The study, published in Ophthalmology yesterday, examined 30 patients implanted with the Argus II, designed to restore partial vision by stimulating viable retinal cells in patients with severe to profound retinitis pigmentosa, the Sylmar, Calif.-based company said.
At 3 years, 29 patients remain implanted with the system and 89% of subjects performed better with the system in visual function tasks, the study reports.
Eighty percent of patients benefited from the system according to a functional low-vision observer rated assessment of patients with the device, the study reports, and no subjects were affected negatively.
“We are thrilled to see positive results from this study, supporting the safety and benefit of the Argus II. The results from the trial demonstrated long-term reliability of the device, long-term benefit to the users, and an acceptable safety profile. Together, these results show that the Argus II provides a substantial visual improvement over blindness. Having this device backed by significant, long-term clinical data is cause for great hope among those individuals suffering from RP and should further our efforts across the globe in securing regulatory and reimbursement approvals,” CEO Dr. Robert Greenberg said in a press release.
At 1 year, 66% of subjects had no device or surgical serious adverse events, the study reports. At 3 years, 11 subjects experienced serious adverse events that were successfully treated, with 1 patient having the device removed.
“Of course, this is only the beginning. We are constantly making improvements in our technology and are striving to greatly improve image quality and resolution for the Argus II. With our ongoing development efforts toward the Orion I cortical visual prosthesis, we hope to offer a solution for people living with blindness from nearly all causes,” Greenberg said.
The device functions by converting images from a small glasses-mounted video camera to electrical pulses, which are sent wirelessly to an array of electrodes implanted on the surface of the retina, Second Sight said. Patients learn to interpret the new visual patterns and regain some visual function, the company said.
“The data from this study is quite remarkable for these patients who, previously, had little to no light perception, living in a world that we could consider complete darkness. The fact that these individuals have increased independence, being able to navigate through their home, walk through doorways and cross streets, is truly life changing,” director of retina research at the Wills Eye Hospital Dr. Allen Ho said in prepared remarks.
The Argus II is the first artificial retina to gain a CE Mark in the European Union and is the only retinal prosthesis so far to have FDA approval, the company said.
Last month, Second Sight said it had performed the 1st successful implantation of a mechanical model of its next-generation Orion I device in a pre-clinical study. The company calls Orion 1 a “visual cortical prosthesis” designed to bypass the eye and the optic nerve using an electrode implanted into the visual cortex of the brain.