A gene therapy for an inherited eye disease developed by Nightstar Therapeutics has picked up a coveted designation from the FDA that could accelerate its development.
The RMAT (regenerative medicine advanced therapy) status has been given to NSR-REP1, the London-based biotech’s therapeutic for choroideremia, a rare, degenerative retinal disorder that mainly affects males and causes blindness.
RMAT status is analogous to breakthrough status for drugs but applies to cell therapies and – since November 2017 – has been open to gene therapies. It combines the benefits of the breakthrough and fast-track programmes, which include early interaction with the regulator to help therapies that could make a big difference to patients move swiftly through development and review. There is currently no treatment for choroideremia, which typically leads to vision loss in early adulthood.
“Receiving RMAT designation for NSR-REP1 highlights the potential of this gene therapy to maintain and improve visual acuity in choroideremia,” said Dave Fellows, Nightstar’s chief executive, adding that it “underscores a recognition of the serious nature of choroideremia and the urgent need to develop new treatments for those affected by inherited retinal diseases.”
NSR-REP1 is already in a phase III trial intended to support approval which got underway in March and is expected to enrol around 140 patients who will receive direct injections of the therapy into one eye and compared to a group with no treatment. The study is due to report results in 2020.
Nightstar’s gene therapy – which uses an adeno-associated virus (AAV) vector to deliver the REP1 protein missing in choroideremia patients – has already generated positive results in a phase1/2 data which showed it was able to maintain or improve visual acuity over a one-year follow-up period in 90% of patients.
Last month, FDA Commissioner Scott Gottlieb told the Alliance for Regenerative Medicine in the US that the RMAT designation is a key part of its plans to help bring forward cell and gene therapies. The agency will be publishing a framework soon to address “manufacturing issues and the development pathway for gene therapy products.”
As of the end of April of this year there had been 62 RMAT designation submissions since the start of the programme in December of 2016, and 19 designations had been granted.
The pace of gene therapy development has been “somewhat breathtaking,” said Gottlieb, who alluded to a report suggesting 40 gene therapies could be approved for marketing in the US by the end of 2022, with 45% in cancer. It’s a bold prediction given that just one – Spark’s hereditary retinal dystrophy therapy Luxturna – has been registered so far.
“FDA has more than 500 active investigational new drug applications involving gene therapy products,” he told the ARM meeting. “We’ve received more than one hundred such applications last year alone. This shows the intensity of scientific work going on in this field.”