AVI Offers Glimmer of Hope for Muscular Dystrophy, Says UW Neuroscientist Jeff Chamberlain

some money to do a startup to do a Phase I trial of adeno-associated viral vector gene therapy for Duchenne Muscular Dystrophy. They’re starting already, and we’re hot on their heels. We’re going a little slower, because I think we’re focusing a little more on the safety. We saw an immune response to the vector when we tested it in dogs, so we’re testing the idea of temporarily blocking the immune system, and it’s showing tremendous progress.

X: You said the viral vector approach is showing better results in the mice than an antisense oligonucleotide like the one being used by AVI. Why all the excitement about that treatment then, if it’s not getting into the heart, if it’s not lasting more than a couple months, or prolonging lifespan?

JC: I think gene therapy is a more promising approach. But you don’t want to put all your eggs in one basket. It’s important to bring along as many possibilities in the hope that one will get in there and have a major impact on the disease. Second, conceptually, the antisense oligonucleotide approach is very simple. It can be manufactured at hopefully low expenses once you start mass-producing it. It doesn’t seem to require the extensive safety studies you need with gene therapy, because there is fear out there about conventional gene therapy. So it’s a viable approach, and it has shown promise in animals.

X: You’re not a clinician, so you don’t treat patients. What do you consider success five or 10 years down the road for these patients, in terms of life expectancy, quality of life?

JC: It’s always hard to put time frames around things. But I would say with the gene therapy approach that we’re working on here, I look at things through about a 10-year time frame.

I would like to specifically do a few things. One, I’d like to bring back some of the strength, maybe not all the strength. To maintain the ability to walk in young kids. And to have a dramatic expansion of lifespan. That’s what we’re shooting for. I don’t think you’ll ever necessarily have a cure for the disease. A cure to me, is to actually go in and correct the gene and have it be fixed. That’s the ultimate long-range goal for gene therapy.

X: So if your life expectancy is about 30 now, or in your late 20s, how high do you think that can go?

JC: About 10 years ago, the life expectancy was late teens or early 20s. Now we’re starting to push up towards 30.

X: What’s made that difference, given that we don’t have the gene therapy or the antisense that you’re talking about available yet?

JC: Two things. They are actually some simple things, surprisingly. These kids usually die

Author: Luke Timmerman

Luke is an award-winning journalist specializing in life sciences. He has served as national biotechnology editor for Xconomy and national biotechnology reporter for Bloomberg News. Luke got started covering life sciences at The Seattle Times, where he was the lead reporter on an investigation of doctors who leaked confidential information about clinical trials to investors. The story won the Scripps Howard National Journalism Award and several other national prizes. Luke holds a bachelor’s degree in journalism from the University of Wisconsin-Madison, and during the 2005-2006 academic year, he was a Knight Science Journalism Fellow at MIT.