Randomized crossover study of latanoprost and travoprost in eyes with open-angle glaucoma.

Introduction: To compare the intraocular pressure (IOP)-lowering effects of 0.005% latanoprost to that of 0.004% travoprost in eyes with open-angle glaucoma (OAG).

Methods: Forty-two patients with OAG who received either latanoprost or travoprost every evening for 12 weeks, and then switched to the other medication for another 12 weeks. The IOP measurements were made with a Goldmann applanation tonometer (GAT) at the baseline, and at 1, 3, 4, and 6 months after the treatment. The IOP at the untreated baseline and at the end of each treatment period was measured at 10:00, 12:00, and 16:00 hours. The central corneal thickness (CCT) was measured at each visit using an ultrasonic pachymeter.

Results: The mean baseline IOP was 13.9 ± 2.5 mmHg, and the CCT was 536.7 ± 30.5 μm. Latanoprost reduced the IOP by 2.5 ± 1.7 mmHg and travoprost by 2.6 ± 1.5 mmHg from the baseline (p = 0.6807). The CCT decreased significantly to 531.9 ± 30.3 at 3 months (p = 0.0160) and to 529.4 ± 30.5 μm at 6 months (p = 0.0002) after the therapy. The decrease was significantly greater in eyes after travoprost (p = 0.0049).

Conclusions: Travoprost has similar effect as latanoprost in reducing the IOP in glaucoma patients with relatively low IOPs. The use of prostaglandin analogs can decrease the CCT, and this change should be considered when the IOPs obtained by GAT are analyzed.