Abstract
PURPOSE: Studies comparing the two different formulations of bimatoprost, 0.03% and 0.01%, have shown similar efficacy, but a better adverse effect profile for bimatoprost 0.01% in patients with primary open-angle glaucoma (POAG) and ocular hypertension (OHT). This study assesses the efficacy and tolerability of switching from bimatoprost 0.01% to 0.03% in a patient population with broader spectrum of diagnoses in a real-world clinical setting. DESIGN: Single-centre retrospective observational switch study. METHODS: Selected patients were on initial topical therapy with bimatoprost 0.01% prior to switching to bimatoprost 0.03%. Intraocular pressure (IOP) was collected from their pre-switch visit, 6- and 12-week after switch. Paired two-sample t-test was performed to compare IOP at different time points versus baseline. Worsening of hyperemia and other adverse events after the switch were identified. Subgroup analysis was performed for POAG and OHT, secondary open-angle glaucoma (SOAG, including pseudoexfoliative and pigmentary glaucoma), normal tension glaucoma (NTG), and angle closure glaucoma (ACG). RESULTS: The study population consisted of 248 eyes (143 patients). There was a significant mean IOP reduction of 1.0 ± 3.7 mmHg (p < 0.001, n = 248) from baseline to week-6 and 1.6 ± 4.0 mmHg (p < 0.001, n = 142) from baseline to week-12 after switch. The IOP reduction was statistically significant in patients with POAG and OHT (6-week: 1.0 ± 3.8 mmHg, n = 76; 12-week: 1.5 ± 4.1 mmHg, n = 49), ACG (6-week: 1.5 ± 4.1 mmHg, n = 72; 12-week: 2.3 ± 4.5 mmHg, n = 46), and NTG (6-week: 0.83 ± 2.5 mmHg, n = 42; 12-week: 1.12 ± 2.1 mmHg, n = 25). Patients with SOAG did not show statistically significant reduction in IOP at 6- or 12-week after switch. Forty-two (29%) of 143 patients experienced adverse events, with the most common being hyperemia (16%). CONCLUSION: Significant reduction in IOP could be seen after switching from bimatoprost 0.01% to bimatoprost 0.03% in various types of glaucoma except SOAG. Intolerance after switch may be experienced, though not in the majority of cases.