Anton Hommer¹, Friedemann Kimmich²¹Sanatorium Hera, Vienna, Austria; ²eyecons, Pfinztal, GermanyPurpose: Efficacy, tolerability and safety of the novel preservative-free prostaglandin tafluprost 0.0015% were investigated for the treatment of patients with glaucoma or ocular hypertension in a clinical setting.Patients and methods: Data were collected in a non-interventional, prospective, multi-center, observational, open label study. 118 patients were treated with a prostaglandin analog (PGA) monotherapy (preserved formulations of latanoprost, travoprost or bimatoprost) prior to baseline. Intraocular pressure (IOP) readings were recorded for each eye at baseline (previous therapy), 4–6 weeks, and 12 weeks after changing medical treatment to preservative-free tafluprost once-daily. We analyzed the change in IOP over the study period for all patients as well as for a subgroup of patients with prior PGA monotherapy. Subjective symptoms and objective ocular signs were determined. Comfort was measured using a 4 step scale. All adverse events were recorded. Paired t-tests were conducted to compare IOP values at baseline to IOP values after treatment with tafluprost 0.0015%. Bowker’s test of symmetry was used for statistical evaluation of changes of clinical signs (hyperemia).Results: In total 118 patients were eligible for evaluation. In these patients with prior PGA monotherapy (n = 118) IOP decreased significantly from 16.2 ± 4.3 mm Hg (95% CI: 0.55) at treated baseline to 14.8 ± 3.2 mm Hg (95% CI: 0.43; P < 0.001) at final visit on tafluprost. In a subset of patients with prior latanoprost monotherapy (n = 68) mean IOP at baseline (±SD) was reduced from 16.2 ± 4.6 mm Hg (95% CI: 0.77) 14.8 ± 3.1 mm Hg at final visit (95% CI: 0.54, P < 0.001), in patients with prior travoprost monotherapy (n = 32) from 16.2 ± 4.3 mm Hg (95% CI: 1.05) to 14.9 ± 3.3 mm Hg (95% CI: 0.91; P < 0.05) and in patients with prior bimatoprost monotherapy (n = 18) from 16.4 ± 3.5 mm Hg (95% CI: 1.14) to 15.0 ± 3.3 mm Hg (95% CI: 1.14; P = 0.252). Both, objective clinical signs and subjective symptoms improved after changing medication to preservative-free tafluprost until final visit. The number of patients with moderate and severe hyperemia decreased from 51 (43.2%) at baseline to 2 (1.9%) at final visit.Conclusion: Preservative-free tafluprost 0.0015% was effective, well tolerated and safe. IOP was controlled effectively and ocular symptoms and clinical signs were improved after changing medication to a monotherapy with preservative-free tafluprost in patients previously treated with a preserved latanoprost, travoprost or bimatoprost monotherapy.Keywords: tafluprost, intraocular pressure, prostaglandin-analogs, preservatives, local tolerability hyperemi