Phase 3 Study of Tadalafil Once-Daily in Asian Men With Benign Prostatic Hyperplasia (BPH)

Inclusion Criteria

• Present with benign prostatic hyperplasia (BPH; also referred to as BPH-LUTS), based on the disease diagnostic criteria, at study entry.
• Provide signed informed consent at study entry.
• Have BPH-LUTS with a Total International Prostate Symptom Score (IPSS) of ≥13 at beginning of placebo lead-in period.
• Have bladder outlet obstruction of intermediate severity as defined by a urinary peak flow rate (Qmax) of ≥4 to ≤15 milliliters per second (mL/sec) [from a prevoid total bladder volume (assessed by ultrasound) of ≥150 to ≤550 milliliters (mL) and a minimum voided volume of 125 mL] at beginning of placebo lead-in period.
• Have prostate volume ≥20 mL estimated by transabdominal or transrectal ultrasound at study entry.
• Agree not to use any other approved or experimental pharmacologic BPH, erectile dysfunction (ED) and/or overactive bladder (OAB) treatments, including alpha-blockers, 5-alpha reductase inhibitors (5-ARIs), phosphodiesterase type 5 (PDE5) inhibitors, or herbal preparations at any time during the study.
• Have not taken the following treatments within the indicated duration:
• Finasteride therapy for at least 3 months prior to beginning of placebo lead-in period.
• Dutasteride therapy for at least 6 months prior to beginning of placebo lead-in period.
• Anti-androgenic hormone therapy at least 12 months prior to beginning of placebo lead-in period.
• All other BPH therapy (including herbal preparations) for at least 4 weeks prior to beginning of placebo lead-in period.
• ED therapy for at least 4 weeks prior to beginning of placebo lead-in period.
• OAB therapy for at least 4 weeks prior to beginning of placebo lead-in period.
• Demonstrate compliance with study drug administration requirements during the placebo lead-in period by administering ≥70% of prescribed doses, confirmed by documentation that the participant returned ≤30% of prescribed doses at randomization.

Exclusion Criteria

• Prostate-specific antigen (PSA) >10.0 nanograms per milliliter (ng/mL) at study entry.
• PSA ≥4.0 to ≤10.0 ng/mL at study entry, if prostate malignancy has not been ruled out to the satisfaction of an urologist.
• Bladder postvoid residual (PVR) ≥300 mL by ultrasound determination at study entry.
• History of any of the following pelvic conditions (checked at study entry):
• Pelvic surgery or any other pelvic procedure, including radical prostatectomy, pelvic surgery for removal of malignancy, or bowel resection.
• Pelvic radiotherapy.
• Any pelvic surgical procedure on the urinary tract, including minimally invasive BPH-LUTS therapies and penile implant surgery.
• Lower urinary tract malignancy or trauma.
• Lower urinary tract instrumentation (including prostate biopsy) within 30 day of study entry.
• History of urinary retention or lower urinary tract (bladder) stones within 6 months of study entry.
• History of urethral obstruction due to stricture, valves, sclerosis, or tumor.
• Current neurologic disease or condition associated with neurogenic bladder (for example, Parkinson's disease, multiple sclerosis) at study entry.
• Clinical evidence of prostate cancer.
• Clinical evidence of any of the following bladder conditions:
• Mullerian duct cysts.
• Atonic, decompensated, or hypocontractile bladder.
• Detrusor-sphincter dyssynergia (contraction of the detrusor without sphincter relaxation).
• Intravesical obstruction (for example, intravesical median lobe of the prostate).
• Interstitial cystitis.
• Clinical evidence of any of the following urinary tract conditions at study entry:
• Urinary tract infection.
• Urinary tract inflammation (including prostatitis). Urinary tract infection/inflammation is defined as a positive result for leukocyte esterase from a urine dipstick or >5 white blood cells (WBCs) per high-powered field on urinalysis from a centrifuged, clean-catch, midstream urine specimen.
• Current antibiotic therapy for urinary tract infection.
• Clinically significant microscopic he