FDA committee sees Spark’s retinal dystrophy gene therapy as having favorable benefit-risk profile

Issue: November 10, 2017

An FDA advisory committee voted unanimously that Spark Therapeutics’ Luxturna gene therapy for retinal dystrophy has an overall favorable benefit-risk profile.

Sixteen members of the Cellular, Tissue, and Gene Therapies Advisory Committee voted yes and zero voted no, with zero abstentions, on the following question: Considering the efficacy and safety information provided in the briefing document, as well as the presentations and discussions during the AC meeting, does voretigene neparvovec have an overall favorable benefit-risk profile for the treatment of patients with vision loss due to confirmed biallelic RPE65 mutation-associated retinal dystrophy?

“I’d like to make one important comment about the issue that we’re addressing in terms of marketing approval of a therapeutic strategy for any disease, or in particular a rare disease. This important continuum exists between innovation and academic health centers that are initially federally funded, ultimately privately funded activities that lead to availability of the product for a wider population and change clinical practice. That’s really the goal at the end of the day, to make sure these products are available for the patients who need them. That’s what we heard during the open public hearing. This is really an important part of this value continuum of this type of personalized medicine,” Barry J. Byrne, MD, PhD, of the Powell Gene Therapy Center and acting chair of the committee, said.

Voretigene neparvovec, with the proposed trade name of Luxturna, is an investigational, potential one-time gene therapy candidate. The therapy is administered one time per eye in patients with vision loss due to the RPE65 mutation, according to a statement from Spark Therapeutics.

In a phase 3 clinical trial of Luxturna, results showed a statistically significant difference between 21 intervention patients and 10 control patients mean bilateral multi-luminance mobility testing change score of 1.6 at 1-year follow-up (P = .001).

“As a statistician, when I look at the data I like to see if the data tells us a story. The nice thing about this data is that it seems like everything fell together at the same way. It wasn’t that you had one endpoint that was significant and then everything else was either marginal or not significant and then it was hard to understand. It seemed like everything made sense in the same way, and that was very reassuring. I did some other statistical analyses on my own to see if everything would hold up, and it did hold up. I think they did the right analyses, and they were very strong analyses,” Sally Hunsberger, PhD, of Biostatistics Research Branch, National Institute of Allergy and Immunology, said before voting.

“We at Spark Therapeutics were delighted that the FDA Cell, Tissue, and Gene Therapy Advisory Committee unanimously endorsed the overall favorable benefit-risk profile of voretigene neparvovec for the treatment of vision loss in patients with confirmed biallelic RPE65 mutation-associated retinal dystrophy. We are grateful to the FDA, which put together a panel with expertise in a whole range of disciplines critical to successful ophthalmic gene therapy, including adeno-associated viral (AAV) vector design and manufacture, genetics, immunology, inherited retinal dystrophies, vitreoretinal surgery and biostatistics. This is an important step in the journey to successful licensing; we look forward to continuing to work with the FDA as they complete their review of voretigene,” Katherine A. High, MD, president and head of research and development for Spark Therapeutics, told Ocular Surgery News. – by Robert Linnehan

Reference:

FDA Cellular, Tissue and Gene Therapies Advisory Committee meeting; Oct. 12, 2017; Silver Spring, Md.