or she projects a graph or equation on the screen at the front of the class, the same graph would appear on the student's tablet. They could then use their senses of touch and hearing to follow the content the teacher is discussing," Gorlewicz said.

"When Jenna first approached me with the idea, I thought it would be interesting and might be some small help," said Ann Smith, the teacher of the visually impaired who works with Kira and Quinn at Hillsboro High School in Nashville. "The more experience I have with it, the more valuable I think it could be. It makes the work more accessible. The students are really interested and they talk about it even when Jenna isn't here."

Hillsboro High follows the approach of including students with special needs in classes with their sighted peers as much as possible. That means Kira and Quinn attend general education classes. Smith sits with them during their math classes and uses various methods to ensure that they can follow the teacher's presentation. With Quinn, who can read Braille and see large print, this involves duplicating the shapes and figures the teacher is using on a small white board that he can hold close enough to see. In Kira's case Smith must use tactile aids like pins and pipe-cleaners on a bulletin board with raised graphing lines to reproduce complex mathematical shapes that Kira can feel with her fingers.

"Because this takes a certain amount of time, we are always one or two steps behind the teacher," Smith said. "One of these haptic tablets would allow them to keep up much better. If I didn't have to attend class with them, it would also make them feel more independent."

Smith also pointed out that such a tablet can be used by students with widely differing degrees of impairment because it combines visual, tactile and audio capabilities.

Some learning required

According to Kira and Quinn, there is a little bit of a learning curve with the new device. "At first, I didn't think this would help me," Quinn said. "But after I started using it I found that it can be very helpful." According to Kira, "The biggest obstacle was getting the correct mental images. However, once you get the knack, it gets fairly easy."

"It was amazing how quickly they caught on and how good they have become," Gorlewicz said.
According to the graduate student, every time she meets with the students, they come up with new features that they would like her to add. The configuration that they think would be the most useful is a touch-sensitive version of the graphing calculators that are widely used by their sighted classmates.
"It would really help to have something like this because it makes us equal to everyone else," Kira said.

Provided by Vanderbilt University

POSITIVE PRELIMINARY RESULTS FROM PHASE 1b TRIAL OF QLT091001 IN SUBJECTS WITH RETINITIS PIGMENTOSA DUE TO RPE65 AND LRAT MUTATIONS

QLT Inc. has announced positive preliminary results from its international multi-center Phase 1b proof-of-concept clinical trial of QLT091001 for the treatment of Retinitis Pigmentosa (RP) due to inherited genetic mutations in retinal pigment epithelium protein 65 (RPE65) or lecithin:retinol acyltransferase (LRAT) (also known as early-onset RP). 

The Phase 1b study showed rapid, statistically significant and clinically meaningful changes in visual fields (VF) from baseline values, as well as improvements in visual acuity (VA), in the study of 17 RP subjects. In addition, small subsets of RP subjects were investigated for secondary effects on other key vision parameters impacted by RP, such as decreased retinal sensitivity, and the data available in these subsets showed notable and promising increases in average sensitivity levels. The single-course treatment data with QLT091001 represents the first stage of dose regimen testing as the basis for a longer term multiple course regimen in RP due to mutations in RPE65 and LRAT. 

RP is a disabling group of genetic eye diseases associated with progressive loss of vision including night blindness, constricted peripheral vision resulting in difficulties with daily activities, and in later life, reduced central vision, inability to read, and in many cases progression to severe blindness. RP can be caused by many different gene defects and symptoms can start at varying ages; patients with mutations in the RPE65 and LRAT genes tend to show vision loss very early in life (this type of RP is also known as early-onset RP).

In the open-label, multi-center Phase 1b clinical study, 17 subjects (ranging in age from 6 to 55 years, mean 29 years) with either RPE65 (12 subjects) or LRAT (5 subjects) mutations received a 40 mg/m2/day dose of QLT091001 once daily for seven days with post-treatment follow-up at 7, 14, and 30 days. Visual fields and visual acuity are key measures of clinically relevant visual function. VF was assessed using Goldmann Visual Fields (GVF) and VA was assessed using best-corrected visual acuity (BCVA, ETDRS letters); GVF maps were converted to assess the remaining functional retinal area for analysis. After a single 7-day course of treatment with QLT091001, the average retinal areas from baseline showed statistically significant improvements of 34% at day 7 (p=0.005), 29% at day 14 (p=0.02) and trended towards a statistically significant improvement of 23% at day 30 (p=0.07) in the evaluable subjects meeting GVF test criteria (n=14 subset). In the intent-to-treat (ITT; all subjects enrolled) analysis (n=17), the average retinal area from baseline improved by 22% at day 7 (p=0.03, statistically significant), 16% at day 14 (p=0.13) and 18% at day 30 (p=0.096). The evaluable subset of 14 subjects excludes three patients in the VF analysis because they did not meet criteria as determined by a third-party reader. Nine of 17 subjects (53%) showed an improvement in VA over baseline in at least one eye by greater than or equal to five ETDRS letters. 

Measurement of Goldmann Visual Field Improvement from Baseline
GVF analysis – retinal area	Day 7	Day 14	Day 30
Avg. increase from baseline – evaluable subjects (n=14) Avg. increase from baseline – ITT (n=17)	34% (p=0.005)* 22% (p=0.03)*	29% (p=0.02)* 16% (p=0.13)	23% (p=0.07) 18% (p=0.096)

(*statistically significant)

Following single-course treatment with QLT091001, the Retinitis Pigmentosa patients in the clinical trial experienced a rapid and significant improvement in certain visual function parameters, as per Dr. Hendrik Scholl of the Wilmer Eye Institute at Johns Hopkins University. He also added that the discovery of the genetic cause of retinal degeneration has revolutionized insight into disease processes at a molecular level and has given the physicians encouragement for potential therapeutic approaches.  

Baseline values in subjects showed a broad range of moderately to severely reduced visual acuities and visual fields. All subjects reported early onset of night blindness as one of the hallmarks of disease.

Additional tests included spectral-domain optical coherence tomography (OCT), full-field electroretinography (ERG), and quality of life assessments. Also, in small subsets of subjects, the effects of QLT091001 on several parameters of light sensitivity in dim light (night vision), pupillary reflexes, and responses of the visual cortex to potential changes in visual stimuli (functional magnetic resonance imaging, fMRI) were measured.

The fMRI substudy (n=2) showed activation of several previously quiet areas of the visual and parietal cerebral cortex after treatment. In addition, the substudy in dark adapted visual fields (n=2) showed a 16- fold average increase in sensitivity at 10%-50% of locations tested in each eye within days of the first dose. With longer dark adaptation, light sensitivity increases averaged 40-80-fold greater than baseline at 40%- 83% of the locations tested. Full-field sensitivity (FST) and pupillometry results supported the large increases in sensitivity in both eyes.

The additional secondary endpoints evaluated to date in this study support and are consistent with the changes in VF and VA observed following single course treatment with QLT091001.

Ongoing analysis of the safety profile of QLT091001 demonstrates a safety profile consistent with the Company’s Phase 1b study in patients with Leber Congenital Amaurosis (LCA). A retreatment study for the RP cohort has been initiated to assess the effects of repeat QLT091001 therapy in these patients. The database on this study remains open and further analyses of additional anatomic tests (OCT) and retinal sensitivity tests (ERG) are also ongoing to further explore the optimal baseline characteristics of responders for clinical development purposes.

The RP (early-onset RP) Phase 1b clinical study is being conducted at seven leading centers for the treatment of inherited retinal diseases in the U.S., Europe and Canada.

About Synthetic Retinoid Drugs
Genetic diseases in the eye such as Leber Congenital Amaurosis (LCA) and Retinitis Pigmentosa (RP) arise from gene mutations of enzymes or proteins required in the biochemistry of vision. QLT091001 is a replacement for 11-cis-retinal, which is an essential component of the retinoid-rhodopsin cycle and visual function, and is under investigation for the treatment of LCA and RP. QLT091001 has received orphan drug designations for the treatment of LCA and RP by the European Medicines Agency, and for the treatment of LCA and RP due to inherited mutations in the LRAT and RPE65 genes by the U.S. Food and Drug Administration (FDA). The drug has also been granted two Fast Track designations by the FDA for the treatment of the LRAT and RPE65 genetic mutations in both LCA and RP.

About Leber Congenital Amaurosis (LCA)
LCA is an inherited degenerative retinal disease characterized by abnormalities such as roving eye movements and sensitivity to light, and manifesting in severe vision loss from birth. Both rod and cone photoreceptors are affected in LCA. Eye examinations of infants with LCA reveal normal appearing retinas. However, a low level of retinal activity, measured by electroretinography, indicates very little visual function. According to current epidemiological estimates, LCA affects approximately one in 81,000 newborns worldwide, of which approximately 10% carry the inherited deficiencies of either RPE65 or LRAT.

About Retinitis Pigmentosa (RP) Due to RPE65 and LRAT Mutations
RP is a set of hereditary retinal diseases demonstrating clinical features similar to LCA. RP is also characterized by degeneration of rod and cone photoreceptors, but it presents with a more variable loss of vision in late childhood to adulthood. Deficits in dark adaptation and peripheral vision are particular hallmarks of RP. RP is currently estimated to affect at least 300,000 individuals worldwide, of which approximately 20%–30% are autosomal recessive (arRP). It is currently estimated that less than 3% of autosomal recessive RP patients carry the inherited deficiencies of either RPE65 or LRAT.

About QLT
QLT is a biotechnology company dedicated to the development and commercialization of innovative ocular products that address the unmet medical needs of patients and clinicians worldwide. We are focused on developing our synthetic retinoid program for the treatment of certain inherited retinal diseases, developing our proprietary punctal plug delivery system, as well as U.S. marketing of the commercial product Visudyne® for the treatment of wet age-related macular degeneration.

Derived from the press release from QLT Inc.