Improved performance and safety from Argus II retinal prosthesis post‐approval study in France

Abstract

To evaluate the post-approval long-term outcomes of the Argus II Retinal Prosthesis, with a specific focus on its functional visual benefit in patients' daily activities. Methods: Eighteen patients with bare light perception due to end-stage retinitis pigmentosa were included in a French prospective, multicentre, single-arm study and followed for 2 years. Visual benefit in patients' daily activities was monitored through the use of the Functional Low-vision Observer Rated Assessment (FLORA), and the final score at 2 years was the primary effectiveness outcome. Standardized visual assessments were also performed. Device-or procedure-related adverse events were recorded. Results: Seventeen subjects completed the study. Positive impacts of the Argus II system on functional vision and well-being were demonstrated for over 70% of subjects on the FLORA. Among the daily activities/tasks tested, finding doorways was one of the most statistically significantly improved tasks (p < 0.001), along with estimating the size of an obstacle (p < 0.001), visually locating a place setting on a dining table (p < 0.001) and visually locating people in a non-crowded setting (p < 0.001). Visual function was improved on most standardized tests. Only two device-or procedure-related serious adverse events were observed (one vitreous haemorrhage and one endophthalmitis, both resolved with treatment). No explantation was required. Conclusion: This first report of a completed post-approval study of Argus II with a two-year follow-up demonstrates the safety and effectiveness of the Argus II System in a real-world cohort of patients and further highlights its real functional benefit in implanted patients' daily activities.

Functional Vision in the Real-World Environment With a Second-Generation (44-Channel) Suprachoroidal Retinal Prosthesis

“…Two further tasks in the “Daily Life” domain (Task 22, identify top step/bottom step, and Task 23, negotiate stairways independently) were also already “easy” with the device OFF and had no additional benefit with the device ON. This agrees with the Argus II studies, 18 , 19 where two of these three tasks were actually found to be easier with device OFF (travel within home independently, identify top step/bottom step) in the initial study. Notably, for the Alpha AMS data, the activity of daily living that was most positively affected by the implant was reported to be “walking in familiar areas.” 23 However, it is hard to make a direct comparison of navigation outcomes in familiar environments using different testing tools.…”

“…The combined quantitative and qualitative data suggests the suprachoroidal device provides real-world benefit. The positive impacts of the device in activities of daily living are similar to those reported in studies with the FLORA instrument in Argus II patients 18 , 19 and with the Modified Turano Independent Mobility Questionnaire in Alpha AMS patients. 23 Hence, our real-world assessment of the suprachoroidal retinal prosthesis with the FLORA tool supports our interim laboratory-based orientation and mobility results showing that device ON performs better than the device OFF in high-contrast indoor conditions (Kolic M. et al, IOVS, 2021, 62, ARVO E-Abstract).…”

“…2 ). In comparison, the Argus II longitudinal FLORA findings 19 found similar levels of improvement between the “Visual Orientation,” “Visual Mobility,” and “Daily Life” domains (67%, 80%, 58% improvement from baseline, respectively), and minimal improvement in the “Interaction with Others” domain (14%). The Alpha AMS device cannot be directly compared, as the tool to measure activities of daily living was different.…”

“…Nonetheless, the data clearly showed a benefit with the device ON, making common and simple tasks even easier to complete, and aligning with the Argus II findings for task 13. 19 The overall finding for the “Daily Life” domain suggests that the addition of extra visual information to other senses such as touch and proprioception made completing functional vision tasks in the real world easier.…”

“…If multiple modes were present, the higher mode was taken. For each task in Part 2 at endpoint, ease was compared between device ON and OFF using Wilcoxon's matched-pairs signed-rank test as per previous results with the Argus II device, 18 , 19 noting that because of sample size in a primary safety study, it was underpowered for this purpose. Not all tasks were completed by subjects at all time points because of subject and environmental factors.…”