Fixed-combo brinzolamide 1%/brimonidine 0.2% lowers IOP in patients with OAG, OHT
The fixed-dose combination of brinzolamide 1% and brimonidine 0.2% (BBFC) is superior to vehicle in lowering intraocular pressure (IOP) over a 24-hour period following 4 weeks of 3-times-daily treatment in patients with open-angle glaucoma (OAG) or ocular hypertension (OHT), a study has shown.
“Treatment with BBFC administered [three times daily] demonstrated superior 24-hour IOP-lowering efficacy compared with vehicle over 4 weeks in subjects with OAG or OHT,” the researchers said. “[BBFC] reduced IOP during both the daytime and the nocturnal periods with no new safety signals identified.”
This prospective, multicentre, double-masked, parallel-group clinical trial was conducted at 16 academic and nonacademic sites in the US and included patients with OAG or OHT aged ≥18 years with mean baseline IOP measurements in at least one eye of ≥21 and <28 mm Hg.
The researchers collected duplicate mean pneumatonometer IOP measurements every 2 hours over a 24-hour period in controlled light conditions in overnight facilities. Daytime (8 am–8 pm) and nocturnal (10 pm–6 am) IOP measurements were collected in a sitting or supine position, respectively. Baseline 24-hour IOP was measured in untreated patients after a washout (up to 4 weeks) and eligibility phase.
A total of 125 participants were randomly assigned after baseline visit to receive either masked BBFC (n=62) or vehicle (n=61), one drop three times daily (8 am, 3 pm and 10 pm) for 4 weeks. IOP measurement was repeated in both groups under the same conditions at week 4. The primary outcome was mean change from baseline in 24-hour IOP at week 4.
Ninety-eight percent (n=123) of the participants completed the study, and none of those assigned to BBFC discontinued the study.
Eyes treated with BBFC vs vehicle had significantly reduced mean 24-hour IOP at week 4 (least squared mean difference, –2.5, 95 percent CI, –3.3 to –1.7; p<0.001). Reductions were observed both during the day (–3.4, –4.3 to –2.6; p<0.001) and the night (–1.2, –2.3 to 0.0; p=0.053). [Ophthalmology 2019;126:1095-1104]
Significant differences were observed in the mean change from baseline between BBFC- and vehicle-treated eyes at all daytime points and three of five nocturnal time points (10 pm, 12 am and 6 am; secondary endpoint).
Adverse events (AEs) were similar in terms of frequency between the two groups. The most commonly reported AEs in the BBFC arm were ocular hyperaemia, corneal abrasion and dysgeusia, which were consistent with those described in the drug label.
Previous studies have shown the efficacy of BBFC treatment in lowering IOP during daytime hours (8 am –5 pm at month 3), as well as its safety and tolerability in patients with OAG and OHT, but there has been a lack of data showing the effect of BBFC during the 24-hour period, particularly in the night-time hours. [J Ocul Pharmacol Ther 2013;29:290-297; JAMA Ophthalmol 2013;131:724-730; Eye (Lond) 2013;27:841-847]
“Previous studies have shown that peaks in IOP in [patients] with glaucoma or OHT frequently occur during the night-time period with the participant in the supine position,” the researcher said. [Invest Ophthalmol Vis Sci 2003;44:4439-4442; Invest Ophthalmol Vis Sci 2013;54:512-517; Ophthalmology 2010;117:2075-2079]