A meta-analysis of randomized clinical trials comparing the efficacy and safety of latanoprost, travoprost, and bimatoprost in reducing the intraocular pressure

Purpose: To compare the intraocular pressure (IOP) reduction induced by latanoprost, travoprost, and bimatoprost. Comparison of drugs tolerability and side effects was also one aim of the study. Methods: Randomized clinical trials (RCTs) comparing the IOP reducing effect of latanoprost, travoprost, and bimatoprost, were electronically searched and collected. Methodological quality of the RCTs was reviewed by 2 independent evaluators. Data about drugs efficacy, tolerability and side effects were abstracted and statistically combined. Effect size calculation and Mantel–Haenszel–Peto method were used to obtain pooled estimates. Heterogeneity among studies’ results was also tested. Results: Eight RCTs were eligible and provided data from 1,165 patients, to be statistically combined. Out of the 8 RCTs, only 3 reported a statistically significant difference ammong prostaglandin analogues, favouring bimatoprost. The combination of the 8 studies’s results indicated that bimatoprost was the most effective prostaglandin analogue with a further 0.91 mm Hg (0.6–1.6) IOP reduction as compared with latanoprost. The heterogeneity among RCTs’ results was not statistically significant. Bimatoprost was associated with a significantly increased occurrence of ocular side effects (summary OR 2.79, 95% C.I. 2.11 to 3.68), while when only severe side effects were considered, there was no significant difference among prostaglandin analogues (summary OR 1.48, 95% C.I. 0.65 to 3.37). Conclusion: Bimatoprost was found to be the most effective prostagladin analogue. The difference between bimatoprost and other prostaglandin analogues was less than 1 mmHg. The benefit of this effect must be evaluated together with the rate of ocular discomforts.