Intradetrusor injection of onabotulinumtoxin A (OnaBoNT-A) may be safe and effective for patients with overactive bladder, according to a study published in the Journal of Urology.
Pradeep Tyagi, PhD, and colleagues identified peer-reviewed basic and clinical research studies of OnaBoNT-A in the treatment of patients with neurogenic bladder and refractory idiopathic overactive bladder published between March 2000 and March 2016. The review yielded more than 50 articles relevant to the approach of injection-free OnaBoNT-A chemodenervation.
The researchers found that the efficacy and safety of intradetrusor injection of OnaBoNT-A for the treatment of overactive bladder are sensitive to injection volume and depth, which led to further studies of injection-free modes of drug delivery into the bladder.
Urothelial denudation with protamine sulfate or dimethyl sulfoxide, liposome encapsulated OnaBoNT-A, and other physical approaches are being studied to increase toxin permeability and avoid intradetrusor injections. In addition, liposome encapsulated OnaBoNT-A enhances toxin activity while reducing its toxin degradation. In a multicenter, placebo controlled study, investigators tested the safety and efficacy of liposome encapsulated OnaBoNT-A. Although this treatment successfully reduced urinary frequency and urgency, it did not significantly reduce urgency urinary incontinence episodes.
Intradetrusor injection of OnaBoNT-A is a safe and effective treatment for overactive bladder, according to the researchers. Injection of the toxin into the bladder wall impairs afferent and efferent nerves, but injection-free drug delivery approaches only impair the bladder afferent nerves.
“Novel approaches to the injection-free delivery of onaBoNT-A have so far not demonstrated efficacy comparable to that of intradetrusor injection,” the authors stated. “However, continued research with a variety of approaches shows great promise.”
- Tyagi P, Kashyap M, Yoshimura N, et al. Past, Present and Future of Chemodenervation with Botulinum Toxin in the Treatment of Overactive Bladder. J Urol. April 2017. doi: 10.1016/j.juro.2016.11.092