Long-term treatment of older patients with overactive bladder using a combination of mirabegron and solifenacin: a prespecified analysis from the randomized, phase III SYNERGY II study.

Aims: SYNERGY II was a 12-month phase III trial in patients with overactive bladder (OAB) symptoms that investigated the safety and efficacy of the combination of mirabegron and solifenacin in comparison with each monotherapy. This analysis evaluated the trial findings using four age subgroups (<65, ≥65, <75, and ≥75 years).

Methods: Eligible patients were ≥18 years with symptoms of "wet" OAB (urinary frequency and urgency with incontinence) for ≥3 months. Patients were randomized to receive once-daily solifenacin succinate and mirabegron (5 mg/50 mg; combination), solifenacin succinate, or mirabegron (4:1:1). Safety evaluations: treatment-emergent adverse events (TEAEs), vital signs, and electrocardiogram, post-void residual volume, and laboratory assessments. Primary efficacy variables: change from baseline to end of treatment in number of incontinence episodes/24 h and micturitions/24 h.

Results: Of 1794 patients (full analysis set), 614 (34.2%) and 168 (9.4%) were ≥65 and ≥75 years old, respectively. Overall, 856 (47.2%) patients experienced ≥1 TEAE. Higher TEAE incidences were typically observed for the combination versus both monotherapies (eg, constipation) and in the older versus younger age groups (eg, urinary tract infection). Increases in mean pulse rate from baseline of >1 bpm were noted in the combination and mirabegron younger age groups only. No clinically significant findings were observed in the other safety parameters. The efficacy variables improved with all treatments and the greatest improvements were typically observed with combination therapy.

Conclusions: Mirabegron and solifenacin combination therapy was a well-tolerated and effective treatment for patients with OAB symptoms irrespective of their age.