Editas Medicine and Allergan have announced the first-ever dosing of an in vivo CRISPR-based therapy in a clinical trial. The recipient is an adult patient suffering from congenital blindness. This groundbreaking trial is designed to evaluate the safety and efficacy of EDIT-101 (also known as AGN-151587) in treating Leber congenital amaurosis type 10 (LCA10), a retinal degenerative disease caused by a mutation in the CEP290 gene.
Targeting the Root Cause of LCA10
LCA10, the most common form of Leber congenital amaurosis, results from the IVS26 mutation within the CEP290 gene. This mutation leads to a functional deficiency in the CEP290 protein, which is crucial for the proper function of retinal photoreceptors. The consequence is severe vision loss or blindness from early childhood.
EDIT-101 employs an adeno-associated virus vector, specifically AAV5, to deliver the CRISPR-Cas9 gene-editing machinery directly to the photoreceptor cells. The construct includes two guide RNAs that precisely target the IVS26 mutation, along with the Cas9 enzyme, which acts like molecular scissors to cut and remove the faulty genetic code. The goal is to restore normal CEP290 protein production and improve visual function.
Comparing Approaches: Gene Editing vs. Gene Augmentation
While EDIT-101 represents a gene-editing approach, another gene therapy, Luxturna (voretigene neparvovec-rzyl) from Spark Therapeutics (now Roche), addresses LCA caused by mutations in the RPE65 gene through gene augmentation. Luxturna introduces a correct copy of the RPE65 gene into the retinal cells. Both therapies utilize AAV vectors for delivery, but their mechanisms of action differ significantly. EDIT-101 aims to correct the mutation at its source, while Luxturna provides a functional replacement.
Clinical Significance and Future Implications
This clinical trial marks a pivotal moment in the field of gene therapy, demonstrating the potential of CRISPR-based therapies to treat inherited diseases directly within the human body. The outcome of this trial could pave the way for treating a wide range of genetic disorders previously considered untreatable. Further studies will be needed to assess the long-term safety and efficacy of EDIT-101 and to determine its potential impact on the lives of patients with LCA10.
