Subretinal Photovoltaic Implant to Restore Vision in Geographic Atrophy Due to AMD

Geographic atrophy due to age-related macular degeneration (AMD) is the leading cause of irreversible blindness and affects more than 5 million persons worldwide. No therapies to restore vision in such persons currently exist. The photovoltaic retina implant microarray (PRIMA) system combines a subretinal photovoltaic implant and glasses that project near-infrared light to the implant in order to restore sight to areas of central retinal atrophy.

We conducted an open-label, multicenter, prospective, single-group, baseline-controlled clinical study in which the vision of participants with geographic atrophy and a visual acuity of at least 1.2 logMAR (logarithm of the minimum angle of resolution) was assessed with PRIMA glasses and without PRIMA glasses at 6 and 12 months. The primary end points were a clinically meaningful improvement in visual acuity (defined as ≥0.2 logMAR) from baseline to month 12 after implantation and the number and severity of serious adverse events related to the procedure or device through month 12.

A total of 38 participants received a PRIMA implant, of whom 32 were assessed at 12 months. Of the 6 participants who were not assessed, 3 had died, 1 had withdrawn, and 2 were unavailable for testing. Among the 32 participants who completed 12 months of follow-up, the PRIMA system led to a clinically meaningful improvement in visual acuity from baseline in 26 (81%; 95% confidence interval, 64 to 93; P<0.001). Using multiple imputation to account for the 6 participants with missing data, we estimated that 80% (95% CI, 66 to 94; P<0.001) of all participants would have had a clinically meaningful improvement at 12 months. A total of 26 serious adverse events occurred in 19 participants. Twenty-one of these events (81%) occurred within 2 months after surgery, of which 20 (95%) resolved within 2 months after onset. The mean natural peripheral visual acuity after implantation was equivalent to that at baseline.

In this study involving 38 participants with geographic atrophy due to AMD, the PRIMA system restored central vision and led to a significant improvement in visual acuity from baseline to month 12. (Funded by Science Corporation and the Moorfields National Institute for Health and Care Research Biomedical Research Centre; PRIMAvera ClinicalTrials.gov number, NCT04676854.).