News Release

NightstaRx Reports Long-Term Benefits of Gene Therapy for Inherited Form of Progressive Blindness, as Published in the New England Journal of Medicine

April 28, 2016

Findings Show That 5 Patients Receiving the Full-Dose of Therapy Experienced Sustained or Improved Vision in the Treated Eye for the Extent of Post-Treatment Follow-Up (up to 3.5 Years)

Two Patients Achieved a Significant, Long-Term Improvement in Visual Acuity of Greater than 3 Lines on an Eye Chart

London, 28 April 2016 – NightstaRx Ltd (“Nightstar”), a biopharmaceutical company specialising in developing gene therapies for inherited retinal dystrophies, today announced the publication from the University of Oxford of promising clinical results and long-term benefits of choroideremia gene therapy in this week’s issue of the New England Journal of Medicine (NEJM)*. Nightstar is now developing this gene therapy approach and the viral vector known as adeno-associated virus 2 (AAV2) to deliver a copy of the gene encoding Rab-escort protein 1 (REP-1) gene, the mutation of which leads to damage of retinal cells of patients with choroideremia, an inherited form of progressive blindness.

The study enrolled 6 patients with choroideremia at the University of Oxford’s Nuffield Laboratory of Ophthalmology under principal investigator Professor Robert MacLaren. As published in the NEJM, the clinical research findings demonstrated that 5 patients who received the full dose of AAV2-REP1 treatment maintained or improved vision in their treated eye for the extent of post-treatment observation (up to 3.5 years). In two patients, a significant improvement in vision of greater than 3 lines on an eye chart was sustained to the last time point reached. In the untreated eyes, vision declined in 5 out of the 6 patients at 3.5 years.

David Fellows, CEO of Nightstar said:

“Our mission is to maintain sight in patients suffering from a range of untreatable blinding diseases and the data published in the NEJM demonstrates that the effects of gene therapy are durable and could provide a single treatment for many types of inherited retinal dystrophies.”

Mr. Fellows continued:

“We are continuing to advance our AAV2-REP1 program in clinical trials and concurrently moving forward on two other gene therapy programs for sight threatening diseases in the retina.”

Robert MacLaren, Professor of Ophthalmology at the University of Oxford commented:

“Gene therapy has huge potential as a treatment for many patients who are suffering from inherited retinal dystrophies. Although there have recently been questions about the long-term impact of certain gene therapy regimens, we believe we now have strong validation of sustained, long-term efficacy following a single injection of the AAV2-REP1 viral vector.”


Further information:


David Fellows +44 (0) 20 7611 2048

JW Communications

Julia Wilson +44 (0) 781 8430877

About Choroideremia

Choroideremia is an inherited X-linked recessive disease which inevitably causes blindness. It is caused by mutations to the CHM gene which encodes Rab-escort protein 1 and affects approximately 1 in 50,000 people. The first symptom of the condition is usually an impairment of night vision which often occurs in early childhood. This is followed by progressive narrowing of the field of vision, as well as a decrease in the ability to see details, culminating in blindness, most commonly in late adulthood. No effective treatment currently exists. For patients interested in participating in choroideremia trials please follow this link:

About Nightstar

Nightstar is a private biopharmaceutical company, spun-out from the University of Oxford in 2014, focused on the development of therapies for retinal dystrophies. The Company’s lead programme is a retinal gene therapy for choroideremia, a rare inherited cause of blindness that affects around 1 in 50,000 people. The Company’s lead investors are Syncona LLP, a healthcare investment company, taking an active role in identifying, developing and funding technologies with the potential to significantly impact the healthcare market of the future and NEA, a global venture capital firm focused on helping entrepreneurs build transformational businesses across multiple stages, sectors and geographies.