Gene Therapy restoring sight

[roni]

To some children with a particularly early onset version of the disease Kathy has

Breaking News from the Foundation Fighting Blindness

04/28/2008
Now They See
Landmark Gene Therapy Provides Vision to Nearly Blind Young Adults


Jean Bennett, M.D., Ph.D.,
lead investigator of the study, with her husband, Albert Maguire, M.D.,
the study’s lead surgeon.
Three young adults with virtually no vision can now read several lines on an eye chart and see better in dimly lit settings thanks to an innovative gene therapy aiming to reverse blindness in a severe form of retinitis pigmentosa known as Leber congenital amaurosis or LCA. One person was even able to better navigate an obstacle course several weeks after receiving the therapy.

The three individuals are participating in a Phase I clinical trial at The Children’s Hospital of Philadelphia, which is funded in part by the Foundation Fighting Blindness.

“I am overwhelmed with delight. We are delivering vision to people who were blind. This is the biggest advancement in the 37-year history of the Foundation Fighting Blindness,” says Gordon Gund, Co-Founder and Chairman of the Foundation Fighting Blindness. “We have achieved an incredible milestone in curing blindness, and this advancement will help pave the way for the development of gene therapies to treat and cure a variety of retinal diseases including: retinitis pigmentosa, Stargardt disease, Usher syndrome, and macular degeneration. This is a great day for the Foundation and all people affected by blinding retinal diseases.”

The development of the approach began when a form of LCA was linked to the RPE65 gene in 1997. Three years later, researchers began giving vision to dogs born blind from LCA, including the world-famous Lancelot. More than 50 dogs have been treated and all continue to see well. The Foundation Fighting Blindness has been funding this research virtually every step of the way.

Though the Phase I studies are primarily focused on safety, the first dose used in this study resulted in improved vision. An additional six individuals will be enrolled in a continuation of this study to evaluate safety and efficacy of differing doses. The vision improvement in young adults seen so far at the lowest dose gives researchers optimism that the treatment may provide near-normal vision to children in Phase II studies.

Results of the clinical trials, funded in part by the Foundation, were published on April 28, 2008 in the New England Journal of Medicine. The journal published the results of gene therapy trials taking place at CHOP and Moorfields Eye Hospital in London. A third trial of the gene therapy, sponsored by the NEI, is also taking place at the University of Pennsylvania and the University of Florida.

Jean Bennett, M.D., Ph.D., lead investigator of the CHOP trial, reports that the team studied three participants, who ranged in age from 19 to 26. All three had one eye treated.

Bennett says that all three individuals reported improved vision in dimly lit environments and in visual acuity in their injected eyes starting two weeks after treatment. Nystagmus — the roving eye movement associated with severe vision loss from LCA — was also reduced in all three individuals.

The treatment developed by this team of investigators involves delivery of a normal RPE65 gene to the retina to augment function of the defective RPE65 gene that leads to one form of LCA. Twelve different genes that lead to LCA have been identified.

The gene is delivered using a therapeutic virus known as an adeno-associated vector or AAV.

Researchers believe the vision improvement from a single injection will last for many years. In earlier laboratory studies, a single AAV-based gene therapy in more than 50 dogs born blind from LCA has been effective for more than seven years.

This study is being carried out by an international team led by The University of Pennsylvania, The Children’s Hospital of Philadelphia, the Second University of Naples and the Telethon Institute of Genetics and Medicine (both in Italy), and several other American institutions.

http://www.blindness.org/research.as...%204,%205,%206

[Kellyk]

Very interesting Roni.
Is that something that might possibly be able to help Kathy?

[louden48]

I saw something about this on tv this morning. What wonderful news and exciting research!

[Buggirl]

Ain't science amazing? What a wonderful gift to those children- here's hoping this will eventually become a broad-sweeping cure for blindness....

[roni]

Originally Posted by Kellyk

Very interesting Roni.
Is that something that might possibly be able to help Kathy?

Absolutely. Along with stem cell therapy, it is her only chance at a cure.

There is one thing in Phase II clinical trials that may help preserve what sight remains for people with genetic retinal disorders, it could not but does not have the potential for a cure, at this point.

[Tommygurl]

Hi Ron! I get updates from the Foundation Fighting Blindness! Encouraging news! Love you guys & I am so hoping there is a major breakthrough soon!

[TeeZet]

Originally Posted by roni

Absolutely. Along with stem cell therapy, it is her only chance at a cure.

There is one thing in Phase II clinical trials that may help preserve what sight remains for people with genetic retinal disorders, it could not but does not have the potential for a cure, at this point.

Speaking of stem cells, a major breakthrough was reported a few days ago (albeit in a different area of the human body):
Heart Derived Stem Cells Develop Into Heart Muscle

The Gene Therapy seems real encouraging, too.

Hopefully many people will benefit from those researches in the near future!

[roni]

Originally Posted by louden48

I saw something about this on tv this morning. What wonderful news and exciting research!

It is exciting!!

Originally Posted by Buggirl

Ain't science amazing? What a wonderful gift to those children- here's hoping this will eventually become a broad-sweeping cure for blindness....

I think we are going to be dumbfounded at some of the advances in the medical sciences over the next decade. There seems to be a lot in many areas of medicine where major advances are just around the corner

Originally Posted by Tommygurl

Hi Ron! I get updates from the Foundation Fighting Blindness! Encouraging news! Love you guys & I am so hoping there is a major breakthrough soon!

You're so nice. Kathy's doc (geneticist and retinal electro-physiologist) says, the way the disease if progressing she probably has another 8 years or so before legal blindness. That isn't as bad as being totally blind, but the impact is already being felt. She went somewhere yesterday and missed the last rush-hour bus home, so ended up getting her exercise in. Not being able to drive in a country that has relatively poor public transit is a drag.

Originally Posted by TeeZet

Speaking of stem cells, a major breakthrough was reported a few days ago (albeit in a different area of the human body):
Heart Derived Stem Cells Develop Into Heart Muscle

The Gene Therapy seems real encouraging, too.

Hopefully many people will benefit from those researches in the near future!

Thanks Tony. Stem cells offer the opportunity to replace lost photo-receptor cells (rods and cones). That would be amazing. The research is moving forward. Sometimes the pace seems slow, but it really is amazing.

[TeeZet]

Originally Posted by roni

... but it really is amazing.

Yes, it really is.
To think of what already has been achieved in the last couple of decades compared to the last couple of centuries!

[louden48]

Jeff has had many problems with his eyesight resulting from diabetes. He has had vitrectomies in both eyes and has great difficulty seing in low light situations. I don't think there is anything they can do at this point to improve his eyesight but I would love to see some research in this area. I am very encouraged by this news and glad that Kathy may possibly benefit from the current findings!

[BonnyW]

This is very good news.

[roni]

Originally Posted by BonnyW

This is very good news.

Pregnant with potential.
Hope the gestation period is not too long.

[roni]

Originally Posted by louden48

Jeff has had many problems with his eyesight resulting from diabetes. He has had vitrectomies in both eyes and has great difficulty seing in low light situations. I don't think there is anything they can do at this point to improve his eyesight but I would love to see some research in this area. I am very encouraged by this news and glad that Kathy may possibly benefit from the current findings!

I have diabetes also, but so far it is under control and the complications that can happen, like the eyesight thing, have not reared their ugly head much - yet.

I worry about that a little, and we joke about it some - it would be the blind leading the blind

[BonnyW]

Originally Posted by roni

Pregnant with potential.
Hope the gestation period is not too long.

Fruitful
So far only in the young'ins though, but with gene therapy, and a 'little' more' funding, who knows?
Any kind of breakthrough like this (and it is a big one) gets the 'community' talking about possible alternatives

[Babaloo]

More good news!

3 more blind patients helped by gene therapy
Virus delivered gene to eyes' light receptors in ongoing experiment

Reuters

WASHINGTON - Three more patients treated with an experimental gene therapy approach have reported better vision, U.S. researchers reported on Monday in a study that lends further support to the approach.

The patients, all in their early 20s, reported markedly better vision after getting the treatment, Artur Cideciyan and James Wilson of the University of Pennsylvania and colleagues reported.

"Day vision improvement could range up to 50-fold from pre-treatment levels. Night vision was quite dramatic and ranged up to 63,000 times" better, Cideciyan said in a telephone interview.


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