UK-based biopharmaceutical company NightstaRx (Nightstar) has initiated enrolment and dosing in a Phase I/II clinical trial of its gene therapy 'AAV- XLRPGR' for the treatment of patients with X-linked retinitis pigmentosa (XLRP).
The gene therapy utilises a viral vector known as adeno-associated virus (AAV) to deliver a codon-optimised copy of the retinitis pigmentosa GTPase regulator (RPGR) gene into cells of the eye.
The multi-centre, open-label, dose-escalation Phase I/II trial will evaluate the safety and tolerability of AAV- XLRPGR over a 12 month period in approximately 24 patients enrolled at ophthalmology centres such as Oxford and Manchester.
Nightstar chief executive officer David Fellows said: “We are thrilled to report the advancement into the clinic of our second lead retinal dystrophy programme. If successful, this gene therapy has the potential of transforming the lives of many patients.”
Each subject will be administered a single sub-retinal injection of AAV-XLRPGR gene therapy.
University of Oxford ophthalmology professor and the trial's principal investigator Robert MacLaren said: "X-linked retinitis pigmentosa is a devastating disease of early onset, which leads to blindness in males.
"Many individuals are legally blind in their teens, and there is currently no treatment available.
"The unique codon-optimisation strategy overcomes the inherent instability problems of RPGR that confounded earlier attempts at gene replacement.”
Based on the results from previous studies in pre-clinical in vivo disease models, it is expected that this therapy can restore or maintain sight in patients.
Spun-out from the University of Oxford in 2014, Nightstar primarily develops therapies for retinal dystrophies.