Background:The Tafluprost/Timolol Fixed Combination (TTFC) has demonstrated efficacy and safety in reducing Intraocular Pressure (IOP). However, direct comparisons of switching from tafluprost to TTFC are limited.Objective:To investigate the efficacy and safety of switching from tafluprost to TTFC in patients with Primary Open-Angle Glaucoma (POAG).Methods:Thirty-four eyes (34 patients) with POAG that did not achieve adequate IOP reduction on tafluprost were switched to TTFC with no washout period. IOP, systolic/diastolic blood pressure and pulse rate were measured 1 and 3 months later and compared with baseline values. All participants were asked about specific adverse reactions after 1 and 3 months of treatment. Patients also completed a questionnaire about preference and adherence after 1 month of treatment.Results:Mean IOP after 1 and 3 months was significantly lower than at baseline (14.2 ± 2.1 mmHg and 14.1 ± 2.3 mmHg, respectively, vs 16.0 ± 2.0 mmHg, P < 0.0001). Systolic/diastolic blood pressure and pulse rate were not significantly different from baseline after 1 and 3 months. The questionnaire indicated that the frequency of missing a dose was not different before (27.3%) or after (18.2%) switching to TTFC (P = 0.2371). There were five reports of adverse reactions (14.7%), including a corneal epithelium disorder, ocular irritation, skin irritation at the wrist, and chest pain. Two patients (5.9%) withdrew because of adverse reactions.Conclusion:Switching from tafluprost to TTFC achieved IOP control safely and was well accepted by patients.