Xenon Pharmaceuticals Inc. (NASDAQ:XENE) Q4 2022 Earnings Call Transcript

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Ian Mortimer: Great. Thank you. Maybe I can start a little bit on the Phase 3 patient population and then add in and then specifically, why don’t we get into a few details on urinary retention and at least what we’re seeing with those two patients in open-label extension, which I think is maybe the more relevant data just because they’ve been on the drug a lot longer. So, on the Phase 3 patient population, actually, if we look at Phase 2 and we’ve published this data, we published it initially at the Ascent Neurotherapeutic conference about a year ago where we published tables of the anti-seizure medicines that these patients had either failed or that they were on study. And you’ll see it’s a really long list. So, I don’t think there’s any kind of standard-of-care of these types of patients that are coming into our study.

And so I think we will see similar in Phase 3 that patients will be on a wide variety of drugs coming into the study, and there’ll be a wide variety that they would have failed prior to coming into study. But Chris, I don’t know if you have any specific comments around BRIVIACT or XCOPRI and then if you want to move to the urinary retention comments?

Chris Kenney: You are referencing Chris Von Seggern for the BRIVIACT or XCOPRI I assume?

Ian Mortimer: No, no, I was — no, I was passing it to you, Chris, Kenny.

Chris Kenney: Okay. Sorry, I misunderstood. Yes. So, I mean, as far as like sort of predicting whether that’s going to cause a change in the Phase 3, I mean, it’s early days with the Phase 3. So I think it’s — it would be too early to say. I wouldn’t be surprised if there’s somewhat of an uptick in XCOPRI in our Phase 3 program relative to the Phase 2 program, but we just don’t have — we haven’t put in enough time to be able to say one way or another. As far as the urinary retention, there were the two patients that you mentioned in the open-label. And I think you were kind of pointing to the fact that it seems like a bit of a misnomer. So, if someone were to have complete urinary retention, then obviously, that would have to be fixed, right, with catheterization or some kind of permanent procedure.

And none of these patients had any issue to the extent that it required catheterization. So, it’s obviously not complete urinary retention. But that’s how it was coded in Phase 2. Now, going forward into Phase 3, we have — we’re going to be following this adverse event very closely in a very systematic way so that there’s — if something like this is reported, there’s an immediate feedback between the sponsor in a site to kind of get to the bottom of well is this really urinary retention or not? Is it urinary hesitancy instead, et cetera? So, yes, we have — we’re actively approaching Phase 3 more systematic than we did Phase 2 for that very reason that you brought up.

Ian Mortimer: And just to add to Chris’ comment, I mean, with the two patients that we saw that were coded to urinary retention, in the double blind and then two different patients in open-label. Obviously, those two patients in open-label, we had talked about those patients quite some time ago, and we haven’t seen any additional coding to urinary retention when we’ve done additional cuts of the data. And just to reemphasize Chris’ point, none of these patients have needed any intervention whatsoever. So, we think that it’s definitely not — even if they have some urinary symptoms, it’s definitely not retention in the sense of not being able to avoid at all.

Joseph Thome: Perfect. Thank you very much.

Ian Mortimer: Yes.

Operator: Our next question comes from the line of from Bank of America. Please proceed.

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