24-hr IOP With Travoprost/Timolol Compared With Latanoprost/Timolol in XFG

Inclusion Criteria: * Patient has XFG and is older than 29 years * The IOP without treatment is greater than 25 mm Hg and lower than 40 mm Hg at baseline (2 readings at 10:00) * Patient can be safely washed out without risk for significant deterioration * Distance best corrected Snelen visual acuity better than 0.1 * No contraindication to prostaglandins or β-blockers * No history of lack of response (\<10% reduction) to any medication * Patient can understand the instructions and comply to medications * Open normal appearing angles * No sign of ocular infection, except blepharitis, corneal abnormality that may affect IOP measurements etc Exclusion Criteria: * History of trauma, inflammation, surgery, past use of steroids (within 2 months), severe dry eyes and use of contact lenses * Patient is a female of childbearing potential or lactating mother