Allergan and Editas Medicine have launched a new Phase I/II clinical trial to assess CRISPR-based experimental medicine AGN-151587 (EDIT-101) for the treatment of Leber congenital amaurosis 10 (LCA10).

LCA10 is an inherited retinal disorder caused by mutations in the CEP290 gene that results in blindness.

AGN-151587 is to be given as a subretinal injection and has been designed to reach and directly deliver gene-editing treatment to photoreceptor cells.

The trial, named Brilliance, will involve an in-vivo process where genome editing occurs within the human body.

It will evaluate the tolerability and efficacy of AGN-151587 in around 18 participants, who will be randomised into up to five cohorts across three dose levels.

The open-label, ascending dose study will be performed at several sites, with centres in the US having already started enrolment.

Adults and paediatric patients aged three to 17 with a range of vision will be recruited. A single dose, subretinal injection of AGN-151587 will be given in one eye after vitrectomy.

Allergan chief research and development officer David Nicholson said: “Beginning patient enrolment in the AGN-151587 clinical trial with our partners at Editas is an important step toward our goal of developing a game-changing, transformative, CRISPR-based medicine for people with LCA10.”

Primary outcome measures of the Brilliance trial are the frequency of drug-related adverse events, the number of patients with procedural related adverse events, and the incidence of dose-limiting toxicities.

The study will also measure secondary outcomes, including maximum tolerated dose, change from baseline in Mobility course score, and pupillary response.

Allergan and Editas Medicine expect to complete the trial by March 2024.