The purpose of this trial is to evaluate the safety and tolerability of INS115644 Ophthalmic Solution in subjects with bilateral ocular hypertension or early primary open angle glaucoma and to investigate the intraocular pressure lowering effects of INS115644 Ophthalmic Solution.

Inclusion Criteria:

• Have a diagnosis of bilateral ocular hypertension or early primary open angle glaucoma
• Have best corrected visual acuity in both eyes of at least +0.5 or better
• Have normal endothelial cell counts and morphology

Exclusion Criteria:

• Are diagnosed with closed angle glaucoma, exfoliation syndrome or exfoliation glaucoma, and pigment dispersion or secondary glaucoma
• Have a history of any type of intraocular surgery, except for cataract surgery
• Have had cataract surgery within three months