LCA Gene Therapy Clinical Trials Update
january 2008
Remember when everyone was talking about those doctors who had found a way to "cure" LCA in dogs? We were all eagerly awaiting the clinical trials to begin in humans, but these things just seem to move so slowly! Well, we finally have some new news!
As you may have been following, the LCA gene therapy clinical trials were first approved in December of 2005. Before this approval, doctors had successfully used gene therapy to restore sight in dogs who were diagnosed with LCA. This was very promising and they were eager to try the same approach on a human model. You can read more about the approval and the dog trials here.
Nearly two years later, in October 2007, they were finally able to begin the first clinical trial on a human. That human, Billy, introduced himself to the LCA email group on December 20, 2007 and was gracious enough to accept our bombardment of questions. Below are our questions and Billy's answers...
Tell us a little about yourself.
My name is Billy and I'm from Spartanburg, South Carolina which is in thenorthern part of SC. I am currently going to school for a B.A. in ComputerScience. I have worked in 911 communications services as I.T. Director andTelecommunicator. I am turning 25 tomorrow.
How long has it been since you received treatment in the trial?
I received it on October 18, 2007 at about 9:30 am.
Can you describe your vision before the trial began? Did you seebetter as a child? Has your vision gotten worse as you've gottenolder?
Before the trial I could see well enough to read size 12 font in highcontrast on the computer. I am one of the rare few who have had pretty goodeyes from birth on. I can see well enough to do mostthings except drive. I could almost drive just not legally.
Why are they choosing patients with so much usable vision? Could patients with less vision still be helped by the therapy?
See, the damage is done in LCA early on and the gene transfer will still fixthe genetic problem but not regrow cells, BUT the next part of it will befixed with stem cells.
Are you experiencing any changes in vision yet?
Yes, in a sense. I do now have brighter flashes of light in that eyethat I did not have before. I can see 20/200 in my right eye. They did the surgery on the left. The visual acuity in the left eye actually dropped from 20/200 to 20/400. I was told this should be temporary. So some minorimprovement in light could be considered as an improvement but the drop inacuity is not good.
Did you experience any pain? Have you had any adverse reactions at all?
Not really other than what I mentioned above.
I'm surprised to hear your vision actually decreased after you receivedgene therapy. You said they told you it would be temporary. So was thatexpected? Did they explain why?
Well, yes it did decline, but they still stand by the procedure right now.This trial is mainly for safety concerns. The reason for the decline is theway the injection takes place. I am going to explain exactly how it is done.
On Surgery Day they take you down to the OR and prep you early in themorning. They had me on IV fluid for use during the surgery. When I gotready for the surgery they moved me to the operating table and talked methrough each thing they were doing. They put everything over my face neededfor the procedure to be sterile. Next, they temporarily knocked me out andmade the first incision into the eye which would be used to numb the eye andmake it stable. They woke me back up and started sticking the other 2needles in. 1 for pumping eye fluid in and out. This is done to keep eyepressure stable. The other needle is used for injecting the vector.
Now, when they go to inject the vector they make a small retina detachment.This is where the long term affects come in. If any of you care to look atretina detachments you will see that it takes quite a long time to heal. Ican say they told me that it is only to affect 5-10% of my area of goodvision.
Today I am noticing some more brightness.
The needles sound very scary. Did they have to stabilize your eyes?All I can think is that I would definitely blink!
It was not that scary. Yes, they did stabilize my eye. Theyput a sterile tape over my head with a little table over my face withonly one hole for the eye having the procedure. I couldn't see out of theother eye because the table covered it. They numbed my eye and I barelyfelt anything except a little pressure from the needle, but not pain.
I just have a question about the retinal detachment. You were saying that the doctors said it would affect 5-10 percent of your vision? Does this mean that they meant you would loose that amount of your pre-trial vision due to the detachment temporarily or for good?
Well from what they told me I gathered that they meant if it went either way it would be about 10%. In order for them to inject the material they have tocreate a very small retinal detachment. I have brighter light levels now,but it is still blurry. I had vision enough to read large print out of thiseye before surgery, but now I don't. I personally think it is a time issueright now. Just waiting and hopefully seeing better. I think I may haveincreased night vision more than anything.
How long did they say it would beuntil you reach full potential from the procedure?
Since this is the first time this has been done there are so many unknownssuch as how long it may take for it to work or not work. Originally it was4-6 weeks, but we have surpassed that.
Did you indeed stay in Florida for three weeks? Was it as boring as Dr. Jacobson promised?
Yes, it was pretty boring. I had to come up with ways to spend my time. Imainly sat and watched TV and played on the internet. Dr. Jacobson is veryselective in the way he does things which is ok. I know he is very smart. Ilove talking to them. I loving learning what is going on and how these testswork. I have been very lucky to have a lot of this stuff explained to me. Byfar it was an interesting experience.
Is your treatment finished or is there more to go?
I will be heading to Philadelphia, PA to continue the checkups. No moreactual treatment is necessary for me at this time. If it does work then Iwill do the right eye in the next year.
Do you know howmany participants are in the trial?
Well, there is expected to be 8 or 9. No other person has had the procedureyet. I will have more details next Saturday when I return from Philly afterhaving the checkups. They were expecting to do another before Christmas butI don't think that has happened. I have a friend who may be in it in March.
Are you glad you participated?
Yes, for the most part. I am doing this for the younger generation. If I gain it would be a big plus, but if not, oh well, I hopethe kids of the future will.
We heard back from Billy in January 2008 after a recent trip to Philadelphia for a checkup with his doctors...
How was your latest checkup in December (2007)?
I spent the better part of Wednesdayafternoon through Friday afternoon doing my usual tests which include FSTand I dunno what all they are called. I arrived back home Saturday morningsafe and sound. The results from the past 2 visits are that it appears theremight be some POSITIVE growth of the cells in the retina. Still a littleearly though. The blurred vision I am experiencing could take 6 months to ayear before it fully comes back. The reason for this is the cones have tore-grow. I am still seeing better in dim lightin the operated eye.
Also, the 2nd participant has been operated on with no safetyconcerns. Because of confidentiality I am not able to find out more aboutthat person.
I certainly don't want to compare you to a dog, but as most of us know, the original trials like this were in dogs. Do they know if youor the other participants appear to be going the same direction asthat trial? Is it too early to tell, or are comparisons just noteasily made between animal and human trials?
I think that it is a little difficult to compare but I believe it is taking humansa little bit longer to obtain the transfer. Also the dogs stayed in completedarkness and we humans just can't do that so they think light may slow the process.
I think that it is a little difficult to compare but I believe it is taking humansa little bit longer to obtain the transfer. Also the dogs stayed in completedarkness and we humans just can't do that so they think light may slow the process.