Intervention: (2-{7-[2-(4-Cyano-2-fluoro-phenoxy)-ethyl]-9-oxa-3,7-diaza-bicyclo[3.3.1]non-3-yl}-ethyl)-carbamic acid tert-butyl ester
Trial phase: Phase 2
SMILES: CC(C)(C)OC(=O)NCCN1CC2CN(CCOc3ccc(C#N)cc3F)CC(C1)O2
Sex: All
Age groups: Adult
Healthy volunteers: Accepts Healthy Volunteers
Participants at risk: 31
Group description: 1 drop in each eye, 1 hour post medically-induced mydriasis

Phentolamine Mesylate Ophthalmic Solution 1%: 1% phentolamine mesylate ophthalmic solution (Nyxol), a non-selective alpha-1 and alpha-2 adrenergic antagonist
Eligibility criteria:
Inclusion Criteria:

Males or females ≥ 18 and ≤ 45 years of age with brown irides (irises) only
Otherwise healthy and well controlled subjects
Able to comply with all protocol mandated procedures and to attend all scheduled office visits
Willing to give written informed consent to participate in this study

Exclusion Criteria

Clinically significant ocular disease as deemed by the Investigator (e.g., cataract, glaucoma, corneal edema, uveitis, severe keratoconjunctivitis sicca) that might interfere with the study
Unwilling or unable to discontinue use of contact lenses during treatment visits
Ocular trauma, ocular surgery or non-refractive laser treatment within the 6 months prior to screening
Ocular medication of any kind within 30 days of screening, with the exception of a) lid scrubs (which may have been used prior to, but not after screening) or b) lubricating drops for dry eye (preservative-free artificial tears), which may be used in between the study treatment days
Recent or current evidence of ocular infection or inflammation. Current evidence of clinically significant blepharitis, conjunctivitis, or a history of herpes simplex or herpes zoster keratitis at screening
History of diabetic retinopathy
Closed or very narrow angles that in the Investigator's opinion are potentially occludable if the subject's pupil is dilated
History of any traumatic (surgical or nonsurgical) or non-traumatic condition affecting the pupil or iris (e.g., irregularly shaped pupil, neurogenic pupil disorder, iris atrophy, iridotomy)
Known allergy or contraindication to any component of the mydriatic agents or the vehicle formulation
Known hypersensitivity or contraindication to α- and/or β-adrenoceptor antagonists (e.g., chronic obstructive pulmonary disease or bronchial asthma; abnormally low blood pressure (BP) or heart rate (HR); second- or third-degree heart blockage or Congestive Heart Failure (CHF); severe diabetes)
Clinically significant systemic disease (e.g., uncontrolled diabetes, myasthenia gravis, cancer, hepatic, renal, endocrine or cardiovascular disorders) that might interfere with the study
Initiation of treatment with or any changes to the current dosage, drug or regimen of any topical or systemic adrenergic or cholinergic drugs up to 7 days prior to screening, or during the study
Participation in any investigational study within 30 days prior to screening
Women of childbearing potential who are pregnant, nursing, planning a pregnancy, or not using a medically acceptable form of birth control. Acceptable methods include the use of at least one of the following: intrauterine device (IUD), hormonal (oral, injection, patch, implant, ring), barrier with spermicide (condom, diaphragm), or abstinence. An adult woman is considered to be of childbearing potential unless she is 1 year postmenopausal or 3 months post-surgical sterilization. All females of childbearing potential must have a negative urine pregnancy test result at Visit 1/Screening and Visit 2 examinations and must intend to not become pregnant during the study
Resting heart rate (HR) outside the normal range (50-110 beats per minute) at the Screening Visit. HR may be repeated only once if outside the normal range following at least a 5-minute rest period in the sitting position
Hypertension with resting diastolic BP > 105 mmHg or systolic BP > 160 mmHg at the Screening Visit. BP may be repeated only once if outside the specified range following at least a 5-minute rest period in the sitting position