PURPOSE: To evaluate the intraocular pressure (IOP)-lowering effect and safety of up to 2 bimatoprost implant administrations versus selective laser trabeculoplasty (SLT). DESIGN: Phase 3 (Stage 2), randomized, 24-month, multicenter, patient- and efficacy evaluator-masked, paired-eye clinical trial (NCT02507687). PARTICIPANTS: Patients (n = 183) with open-angle glaucoma or ocular hypertension inadequately managed with topical IOP-lowering medication for reasons other than efficacy. INTERVENTION: Patients received a single 360° SLT procedure in 1 eye and 10-µg bimatoprost implant administration in the contralateral eye. Initially, implant-treated eyes received a second implant at week 16 if safety criteria were met. After a protocol amendment, implant-treated eyes were retreated with flexible scheduling if IOP was >
17 mm Hg and safety criteria were met. MAIN OUTCOME MEASURES: The primary efficacy variable was IOP change from baseline, with primary timepoints at weeks 4, 12, and 24. Safety measures included treatment-emergent adverse events (TEAEs) and ocular safety measures. RESULTS: Mean (±SE) baseline IOP (mm Hg) was 25.2 ± 0.22 and 25.1 ± 0.22 in implant- and SLT-treated eyes, respectively. Least-squares mean (±SE) IOP reduction from baseline (mm Hg) for eyes treated with up to 2 implants versus SLT was 6.8 ± 0.28 versus 6.2 ± 0.28 at week 4, 6.9 ± 0.30 versus 6.4 ± 0.30 at week 12, and 6.9 ± 0.27 versus 6.5 ± 0.28 at week 24. The probability of not having required nonstudy (rescue) IOP-lowering treatment at days 360 and 720, respectively, was 67.5% and 50.2% for implant-treated eyes versus 68.7% and 60.6% for SLT-treated eyes. The most common ocular TEAE in both implant- and SLT-treated eyes was increased IOP attributed to wearing off of efficacy. Mean (±SE) percentage change in corneal endothelial cell density from baseline at month 24 was -6.2 ± 1.13% in implant-treated eyes (-7.9 ± 2.04% with fixed readministration
-5.2 ± 1.35% with flexible readministration) versus -3.1 ± 0.43% in SLT-treated eyes. CONCLUSIONS: The bimatoprost implant demonstrated statistical and clinical noninferiority to SLT in IOP reduction from baseline at weeks 4, 12, and 24. In subgroup analysis, patients with flexible implant readministration met the same criteria. Both the implant and SLT demonstrated sustained (2-year) IOP lowering in many eyes. A flexible administration schedule improved the safety profile of the implant over the fixed administration schedule.