Allergan and Editas Medicine have made history after scientists used a CRISPR treatment developed by the partners to edit cells inside the human body.
Until now, researchers have used CRISPR in human trials, but removed patients’ cells and edited them outside the body before re-injecting them – a process known as ex vivo treatment.
Allergan and Editas’ gene therapy – AGN151587 or EDIT-101 – is designed to treat a rare, inherited form of blindness known as Leber congenital amaurosis 10 (LCA10).
The condition often first occurs in infancy, and those with the condition have specific mutations in the genes responsible for the development of the retina, the part of the eye that detects light.
The historical CRISPR moment occurred in the phase 1/2 BRILLIANCE study, after the first LCA10 patient was dosed with the CRISPR genome editing medicine inside the body – or in vivo treatment.
Allergan and Editas plan to treat a further 18 LCA10 patients with EDIT-101, to evaluate the treatment’s safety, tolerability and efficacy.
Although there is a gene therapy available for Leber’s – Spark’s Luxturna – it doesn’t work for the specific gene mutation which causes LCA10.
In comparison to gene therapies, which insert a working copy of the gene which is missing in a rare disorder, CRISPR therapies are designed to modify the gene itself, instead of supplying a working copy.
CRISPR technology does this by breaking a specific place within DNA which triggers a self-repair mechanism.
However, instead of repairing the original sequence, CRISPR serves as a new template that can be used to modify the sequence and correct a faulty gene.
Although Allergan and Editas have claimed the first in vivo instance of CRISPR treatment, a number of pharma companies and biotechs are carrying out research in the area.
That includes Vertex and CRISPR Therapeutics – the partners recently revealed initial positive data from the first to patients treated with their investigational CRISPR/Cas9 therapy CTX001 for the treatment of severe haemoglobinopathies.
AstraZeneca is also making a play in the CRISPR field, with a collaboration on a CRISPR-focused research programme with the Wellcome Trust Sanger Institute, the Innovative Genomics Initiative, Thermo Fisher Scientific and the Broad Institute.