Inclusion Criteria:
1. Male or female adults aged ≥19 years at the time of informed consent.
2. Diagnosis of primary open-angle glaucoma or ocular hypertension.
3. At the screening visit, subjects who meet any of the following:
* history of or current use of triple therapy, or
* history of or current use of dual therapy (dorzolamide and a topical beta-blocker), or
* inadequate IOP control despite current treatment, and who, in the investigator's judgment, have not achieved target IOP based on the degree of optic nerve damage and may benefit from additional IOP reduction with triple therapy.
4. Completion of an appropriate washout period for prior glaucoma medications before the randomization visit (based on the longest washout period among the components of prior medications):
\- Parasympathomimetics, oral or topical carbonic anhydrase inhibitors: 5 days
\- α-agonists: 14 days (brimonidine: 28 days)
* β-antagonists, prostaglandin analogues: 28 days
* Rho-kinase inhibitors: 28 days
5. Mean intraocular pressure (IOP) ≥21 mmHg in either eye at 8:30 AM (±1 hour) at the randomization visit (same eye as the study eye).
6. Ability to understand and voluntarily sign the informed consent form.
Exclusion Criteria:
1\. Subjects with any of the following comorbidities or conditions:
1. Central visual field defect with mean deviation (MD) ≤ -25 dB on visual field testing.
2. Chronic, recurrent, or severe inflammatory ocular disease (e.g., scleritis, uveitis, or herpetic keratitis).
3. Best-corrected visual acuity (BCVA) \< 0.25 (Han Chun Suk visual acuity chart) at both screening and randomization visits.
4. Any condition that prevents reliable intraocular pressure (IOP) measurement.
5. Other ocular pathology that, in the investigator's opinion, precludes use of the investigational product (e.g., severe dry eye).
6. Conditions requiring additional topical or systemic IOP-lowering medications during the study.
7. Reactive airway disease, including bronchial asthma or history thereof, bronchospasm, or severe chronic obstructive pulmonary disease.
8. Sinus bradycardia, second- or third-degree atrioventricular block, overt heart failure, cardiogenic shock, sick sinus syndrome, or sinoatrial block.
9. Severe renal impairment (creatinine clearance \<30 mL/min) or hyperchloremic acidosis.
10. Untreated pheochromocytoma.
11. Any severe disease that, in the investigator's judgment, renders the subject unsuitable for the study.
2\. History of the following conditions or procedures (including surgery):
1. Ocular trauma or ocular surgery within 24 weeks prior to screening (cataract surgery performed \>8 weeks prior is not excluded).
2. Ocular infection or ocular inflammation within 12 weeks prior to screening (within 8 weeks for simple conjunctivitis).
3. Ocular laser surgery within 12 weeks prior to screening.
3\. Prior or concomitant medications:
1. Oral beta-blockers within 4 weeks prior to randomization.
2. Addition of antihypertensive agents that may affect IOP within 4 weeks prior to randomization (excluding beta-blockers; e.g., calcium channel blockers, ACE inhibitors), unless the regimen has been stable for at least 7 days prior to screening.
3. α-adrenergic agonists, MAO inhibitors, or antidepressants affecting norepinephrine transmission within 2 weeks prior to randomization.
4. Topical ocular or periocular corticosteroids within 2 weeks prior to randomization.
5. Systemic corticosteroids within 4 weeks prior to randomization.
6. Intravitreal or sub-Tenon corticosteroid injection within 24 weeks prior to randomization.
4\. Subjects requiring contact lens use during the study period. 5. Known hypersensitivity, in the investigator's opinion, to any component of the investigational product or ophthalmic diagnostic eye drops.
6\. Use of any investigational drug or device within 4 weeks prior to screening (subjects participating in non-interventional studies such as observational studies or PMS may be enrolled).
7\. Pregnant or breastfeeding women. 8. Women and men of childbearing potential who are unwilling to use medically acceptable contraception or who plan pregnancy during the study period.
Acceptable contraception methods:
Hormonal contraceptives (oral, injectable, implantable, etc.) Intrauterine device (IUD) or intrauterine system (IUS) Surgical sterilization (e.g., vasectomy, hysterectomy, bilateral oophorectomy, bilateral salpingectomy) Sexual abstinence (only absolute abstinence is acceptable; periodic abstinence methods such as calendar, basal body temperature, ovulation methods, withdrawal, or barrier methods are not acceptable unless investigator-deemed strict abstinence is appropriate based on age, occupation, lifestyle, or sexual orientation)
