Background/aims This study evaluated nepafenac ophthalmic suspension 0.1% for prevention of macular oedema (MO) when used 90 days following cataract surgery in patients with diabetic retinopathy (DR).

Methods Randomised, double-masked, vehicle-controlled, parallel group study conducted at 32 centres across the world. Participants were patients with diabetes with non-proliferative diabetic retinopathy scheduled for cataract surgery with (posterior chamber) intraocular lens implantation. Patients were randomised to nepafenac ophthalmic suspension 0.1% or vehicle three times daily, beginning on the day before surgery and continuing through the last study visit (day 90 or early exit). All patients were instilled one drop of tobramycin 0.3% and dexamethasone 0.1% four times daily for 2 weeks after surgery. Primary efficacy end point was the percentage of patients who developed MO (defined as ≥30% increase in central subfield macular thickness from baseline) within 90 days following surgery. The secondary end point was mean change in best-corrected visual acuity (BCVA) from baseline to day 90.

Results A total of 175 patients were randomised, with 87 and 88 patients in the nepafenac and vehicle groups, respectively. A significantly greater percentage of eyes in the vehicle group (17.5%; 95% CI 9.9% to 27.6%) developed MO within 90 days following surgery compared with the nepafenac group (5.0%; 95% CI 1.4% to 12.3%, p=0.01). Mean change in BCVA from baseline to day 90 following surgery was greater in the nepafenac group (17.7±14.6 letters) relative to the vehicle group (14.3±13.9 letters), though the difference was not statistically significant (p=0.14). No new safety issues or trends were identified.

Conclusions A 90-day nepafenac treatment regimen prevented MO after cataract surgery in patients with DR and demonstrated no safety issues within this study group.

Trial registration number NTC00782717 and NCT00939276.