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Gene Therapy Kids Update

Gene-carrying adeno-associated viruses with alterations to 10 amino acids in a single coat protein reached photoreceptors. (UC Berkeley)
Gene-carrying adeno-associated viruses with alterations to 10 amino acids in a single coat protein reached photoreceptors. (UC Berkeley)

Mid-June, I suspected that the media had picked up on something new in gene therapy when the Amazon rank for my book on the topic  (The Forever Fix: Gene Therapy and the Boy Who Saved It) plummeted – which is good. The rank isn’t the stars from readers, but a mysterious number assigned and designed by the Amazon gurus to distress authors. Each of 31 million or so books gets a number, with 1 the best. I’m thrilled if one of my books drops below 5 figures.

A BETTER WAY INTO THE EYE
My book is about a boy rescued from a sightless future thanks to gene therapy. Corey Haas has Leber congenital amaurosis type 2 (LCA2) — a form of the disease mentioned in the news that dropped my Amazon number. The news broke on June 12, the same day as the Supreme Court’s long-awaited DNA patent decision, which prompted a request from my blog editor to drop everything and write. Which I did.

When I returned to the gene therapy news, I was surprised that the national media had reported on work done in mice and monkeys, when people had already been helped with similar gene therapy. Then I read the paper in Science Translational Medicine. The coverage was well-deserved.

David Schaffer and John Flannery and their colleagues at the University of California at Berkeley and the University of Rochester developed a safer and faster way to send healing genes into the eye aboard a genetically diverse fleet of adeno-associated viruses (AAV). Their method may help people with more damaged retinas than the few dozen LCA2 patients who’ve had successful gene therapy because their retinas were relatively intact.

Instead of injecting the gene-carrying viruses beneath the retina as in the LCA2 method, which can detach it, the new approach sends the viruses into the vitreous humor, the fluid that makes up most of the eyeball. The viruses easily reach the most densely-packed, sequestered photoreceptors. “It’s a 15-minute procedure, and you can likely go home that day,” said Dr. Schaffer in a UC Berkeley news release. Plus, the technique may be applied to other remote anatomical sites.

Injecting AAV into the vitreous humor.
Injecting AAV into the vitreous humor. (UC Berkeley)

 

The new gene delivery method led me to wonder what happens when a clinical trial reaches phase 3, as is happening for LCA2, with safety and efficacy demonstrated and the numbers building, and then something that might be better comes along – even if it’s in mice and monkeys. I’ll leave it to readers to comment.

Coincidentally, just when gene therapy made a fleeting appearance in the news, I heard updates on some of the children from my book and who have been featured here.

HANNAH’S HOPE AND TAYLOR’S TALE

Lori and Hannah Sames (Dr. Wendy Josephs)
Lori and Hannah Sames (Dr. Wendy Josephs)

Also on June 12, Lori and Matt Sames addressed the Recombinant DNA Advisory Committee at the National Institutes of Health (NIH) in Bethesda. It was the first of three regulatory hurdles they needed to vault in their multi-year quest to start a gene therapy trial for giant axonal neuropathy (GAN) .

“My 9-year-old daughter Hannah asked me if she would die from GAN,” said Matt, close to tears, before the committee. “And I told her no.” Lori, who should have been awarded a PhD by now for her mastery of neurogenetics and clinical trial protocols, updated the committee on the natural history study and details of the vector delivery. The technical details faded when she said, suddenly subdued, “We all know what happens to these kids if we do nothing.”

The RAC gave a go-ahead, and so the gene therapy that was developed at the University of North Carolina and will be administered at the NIH Clinical Center may begin by the end of the year, if the protocol passes the next two hurdles: the institutional review board and FDA.

Meanwhile, Hannah’s disease is progressing, slowly. She has difficulty walking, and her vision is beginning to fade, her voice change. Hannah will only be in the clinical trial that her parents have gotten off the ground if her immune system can be sufficiently suppressed to ignore the protein that new genes will make in her spinal cord.

Following Lori on June 12 at the RAC meeting was Sharon King, advocating for her daughter Taylor, who has Batten disease. (Taylor’s sister Laura guest posted recently.) Taylor’s gene therapy will be possible because of the GAN project, using the same teams of viruses and researchers. That’s the way things work in the rare disease community – a victory for one is a victory for all, because the same delivery methods can work for different diseases. Thankfully, pharmaceutical companies are starting to recognize this.

A BROTHER’S LOVE

Max and Alex Randell.
Max and Alex Randell.

Ten-year-old Alex Randell will one day be a neuroscientist, so he can help people with Canavan Disease – like his brother, Max. I’ve been writing about the Randell family in my human genetics textbook since Max was 3 – he’ll turn 16 in October. Most kids with the neurodegenerative brain disease don’t live that long, but Max had gene therapy, twice. And he’s happy and adored, able to communicate with facial expressions.

On May 28, Alex told Max’s story at the NIH and asked for funding for research into treating Canavan disease. A DNA Science entry from December tells their story.

BACK TO THE EYE

Corey Haas will turn 13 in September. Without the two gene therapies, his worse left eye first, he would be living in a darkening world, headed for certain blindness.

8 Corey on bedInstead, Corey is enjoying summer at his home in Hadley, New York, a small town that hugs the Hudson about a half hour drive from my home. He lives in an area where nature rules, where city kids come for summer camp. Shares Corey’s mom Nancy, “Corey is doing very well. He got his turkey license, and was able to shoot at 3 toms, but missed….he’ll be going to a fishing camp, and he’s really excited.” Obviously, he’s seeing okay, and need only check in with the gene therapy folks at Children’s Hospital of Philadelphia (CHOP) once a year.

Meanwhile, at CHOP, at least two dozen others with LCA2 are signing up for the phase 3 clinical trial that’s underway, the youngest participant just 3 years old.

The Kabaali family from the Netherlands will visit Dr. Jean Bennett and her colleagues at CHOP in August, when 6-year-old Ceylin and her 4-year-old brother will be evaluated for the clinical trial. Their paternal grandfather was blind from the disease, but he lived in a small village in Turkey and had never been diagnosed.

On June 20, the mother posted on Facebook, “Philadelphia, here we come!” I can’t capture the hope and joy that overwhelms a family when medical science has a possible solution to their personal nightmare, so I’ll let her finish this post.

“I’m feeling very excited, happy, nervous, scared all at once…it’s all surreal. We have been waiting for this moment ever since we heard my daughter has LCA…that’s about 5 years ago….and now everything is going so fast. Things you think aren’t possible at first, can become true. Hopefully this will be so with gene therapy for LCA.”

Discussion
  1. Since Ricki just touched upon the discovery by Dr. Schaffer and Flannery at UC Berkeley about the new, safer virus delivery system, if you would like to read more, please take a look at my writeup in my Journal:

    A New Virus Vector for Safer Delivery of Gene Therapies in Ophthalmology

    Researchers at UCal Berkeley have found a gene therapy vector that can deliver genes deep into the retina via intravitreous delivery, instead of using a needle to deliver the virus sub-retinally.

    This eliminates the need for a vitrectomy, anesthesia and a hospital stay to treat patients, allowing for a simple short office visit and injection into the vitreous, similar to the way anti-VEGF drugs for age-related macular degeneration are currently delivered.

    To read more, please follow this link: http://tinyurl.com/GeneTherapy19

  2. Not a comment – just a quick question having recently heard your interview on “Quirks and Quarks” – Can Colobomas be treated using Gene Therapy – if not now in the near future ?

  3. I’m not an eye expert, but a coloboma is missing material, so gene therapy might not be the best approach, because gene therapy corrects underlying instructions. However, at least one form of LCA has coloboma associated with it. I’m not sure how gene therapy would regenerate tissue — I don’t think it can. A stem cell therapy might make more sense. But you’d need to ask an ophthalmologist.

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