Heidi Ledford in Nature:
A person with a genetic condition that causes blindness has become the first to receive a CRISPR–Cas9 gene therapy administered directly into their body. The treatment is part of a landmark clinical trial to test the ability of CRISPR–Cas9 gene-editing techniques to remove mutations that cause a rare condition called Leber’s congenital amaurosis 10 (LCA10). No treatment is currently available for the disease, which is a leading cause of blindness in childhood. For the latest trial, the components of the gene-editing system – encoded in the genome of a virus — are injected directly into the eye, near photoreceptor cells. By contrast, previous CRISPR–Cas9 clinical trials have used the technique to edit the genomes of cells that have been removed from the body. The material is then infused back into the patient. “It’s an exciting time,” says Mark Pennesi, a specialist in inherited retinal diseases at Oregon Health & Science University in Portland. Pennesi is collaborating with the pharmaceutical companies Editas Medicine of Cambridge, Massachusetts, and Allergan of Dublin to conduct the trial, which has been named BRILLIANCE.
…For now, the use of CRISPR–Cas9 in the body is a significant jump from treating cells in a dish, says Fyodor Urnov, who studies genome editing at the University of California, Berkeley. “It is akin to space flight versus a regular plane trip,” he says. “The technical challenges, and inherent safety concerns, are much greater.”