Low-dose brimonidine for relief of ocular redness: integrated analysis of four clinical trials.

Background The aim of this study was to provide an integrated analysis of safety and efficacy data for brimonidine tartrate ophthalmic solution 0.025 per cent (low-dose; Bausch & Lomb Incorporated), a topical vasoconstrictor for relief of ocular redness. Methods Integrated efficacy data from two randomised, double-masked, vehicle-controlled studies in subjects with ocular redness as well as safety data from the two efficacy studies, a vehicle-controlled safety study, and a pharmacokinetic study were analysed. Efficacy outcomes analysed included investigator-assessed ocular redness (scale, 0-4) before treatment instillation and at five to 240 minutes post-instillation on Day 1, at five minutes post-instillation on Days 15 and 29, and one week after treatment discontinuation (Day 36), and redness self-assessed by subjects recorded daily in diaries. Safety assessments included adverse events, ophthalmic examinations, and rebound redness upon treatment discontinuation. Drop comfort (scale, 0-10) was a tolerability measure. Results The efficacy population included 117 subjects (brimonidine, n = 78; vehicle, n = 39). The safety population included 635 subjects (brimonidine, n = 426; vehicle, n = 209). Investigator-assessed ocular redness was significantly lower with brimonidine versus vehicle at all post-instillation time points on Day 1 (mean change from pre-instillation of -1.4 units for brimonidine and -0.2 units for vehicle; p < 0.0001). Subject-assessed ocular redness was also significantly lower with brimonidine versus vehicle (mean treatment difference in average daily ratings of -0.9; p < 0.0001). There was no evidence of tachyphylaxis through Day 29 and rebound redness was rare. Incidence of ocular adverse events was low, the most common being reduced visual acuity (brimonidine, 4.0 per cent; vehicle, 4.3 per cent) and conjunctival hyperaemia (2.6 and 2.9 per cent, respectively). Both brimonidine and vehicle were rated as very comfortable (mean post-instillation scores, 0.4-0.5). Conclusion In this integrated analysis, low-dose brimonidine significantly reduced ocular redness with no tachyphylaxis, and minimal rebound redness, and was generally safe and well tolerated.