A single-blind , 12-week, parallel group clinical study is planned to evaluate the efficacy and safety of SPARC0912 and Reference0912. SPARC0912 is an experimental drug having similar active ingredient but containing a different preservative as that in Reference0912. Patients with open angle glaucoma or ocular hypertension will be enrolled and randomly assigned to receive either product. One drop will be instilled to the study eye nightly at 8:00 PM.