Introduction: The efficacy of lowering intraocular pressure (IOP) and safety of switching to travoprost/timolol fixed combination ophthalmic solution (Duotrav(®), Alcon Laboratories, Inc., Fort Worth, TX, USA) in patients with primary open-angle glaucoma, normal tension glaucoma or ocular hypertension undergoing prostaglandin analog (PGA) monotherapy was investigated.
Methods: Patients treated with travoprost, latanoprost, tafluprost, or bimatoprost for ≥3 months and requiring additional medication were switched to Duotrav without washout. Baseline IOP was calculated from measurements at two visits during PGA monotherapy. IOP reductions at 4, 8, and 12 weeks after switching to Duotrav and adverse events were assessed.
Results: Of 162 patients enrolled, 157 patients (96.9%) with ≥4 weeks of follow-up after switching to Duotrav were analyzed. The mean IOP decreased significantly (baseline = 16.3 ± 3.1 mmHg; 4 weeks = 14.6 ± 3.1 mmHg, 8 weeks = 14.7 ± 3.3 mmHg, 12 weeks = 14.6 ± 3.2 mmHg; all P < 0.0001). When study eyes were divided into three groups according to baseline IOP (≥19 mmHg: 33 eyes, 21.0%; ≥15 to <19 mmHg: 78 eyes, 49.7%; <15 mmHg: 46 eyes, 29.3%), all groups showed significant IOP reductions (P = 0.0324 ~ P < 0.0001) after switching to Duotrav. Twenty-seven of 166 patients (16.3%) in the safety analysis experienced adverse events and 26/166 patients (15.7%) experienced adverse events, for which a relationship to Duotrav could not be ruled out. Adverse events in five patients led to treatment discontinuation (eye pruritus; eye irritation; increased blood pressure and rash; increased blurred vision; deepening of the eyelid sulcus and blepharoptosis). Twelve weeks after treatment switching, eyelash changes, blepharal pigmentation and deepening of the eyelid sulcus occurred in 42 (26.8%), 29 (18.5%), and 13 (8.3%) cases, respectively, among 157 patients with follow-up. There was no significant worsening from baseline for superficial punctate keratopathy (SPK) or conjunctival hyperemia after switching (SPK score: baseline = 0.58 ± 1.31; 12 weeks = 0.92 ± 1.76, P = 0.1819; conjunctival hyperemia score: baseline = 0.41 ± 0.64; 12 weeks = 0.49 ± 0.63, P = 0.3774).
Conclusion: Our findings confirm that switching to Duotrav(®) in PGA monotherapy patients shows IOP-lowering effect with minimal safety concerns.
Funding: Japan Association of Health Service and Alcon Japan. Ltd.
Trial registration: UMIN Clinical Trials Registry identifier, UMIN000007028.
Keywords: Adverse event; Intraocular pressure; Side effect; Switching therapy; Travoprost/timolol fixed combination.