Efficacy and Safety of Vibegron Add-On Therapy for Persistent Overactive Bladder Symptoms in Benign Prostatic Hyperplasia Patients With α1-Blocker Treatment: A Multi-Center Prospective Randomized Controlled Study (VATON Study).

OBJECTIVES

To evaluate the efficacy and safety of vibegron add-on therapy for persistent overactive bladder (OAB) symptoms after α1-blocker monotherapy for benign prostatic hyperplasia (BPH).

METHODS

Eligible patients were aged ≥ 50 years and diagnosed with BPH. All patients had received an α1-blocker for ≥ 8 weeks, yet had persistent OAB symptoms. Patients were randomized 1:1 to receive add-on vibegron (50 mg) or to continue α1-blocker monotherapy. The primary efficacy endpoint was the between-group difference from baseline (week 0) to week 12 in total overactive bladder symptom score (OABSS). Secondary endpoints included bladder diary parameters, OABSS subscores; International Prostate Symptom Score total, storage/voiding, quality-of-life score; and patient satisfaction assessed by the Patient Global Impression. Safety was assessed by recording treatment-emergent adverse events.

RESULTS

Overall, 158 patients were randomized into two groups (n = 79 each). The least-squares mean change in the primary endpoint (OABSS total score) was -1.9 (95% confidence interval [CI]: -2.4 to -1.5) with α1-blocker monotherapy and -3.3 (95% CI: -3.8 to -2.9) with vibegron add-on therapy; the between-group difference was -1.4 (95% CI: -2.0 to -0.8; p < 0.001), indicating a significant improvement with add-on therapy. Across the secondary endpoints, favorable outcomes were observed. Higher satisfaction was reported in the vibegron add-on therapy group than in the α1-blocker monotherapy group. Vibegron was well tolerated, and no serious drug-related treatment-emergent adverse events were observed.

CONCLUSIONS

Vibegron add-on therapy to an α1-blocker may be effective and safe for treating BPH with persistent OAB symptoms.