OBJECTIVE: To compare the efficacy of latanoprost, bimatoprost and travoprost for controlling IOP using data published in the literature. METHODS: Randomized clinical trials were identified on Medline and Embase using the following key words: glaucoma, ocular hypertension, randomization, trial, latanoprost, bimatoprost and travoprost. The trials had to compare at least two prostaglandins head-to-head in monotherapy. Cross-over experimental designs were excluded. Sample size, IOP at inclusion and final visit, age, gender, race and period of follow-up were collected. Daily average IOP was estimated when measurements were available over the study period. Latanoprost was used as the reference treatment for comparisons. Multiple regression analyses estimated the effects of the different treatments on IOP after controlling for IOP at inclusion and duration of follow-up. All analyses were weighted using number of patients (inversely proportional to variance weights). RESULTS: 224 papers were identified, including 15 randomized clinical trials, which compared two prostaglandin monotherapies. Six studies were excluded: three cross-over designs, one with daily intake not in accordance with the SmPC, one combination study, and one without documented average IOP. The average age varied from 56.7 to 68.8 years and the IOP at inclusion from 22.3 to 26.5 mmHg. 378 patients were treated with bimatoprost, 385 with travoprost and 548 with latanoprost. After adjusting for baseline IOP and period of follow-up, both patients treated with travoprost and bimatoprost tended to have a lower IOP (-0.63 mmHg [-1.56;0.30] and -0.78 mmHg [-1.75;0.18], respectively) than those treated with latanoprost. After adjusting for IOP at baseline, follow-up period, age and gender the treatment effects were -0.72 [-2.02;0.57] and -0.69 [-2.04;0.65] for travoprost and bimatoprost, respectively. CONCLUSION: Based on the information available in the literature, travoprost and bimatoprost may have greater efficacy than latanoprost in controlling the IOP for patients with ocular hypertension or glaucoma.