Our Turn is Coming

Happy Monday! Waiting for the van again so forgive me if I run off abruptly.

Back to the pink of health. I revised my evaluation and decided it was food poisoning….again?!?! My dining companion ate her leftovers and also got sick as the proverbial dog.

I was well enough yesterday to accept an invitation to go kayaking. Said if before, say it again, weird weather. There was some guy jet skiing on October 16th! Anyway, it was fantastic to be on the river. Warm breeze. Birds calling. Fishermen shouting greetings across the water. Kids on the bank asking me if it were nice out there. Yeah. It was. Really nice.

To business! I promised you RPE65. The Genetic Home Reference tells us RPE65 is also called retinoid isomerhydrolase. Yeah, whatever. RPE65. RPE65 is responsible for providing instructions for a protein we need to see. It is, obviously, part of the RPE layer.

As I said last time, RPE65 is essential in the visual cycle. Light changes a special molecule called 11-cis into a different substance. Since it is no longer any good for changing light into electricity in its new form, it has to be ‘recharged’ so it can go back to work. That is the job of RPE65.

With me so far?

Failure to convert the end product of the reaction – referred to as all-trans-retinal – leads to a build-up of said all-trans retinal as a waste product and a toxin. In my terminology, it is part of the eye poop. Your visual cycle also stops working. Not good.

Now, I am not saying we AMD folks have problems with faulty RPE65 genes. (Although we might. I am only a dabbler in the field.) Those mutations are found in diseases like Leber congenital amaurosis (LCA) and retinitis pigmentosa (RP). What I am saying is every breakthrough in one aspect of vision research might lead to breakthroughs in other areas and – drum roll please! – there has been a breakthrough!

Not all that far away from me, in the City of Brotherly Love, also known to us country folk as ‘Filthydelphia’, Philadelphia to all you other folks, they have found a way to ‘reprogram’ faulty RPE65 genes using gene therapy. Philadelphia is on a roll because this is the second gene therapy its researchers have had recommended for approval. That is the second of two, mind you, EVER recommended for approval by the FDA. Philly researchers have gotten them both. One more and they will have a hat trick! (Go, Flyers!….OK, so their decades were the 1970s, ’80s and ’90s, but it could happen again.)

The first gene therapy recommended for approval was for leukemia. The visual cycle gene therapy is called Luxerna. It is going to be offered to children with early onset blindness in a bid to keep their photoreceptors functional. It has a very high success rate and is still working in phase 1 subjects from four years ago! [click here for an article that talks about this in more detail.]

So what happens now? Luxerna has been cleared to take the final hurdles. According to FDA.gov there are three more steps in a 12 step process. These steps are as follows: review of labeling information, inspection of manufacturing sites, APPROVAL.

Brave New World. Stay tuned. Our turn is coming.

written October 16th, 2017 Continue reading “Our Turn is Coming”

Ratings

  • Rate this
  • Summary
Current Average Ratings
Overall quality
Avg: 5.00/5
Applies to topic
Avg: 5.00/5
Helpful to me
Avg: 5.00/5
Our Turn is Coming
Total Avg Rating: 5.00 out of 5 with based on 1 rating(s)
Overall quality
Applies to topic
Helpful to me

Research: Dry & Wet AMD

Hello! I am going to get to the article Lin found on BrightFocus Foundation’s website about ‘lamp stuff’ aka lampalizumab but first I wanted to quickly mention a Google Talk by Isaac Lidsky. The title is Eyes Wide Open.

Lidsky began losing his sight to retinitis pigmentosa when he was 13 years of age. Although he has been totally blind for many years, Isaac Lidsky is extremely accomplished and has developed a philosophy that includes all sorts of concepts such as being present in the moment, doing what works and not abdicating responsibility for your life to your personal heroes and villains. His half an hour Google Talk may make some people rethink their attitudes towards their sight losses.

While I don’t expect many people to feel ‘lucky’ they are going blind – and Lidsky does consider his blindness to have been a blessing – Lidsky’s perspective on things can be thought provoking.

OK, onward to ‘lamp stuff’. We have quoted Joshua Dunaief before. One of the most helpful things he does for me in the current article is give us a pronunciation guide for lampalizumab. It is lamp-uh-liz-you-mab. Sort of like “Lamp!…uh, Liz, you mad/b?” You know, what you say when you knock over Elizabeth’s favorite light.

We have gone over the study results already in these pages. Complement factor I variant folks got kickin’ results. The rest of us, not so much. A reason for genetic testing for us before we submit to needles in the eyes, literally!

Dunaief says results are expected in 2018. Yep, December is their target date for publication. He does not mention phase 3 is over this December as is indicated in clinicaltrials.gov.

So, basically, still not really sure what is happening with ‘lamp stuff’ and me. May be offered it in December. May not be. May accept the offer. May not. I would love to know my genotype as compared to the SNPs they found in the experimental sample. Being a responder would be incredible. Being a nonresponder would be very bad. Dilemma.

And information for our ‘wet’ friends for my last 200 words. In JAMA Ophthalmology Jackson, Boyer and Brown reported the results of an experiment with an ORALLY administered vascular endothelial growth factor (VEGF) inhibitor. In other words, they have been experimenting with a pill they hope would do the same thing as your anti-VEGF shots.

The stuff is a tyrosine kinase inhibitor. It caused a lot of upset tummies and diarrhea (5 and 6 subjects out of 35 respectively) but the side effects were not bad enough to stop the experiment. Some people did stop because of liver problems. Those with liver issues would probably not be candidates for the treatment.

Only 40% of the total required rescue shots. Even those people received fewer injections than they had without the pills.

Before you all rush out for your X-82 pills, bear in mind this was a phase 1 experiment. That is safety and tolerability, guys. They are moving on to proof of concept, phase 2, with a bigger n. (n being the number of subjects in the study, remember). Check clinicaltrials.gov if you are interested.

Remember we all do our part in this fight. If you have a strong liver and a strong stomach, X-82 might be your kind of research. You might get to be a lab rat before I do!

written September 2nd, 2017

Continue reading “Research: Dry & Wet AMD”

Ratings

  • Rate this
  • Summary
Current Average Ratings
Overall quality
Avg: 0/5
Applies to topic
Avg: 0/5
Helpful to me
Avg: 0/5
Research: Dry & Wet AMD
Total Avg Rating: 0.00 out of 5 with based on 0 rating(s)
Overall quality
Applies to topic
Helpful to me

The Winner Is…Genetics!

I just tried to read the article listing the different genetic variants that have been associated with AMD. The complementary system in Age-Related Macular Degeneration: A review of rare genetic variants and implications for personalized treatment is declared the winner!

I admit defeat! Maybe I can study genetics for a decade and come back for a rematch.

I can sum up what I learned in about two sentences. The great majority of SNPs associated with AMD appear to be on chromosome 1 where the complement immune system is coded. SNPs cluster around the location of Complement Factor H although there are also large numbers of mistakes in the neighborhoods of Complement Factors i,2,3,9 and B.

The second thing I learned is this: the rare forms of AMD are coded for in other places. These ‘outliers’ are being studied in genetically-isolated groups such as the Amish.

Side note: The Amish are a closed, religious and cultural sect. Pennsylvania is a population center for the Amish. Therefore, here in Pennsylvania they live in association with us although not necessarily among us.

The Amish have all descended from an initial group of about 200 families. Because of the close inbreeding they suffer from a variety of genetically based problems such as dwarfism, Angelman’s Syndrome and several metabolic disorders. Being such a ‘natural laboratory’ for study of the founder effect, the Amish have allowed much genetic testing on members of their community. One of the conditions studied? Age-Related Macular Degeneration.

For more information on the Amish, check Wikipedia or your favorite reference.

OK, so it is not strictly info on AMD, but man does not live by vision loss news alone. I find that sort of stuff interesting. Hope you do, too.

And quickly back to the AMD stuff – because I only have about 200 words left – the Audacious Goals Initiative is still working hard to stamp out blindness. I found a better article on the mouse-zebrafish experiments on their page at the National Eye Institute. This article stressed how the Muller glia cells from the zebrafish had been able to be transformed so beautifully they were electrophysiological indistinguishable from interneurons cells. They had integrated well on both ends of the connection required and were sending signals to the brain. In other words, the zebrafish cells had changed and connected so the blind mice could now see.

Very preliminary work but exciting. The article cites a lot of problems such as: there are not quite enough zebrafish eyes to satisfy the demands of potential research. It might be best to find ways of coaxing regeneration of existing cells in our own eyes. Save the zebrafish!; you understand.

Just one more amazing bit of research and discovery that some day will eliminate Age-Related Macular Degeneration and allow people to see….I’m just glad there are people out there who are a helluva lot smarter than I am to do the research. Now, anyone want to explain the genetics to me?

written August 27th, 2017

Continue reading “The Winner Is…Genetics!”

Ratings

  • Rate this
  • Summary
Current Average Ratings
Overall quality
Avg: 0/5
Applies to topic
Avg: 0/5
Helpful to me
Avg: 0/5
The Winner Is…Genetics!
Total Avg Rating: 0.00 out of 5 with based on 0 rating(s)
Overall quality
Applies to topic
Helpful to me

Another Potential Treatment

The more I look into this, the more overwhelming it seems! I am glad I never tried to be a geneticist!

What am I talking about? The latest information on treatment for geographic atrophy suggests there is another gene being targeted. The gene is C3.

Remember how I have been saying Age-Related Macular Degeneration is looking not like one disease but like a family of diseases? When I followed up with some background research on complement factor C3, I found a list of – get this – over 3 dozen different SNPs that preliminary evidence suggests have a role in causing AMD. Remember SNPs or ‘snips’ are genetic coding errors. Some are beneficial. Some are neutral and some can really screw thing up.

Anyway, it appears there are literally dozens – if not more – of ways we can be ‘wrong’ to get AMD. Right now that means they are working on finding dozens of ways to intervene. May be a panacea sometime in the future, but right now they are nibbling at the problem a piece at a time.

And the piece they are nibbling on now is C3. According to a short article by FierceBiotech, Apellis has finished phase 2 – the proof of concept phase – trials with intravitreal injections of a drug they are calling APL-2. Later it will get a trendy brand name but for now look for APL-2.

BusinessWire identifies Apellis as a company “developing a platform of novel therapeutic compounds for the treatment of autoimmune diseases” so I guess people are coming around to see AMD as an autoimmune disease. APL-2 is described as a complement factor C inhibitor. It “binds specifically to C3 and C3b, effectively blocking all three pathways of complement activation (classic, lectin and alternative).” That sort of sounds like it is suppressing ‘friendly fire’ sooner in the process and may be closer to the ‘one treatment fits all’ that we would like to see. Not anywhere near there, but closer.

The results were very promising. At 12 months they showed a 29% reduction in growth as compared to sham.

But the weird – and great! – thing that happened was this: during the second six months of the study, the reduction rate was 47%! For some reason, the effects of the treatment appeared to be cumulative. Pretty cool.

Now I am not sure what type of genotype you have to have to profit from treatment with APL-2. The researchers are not sure at this point either. They decided to do some searching for genetic markers. Being the suspicious sort, I am wondering if they had star responders and non-responders just like they did with lampalizumab. Would make sense. Why do genetic testing on an ‘n’ of 246 people if you don’t have to? It’s expensive.

And speaking about money, there is a lot of money to be made with this drug. Apellis wants to get APL-2 to market quickly so it can compete with eculizumab, a treatment for PNH, a blood disease. (Apparently PNH is also related to complement factor C). Their competition, Soliris, was predicted to bring in more than $3 billion in 2017. Sometimes a little greed is a good thing! $3 billion can really motivated people.

So, there you go. It seems they have found one more way to save some of the sight of some of the people some of the time. Number two potential treatment for our ‘untreatable’ disease. The wall is coming down a brick at a time. There is hope.


Here’s another article about APL-2 that says “APL-2, a complement C3 inhibitor, has met its primary endpoint in its phase 2 clinical trial, reducing the rate of geographic atrophy (GA) associated with age-related macular degeneration (AMD).”

written August 27th, 2017 Continue reading “Another Potential Treatment”

Ratings

  • Rate this
  • Summary
Current Average Ratings
Overall quality
Avg: 0/5
Applies to topic
Avg: 0/5
Helpful to me
Avg: 0/5
Another Potential Treatment
Total Avg Rating: 0.00 out of 5 with based on 0 rating(s)
Overall quality
Applies to topic
Helpful to me

Genetics of AMD

Genetic Rant & Roll – The Miniseries

Home

 

Ratings

  • Rate this
  • Summary
Current Average Ratings
Overall quality
Avg: 0/5
Applies to topic
Avg: 0/5
Helpful to me
Avg: 0/5
Genetics of AMD
Total Avg Rating: 0.00 out of 5 with based on 0 rating(s)
Overall quality
Applies to topic
Helpful to me

Snips & Snails & Puppy Dog Tails

Snips and snails and puppy dog tails are supposed to be what little boys are made of. However, now it appears we girls are made of snips also!

Just when I had decided I am not appropriate for ‘lamp stuff’ (lampalizumab) because I do not have the complement factor I (CFI) at risk allele, Lin informed me the snips ArcticDX tested for are not the same ones as in the study! I may be saying I don’t qualify because I don’t have ‘fruit’ but Arctic tested for oranges and the researchers tested for apples. Apparently all ‘fruit’ was not created equal. My CFI test that was fine may not really have tested what should have been tested if I want to make a decision about the study. I am so confused! [Sue talks about CFI & lampalizumab in pages I Want to Be a Mutant and I Am Not a Mutant.]

So what in Hades am I talking about? See above. The part about being confused. Let us delve further into this mystery.

A snip is actually SNP (it is pronounced snip). That is a Single Nucleotide Polymorphism. SNPs are tiny, little parts of genes. They are a variation in the spelling of our genetic code. Clear as mud, right?

Let us try again. The alphabet of genetics is made up of four letters: A, C, G,and T. Each of them is a nucleotide. Vary the order of the nucleotides on an allele and you can get any one of a variety of characteristics being expressed. Life in all of its diversity is written with a four- letter alphabet.

Sometimes Nature doesn’t spell too well. Sometimes she gets sloppy and copies a C for an A or whatever. These spelling errors do not cause disease but they can affect how the cell will function. They can also predict a response to certain drugs.

Spelling errors or SNPs are very common. According to my source, the Genetics Home Reference again, any one of us can happily harbor 10 million SNPs. However, even with that number of errors, Mom Nature still earns top grades in spelling. 10 million letters in error is a drop in the bucket when you consider how many letters were written for each of us.

We have gone from chromosomes to genes to alleles to SNPs. We are getting smaller and more specific as we go. Pages to paragraphs to words to letters. The SNPs are letters in error in the book of Life. Apparently the genetic testing I had found no spelling errors at the top of a paragraph while the researchers found spelling errors at the bottom of the paragraph. These bottom of the paragraph spelling errors caused the fantastic response to ‘lamp stuff’.

Looking at the perfect spelling of words at the top of the paragraph cannot tell me if I harbor those magic mistakes at the bottom. I am back to where I was. Indecisive as to what to do once again.

written July 30, 2017 Continue reading “Snips & Snails & Puppy Dog Tails”

Ratings

  • Rate this
  • Summary
Current Average Ratings
Overall quality
Avg: 0/5
Applies to topic
Avg: 0/5
Helpful to me
Avg: 0/5
Snips & Snails & Puppy Dog Tails
Total Avg Rating: 0.00 out of 5 with based on 0 rating(s)
Overall quality
Applies to topic
Helpful to me

Re-educating Our DNA

Back to the Genetic Home Reference. I have been seeing things that say gene therapy is one possible avenue of treatment for AMD and I have not been too sure what it is.

The Genetic Home Reference says gene therapy is the replacing of a mutated gene that causes disease with a ‘good’ copy of the gene. It may be used to deactivate a problematic gene or be introduced to help to fight a disease.

Because it is a new and potentially dangerous field of exploration, gene therapy is limited to diseases and conditions with no, known cures. That’s us, guys.

If you are not familiar with viruses, I offer a quick tutorial on how they work. Viruses are barebones ‘life’. There is debate as to whether or not they even meet criteria for being considered living organisms. Part of the definition of a living organism is that it can reproduce its own kind. Viruses cannot do that. Since viruses are no more than a strand of DNA wrapped in protein, a virus must ‘hijack’ a cell to make little viruses. The baby viruses eventually kill the host cell. This is why we get sick when we have a virus. Our cells have become factories/hosts for baby viruses. Sort of like the movie Alien in miniature. Yuck.

Since viruses have the ability to pierce cell membranes and mess with the cell’s ability to reproduce – effectively ordering the cell to reproduce a slew of baby viruses – it was decided they would be perfect for introducing ‘replacement parts’ into defective cell DNA.

The name for something that transfers things from one organism to another is called a vector. Therefore gene therapy uses viral vectors to get new DNA into cells. Researchers replace the basic, virus DNA with genetic material it hopes will repair the defective genes, then it ‘launches’ the viral vector to ‘attack’ and ‘hijack’ the cell.

How this relates to AMD is sort of basic. We know AMD is a genetically based condition. Change our genetics and we may eliminate the disease.

Johns Hopkins researchers have completed a phase 1 clinical trial during which they ‘infected’ retina cells with a virus carrying a gene that would cause the retina cells to produce a protein that interferes with the signals leading to the growth of new veins. The goal is to genetically alter enough cells they will produce enough of the protein to totally halt the neovascularization process and eliminate the need for shots.

Of course these studies are in very early days. One of the problems encountered was many people have developed resistance to the viruses use. They had met these enemies (the protein in the sheaths of the viruses) before and their defenses were in place. If the vectors are destroyed before they get to the targets, they cannot very well plant the new gene.

Still early days on gene therapy but it most definitely has promise. Remedial instruction to ‘re-educate’ our DNA may be on the way.

written July 16th, 2017

Continue reading “Re-educating Our DNA”

Ratings

  • Rate this
  • Summary
Current Average Ratings
Overall quality
Avg: 0/5
Applies to topic
Avg: 0/5
Helpful to me
Avg: 0/5
Re-educating Our DNA
Total Avg Rating: 0.00 out of 5 with based on 0 rating(s)
Overall quality
Applies to topic
Helpful to me