Changes in ocular signs and symptoms in patients switching from bimatoprost–timolol to tafluprost–timolol eye drops: an open-label phase IV study

Objectives: Bimatoprost–timolol (bimatoprost 0.03%–timolol 0.5% fixed-dose combination [FDC]) and tafluprost–timolol (tafluprost 0.0015%–timolol 0.5% FDC) eye drops are currently the only topical intraocular pressure (IOP)-reducing therapies available as preservative-free (PF) prostaglandin and timolol FDC. The aim of this study was to investigate changes to ocular signs and symptoms when patients with ocular hypertension (OH) or open-angle glaucoma (OAG) switched from PF or benzalkonium chloride (BAK)-preserved bimatoprost–timolol to PF tafluprost–timolol eye drops. Design: This was a 12-week, open-label, phase IV study. Setting: Sixteen centres in Finland, Germany, Italy and the UK. Participants: Patients with OH or OAG (IOP on medication ≤21 mm Hg), treated with PF or BAK-preserved bimatoprost–timolol for ≥4 weeks before screening, and presenting with conjunctival hyperaemia and ≥1 ocular symptom. Interventions: Patients were switched to PF tafluprost–timolol once daily in the treated eye(s). Primary and secondary outcome measures: The primary endpoints were change from screening to week 12 in conjunctival hyperaemia and worst ocular symptom. The secondary outcome measures were changes from screening in ocular signs (other than conjunctival hyperaemia) and symptoms at week 12. Results: Of 123 enrolled patients, 121 were included in the intention-to-treat dataset, of which all were Caucasian and 54.5% were female; 76 patients used BAK-preserved bimatoprost–timolol and 45 used PF drops. Conjunctival hyperaemia and severity of worst ocular symptom following switch to PF tafluprost–timolol significantly reduced from screening to week 12 in all patients (p<0.001). The percentage of patients with ocular signs and symptoms was significantly reduced at week 12 compared with screening (p<0.001). IOP was not affected by the change of treatment. Conclusions: Switching from BAK-preserved or PF bimatoprost–timolol to tafluprost–timolol reduced both signs and symptoms of ocular surface disease with no clinically relevant effect on IOP.