InterStim Micro device shows safety and efficacy in overactive bladder at 6 months

In this video, Colin Goudelocke, MD, shares notable findings from the Neurourology and Urodynamics study, “Evaluation of clinical performance and safety for the rechargeable InterStim Micro device in overactive bladder subjects: 6-month results from the global postmarket ELITE study.” Goudelocke is a urologist with Ochsner Health Center in New Orleans, Louisiana.

Transcription:

The aim of this study was to look at the safety and the clinical efficacy of the device. And certainly not surprising, but maybe reassuring more than anything was that the device was safe. At 6 months, we didn't have any unanticipated adverse device events. There was 1 what we classify as a serious adverse device event, which means anytime there's any kind of significant intervention. There was 1 patient who had some pain at the site of the device. That resolved with a surgical revision of the device. That's 1 patient out of 68. And that really tracks with what we see in the primary cell data. Remember, we're comparing this new device to what we've been doing for 25 years. And there's certainly some advantages to it. But first, we want to make sure that it is as safe as the device that we've been using for 25 years. And it does appear to be, at least at 6 months, but we'll continue to follow these patients up to 2 years so that we can make sure. The other thing that is important in a study like this is to make sure that not only we have clinical efficacy, but that we have clinical efficacy over time. This is an intermediate snapshot at how this device is performing; obviously, we want to watch that and see if that holds up over 2 years. But we do see that the device appears to be clinically efficacious. At 3 months, on average, we saw a reduction of about 3.6 incontinence episodes per 24 hours. At 6 months, that held up; it's 3.7 incontinence episodes. The frequency of voids went from about 4.5 fewer voids per day at 3 months, and then at 3 months, it's 4.4 fewer voids per day. What's really encouraging to me is that the improvement that we see at 3 months is maintained at 6 months. What I really want to see is do we see that improvement maintained at 2 years. For people like me that do a lot of these, there's always been a little bit of a sense that maybe we've seen some fall-off in the efficacy of neuromodulation over time, but at 6 months, that doesn't seem to be the issue here. Patients have the same objective improvement at 6 months that they had at 3 months. That's reassuring. One of the arguments why people like me perceived the possibility of decreasing efficacy over time, is that maybe patients' perceptions of their improvement are migrating or changing. So when I had this device first put in, I had been leaking 6 times a day. Now I'm leaking twice a day, and I perceive that as this huge improvement. And that certainly is a huge improvement. But maybe it's 6 months later, now I'm starting to get aggravated by the fact that I'm still leaking twice a day. So the other thing I think was really important is to look at how patients do over time. And, frankly, we see at 6 months that the satisfaction rates, the quality-of-life indicators, those sorts of things, appear to be maintained. Almost 90% of these patients still feel like their symptoms are improved 6 months into this. And that perception of migrating expectations may not be true for this device. In terms of surprising results, I don't think there's anything in the trial data that's really surprising to me. I do think one of the things that is a little bit unexpected is looking at the bigger picture. I mentioned that the Micro device—and there are similar devices that are produced by other companies; the Micro is not the only rechargeable sacral neuromodulator on the market—but the Micro and similar devices came about to solve a problem that we have these primary cell batteries where you start off with a certain amount of energy and it runs down over time. And we were getting 5, 6, 7 years out of these devices. What I think is a little surprising is that almost at the same time, within a few months of this device being produced, the primary cell batteries got much better. So whereas we maybe used to be able to get 5 or 6 or 7 years out of a battery, now, the next iteration of that battery, depending on the model or brand, if you will, we might get 15 to 20 years out of that primary cell device. It was a little bit surprising how quickly the old battery technology caught up to the new battery technology. We expect to get about 15 years out of a Micro device. But now, we also expect to get about 15 years out of that primary cell. So the idea of decreasing battery changes over time becomes less important. But size still becomes really important, right? Because the primary cell battery that now can last 15 or more years, it's still the same size that it used to be, and this Micro battery, which is 80% smaller, is still that same size. So one of the things that's been a little bit of a surprise is the shift toward the importance of size. Because for a patient trying to make a decision between these devices, the reasons why he or she may want a small device as opposed to the somewhat larger standard devices becomes more important.

This transcription was edited for clarity.