Intra-Trigonal Onabotulinum Toxin A improves bladder symptoms and quality of life in Bladder Pain Syndrome /Interstitial Cystitis patients - a pilot, single centre, randomized, double-blind, placebo-controlled trial

To compare efficacy and safety of trigonal injections of onabotulinumtoxinA and saline in Bladder Pain Syndrome/Interstitial Cystitis patients.

This phase II study enrolled women with Bladder Pain Syndrome/Interstitial Cystitis >6months and pain ≥4 in 0-10 visual analogue scale, refractory to common treatment. OnabotulinumtoxinA 100U (n=10) or saline (placebo, n=9), were administered as 10 trigonal injections of 1ml. Primary end-point was change from baseline in pain intensity reported at week 12. Additional end-points included O´Leary-Sant scores, micturition frequency, quality of life at week 4, 8 and 12 and treatment benefit scale at week12. Safety assessments included urinary tract infections, post-void residue and initiation of clean intermittent catheterization.

At week12, onabotulinumtoxinA significantly reduced pain compared with saline (-3.8±2.5 versus -1.6±2.1, p<0.05). The proportion of patients who achieved ≥50% reduction in visual analogue scale for pain was 60% with onabotulinumtoxinA versus 22% with placebo. OnabotulinumtoxinA significantly improved O´Leary-Sant scores and quality of life over placebo at weeks 4, 8 and 12. Important numeric reductions in voiding frequency were also observed with the toxin. OnabotulinumtoxinA was well tolerated. Three urinary tract infections occurred with onabotulinumtoxinA versus 2 with saline. Mean post-void residue at week12 was 5±13ml with onabotulinumtoxinA versus 0ml with saline. This study suffers the limitations inherent to a single-center trial with a small number of patients enrolled.

OnabotulinumtoxinA 100U caused significant and clinically relevant improvements in bladder pain and quality of life in Bladder Pain Syndrome/Interstitial Cystitis patients refractory to common therapy and was well tolerated.

The Journal of urology. 2017 Oct 12 [Epub ahead of print]

R Pinto, D Costa, A Morgado, P Pereira, A Charrua, J Silva, F Cruz

Department of Urology, Hospital de S. João, Porto, Portugal; Faculty of Medicine of Porto, Portugal; Instituto de Investigação e Inovação em Saúde (i3S), Porto, Portugal., Department of Urology, Hospital de S. João, Porto, Portugal., Department of Urology, Hospital de S. João, Porto, Portugal; Faculty of Medicine of Porto, Portugal., Faculty of Medicine of Porto, Portugal; Instituto de Investigação e Inovação em Saúde (i3S), Porto, Portugal.