Assessing PRIMA’s Efficacy and Safety at 36 Months

Long-term results from the PRIMAvera study show approximately 30 letters of mean visual acuity improvement at 36 months, with most serious adverse events occurring early after surgery.

By: Ehsan Rahimy, MD

Retinal Physician October 14, 2026

Clinical Scorecard: Assessing PRIMA’s Efficacy and Safety at 36 Months

At a Glance

Category	Detail
Condition	Advanced end-stage geographic atrophy; mean baseline visual acuity in PRIMAvera was equivalent to 20/460.
Key Mechanisms	The subretinal photovoltaic chip converts near-infrared light from augmented-reality glasses into electrical current, stimulating retinal bipolar and ganglion cells and using the retina’s native signaling structure.
Target Population	PRIMAvera enrolled 38 patients with advanced end-stage geographic atrophy at more than 17 clinical sites in Europe; mean baseline visual acuity was equivalent to 20/460.
Care Setting	The study was conducted at more than 17 clinical sites in Europe. Implantation used a subretinal approach with standard pars plana vitrectomy.

Key Highlights

At 36 months, mean visual acuity improvement was approximately 30 ETDRS letters.
The study had previously reported a mean gain of 25 ETDRS letters at 12 months.
The study reported 29 serious adverse events; 83% occurred within the first 6 months after surgery.
Reported serious adverse events were managed and did not compromise patients’ natural vision with the device off.
Nearly two-thirds of patients who experienced a serious adverse event achieved at least 15 ETDRS letters of visual gain.

Guideline-Based Recommendations

Diagnosis

Management

Monitoring & Follow-up

Risks

Patient & Prescribing Data

PRIMAvera enrolled 38 patients with advanced end-stage geographic atrophy at more than 17 European clinical sites; mean baseline visual acuity was equivalent to 20/460.

Mean visual acuity gain was approximately 30 ETDRS letters at 36 months. Among patients who experienced a serious adverse event, nearly two-thirds achieved at least 15 letters of visual gain.