Nanoscope Therapeutics announced four blind retinitis pigmentosa (RP) patients with ABCA4 variants who received a single intravitreal gene therapy injection showed improvement in vision, shape discrimination and mobility.  

Optogenetics offers a therapeutic opportunity to restore vision by photosensitising remaining retinal neurons, said study authors, writing in Molecular Therapy. “However, current opsins are kinetically slow, partially activated in ambient light, unresponsive to different light colours and target low-resolution retinal cell circuits,” they said. Nanoscope’s engineered ‘mutation-agnostic’ synthopsin, MCO-010, was packaged into an AAV2 gene therapy vector that targets human retinal bipolar cells. Following injection, researchers used non-invasive imaging to confirm retinal gene expression via a fluorescent reporter protein. Patients’ improved vision was maintained through to 52 weeks with no significant safety issues reported.  

The MCO-010 treatment pathway

This is the first gene monotherapy to restore vision in blind patients in a mutation-independent manner utilising an optogenetics technology platform, representing a pivotal milestone in the treatment of inherited retinal degenerations, said Professor Vinit Mahajan, study co-author and vice chair for research, Stanford University’s Department of Ophthalmology. "The ability to restore vision with a single intravitreal injection marks a significant step toward developing a universal treatment for retinal degenerative diseases,” he said.