Study of ST266 Given by Intranasal Delivery in Glaucoma Suspect Subjects

Inclusion Criteria: 1. Signed Informed Consent Form and HIPAA (Health Insurance Portability and Accountability Act) document. 2. Male or Female, Ages 20-75 years. 3. Must be clinically followed as a glaucoma suspect without evidence of glaucomatous damage. 4. Must have one of the following: 1) IOP ≤ 28 mmHg and at least one (1) IOP measurement \> 21 mmHg, or 2) physiologic cupping of the optic nerve, or 3) a family history of glaucoma. 5. Two (2) normal visual fields (VF) both Swedish Interactive Threshold Algorithm - Short-wavelength Automated Perimetry (SITA-SWAP) and 24-2 VF prior to subject enrollment at the Baseline Visit. 6. Two (2) normal Ocular Coherence Tomography (OCT) (of macula and nerve fiber layer) prior to subject enrollment at the Baseline Visit. 7. Gonioscopy open to at least scleral spur with normal iris configuration. 8. Normal baseline neuro-cognitive testing. 9. Normal baseline Magnetic Resonance Imaging (MRI), including expected age-related changes, performed with and without contrast. 10. Cohort Three group only: Baseline Lumbar Puncture within normal limits. Exclusion Criteria: 1. Females of Child Bearing Potential (FOCBP) who are pregnant or lactating or who will not abstain from sexual activity for 14 days prior to Visit 1, and willing to remain so through 30 days following completion of the subject's first menstrual cycle following the End of Treatment (EOT) Visit. Alternatively, a WOCBP who will not remain abstinent must have been using one of the following acceptable methods of birth control for the times specified: * IUD in place for at least three (3) months prior to Visit 1 until completion of the subject's first menstrual cycle following the EOT Visit. * Barrier method (condom or diaphragm) with spermicide for at least three (3) months prior to Visit 1 through completion of the subject's first menstrual cycle following the EOT Visit. * Stable hormonal contraceptive for at least three (3) months prior to Visit 1 through completion of the subject's first menstrual cycle following the EOT Visit. NOTE: For Depo-Provera injection contraceptives, the statement regarding first menstrual cycle following administration of the study product is not applicable as females receiving this form of contraception will not have menses. * In a monogamous relationship with a surgically sterilized (i.e., vasectomized) partner at least six (6) months prior to Visit 1. * Have undergone one of the following sterilization procedures at least six (6) months prior to Visit 1: Bilateral tubal ligation, Hysterectomy, Hysterectomy with unilateral or bilateral oophorectomy, Bilateral oophorectomy. 2. Unwillingness to submit a urine pregnancy test at screening if of childbearing potential. 3. Male subjects who refuse to use one of the following birth control methods: * Abstinence from the time of consent and through the duration of their participation in the protocol * Barrier method (condom or diaphragm) with spermicide from time of consent through the duration of their participation in the protocol * Surgical sterilization (vasectomy) at least 6 months prior to consent. 4. IOP greater than 29 mmHg in either eye. 5. Patients with high risk factors of ocular hypertension, such as thin central corneas, as identified by the Principal Investigator who may benefit from earlier treatment will be excluded. 6. Evidence of Angle closure. 7. Recent laser or incisional glaucoma surgery. 8. Subjects who are currently taking glaucoma medications. Subject who can safely stop taking these medications during washout period (4-6 weeks) may be considered. 9. Intranasal polyp or any head and/or neck neoplasm. 10. History of or evidence on physical examination including endoscopy of sinus or nasal pathology, nasal passage obstruction, chronic sinus infections, or severe seasonal allergies. 11. Currently using medications given intranasally. 12. Subject is taking any anticoagulant medication such as heparin, low molecular weight heparin, Coumadin, or antiplatelet agents including low dose aspirin. 13. History of stroke or Trans-Ischemic Attack (TIA) within the past five (5) years. 14. Neuro-cognitively impaired as assessed by the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS). 15. Subjects who have participated in an investigational product trial within the past 30 days. 16. Subjects who refuse any part of the protocol assessments.