Here we present the final results from an extension study assessing long-term onabotulinumtoxinA treatment (3.5 years) in patients with idiopathic overactive bladder.

Patients who completed either of 2 Phase III trials were eligible to enter a 3-year extension study in which they received multiple onabotulinumtoxinA (100 U) treatments. Data were analyzed for the overall population of patients who received 100 U in any treatment cycle (n=829) and within discrete subgroups of patients who received exactly 1 (n=105), 2 (n=118), 3 (n=117), 4 (n=83), 5 (n=46), or 6 (n=33) treatments of the 100 U dose throughout the study (n=502).

Of the 829 patients enrolled, 51.7 % completed the study. Discontinuations due to AEs/lack of efficacy were low (5.1/5.7 %); other reasons were not treatment-related. Mean reductions from baseline in urinary incontinence (UI) episodes/day (week 12; co-primary endpoint) were consistent among discrete subgroups who received 1 (–3.1), 2 (–2.9, –3.2), 3 (–4.1 to –4.5), 4 (–3.4 to –3.8), 5 (–3.0 to –3.6), or 6 (–3.1 to –4.1) treatments. A consistently high proportion of patients reported improvement/great improvement on the Treatment Benefit Scale (week 12; co-primary endpoint) in the discrete subgroups across all treatments (70.0–93.5 %). Median time to request retreatment was ≤6 months for 34.2 %, >6–≤12 months for 37.2 %, and >12 months for 28.5 % of patients. Most common AE was UTI, with no changes in safety profile over time.

Long-term onabotulinumtoxinA treatment resulted in consistent reductions in UI and high proportions of patients reporting improvement after each treatment, with no new safety findings.