Expert highlights long-term safety with Botox for bladder disorders

David A. Ginsberg, MD

At the 2021 International Continence Society Meeting, David A. Ginsberg, MD, presented results of a study investigating the long-term outcomes of onabotulinumtoxinA (Botox)in treating patients with overactive bladder (OAB) and urinary incontinence (UI).¹ In a recent interview, he discusses the success of this research and how it builds on outcomes of previous studies. Ginsberg is a Professor of Clinical Urology at the Keck School of Medicine at USC, in Los Angeles.

Please discuss the background for this study.

The background for this study was to get a better understanding of what we may see in regard to tolerability with men that are treated with onabotulinumtoxinA and what we see with them with long-term repeated treatments. Part of the challenge of evaluating the outcomes in men is that in most studies, the majority of participants are women. So, in each individual study, there is a much smaller percent of men involved. By doing this study, we were able to combine outcomes from several studies. This resulted with a greater number of men, allowing us to get meaningful outcomes in regard to how the men are doing.

What were some of the notable findings from this study? Were any of them surprising to you or your co-authors?

I don't think they were necessarily surprising to us. I think they made us feel that what we are doing is appropriate. We all know that onabotulinumtoxinA works for patients with refractory overactive bladder. We also know that for some patients—thankfully for most of them this is not the case—there is a risk of issues like incomplete emptying, UTI and the need to catheterize. And the concern is that there's going to be a greater issue in the male population. For those of us who do this a lot, I wouldn't say it was surprising because we've always treated men, but it was gratifying to see that indeed men do very well long term and we're not seeing more issues with adverse outcomes such as urinary retention or UTI, with long-term repeated treatments.

How do these findings build on previous research into this type of treatment?

We know that patients who have overactive bladder do well. And we know, again, that in most of those studies, the majority of patients are women. We've done long-term extension studies in patients getting onabotulinumtoxinA previously, but because there were so few men, we couldn't build upon that and come to significant conclusions in the male patient population. We knew with several other long term extension trials that if patients do well, we don't see an increased risk of side effects, increased risk of retention, or increased risk of UTI with repeat treatments. But, again, because there's a smaller percentage of men, the question is, "Can we say this with a higher level of confidence?" And doing this study allows us to say, "Yes, with repeat treatments, we're not seeing a greater risk of retention, and we're not seeing a greater risk of UTI." So, that was how that built upon prior studies that were done.

Based on these findings, are you likely to alter your own clinical practice in any way?

It's not going to change my practice. I've been very comfortable with onabotulinumtoxinA and I've been using it for a long time, using it well before it obtained FDA approval. I do hope this data would impact those practitioners that are hesitant to treat men with overactive bladder with onabotulinumtoxinA because they're worried about retention. I would hope they would see this data and say, "Okay, a majority of folks don't have retention, a majority of folks don't have a need to catheterize, a majority of folks don't have significant issues with infections, and it's a safe treatment in the majority of the appropriately selected patients that receive it both for men and women."

What is the take-home message for the practicing urologist?

This was an abstract that really looked at how well the treatment is tolerated, and there is another abstract that was authored by Victor Nitti [MD].² I think when you put these two abstracts together, the take-home is that men who are treated with onabotulinumtoxinA for overactive bladder do well. They have a significant improvement in their quality of life, and they have a low rate of issues like the need to catheterize and the need for additional therapies such as antibiotics for UTIs or other issues like that. So, to me, that's the take-home message. It's that men do well, and they don't have a really high risk of outcomes that we don't want them to have, and that the patients don't want to have, which is really the need to catheterize.

Is there anything else you feel our audience should know about the findings?

I think one of the challenges when we interpret this data is that the terminology that was used when these studies were first done, and it's one of those frustrations. The need for men or women to catheterize post-onabotulinumtoxinA was termed "urinary retention." And the reality is that very few patients go into retention, but that's the term that's being used if you have to catheterize even just once a day. So, understand that most patients, a majority of patients that actually need a catheter, don't go into urinary retention. That's actually very, very rare. The majority of patients that need to catheterize are catheterizing usually no more than once or twice a day in my practice. Thankfully, the majority of patients who get onabotulinumtoxinA don't need to use a catheter at all.

References

1. Ginsberg D, Chapple C, Kohan A, et al. Long-term, repeat treatments with onabotulinumtoxinA are well tolerated in male and female patients with overactive bladder and urinary incontinence: a pooled analysis of five clinical trials. Paper presented at: 2021 International Continence Society Meeting; October 14-17, 2021; virtual. Abstract #61

2. Nitti V, Ginsberg D, Kohan A, et al. OnabotulinumtoxinA is efficacious and well tolerated in male patients with overactive bladder and urinary incontinence: placebo-controlled treatment cycle 1 results from a pooled analysis of four randomized trials. Paper presented at: 2021 International Continence Society Meeting; October 14-17, 2021; virtual. Abstract #389