Second Sight’s Argus II Shows Strong Performance at the Five-Year Mark
With news that the global market for retinal implants is expected to skyrocket to $1.1 billion by 2022, investigators of Second Sight Medical Products’ Argus II retinal implant chose a good time to report that five-year results are in line with the previously reported three-year outcomes.
The results were reported at the 39th Annual Macula Society Meeting last week in Miami Beach. “After five years the benefits of the patients who received Argus II are maintained and the safety profile is maintained, and with the commercial rollout it seems that few complications have been reported,” James Tahara Handa, MD, of Johns Hopkins Wilmer Eye Institute, said at the meeting on behalf of the Argus II Study Group.
A day after Dr. Handa reported the results, Second Sight founder Alfred E. Mann died at age 90. In a 70-year career, Mann founded 16 other companies besides Second Sight. Among the medical breakthroughs those companies pioneered are infusion and insulin pumps, pacemakers, cochlear implants, spinal cord stimulators, and inhalable insulin. Three companies became public and 10 were acquired at an overall total of almost $8 billion.
Second Sight chairman Robert Greenberg, MD, PhD, released the following statement: “We are all deeply saddened by the loss of our founder, mentor and friend, Al Mann, a pioneering leader whose contributions and vision profoundly impacted the lives of so many and whose legacy will impact many more. Everyone he came in contact with was enriched and inspired by him. Personally, I am eternally grateful for Al’s generous guidance and support these last 16 years. At Second Sight, we all feel deeply honored to have worked alongside of and known such a remarkable person. The world is a little darker without his presence, but his spirit will live on in every blind person who is brought back into the light by our products.”
At the Macula Society meeting, Dr. Handa reported on the study that involved 30 subjects from the clinical trial who received the implants at 10 centers. Before the implant all were blind, defined as bare light perception or worse, due to retinitis pigmentosa or other disorders.
On average, the study participants had the implant for seven years, with the longest at 8.4 years. The Argus II remained implanted and functioning in 24 subjects. In all, the subjects totaled more than 200 years of experience with Argus II, the largest and longest running study of a visual prosthesis to date, Dr. Handa said.
“The five-year data looks basically the same as the three-year data in the two primary components: the adverse events rate did not change; and the performance of when people used the Argus II turned on was maintained,” Dr. Handa said. “After three years, patients are likely to continue to perform well at five years.”
The study reported a total of 24 serious adverse events at five years, all of which were “addressed with standard ophthalmic techniques,” and no eyes were lost. Most complications related to the Argus II occurred in the first year after implantation, Dr. Handa said.
The study used a number of tests to evaluate visual function in patients with the system switched on compared with off. The tests and the percentage of subjects who noted improvement with the system on are:
- Square Localization (ability to locate and touch a high-contrast target), 81%.
- Direction of Motion (ability to determine the direction of a high-contrast target), 50%.
- Grating Visual Acuity (ability to distinguish the orientation of black and white bars of different widths), 38%.
And as a group, performance on the Door and Line Orientation and Mobility tasks was significantly better, Dr. Handa said.
Since the commercial rollout of Argus II in Europe in 2011, the rates of adverse events have actually improved over the clinical trial, Dr. Handa said. “There are 111 patients who have had the implant placed worldwide after it was approved, and the adverse event rate was actually lower for each category of possible complication than it was during the first year of the clinical trial,” he said.
He called the decline in adverse event rates “pretty remarkable,” adding, “Anytime you have a foreign object anywhere in the body, there’s always risk of erosion of the tissue or infection, and so far that just doesn’t seem to be occurring through five years.”
“The five-year Argus II clinical data reported by Dr. Handa are quite positive,” said Second Sight board member Bill Link, PhD, who is also managing director of Versant Ventures, which holds a large equity position in Second Sight. “As a leader in this sector, Second Sight remains committed to build upon these accomplishments and drive continuous innovation in helping blind people see.”
Besides offering the system in the US, Second Sight markets the Argus II in Austria, Canada, Germany, France, Netherlands, Italy, Saudi Arabia, Switzerland, Turkey, Spain, and the UK.
In an earlier report, market research firm Grand View Research estimated the global market for retinal prostheses would soar from around $14 million last year to more than $1.1 billion by 2022.
Other players in the space with commercially available retinal implants are VisionCare Ophthalmic Technologies in Saratoga, CA, with its FDA- and CE-approved Implantable Miniature Telescope (IMT), and Retina Implant AG, whose Alpha IMS implant is available only in Germany. These devices are mostly indicated to restore vision in end-stage age-related macular degeneration (AMD). Bionic Vision Australia (BVA) and Boston Retinal Implant Project’s (BRIP’s) Bionic Eye Technologies Inc. and Visus Technology Inc. are also developing retinal prostheses.
Co-authors in the Argus II Study Group are Prof. Lyndon Da Cruz, Moorfields Eye Hospital, London; Prof. Paolo Stanga, Manchester Royal Eye Hospital, UK; Lisa Olmos de Koo, MD, University of Southern California; Alan Ho, MD, Wills Eye Hospital, Philadelphia; David Birch, PhD, Retina Foundation of the Southwest, Dallas; Jacque Duncan, MD, University of California, San Francisco; Pierre-Olivier Barale, MD, Center Hospitalier National d’Ophtalmologie des Quinze-Vingts, Paris; Prof. Dr. Gabriele Thumann, University Hospital of Geneva; and Robert Greenberg, MD, PhD, chairman of Second Sight Medical Products.