BACKGROUND: Botulinum toxin treatment has been investigated as a minimally invasive alternative to oral medications in men with lower urinary tract symptoms (LUTS) suggestive of benign prostatic hyperplasia (LUTS/BPH).
OBJECTIVE: To explore the efficacy of onabotulinumtoxinA 100 U, 200 U, and 300 U versus placebo in men with LUTS/BPH in a phase 2 dose-ranging study.
DESIGN, SETTING, AND PARTICIPANTS: A multicenter double-blind randomized, placebo-controlled 72-wk study enrolled men ≥50 yr of age with LUTS/BPH, International Prostate Symptom Score (IPSS) ≥12, total prostate volume (TPV) 30-100ml, and maximum flow rate (Qmax) 5-15ml/s.
INTERVENTION: Single transperineal (n=63) or transrectal (n=311) administration of placebo (n=94) or onabotulinumtoxinA 100 U (n=95), 200 U (n=94), or 300 U (n=97) into the prostate transition zone.
OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: The primary efficacy end point was a change from baseline in IPSS at week 12. Secondary end points were Qmax, TPV, and transition zone volume (TZV). Analysis of covariance and the Cochran-Mantel-Haenszel method assessed the efficacy and proportion of IPSS responders. Adverse events (AEs) were assessed.
RESULTS AND LIMITATIONS: Significant improvements from baseline in IPSS, Qmax, TPV, and TZV were observed for all groups, including placebo, at week 12 (p< 0.001), with no significant differences between onabotulinumtoxinA and placebo. However, in an exploratory post hoc analysis, a significant reduction in IPSS versus placebo was observed with onabotulinumtoxinA 200 U in prior α-blocker users (n=180) at week 12. AEs were comparable across all groups.
CONCLUSIONS: Reductions in LUTS/BPH symptoms were seen in all groups, including placebo, with no significant between-group differences owing to a large placebo effect from the injectable therapy. The findings from the post hoc analysis in men previously treated with α-blockers will be further explored in an appropriately designed study.
Written by:
Marberger M, Chartier-Kastler E, Egerdie B, Lee KS, Grosse J, Bugarin D, Zhou J, Patel A, Haag-Molkenteller C. Are you the author?
Medical University of Vienna, Vienna, Austria.
Reference: Eur Urol. 2013 Mar;63(3):496-503.
doi: 10.1016/j.eururo.2012.10.005
PubMed Abstract
PMID: 23098762
