Efficacy of the Brand-name Latanoprost and One of Its Generic Version in Primary Open Angle Glaucoma and Ocular Hypertension

Inclusion Criteria: 1. \>18 years old 2. Primary open angle glaucoma, glaucoma suspect or ocular hypertension 3. Bilateral 4. Without any treatment or treated with latanoprost or another prostaglandin analog 5. Intraocular pressure \>21mmHg (without treatment or after a washout period) Exclusion Criteria: 1. Intraocular pressure \>30mmHg 2. Secondary glaucoma (uveitic, neovascular, traumatic ) or congenital glaucoma 3. Pseudoexfoliation syndrome 4. Pigmentary dispersion syndrome or Pigmentary glaucoma 5. Severe glaucoma; Cup-to-disc ratio ≥9/10 OU Loss of central visual field (central 10°) 6. Use of other topical medication to lower intraocular pressure 7. Pregnancy and breast-feeding 8. Being allergic to latanoprost or benzalkonium chloride (BAK) 9. Current use of acetazolamide (Diamox) 10. Changes of systemic doses of beta-blockers during study 11. Recent use of topical corticosteroids (\<1 month) 12. Contact lens wearer 13. Closed angle at gonioscopy or past angle closure glaucoma 14. Filtration surgery (example. : trabeculectomy) 15. Selective Laser Trabeculoplasty (SLT) or Argon Laser Trabeculoplasty(ALT) 16. Recent Intraocular surgery (\<3 months) 17. Refractive surgery 18. Recent iridotomy or capsulotomy (\<3 months) 19. Past medical history of ocular trauma (example : angle recession) 20. Past or active uveitis 21. Herpetic keratitis 22. Monocular vision