24-Hour Efficacy and Ocular Surface Health with Preservative-Free Tafluprost Alone and in Conjunction with Preservative-Free Dorzolamide/Timolol Fixed Combination in Open-Angle Glaucoma Patients Insufficiently Controlled with Preserved Latanoprost Monotherapy

INTRODUCTION: The aim of the present study was to evaluate the 24-h efficacy, tolerability, and ocular surface health with preservative-free (PF) tafluprost and a PF triple drug regimen comprising tafluprost and dorzolamide/timolol fixed combination (DTFC) in open-angle glaucoma patients who were insufficiently controlled with preserved branded or generic latanoprost monotherapy and who exhibited signs or symptoms of ocular surface disease (OSD). METHODS: Prospective, observer-masked, crossover, comparison. Eligible consecutive open-angle glaucoma patients were randomized to either PF tafluprost or the triple PF regimen for 3 months. They were then crossed over to the opposite therapy for another 3 months. At the end of the latanoprost run-in period and after each PF treatment period, patients underwent habitual 24-h intraocular pressure (IOP) monitoring with Goldmann tonometry in the sitting position (at 10:00, 14:00, 18:00, and 22:00) and Perkins tonometry in the supine position (at 02:00 and 06:00). Tolerability and selected ocular surface parameters were evaluated at baseline and the end of each treatment period. RESULTS: Forty-three open-angle glaucoma patients completed the trial. Mean 24-h IOP on preserved latanoprost was 22.2 ± 3.9 mmHg. Compared with latanoprost monotherapy, PF tafluprost obtained a greater reduction in mean, peak, and fluctuation of 24-h IOP including the 02:00 and 06:00 time points (P < 0.05). With the exception of 24-h fluctuation, the triple PF regimen provided significantly lower IOP parameters than latanoprost or PF tafluprost (P < 0.001). Finally, PF tafluprost therapy displayed significantly improved tear film break-up times (6.7 vs 6.0 s), corneal staining (1.3 vs 2.2), and Schirmer I test results (9.1 vs 8.2 mm) compared with the preserved latanoprost baseline (all P < 0.01). The triple PF regimen demonstrated similar tear film break-up times (6.1 vs 6.0 s) and Schirmer I test results (8.2 vs 8.2 mm) to latanoprost, but revealed a significant improvement in the corneal stain test (1.7 vs 2.2; P < 0.001). CONCLUSIONS: In this trial PF tafluprost therapy provided statistically greater 24-h efficacy and improved tolerability compared with preserved latanoprost. The combination of PF tafluprost and PF dorzolamide/timolol fixed combination was statistically and clinically more efficacious than both monotherapies and demonstrated similar ocular surface characteristics to preserved latanoprost monotherapy. TRIAL REGISTRATION: ClinicalTrials.gov (NCT02802137). FUNDING: Santen.