Inclusion Criteria:
* Screening Eligibility Criteria:
1. Men aged 45 years or older.
2. Participants diagnosed with benign prostatic hyperplasia (BPH).
3. Prostate volume of ≥30 mL as measured by transrectal ultrasonography (TRUS).
4. Participants considered capable of completing the questionnaires.
5. Participants who voluntarily agree to participate in the clinical trial and - provide written informed consent.
* Randomization Eligibility Criteria
1. Total International Prostate Symptom Score (total IPSS) of ≥13 points.
2. Maximum urinary flow rate (Qmax) of ≥4 mL/sec and ≤15 mL/sec, with a minimum voided volume of ≥125 mL.
3. Postvoid residual urine volume (PVR) of \<200 mL.
Exclusion Criteria:
1. Participants with hypersensitivity to the investigational medicinal product, its components, or sulfonamides.
2. Participants with any of the following medical histories:
* Malignancy of the pelvic organs (bladder, prostate, or rectum).
* Prostate surgery or other invasive procedures (e.g., robotic simple prostatectomy, radiofrequency therapy, or minimally invasive treatment).
* Urethrotomy or other surgery that may affect urinary flow, or pelvic surgery.
* Lower urinary tract instrumentation within 4 weeks prior to screening.
* Acute urinary retention within 12 weeks prior to screening.
* Symptomatic orthostatic hypotension.
* Known alcohol or drug abuse.
3. Participants with any of the following comorbidities:
* Major depressive disorder.
* Clinically significant arrhythmia.
* Uncontrolled hypertension (systolic blood pressure \>170 mm Hg or diastolic blood pressure \>100 mm Hg).
* Uncontrolled hypotension (systolic blood pressure \<90 mm Hg or diastolic blood pressure \<50 mm Hg).
* Uncontrolled diabetes mellitus (HbA1c \>9.0%).
* Galactose intolerance, Lapp lactase deficiency, or glucose-galactose malabsorption.
* Severe renal impairment (estimated glomerular filtration rate \[eGFR\] \<30 mL/min according to the Chronic Kidney Disease Epidemiology Collaboration \[CKD-EPI\] equation).
* Severe hepatic impairment (AST and/or ALT \>3 × ULN).
* Conditions other than BPH that may cause voiding dysfunction or changes in urinary flow (e.g., neurogenic bladder, bladder neck sclerosis, urethral stricture, bladder tumor, acute or chronic prostatitis, or acute or chronic urinary tract infection).
4. PSA \>4.0 ng/mL, unless a prostate biopsy performed within 6 months prior to randomization confirms the absence of prostate cancer.
5. Participants who underwent a prostate biopsy within 4 weeks prior to screening. Participants may be eligible if more than 4 weeks have elapsed since the biopsy.
6. Participants who have received or are receiving any of the following medications or foods within the specified periods prior to randomization:
* α-blockers (tamsulosin, terazosin, doxazosin, alfuzosin, etc.): within 4 weeks prior to randomization.
* PDE5 inhibitors (tadalafil, sildenafil, vardenafil, udenafil, mirodenafil, avanafil, etc.): within 4 weeks prior to randomization.
* 5α-reductase inhibitors (finasteride, dutasteride):
1. Finasteride: within 12 weeks prior to randomization.
2. Dutasteride: within 24 weeks prior to randomization.
* Antimuscarinic/anticholinergic agents (oxybutynin, propiverine, solifenacin, tolterodine, trospium, etc.): within 4 weeks prior to randomization.
* β3-adrenergic agonists (mirabegron, vibegron): within 4 weeks prior to randomization.
* Progestogen preparations: within 24 weeks prior to randomization.
* Medications with antiandrogenic effects other than progestogen preparations (spironolactone, flutamide, bicalutamide, cimetidine, ketoconazole, etc.): within 24 weeks prior to randomization.
* Strong CYP3A4 inducers (carbamazepine, phenytoin, rifampin, St. John's wort, etc.): within 4 weeks prior to randomization.
* Strong CYP3A4 inhibitors (clarithromycin, lopinavir/ritonavir, ritonavir, ketoconazole, itraconazole, grapefruit, grapefruit juice, etc.): within 4 weeks prior to randomization.
* Desmopressin: within 4 weeks prior to randomization.
* Cholinergic agents (bethanechol, carbachol, etc.): within 4 weeks prior to randomization.
7. Participants who have received an investigational medicinal product or investigational medical device within 4 weeks or 5 half-lives, whichever is longer, prior to screening.
8. Participants who do not agree to use the contraception methods permitted in this clinical trial (see Section 8.4.6.1) or to refrain from sperm donation during the clinical trial and for 30 days after the last administration of the investigational medicinal product.
9. Participants who intend to donate blood during the clinical trial or for 30 days after the last administration of the investigational medicinal product.
10. Participants who are considered unsuitable for participation in the clinical trial by the investigator for other reasons.
