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Xenon Pharmaceuticals Inc
NASDAQ:XENE

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Xenon Pharmaceuticals Inc
NASDAQ:XENE
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Price: 39.8 USD -1.34% Market Closed
Updated: May 19, 2024

Earnings Call Transcript

Earnings Call Transcript
2021-Q4

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Operator

Thank you for standing by and welcome to Xenon Pharmaceuticals 2021 Year End Financial Results Call. [Operator Instructions] I would now like to hand the conference over to your host, Sherry Aulin, Chief Financial Officer of Xenon Pharmaceuticals. Please go ahead.

S
Sherry Aulin
Chief Financial Officer

Good afternoon. Thank you for joining us on our call and webcast to discuss Xenon’s year end 2021 financial and operating results. Joining me are Ian Mortimer, Xenon’s President and Chief Executive Officer; Dr. Chris Kenney, Xenon’s Chief Medical Officer; and Dr. Chris Von Seggern, Xenon’s Chief Commercial Officer. Please be advised that during this call, we will make a number of statements that are forward-looking, including statements regarding the research and clinical development plans and timelines and results of operations, the timing of and results from clinical trials and preclinical development activities of our proprietary and partnered product candidates, the potential efficacy, safety profile, future development plans, addressable market, regulatory success and commercial potential of our proprietary and partnered product candidates, the anticipated timing of IND or IND equivalent submissions and the initiation of future clinical trials for our proprietary products and those related to other partnered candidates, the efficacy of our clinical trial designs, our ability to successfully develop our proprietary development programs, the timing and results of our and our collaborators’ interactions with regulators, the timing and anticipated enrollment in our clinical trials, the potential receipt of milestone and royalties from our collaborators, our expectation of having sufficient cash to fund operations into at least 2024, and the timing of potential publication or presentation of future clinical data. Forward-looking statements are subject to numerous risks and uncertainties, many of which are beyond our control, including the risks and uncertainties described from time-to-time in our SEC filings. Our results may differ materially from those projected on today’s call. We undertake no obligation to publicly update any forward-looking statement. Today’s press release summarizing Xenon’s year end 2021 financial results and the accompanying annual report on Form 10-K will be made available under the Investors section of our website at www.xenon-pharma.com and filed with the SEC and on SEDAR. Now, I’d like to turn the call over to Ian.

I
Ian Mortimer
President and Chief Executive Officer

Thanks, Sherry. Good afternoon, everyone. Thanks for joining our call. Today, I will provide a high level update on our partnered and proprietary programs and then I will turn the call over to Chris Kenney, who will provide additional color around our plans for XEN1101 moving forward. Sherry will conclude our call by briefly summarizing our financial results and anticipated key milestone events ahead. Chris Von Seggern is also on the call to provide his perspective during the Q&A. Overall, when we look back on 2021, we are proud of the significant progress we made across our proprietary drug development pipeline and partnered programs, including the transformational event of the positive readout of strong efficacy data from our XEN1101 Phase 2b X-TOLE clinical trial. We enter 2022 with incredible momentum with multiple mid to late-stage clinical programs and important milestone opportunities throughout the year, which we will discuss today. I will start by briefly touching on our partnered programs. In November, Pacira Biosciences completed its acquisition of Flexion Therapeutics, along with the rights to develop and commercialize XEN402, a Nav1.7 inhibitor. XEN402 has been formulated for extended-release from a thermosensitive hydrogel and is now known as PCRX301. Pacira has indicated that they expect data in the second quarter of this year from a Phase 1b proof-of-concept trial that is evaluating the safety and tolerability of PCRX301 administered as a single dose in patients undergoing bunionectomy. In addition, I am pleased to report that our partnered programs with Neurocrine Biosciences also continue to advance through development. In January, we received a $15 million regulatory milestone under our collaboration and Neurocrine now has two separate Phase 2 trials underway, evaluating NBI-921352 in adult patients with focal onset seizures and pediatric patients with SCN8A related epilepsy. We look forward to keeping you updated as these partnered programs reach important milestones. Within our proprietary pipeline, we continue to enroll patients in our pediatric XEN496 Phase 3 EPIC clinical trial. This Phase 3 randomized, double-blind, placebo-controlled parallel group global multi-center clinical trial is evaluating the efficacy, safety and tolerability of XEN496 in approximately 40 pediatric patients aged 1 month to less than 6 years with KCNQ2-DEE. Based on published physician case studies with ezogabine and its Kv7 mechanism of action, we believe that XEN496 has the potential to address an important unmet medical need for these young patients. As the EPIC trial continues to expand through the onboarding of new sites and new geographical jurisdictions, our clinical team is anticipating the study completion in the first half of 2023. We also continue to make meaningful progress within our XEN1101 program and have spent considerable time from our X-TOLE top line data in October 2021, analyzing and presenting additional subgroup analyses, building out a robust PK/PD model, evaluating interim safety data in the X-TOLE open-label extension study and completing our planning for our Phase 3 program. This is all in preparation for our anticipated end-of-Phase 2 meeting with FDA in Q2 of this year and expected initiation of our Phase 3 program in the second half of the year. Before passing the call to Chris, we have had some questions recently from investors on the Biohaven KCNQ preclinical Kv deal. We haven’t discussed the XEN1101 preclinical data in some time, but we are happy to provide our perspective as these questions have come up. The first question we have received is the activity of XEN1101 on GABAA. XEN1101 has no activity on GABAA at 10 micromolar. These experiments on XEN1101 have been conducted at established CRO labs and are also included in our regulatory filings supporting our clinical studies. And just to put this into context, 10 micromolar is approximately 50-fold higher than the concentrations we reached clinically, so we have no reason to believe that XEN1101 has any GABA activity in a human contributing to either the efficacy or the tolerability of XEN1101. The second question we have received is around in vivo pharmacology and therapeutic index. Comparison across experiments are always challenging and the data presented on their Kv compound BVH7000 is in a different preclinical species and with different toxological measures than the data they showed for XEN1101 or ezogabine. We have chosen to use a much broader number of preclinical efficacy models and we focused on data generated in the mouse MES model as the EC50s in this model predicts well the concentrations required to see efficacy in human clinical trials. And this has now been validated with both ezogabine and XEN1101. The BVH7000 efficacy data presented is in the rat MES model. Rats are known to show efficacy in this model at significantly lower concentrations for the Kv mechanism in the mouse. We see roughly a fourfold leftward shift in our EC50s in the rat MES model for the Kv mechanism. So bottom line, data generated using different pre-clinical species and different experimental endpoints cannot be compared. But now moving back to our XEN1101 clinical program, in summary, we have considerable data supporting the role that XEN1101 could play in treating adult patients with focal epilepsy. The XPO clinical results demonstrated substantial efficacy in a difficult-to-treat patient population with even more impressive efficacy in subgroup analyses of patients with less severe disease. A tolerability profile consistent with an active CNS drug, additional clearly differentiating attributes, including an only-in-class mechanism, dosing of one pill once a day with no titration required. Feedback from KOLs and from our proprietary market research supports our belief that XEN1101 has the potential to significantly improve the current standard of care for patients with residual seizure burden, and if approved, would represent a meaningful advancement in the therapeutic armamentarium for this disease. On that note, I’d like to turn the call over to Chris Kenney, who can provide an update on where we are with our Phase 3 plans for XEN1101 and also on our other Phase 2 proof-of-concept studies running in parallel. Chris?

C
Chris Kenney
Chief Medical Officer

Yes. Thanks, Ian. Appreciate it. On our last call, which is our American Epilepsy Society presentations, we outlined additional encouraging data generated from our deep dive into the X-TOLE data. As we continue to complete additional data analysis, our confidence grows in the high potential we envision for XEN1101 to address important unmet needs. Tomorrow, Dr. Jacqueline French will present an encore presentation of the Phase 2b X-TOLE data at the Ascent 2022 Annual Meeting hosted by the American Society for Experimental Neurotherapeutics. We also have a second presentation in a poster format, summarizing several sub-analyses addressing the impact of disease severity that suggests efficacy maybe more robust in patients with less severe disease burden. I encourage you to access these posters on the Xenon website following this event. Given its robust efficacy, along with an AE profile in line with other anti-seizure medications, we are excited to move forward with our Phase 3 plans for XEN1101. We remain on track to conduct an end-of-Phase 2 meeting with the FDA during the second quarter of this year. This meeting represents a key milestone for our XEN1101 program. The objectives for this meeting are to obtain agreement on our Phase 3 program and the overall data package needed for NDA filing. We will also discuss with the FDA the opportunity for X-TOLE to be considered a pivotal trial. We anticipate that our future development plans include two Phase 3 trials in adult focal epilepsy with the first of these Phase 3 trials in the second half of the year. After the end-of-Phase 2 meeting, we intend to engage European regulators through scientific advice to obtain their agreement on the XEN1101 Phase 3 program. In addition to focal epilepsy, we are evaluating other epilepsy indications and expect to outline our plans in the coming months. Preclinical and clinical evidence exists around the Kv7 mechanism that supports a strong scientific rationale for developing XEN1101 in major depressive disorder, or MDD. We continue to support our collaboration with the School of Medicine at Mount Sinai. Patient enrollment is underway with their investigator-sponsored Phase 2 proof-of-concept, placebo-controlled clinical trial of XEN1101 in approximately 60 patients for the treatment of major depressive disorder and anhedonia. In addition, an investigational new drug or IND application has been submitted to FDA to support our plans for a larger Xenon-sponsored clinical study in MDD with XEN1101, which is expected to be initiated in the first half of this year. We look forward to providing the finalized trial design once the IND has been cleared and the study initiated. Overall, we have made tremendous progress on our XEN1101 program and we look forward to initiating the Phase 2 MDD trial in the near-term, followed by our Phase 3 program in focal epilepsy targeted for the second half of this year. I’d now like to ask Sherry to summarize our financial position and briefly recap our upcoming milestones. Sherry?

S
Sherry Aulin
Chief Financial Officer

Thanks, Chris. I am excited to see the immense amount of momentum in our business as we continue to prudently manage Xenon’s operations. As noted on our last quarterly call, I believe Xenon is well-capitalized to support our business objectives, the advancement of our clinical development programs as well as our preclinical and discovery programs. I will briefly touch on the highlights from this year’s financial statements. Cash and cash equivalents and marketable securities as of December 31, 2021 were $551.8 million compared to $177 million as of December 31, 2020. Subsequent to year end, we achieved a $15 million regulatory milestone under our collaboration with Neurocrine Biosciences. Based on current assumptions, which include fully supporting the planned XEN1101 and XEN496 clinical development programs as well as preclinical and discovery programs, we anticipate having sufficient cash to fund operations into at least 2024, excluding any revenue generated from existing partnerships or potential new partnering arrangements. I’d refer you to our news release and 10-K report filed today for further details from our financial statements. Looking ahead, there are number of key objectives and milestone opportunities in our pipeline. As noted by Chris, we anticipate conducting an end-of-Phase 2 meeting with the FDA in the second quarter of 2022 to support the initiation of our Phase 3 development program for XEN1101 expected in the second half of the year. Post our end-of-Phase 2 meeting and receipt of final FDA minutes, we anticipate being in a position to share our final Phase 3 plans for XEN1101. In parallel, we will continue to evaluate and plan for an XEN1101 program in another epilepsy indication and expect to be in a position to outline our plans in the coming months. We will provide continued support for the ongoing investigator-led study examining XEN1101 and MDD and expect to initiate our own company-sponsored MDD clinical study in the near-term with our IND recently filed. With the ongoing advancement of our EPIC Phase 3 clinical trial in pediatric patients with KCNQ2-DEE, our team is striving towards study completion in the first half of 2023. Finally, we look forward to providing updates on any key milestones reached within our partnered programs with Neurocrine and Pacira BioSciences. In conclusion, I echo Ian’s comment that 2021 proved to be a transformative year for Xenon. And on behalf of the entire team, we’re energized and to continue this momentum. We look forward to keeping you up-to-date on our progress with multiple Phase 2 and Phase 3 clinical trials anticipated this year and in particular, our advancements in our XEN1101 program. I’ll now ask the operator to open the line for any questions.

Operator

Thank you. [Operator Instructions] Our first question comes from Paul Matteis with Stifel.

A
Alex Thompson
Stifel

Hi, thanks for taking our question. This is Alex on for Paul. I was just hoping you could provide maybe a little bit more detail on sort of the hooks to patentability for your new patents for 1101 related to food effect and polymorph. Maybe walk through some of the key features there and maybe some precedent related to preventing infringement from these patents? Thanks.

I
Ian Mortimer
President and Chief Executive Officer

Thanks, Alex. Happy to answer that question. So yes, as you mentioned, and we’ve had – we’ve talked about this on previous calls. We’ve had some good success on the patent front in 2021, and we had U.S. issued patents and claims on both food effect and polymorph, the two that you referenced. So on the food effect, this was something that wasn’t anticipated early in development, but XEN1101 clearly does have a food effect. It’s multifold on Cmax and AUC. And so it was something that we had filed and now all of the efficacy data that we’ve generated for 1101 to date, so the X-TOLE study was taken the drug, the one pill once a day was taken in the evening in proximity with the evening meal. And so we expect that that to be continued development as we move forward, and that would be something on label. And now we’ve got IP covering that. And then on the polymorph side, so the – over the last number of years, we’ve done extensive polymorph screening to elucidate the number of polymorphs of the drug and to file on that and that covers obviously, the form that’s in development and will be approved. And so we now have issued claims covering the composition of polymorph as well for XEN1101. So these two sets of kind of new intellectual property that have been granted over the past number of months, it was in the summer and fall of 2021, would take the exclusivity for XEN1101 out to 2039, 2040, absent any extensions of term from that point.

A
Alex Thompson
Stifel

Great. Thanks.

Operator

Our next question comes from Brian Abrahams with RBC Capital Markets.

U
Unidentified Analyst

Alright, thanks. This is Lynn [ph] on for Brian. I know you guys get a lot of questions on which doses you’re going to take forward, though. I’d actually like to stay with that for just a minute. And I guess my question is, would you consider taking a dose that you haven’t explicitly tested in the Phase 2 forward, but one that’s intermediate, which is the 15-milligram dose? And it sounds like you’ve got some of that exposure mapping work in hand now. So I’m kind of curious, what are the final considerations that you’re sort of working through before you decide on committing a dose? And when you meet with the FDA, are you going to have the two doses that you’re thinking of in that meeting or are you sort of going to shape that based on their feedback as well? Thanks.

I
Ian Mortimer
President and Chief Executive Officer

Thanks, Leo. Good question. Chris Kenny, maybe I’ll make a couple of high-level comments and then you can dig in a little bit deeper. Obviously, we haven’t yet publicly talked about the doses that we anticipate taking forward. But as you mentioned, we have done a lot of work, including some detailed PK/PD modeling. The expectation is to take two doses into Phase 3. So the Phase 3 studies would have two active doses and placebo. But I’ll Chris go into greater detail as he kind of thinks about the dose range. Obviously, we studied three doses in the Phase 2 program. But Chris and his team have done a lot of work on thinking on dose selection for Phase 3.

C
Chris Kenney
Chief Medical Officer

Yes. Thanks, Ian. I mean the bottom line is that we’re going to come out publicly with exactly what the plan is once it’s been vetted by FDA. We have a very good idea of what we want to do, but we just want to go through that step before bringing it out to the public. I mean if you take a look at the Phase 2 data, you could make an argument that really anything between 10 milligrams and 25 milligrams could be brought forward into Phase 3. If you take a look at the – I mean, in terms of the factors that will weigh in on that, Ian and his presentation talked about PK/PD modeling. Obviously, that’s part of the picture. And then also the heavier weight is being put on sort of safety and efficacy from the actual Phase 2 data. So as I’ve said before, I mean, I think we’re in a pretty good – we’re in a luxury situation where any of those doses could be brought forward into Phase 3, anything between 10 and 25 milligrams. So we will be – I appreciate the enthusiasm. We’re going to be happy to go public with everything once it’s been vetted by the agency.

I
Ian Mortimer
President and Chief Executive Officer

Operator, if we can go to the next question.

Operator

Yes, sir. Our next question is from Andrew Tsai with Jeffries.

A
Andrew Tsai
Jefferies

Okay. Thanks and good afternoon. So obviously, you’re meeting with the FDA in Q2 and you’ve kind of outlined your kind of base case scenario as it relates to the Phase 3 next steps. But I’m curious in this upcoming FDA meeting, do you guys have an upside scenario in terms of the outcome if there is one or even a downsized scenario, anything that you can share? Thanks.

I
Ian Mortimer
President and Chief Executive Officer

Thanks, Andrew. Yes, I’ll provide some comments and Chris Kenny, you should provide your perspective as well. We’ve talked often with investors that there is a lot of things that we need to have a discussion with the FDA and make sure that we’re aligned. But I don’t think there is any kind of big binary questions that we’re going in with. Chris talked about it in his prepared remarks that we think we have good arguments that X-TOLE may be considered a pivotal study. So we will have that conversation. But our base case is that we’re running 2 Phase 3 clinical trials, regardless. So although lots to talk about, I’m not sure we really go into it, Andrew, thinking about kind of a base case or an upside case. We’re really planning for the Phase 3 program that we think is appropriate for the drug and what’s going to be required to get the drug approved and what the NDA package will look like. Chris, do you want to add to that?

C
Chris Kenney
Chief Medical Officer

Yes. I mean I think that what Ian said just now is a reflection that we have no intention of cutting any corners. We want to develop the drug properly so that it has a really good chance of being approved within – as quickly as possible. So I don’t think that there is anything that’s particularly challenging about that interaction. We do – getting X-TOLE to be considered pivotal will provide some optionality. So I guess if I were to pick an upside, I would choose that. But either way, we’re going to be doing two additional studies.

A
Andrew Tsai
Jefferies

Thanks. And a follow-up on the MDD program, depression program, that you filed an IND. It’s more of a kind of a high-level question is just that ezogabine, the predecessor drug, approved for epilepsy, that has shown benefits signals in open label as well as placebo-controlled study for MDD. And now that we know from X-TOLE that 1101 is indeed more potent and more efficacious in epilepsy, shouldn’t that – could that be the same case in MDD basically? Thanks.

I
Ian Mortimer
President and Chief Executive Officer

Chris, do you want to answer that?

C
Chris Kenney
Chief Medical Officer

Yes, sure. I mean, I don’t – I mean we’re obviously enthusiastic about this path, because we have an investigator-initiated study ongoing and then even a larger sponsor-initiated trial. The enthusiasm comes in terms of the mechanism being interesting in MDD in and of itself. And then in particular, as it may relate to patients with epilepsy who have mood dysfunction, you look at the data, you have preclinical data that suggests that the drug should be active in depressive models. And then you have the ezogabine story and the bridges you already pointed out between efficacy in MDD and FOS and then our focal onset seizure data. So I think that the chance of success might be better than the typical POC, but who knows? You never know until you’re at the end of the day.

A
Andrew Tsai
Jefferies

Thanks.

Operator

Thank you. Our next question comes from Marc Goodman with SVB Leerink.

M
Madhu Yennawar
SVB Leerink

Hi, thanks. This is Madhu on for Marc. Just a couple of quick ones from us today, you mentioned previously that you’re expecting a more formal cut of the X-TOLE open-label extension data sometime before your Phase 2 – end of Phase 2 meeting with the FDA. Could we expect to see that data sometime in the next few months still? And then secondly, just wondering if the Biohaven announcement caused you to rethink or revisit any part of your development plan for XEN1101? Thanks.

I
Ian Mortimer
President and Chief Executive Officer

Yes. Thanks for the questions. On the X-TOLE open label data, yes, we have looked at some of that data as it relates to, as you mentioned, to the end of Phase 2 meeting. That’s really focused on the safety aspects of that data, and we haven’t done any analysis of efficacy, but that’s kind of on our list of things that we will continue to get at. So no current plans, meaning, we haven’t submitted an abstract to any medical or scientific meetings in terms of providing any of the X-TOLE OLE data. But I do think that that will be something that will absolutely submit and share at the appropriate meeting in the future, so we can look forward to that. On the Biohaven announcement, we had a couple of comments earlier just because we’ve received a number of questions on Friday and over the weekend and yesterday. But no, it doesn’t change anything in terms of our plans. We’re very comfortable in the profile of 1101. And obviously, we’re significantly ahead. There is no other Kv modulator activator in development in clinical studies right now. So nothing has changed on our side and our focus to move 1101 into the Phase 3 program and generate data in MDD as well.

M
Madhu Yennawar
SVB Leerink

Thanks.

Operator

Our next question comes from Yatin Suneja with Guggenheim Partners. Please go ahead.

Y
Yatin Suneja
Guggenheim Partners

Hey, guys. Two quick ones for me. Did you speak about the size of the Phase 3 studies? I apologize if I missed it. And also, what would be the time point of an endpoint. It will be 8 weeks and 12-week? I have a follow-up.

I
Ian Mortimer
President and Chief Executive Officer

Sure. Chris, do you want to answer those two quick ones?

C
Chris Kenney
Chief Medical Officer

Yes, sure. I mean we haven’t gone public with the details, but the spirit of our Phase 3 studies will be as follows, X-TOLE worked. The data was robust. There was a nice separation between active and placebo. So, if it’s working, there is no need to fix it. So, as we go forward into Phase 3, we are going to only bring forward two doses. Ian has already said that. So, that will be one difference. But in terms of the general size of the study, number of sites, etcetera, try to keep it as similar, we don’t want to deviate from the plan that already worked. The other exception in terms of a change has to do outside of going from three doses to two. The other exception is that the duration of the double-blind period will be 12 weeks as you have pointed out, for both Phase 3 studies.

Y
Yatin Suneja
Guggenheim Partners

Got it. And are you waiting for EMA feedback given that the European requires a little bit of a different endpoint before you initiate the studies?

C
Chris Kenney
Chief Medical Officer

Ian, I am not sure it was public on that. So, I think maybe you should fill that.

I
Ian Mortimer
President and Chief Executive Officer

Yes. So often, as we know, European regulators are focusing on the responder analysis. So again, we haven’t gone through all the detailed Phase 3 protocol synopsis, but we will be looking at MPC and RR50 as we did in X-TOLE. So, we will have all of that data. I wouldn’t say Yatin, that the scientific advice is gating to getting the Phase 3 trial up and running, but it will follow with not a lot of time after the end of Phase 2 meeting. And then the Phase 3 program, as we said, we would like to be up and running and initiated the Phase 3 trial within the second half of the year.

Y
Yatin Suneja
Guggenheim Partners

Okay. Just final question for me. So, assuming you will initiate these studies in the second half, is X-TOLE a good proxy of the timeline within which you can complete these studies? Maybe just tell us how long it might take for you to run these studies?

I
Ian Mortimer
President and Chief Executive Officer

Yes. I think X-TOLE is probably a reasonable proxy, kind of a couple of things that people may wanted to take into consideration as they think about the timeline is – so from a sizing point of view, as we have talked about, there is probably not a big difference between the Phase 3 trial and X-TOLEs. We compare that, and Chris has mentioned, both in terms of the size, but number of sites as well. Obviously, the challenge we had for those that have followed the company for some time is we did have a COVID impact on recruiting and screening of patients during X-TOLE and obviously, we can’t predict the future, but it’s definitely the second part of the study of X-TOLE recruited much better than those months in 2020 early on in the pandemic. And obviously, we now have clinical efficacy. So, we have an opportunity to talk to investigators about that. But yes, overall, it’s probably not a bad proxy because it is a similar size study to the X-TOLE trial.

Y
Yatin Suneja
Guggenheim Partners

Very good. Thanks Ian.

I
Ian Mortimer
President and Chief Executive Officer

Thank you.

Operator

Thank you. Your next question comes from Tim Lugo with William Blair.

U
Unidentified Analyst

Hi. This is Lachlan on for Tim. Thanks for taking the questions. So we had a couple of questions just about somnolence and X-TOLE. So, can you maybe just remind us sort of what you saw there and what is, I guess typical or standard with other antiseizure medications? And then on the partnered programs with Neurocrine, are you able to provide any more sort of granularity on when in 2023, that data might come or how enrollment is going?

I
Ian Mortimer
President and Chief Executive Officer

Thanks, Lachlan. I will answer – Chris Von Seggern, I will answer the question on the partner on Neurocrine, and then you want to address the question on somnolence?

C
Chris Von Seggern
Chief Commercial Officer

Sure.

I
Ian Mortimer
President and Chief Executive Officer

So, on the partnered programs, yes, we are really – Lachlan, we are really guided by the guidance that Neurocrine provides. They are, just to be clear, I know we have talked about it previously, they are running the program and paying for the program and are in control of it. Two Phase 2 trials are up and running. The only one they have given guidance on is the adult focal epilepsy study that they expect to have data in 2023. They haven’t narrowed the guidance more than just during the calendar year. But that study is up and running and recruiting. And then in the pediatric epilepsy, that is also running and recruiting, but they haven’t given guidance on when they would expect top line data. So, as they narrow that guidance going forward, then we can update you there. Chris, pass it to you on somnolence.

C
Chris Von Seggern
Chief Commercial Officer

Yes. I was trying to look at the exact number because I don’t want to misquote it. But I mean the more common adverse event was dizziness and I just don’t want to quote what the number was with somnolence. There was a little bit of an imbalance in terms of active versus placebo. I believe it was hovering under 10%. And there was a bit of a dose response as there was with dizziness. In terms of its comparison to other ASMs, we thought that it was very much in line with other anti-seizure medications.

I
Ian Mortimer
President and Chief Executive Officer

Yes. And Chris, I was just looking at the AE tables as well. And yes, somnolence, actually, overall was about 15%. So, it was less – quite a bit less than dizziness. And actually, we saw about that same level of somnolence in the high-dose group of 25 milligrams at approximately 15%.

U
Unidentified Analyst

Okay. Thanks.

Operator

And your next question comes from David Hoang with SMBC.

D
David Hoang
SMBC

Hi. Thanks for taking the question. So, I just had maybe a little bit of kind of a big picture question. The focal epilepsy landscape, it may change a bit near-term, I think UCBs Vimpat may lose exclusivity and go generic. And so 1101, there is still a bit of time before it potentially comes to market. But just given that landscape and that shift, how are you thinking about down the line, potentially positioning for the best commercial launch out of the gates?

I
Ian Mortimer
President and Chief Executive Officer

Thanks, David. I think that’s – yes, it’s a really important question on how 1101 could fit into the focal epilepsy landscape. Chris, once again can you jump in and provide your perspective?

C
Chris Kenney
Chief Medical Officer

Yes, absolutely. So, Vimpat is expected to lose exclusivity later this month. And correspondingly, we anticipate that product will move up in lines of therapy based on being one of multiple products that would be used in a generic environment before moving on to branded agents. It does leave behind a massive hole to fill from a commercial space. And when you think about the other available branded agents, none have nearly the reach that Vimpat does from a commercial standpoint. And when we think about the profile of XEN1101, it has a combination of safety and efficacy attributes that will make it very competitive for the add-on agent of choice within that first branded market, which is predominantly where Vimpat stands today. So, we view the loss of exclusivity of Vimpat as one that will shift the nature of the standard of care early lines of treatment, but actually create a significant opportunity from commercial products downstream, which is likely where will be used.

D
David Hoang
SMBC

Okay. Thanks so much.

I
Ian Mortimer
President and Chief Executive Officer

Thanks David.

Operator

Next question comes from Antonia Borovina with Bloom Burton.

A
Antonia Borovina
Bloom Burton

Hello. Thanks for taking my question. Most of mine have been asked already. So, maybe just a follow-up to the earlier commentary? Can you maybe speak to how XEN1101 would fit in the treatment landscape given its profile in the Kv7 mechanism in MDD? And then just briefly on your discovery programs, when can we expect you to announce some additional programs? And do you plan to stick to epilepsies, or would you focus on neurology more broadly?

I
Ian Mortimer
President and Chief Executive Officer

Thanks, Antonia. I will address the discovery one and then Chris Von Seggern, if you want to provide your perspective on the MDD market and the need and where a drug with a profile like 1101 could sit. I know it’s early days, but we can probably provide some high-level commentary. On the discovery portfolio, as many of you know, we have a very active drug discovery group and a number of targets that we are interested in. Antonia, I would say broadly, we are interested in neurology. We have had a focus on epilepsy. Some of you will have seen our data that we have presented at meetings on a target called Nav1.1 where we are looking at activators of that target that could be used in epilepsy indications such as Dravet Syndrome, and we have some very interesting preclinical data there. And obviously, we have a large Kv backup effort now where we have backup molecules that over the next couple of years will go into clinical development that could either give us a lot of options in the clinic either from an LCM point of view or looking at different therapeutic indications as well. And we have different ideas on how to interrogate the target as we move forward. So, we have a big effort there. And then there is a number of other targets that we like and we are working on that we just haven’t talked about publicly yet. So, I would say we have broad efforts pre-clinically, and you will see a number of molecules transition from our discovery portfolio into the clinic over the next few years. Chris, on MDD?

C
Chris Von Seggern
Chief Commercial Officer

Yes, absolutely. So, the MDD marketplace is as complex, if not more complex than the epilepsy space, but had some similarities in terms of the treatment paradigm. There are entrenched standard of care products that are used early lines of therapy, SSRIs, SNRIs that address a portion of the patient population, but leave a sizable percentage of patients who require additional efficacy either in an add-on adjunctive environment or is downstream monotherapy treatment. We envision the profile for XEN1101 to be quite competitive in later lines of therapy where patients often turn to products that have alternative mechanisms of action with equivalent or comparable efficacy profiles. And what you are looking for is a mechanistic approach that’s either complementary to the SSRIs, SMRIs or something that is an alternative for patients who require additional efficacy or have safety or tolerability issues with earlier lines of therapy. That is a patient population and one that is going to be increasingly competitive as additional products move forward.

A
Antonia Borovina
Bloom Burton

Thanks for the clarification.

Operator

Thank you. And with that, we end the Q&A session for today. I will turn the call back to Sherry Aulin for final remarks.

S
Sherry Aulin
Chief Financial Officer

On behalf of the Xenon team, thank you, everyone, for joining us on our 2021 financial results conference call.

Operator

And with that, ladies and gentlemen, we conclude today’s program. Thank you for your participation and you may now disconnect.