Prospective randomized clinical trial on the effects of latanoprost, travoprost and bimatoprost on latanoprost non-responders

Purpose. - To determine whether a patient who is non-responder to latanoprost after one month of use should continue using latanoprost or switch to either bimatoprost or travoprost. Patients and methods. - Prospective randomized clinical trial. We recruited new patients who were felt to require intraocular pressure reduction. Patients who had <= 20% intraocular pressure reduction after one month of latanoprost treatment were randomly assigned to another month of treatment with latanoprost or a switch to bimatoprost or travoprost for an additional month. Results. - Overall, 83 non-responders to latanoprost after one month of treatment were included in the study. Before latanoprost treatment, the mean intraocular pressure was 23.7 +/- 4.7 mmHg. At randomization on latanoprost, mean intraocular pressure was 21.5 +/- 4.5 mmHg. One month after the switch of medication, the mean reduction in intraocular pressure was not significantly different between the groups (P = 0.148) and was -0.9 mmHg, -2.10 mmHg and 2.5 mmHg, for latanoprost, bimatoprost and travoprost respectively. One month after randomization, 32 (38.5%) of the patients had become responders, with IOP reduction > 20%. Of those patients, 9 (31%) were using latanoprost, 13 (41.9%) bimatoprost and 10 (43.5%) travoprost. The number of new responders was similar between the three groups (P = 0.584). Conclusion. - There is no added benefit of switching latanoprost to another topical prostaglandin for patients who are initially non-responders. Regression towards the mean and the Hawthorne effect are probably important factors explaining the additional IOP reduction obtained after randomization and explain the result of most switch studies. (C) 2019 Elsevier Masson SAS. All rights reserved.