“Landmark” genetic blindness CRISPR trial outcomes released

New results from a Phase I/II clinical trial of a CRISPR/Cas9 gene editing therapy show that around 79 percent of patients with a rare form of inherited blindness experienced “measurable improvement”.

The BRILLIANCE trial included 14 participants (12 adults and two children) who received an injection of EDIT-101 in one eye. These individuals had a form of Leber Congenital Amaurosis (LCA) caused by mutations in the centrosomal protein 290 (CEP290) gene.

“This trial represents a landmark [for the treatment of] genetic blindness, by offering an important alternative treatment, when traditional forms of gene therapy, such as gene augmentation, are not an option,” explained Dr Tomas Aleman, the Irene Heinz-Given and John LaPorte Research Professor in Ophthalmology at Penn Medicine with the Scheie Eye Institute and a paediatric ophthalmologist at Scheie Eye Institute at the Children’s Hospital of Philadelphia (CHOP) who served as a site principal investigator and study co-author.

Results showed:

• Eleven participants experienced improvements in at least one of four measures
• Six participants demonstrated improvement in two or more measures
• Four participants had clinically meaningful improvement in best-corrected visual acuity (BCVA)
• Six participants experienced meaningful improvements in cone-mediated vision, with five attaining improvements in at least one of the three other outcomes.

More about the CRISPR-based gene editing therapy trial

In the study, two adults received low-dose therapy, five received mid-dose, and a further five participants were given a high-dose treatment. Alongside this, two children received a mid-dose treatment of EDIT-101.

To assess the safety of the CRISPR-based gene editing medicine, participants were monitored every three months for twelve months. Follow up was done less often for a total of two additional years, the researchers confirmed.

Positively, the paper, published The New England Journal of Medicine, reported no serious treatment or procedure-related adverse events or dose-limiting toxicities.

What could the future bring?

“The results from the BRILLIANCE trial provide proof of concept and important learnings for the development of new and innovative medicines for inherited retinal diseases. We’ve demonstrated that we can safely deliver a CRISPR-based gene editing therapeutic to the retina and have clinically meaningful outcomes,” shared Dr Baisong Mei, PhD, Chief Medical Officer of Editas Medicine, the company which developed the medicine.

Hopefully, future studies will examine “ideal dosing, whether a treatment effect is more pronounced in certain age groups such as younger patients, and include refined endpoints to measure the effects of improved cone function on activities of daily living”, according to the researchers.

First CRISPR-based gene-editing therapy authorised