['normal tension glaucoma']
['php-201 0.25% ophthalmic solution', 'php-201 0.5% ophthalmic solution', 'placebo ophthalmic solution']

        Inclusion Criteria:

          -  19 years and older, female and male

          -  IOP ≤21 mmHg

          -  Subject showing open angle finding, glaucomatous optic nerve damage and visual field
             defects

          -  BCVA ≥+0.2

        Exclusion Criteria:

          -  Subject with the disease and surgery history that are not eligible to participate
             (acute closed angle glaucoma, narrow angle glaucoma, advanced glaucomatous loss,
             ocular trauma, eye surgery or laser surgery, unstable angina, myocardial infarction,
             uncontrolled hypertension and diabetes, etc)

          -  Subject who can't discontinue contact lenses

          -  Subject who can't discontinue topical/systemic IOP lowering medication
      