Conference Transcript - DNTH 2026-09-09

Sam Semenko, Analyst — Citi

Good afternoon. I'm Sam Semenko, one of the Senior Biotech Analysts here at Citi, and it is my pleasure to be hosting Dianthus at Citi's 2026 Biopharma Back to School Summit. I'm joined by Marina Garcio, CEO of Dianthus. Marina, welcome, and thank you so much for being here.

Marino Garcia, CEO

Thank you, Sam, and thank you to Citi for allowing us to be here today and for hosting this webinar.

Sam Semenko, Analyst — Citi

Absolutely. So why don't we just start maybe a little bit high level?

Marino Garcia, CEO

You made a ton of progress across your pipeline this year so lots of great updates that have come from you guys um and there's still a few catalysts outstanding before the end of the year could you just maybe recap and level set where the company stands today and what can we can expect you through the end of the year and and maybe over the next six-ish months sure so um thank you for that and again thanks for the opportunity to update everyone today so over the last 12 months uh with class we have had uh two big moments in our development of classic bar neuromuscular conditions we had the very positive phase two magic uh results and mycena gravis from september or exactly about a year ago uh this week and uh and then the cidp update the early uh interim responder analysis we announced in march and then the uh fulsome update on our first 40 patients and as part of the interim responder analysis in June. You know, from our perspective, clasipibar is now pretty much de-risked as a very potent neuromuscular therapy and antibody. So the next update is on the third indication. It's our phase two results with MNN, which we are expected to announce our top-line results in December of this year. That is a phase two study. Originally, it was slated to have 12 patients per arm. We've over-enrolled, which is great. It shows a lot of enthusiasm for the program in the MN community. So we'll have about 15 patients per arm. So relatively small phase two, mostly a safety study. That's the primary endpoint. Secondary endpoints are efficacy measures and mostly exploratory. So the expectations there is, again, we'll report out if we see anything new on safety, and I can tell you on a blinded basis to date, it looks very similar to MG, very similar to CIDP, so no new surprises. And of course, we're looking for just numerical trends. We're just looking for the numbers on the efficacy measure, the secondary FCM points to be moving in the right direction. And really, our goal is to get to a phase three start as fast as possible. Back in 2024, when we met with the FDA to discuss the MMM program, we would have liked to have been able to go straight into a phase three the way we did with CIDP because it is an SBLA. But at that point, the FDA really did not know what a phase three should look like. They didn't have any direction to give us in terms of what the primary endpoint should be. So it made sense to do a phase two. But obviously, like CIDP would have loved to have had a precedent and being able to go straight into phase three. So we'll move to as quickly as possible into phase three with MMM. And in terms of 212, our next program, our bifunctional fusion protein, that is in a phase one SAD study in healthy volunteers. We'll provide an update on that by the end of the year and provide some visibility on when we'll start the MAD portion of the phase one and what our plans are over the next 12 months. We'll do that by the end of this year and then recently we announced uh 312 uh that we are moving that into uh getting it phase one ready by the end of next year those are uh some of the big moments on class we will provide another update on cidp uh that'll be before the end of the year just provide uh guidance on when to expect top line results for the Phase 3 Captivate study. We'll also provide an update on what we truly think the end will look like in Part A. Remember, the goal of the study is to recruit 128 patients into Part B, and those are patients who will have responded on Part A. Right now, we're saying we need up to 256 patients in Part A to get to that 128 in Part B. but if our responder rates look consistent with what we updated earlier this year, and to date they do look consistent, they're staying fairly consistent, if those responder rates continue to remain consistent throughout the end of the year, then we won't need anywhere close to 200 patients, even in Part A. So I'll provide a bit of an update on that, and that should be an important catalyst.

Sam Semenko, Analyst — Citi

And on MG, we've just initiated the eMERGE study where we're studying two different doses, once every two weeks and once every four weeks, and uh we're screening patients and that's all on track and we expect results from mg um top line results from that phase three study in the second half of 2028 thank you for that you it's a lot to dive into um i i think i'm going to choose to start in mg because that's where you ended um so i mean the phase two data that you presented is competitive um you have clean safety being a dosing presentation and regimen it's i think easy to see how you were a best in class complement inhibitor but also more broadly just across the

Marino Garcia, CEO

gmg landscape you know where do you see it fitting in like what seconds of the market does classy pre-bred have the opportunity to take meaningful share yeah and i'll just i'll just have one element that you didn't mention in the market research we're doing with neurologists one thing that came back very early on with some of the first neurologists we spoke to when we were presented data to him, is you guys should emphasize how fast this works. I mean, the stat-sig separation on QMG and MG-ADL within seven days is also really impressive and important for MG patients and neurologists and a key differentiator.

Sam Semenko, Analyst — Citi

Excuse me.

Marino Garcia, CEO

So in terms of what we expect, I mean, if you can imagine, you know, the MG landscape when claciprobar is available. You'll have FCRNs and different versions of FCRNs available. You'll have Oplizna and maybe you'll have BAF April. We'll see what the data looks like from VOR and Vertex, etc. And then you'll have the complement class, which has been the class that's, it's a foundational class in MG. It's been there forever and it's still being used first line. Obviously, The F-car-tigumab has done a really good job of getting first-line use, and C5s are being moved more and more to second-line. But within the complement class, you'll have all sorts of different C5 inhibitors and only one C1S inhibitor, only one pure classical pathway inhibitor that won't have any box warning or REMS program, and that will be potentially a once-a-month sub-Q auto-injector, like Dupixin. if you can imagine a label for a product like clacipibar where you just take the safety and tolerability from engymosetimumab which is approved in the u.s for cold agglutinin disease just cut and paste that safety label put it on ours and then go to the dosing administration for dupixent but make it once a month the exact same auto injector that's what we're going to be launching with put that into our label and an efficacy that's at least as good as c5's potentially better uh and works within the first week literally after your first dose you see efficacy you you should respond if you do respond um i think if we price that intelligently and competitively that should get a pretty nice share first line use and then in terms of second line i mean if if someone started on an fcrn the database the claims database if you look at in the U.S. right now, at least 40% of patients are not on therapy 12 months later. Clearly, F-serins don't work for everybody. Clearly, some patients are not going to be tolerating it or not enjoying the dosing administration challenges with a high-volume therapy. I think the next logical step would be something like clasipopartin. And so I see it as being a major blockbuster, getting a fair share of first-line use, certainly getting a good chunk of second line use and uh and that easily with a large market like mg in the united states where less than 20 percent of patients right now are in biologics if you think about a healthier younger uh more active patient with a busy lifestyle traveling who wants something super easy they can just travel with it keep it at room temperature in their bag and dose it to them give it to themselves wherever they are around the world when it's time to take their shot, I think Classy Prubart will be a very, very successful product in MG.

Sam Semenko, Analyst — Citi

And you've talked about this with me, and I have my own survey data to back this up, that neurologists do want to use new therapies that get approved here. And sometimes as first-line therapies ahead of FCRNs, sometimes after FCRNs, it's a bit of a mix. But I do see Classy Prubart fitting into that as well. And maybe you could talk to some of your market research. that you do?

Marino Garcia, CEO

Yeah, I mean, our market research shows that if you have something where you can say, look, it's an auto-injector, you keep it in the fridge. And if you need to travel and you're not going to be home when your next dose is up in the next month, take it out, probably be able to keep it at room temperature up to four weeks. You can literally give it to yourself anywhere. It's an auto-injector. Go to the Depixent website. Watch the patient video. It is amazing how easy it is. You don't see the needle. It's a 27-gauge needle it'll be very easy to self-administer literally takes five to seven seconds for the dose to be given and you're done and we will have the stability data to show that you can keep it at room temperature up to four weeks outside of the fridge and travel with it so physicians tell us that if you have something like that no box warning no REMS program works really fast potentially better efficacy than c5 there is a potential here for an upstream inhibitor to show if we can control placebo response well in our phase three and we we think we know how to do that and keep it to a two-point improvement on the mjadl for the placebo arm there's a potential here we could show better efficacy because it is an upstream inhibitor versus c5s i mean something like that even if it is similar c5 efficacy just a safety advantage just a dosing administration look at oblizna i mean honestly it's a bit of a dirty drug cd19 it's not perfect takes quite a while months to see the efficacy you can but it's doing so well why because it's a new option and the only advantage it has is that it's an IV every six months it this market is hungry it should be 40 to 50 percent penetration of biologics it's not because there's no therapy that's ideal yet i think clasipibar gets very close to the ideal to really push that penetration of biologics in the mg market and you didn't mention this yet but you have a q4 weekly dosing regimen included in the phase three which could really even extend that dosing to just quarterly um which to your point about a blizna you know it has advantages right no so uh our dosing regimen in our phase three is once every two weeks and once every four weeks it'll be once every two weeks and cidp and mmn but in mg i think it'll be every four weeks i don't think we'll see a difference in efficacy between those two and the reason is there's more and more evidence showing that you do not have to shut down the classical pathway the way every two-week dosing does. That getting somewhere above 70%, 75% inhibition of the classical pathway is enough to maximize efficacy in MG. So if that's the case, we have a once-a-month drug. There's no question. And that data comes from some Disrans data, where they showed 75% inhibition, got them a fairly good improvement on the MG-ADL versus placebo. we have our own data from our open label extension that shows that pk levels that are half of what our dosing every two weeks would achieve still you have patients responding on on the drug significantly so really it doesn't look like you need to get above 90 on mg in mg patients in terms of inhibiting the classical pathway to maximize efficacy so we'll see but we're still testing every two weeks either way honestly this is a in terms of dosing administration the feedback

Sam Semenko, Analyst — Citi

from neurologists and patients says this is a winner it's infrequent it's easy no box warning no REMS program either way is it wins but of course if we can do it once a month instead of two weeks why not sure for sure um and then maybe if we switch gears to CIDP you know from a commercial standpoint I'd argue that there's even more white space in CIDP maybe it's a little bit easier to to penetrate the market uh for a new therapy to take share um but the market is smaller so i'm wondering just how we think about classiburotra fit into that treatment landscape since there are other complement inhibitors that are in development from argenics and sanofi sure well so sam if it's okay i might challenge a little bit on something you said which is

Marino Garcia, CEO

that maybe i um cidp uh there's more white space you know if you look at the cidp market historically IVIG is really well entrenched and if you've listened to Argenix over the years they've tried to really moderate expectations because IVIG is so well entrenched and it works in CIDP. I think the issue is if you have a treatment that is even more efficacious than IVIG better tolerated no box warning and self-administration sub-q like we are going then yes then this market will be wide open for a therapy like that fcrns are not as effective as ivig they're better tolerate they're more patient friendly so definitely a nice innovation for the space but in terms of efficacy there's nothing that can that comes close to ivig right now on the market our data suggests that inhibiting the classical pathway in a very potent way like we do with clasipibard may improve how patients are responding to standard care, including IVIG even further. That's what we're seeing in our Part A open label. Because of that, you know, the biggest opportunity in CIDP is converting patients from IVIG, is having them switch. And right now, if they switch to FCRN, I mean, there's a significant risk of relapse. What we're seeing in our Part A, which is an immediate switch from standard care, including IVIG. Three-quarters of patients are doing even better on clasipibri than they were doing on IVIG. That was information we didn't know before this year. That's clearly what we're seeing in Part A of our Captivate trial. In terms of what that means, well, CIDP, the value of CIDP for us, is definitely increasing because of that. and then on top of that when you look at what our competition for classical pathway inhibition is well first with lipid bar they now have terminated mobilize for futility so they'll have one negative placebo control trial and they have vitalized which uh suppose it was a positive futility analysis so that's moving forward so as far as i can tell they'll have one negative placebo control trial one positive placebo control trial possibly i'm not sure if you can follow bla with that i'm not sure what they're going to do if they believe like i do that you need a second placebo positive control trial that um to file your first bla that may mean they have to start another trial and that would definitely delay their introduction to the market and they would come after us so there's a strong chance here that relipobar doesn't even make it to market but if they do that's fine they are four times more injections than us and let's assume everything else is equal, although we'll probably have good data on refractive patients, and they won't have that because of ending the mobilized trial. And then there's M-pacipabart. We'll get further updates, I'm assuming, on their progress later this year, but M-pacipabart is, of the three, Rilpabart, us, and M-pacipabart, of the three, it is the weakest of the classical pathway inhibitors. Does that matter? I'm not sure. But I know for sure they blocked the lectin pathway as well as the classical pathway. That means they're going to have a box warning. There's no other way for your complement system to respond to the presence of encapsulated bacteria. If you block both lectin and your classical pathway, there's no way for them to initiate the cascade, trigger the alternative pathway to rev up and create more MAC to go and lice the bacterial infection. So they'll have a box warning, and they're in IV. So in the end, if they do get approved for CIDP, there'll be another option, obviously, but that one will have a safety disadvantage and certainly a dosing administration disadvantage. And that's assuming efficacy is equal. But again, if potency matters in CIDP, we should have better efficacy as well. So that's it. there's really nothing else right now that i see coming into the cidp market so for us we're very very focused on getting to the best level possible there of course and a positive outcome with captivate our phase three trial and then the strategy will be very focused on going after the ivig patient population if you talk to patients who have cidp on ivig who are stable and doing well they'll tell you they they thank they thank god for cidp uh sorry for cip i apologize for ivig it saved their life but boy would they love to be able to get on something else and even if it's just similar in efficacy if you come to the market with something that looks like it might do might be even better and better tolerate no box warning and self-administration sub-q self-administration that's a game changer and one last point the largest patient population we are recruiting and to Captivate are patients who are stable on standard care, including IVIG. Think about that. These are patients who are supposedly doing fine, and they're on IVIG. Why would they risk going into a trial and changing their therapy? It's because they're looking for something that's equal or better on efficacy, but just much better tolerability and much easier to take. And that is really the huge unmet need in CIDP.

Sam Semenko, Analyst — Citi

When you talk to physicians sometimes, though, to your point, IBIG is very entrenched. I guess, you know, what do you think physicians want to see in order to change that treatment paradigm? And also, particularly, IBIG is still used as a diagnostic for CIDP.

Marino Garcia, CEO

I mean, is there a first-line opportunity down the road once you have, you know, physicians have more experience, or it's just in the beginning that you're really focused on that switching market yeah i mean when i say switching uh focus that i'm just saying that's the largest opportunity because there's a huge amount of patients who have been diagnosed and on ivig uh of course positioning it as a good first line therapy will be the ideal position to take i mean in naive patients in our trial we're seeing near 100 response rates on the early you know patients that we've seen in part a look when we have the results from captivate i think what physicians are going to be very interested in seeing is what happened when you just switch patients within seven days there's no washout there's no making patients relapse like you saw in that here try on captivate we literally take a patient who's on standard care or IVIG within seven days just switch them what happens and if you see very little relapse rates if you see you know maybe another chunk of patients who stay stable but they're now on a much better tolerate easier to take drug but if you're seeing like what we saw in our first 40 patients close to three quarters of patients doing better improving I mean that's how we were defined a responder in part eight these are patients who are being switched immediately and doing better i mean and and if you look at our slide deck and our corporate deck it's not just one point improvement on the incat i mean it's every measure consistent across very robust response rates uh physicians are going to be very comforted by that and then if on top of that again you are able to not have a box warning no rams program and it's a auto injector the patient can give themselves anywhere they are around the world every two weeks like a dupixin i mean i think that's as long as we don't do anything crazy on pricing and if if we are going to be more expensive than ivig so do i expect some payers to maybe say you have to try ivig first sure but can you imagine what you know what neurologists and patients are going to do okay we're going to try ivig payers tell us we have to do this if you can't tolerate it though then we can try something else i mean no patient's going to come back say i love this this is great i tolerate really well i'd love the dosing administration that's not going to happen with ivig so uh i you know there's just a huge opportunity so for us the idp i mean i think it's very fair to say it's become an even bigger opportunity now than mg was and mg was always a huge blockbuster opportunity for us in my defense that's what i meant by more white space i mean it's uh it's it's you know if you can show that you are switching patients off of standard care and they're getting better in a

Sam Semenko, Analyst — Citi

very robust manner very quickly I think that's uh that's a game changer in CIDP for sure and so we look forward to that update that you're going to share at the end of the end of the year for timing yeah well I'll try to be patient um I do want to spend a little bit of time on MMM since it is your next data catalyst you gave us a little bit of a preview on on what to expense expect there you know it's a safety trial you're looking for trends um but you know is there is there a threshold if everything moves in the same direction is that enough to convince you to to move to phase three and you know maybe complicating or helping we'll see you're also getting you know our genix's mmn data around the same time so how should we you know in the investment community

Marino Garcia, CEO

really think about positioning as we as we move into that how should we like frame our expectations i think is a better way to say it sure look um i don't want to sound overly confident or flipping here there's almost nothing that we can see in phase two that will convince us not to go into phase three we know mmn is igem driven that's triggering the classical pathway we know mmn is a classical pathway driven disease we know dosing every three every two weeks with 300 milligrams we are getting very potent inhibition of the classical pathway there's almost nothing that we're going to see this prevent it going to prevent us from going into phase three literally again phase two was this phase two trial was a safety trial study primarily we're not seeing anything new no surprise um we expect to see some numerical changes on the secondary um endpoints the efficacy endpoints none of them we don't expect any stat sig the numbers are too small just like with empa their study was a little bit larger actually their phase two with empa and they didn't see any stat sig um that's it we're just going to move to phase three as fast as possible the key is what can we learn from our genics as phase three my hope is that they show non-inferiority to ibig and that their study was a success and that the primary endpoint should be grip strength and so then we will just replicate what they've done go to the fda get agreement and start to study as fast as possible if they show non-inferiority but not superiority that leaves the door open if an mmn you can get better efficacy by being a more potent classical pathway inhibitor then it leaves the door open for us to potentially show superiority if they show superiority versus ivig that's fantastic that shows that even not being a very potent classical pathway inhibitor is enough to show that you're better than ivig and mmn and And IVIG is not great in the amendment, but it is approved. So that would be a really great development for patients and certainly should give investors comfort that we will show the same because we are a more potent classical pathway inhibitor. Now, there is a scenario where somehow they don't show that they're even non-inferior if they have a failed study. If that's the case, I would just remind investors, we had the same situation with Relipibart and Sanofi in June with Mobilize. and after a couple of days of intensive discussions with investors i think people were reassured that they have to remember we have a very potent classical path maneuver more potent than relipibard and even more potent than empa sipibard we're seven times more potent than relipibard at the ic90 on the ch50 malic assay we are 38 times more potent uh than empa sipibard in the head-to-head comparison we have in our slide deck using the same assay that Argenix used to demonstrate their potency in their publication. So if they somehow just did not shut down the classical pathway enough, I remind people 300 milligrams every two weeks, we get over 90% inhibition. That is really shutting down the classical pathway. We will see efficacy. So I just, I can't really imagine right now why we would not go into phase three, even if a placebo-barge study is a fail because we do have a different classical pathway inhibitor, a much more potent classical pathway inhibitor. So I hope they're successful. They'll be reassuring for everybody. Patients will benefit from that, and then we can come in with, I think, a better profile once we get approved, assuming we get approved, of course.

Sam Semenko, Analyst — Citi

Looking forward to seeing the data from your trial as well as Argenix is done. Well, something to look forward to. So I do want to leave a little bit of time to talk about your early stage pipeline, 212 and 312. They're both very interesting assets. And for 212, you've prioritized SLE, Sjogren's, and dermatomyositis. Once we get the data later this year for the Healthy Volunteer Study, how should we think about how you're going to prioritize and, you know, go about the path of developing 212?

Marino Garcia, CEO

So to be clear, what we're going to provide by the end of this year is just an update on how the SAD portion, the single-dose portion of our Healthy Volunteer Phase I study is going, and then provide visibility into 2027, when are we going to start the MAD portion, and then our thinking around the three indications and when those studies will start. So that's going to be the update later this year. um i still believe and we still are planning for sle to be the first indication we go after because that's where the highest probability of success is and we'll have another de-risking moment from our competitors will be biogen's phase three data and sle with litafil map which is their bdca2 uh therapy and uh you know we look like we're more potent in terms of pdc depletion um we're hoping they'll have stat sig and be a positive uh outcome and and show separation from placebo and then again that should reassure folks that 212 should have at least similar efficacy probably better because it has the bath april side so later this uh yeah later this year we'll provide an update on how um the single dose portion of the phase one healthy volunteer study in china is going and uh and provide more of an update on when we'll start the mad studies and when to expect, uh, or the MAD cohorts, I should say, and then when to expect data from that as well.

Sam Semenko, Analyst — Citi

And the MAD cohorts are going to be also in healthy volunteers? Yes.

Marino Garcia, CEO

And, uh, if we are looking to do any part of the phase one in, in, uh, patients, we'll also provide an update on that.

Sam Semenko, Analyst — Citi

Got it. Understood. And then, you know, you, you also mentioned you recently unveiled 312, which is, um, you know, I guess next generation classy prubart, if I may, um, the c1s in the back of april dual inhibitor very interesting like life cycle management for classy prubart also allows you to expand beyond classy prubart can you just talk about your vision for how you're thinking about developing this molecule as well yeah i mean uh i'm really excited about that one uh because obviously it builds on our experience now we have with classic prubart we know classic prubart inside out um and um you know the idea here is if you can imagine by the time our clinical development clinical operations regulatory everybody's done

Marino Garcia, CEO

with developing one class hyperbar and handing it off to the commercial organization to go launch we have all this expertise all these relationships all these um insights we've learned from developing developing class hyperbar and mg cidp and mmn and all of a sudden we give that same organization 312 which is essentially a a more powerful version a more um you know potentially more effective version uh than class hyperbar or any bath april and certainly the three neuromuscular conditions so the idea here is to take that all x all that expertise all those lessons learned all those relationships kols investigators all that knowledge and then apply it and move as quickly as possible with 312 and then um you know there's definitely more indications we can go into with 312 because of the bath april side as well as the active c1s inhibition side and those indications will determine at some point in the near future but definitely starting with cidp mmn and uh and like i said mg um it has a longer patent life and you can just imagine the kind of uh franchise we could build and in the neuromuscular field and that expertise that we're building with class hippobart and and then we'll have built with commercial by the time 312 also launches it's really exciting and with the extended IP and the extensions will probably get to that IP I mean we could be in this near muscular field into the 2050s with this franchise it's really really exciting Yeah, looking forward to seeing that one progress over time.

Sam Semenko, Analyst — Citi

So we are at time, but I wanted to give you maybe an opportunity to share any closing remarks that you had, maybe recap the runway, cash runway for us. And I think you've done a great job at outlining the catalyst, but if you want to emphasize that as well.

Marino Garcia, CEO

Sure. So, look, for Clasipibart, it's our Phase II MMN data in December, as well as our GenX is Phase III MMN data with M-Pasipibart in the fourth quarter. With 2-on-2, it's our healthy volunteer update, and Biogen's Lidafilumab update on their SLE Phase III study with their BDCA2. on CIDP I think that'll be an important catalyst we'll provide an update on on class hyperbar and how when to expect that phase three study to read out and and how we're seeing the end that we need in part a in order to get to 128 patients in part b how we see that evolving and like I said if the current trends continue then we are not even going to need 200 patients in part a to get to that 128 patients in part b um we have a one point we have 1.2 billion dollars uh in the bank that takes us into 2030 so we have plenty of cash to execute on all three programs like and all the different indications and and read out all the important catalysts in the next few years uh that gives us just a lot of optionality and uh the team's doing a great job and uh we're feeling i'm feeling really really pumped, really excited. And I can't wait. I could see 2.1.2 and 3.1.2 adding even more value to the company and for shareholders over the next few years than Klessypibart has to date. So I feel like we're just getting started.

Sam Semenko, Analyst — Citi

Yeah, lots to look forward to. Well, thank you so much for the time. This has been wonderful. And I really appreciate you being here, Marina.

Marino Garcia, CEO

Thank you, Sam. I really appreciate it.