Dianthus Therapeutics, Inc. Common Stock 12th Annual Cantor Fitzgerald Global Healthcare Conference

What happened? That's a great way to start.

Thank you. Let me just start by saying thank you, Pete, for hosting us and doing this seminar or this webinar this morning. Look, it's been just a tremendous last 12 months. I'll start just by giving a quick overview on claseprubart, our lead program. It's a very potent, active C1s inhibitor with a YTE half-life extension. 12 months ago, actually, around this week, we announced the top-line results from our phase II myasthenia gravis trial, and frankly, the data was much better than expected. We had statistically significant improvement within the first week on both the MG-ADL and the QMG, and that statistical significance was maintained through the end of the study to 13 weeks. That was a big first pivotal moment for us.

Earlier this year, we read out the results from our interim responder analysis for our CIDP phase III study. That also beat expectations, both our own expectations as well as I think investors'. From our perspective, claseprubart, we now see it as a de-risked, very potent, very effective neuromuscular therapy. What's next for claseprubart? We have our third indication, MMN, and it's a small exploratory phase II study that we will read out in the month of December this year. We had initially planned for 12 patients per arm. We're testing two doses as well as placebo, of course. It was initially aiming for about 12 patients per arm. But we announced we over-enrolled. There was a really good enthusiasm out there for claseprubart and MMN. So we have about 15 patients per arm. It's primarily a safety study.

That really is what it was designed for. I can tell you on a blinded basis, the data looks exactly the same as MG and CIDP. Very clean. So no surprises. All the efficacy measures, including grip strength, which now looks like may be the primary endpoint in a phase III study. If you look at argenx's MMN phase III study with empasiprubart, their C2 inhibitor, grip strength is now the primary endpoint. So grip strength and the other muscle strength measures are all secondary and really exploratory. What should investors expect? We're looking for trends. We're just looking for the numbers to be moving in the right direction. There should not be any statistical significance versus placebo. It's a very small study, so very similar to the phase II that argenx had for empasiprubart and MMN.

The other big milestone coming up for claseprubart is we will provide further updates on our CIDP program. What I will be able to update investors on is when to expect the top-line results for the whole trial, for Part B, the blinded randomized withdrawal portion of the trial. When exactly will we be done with this phase III trial? Also give a little bit of direction in terms of what N do we really think we need in Part A of this phase III study. Just a reminder that only people who respond to claseprubart above and beyond where they come in at baseline, for example, on standard care of IVIG, only patients who do better on claseprubart 300 milligrams, 2 milliliters every two weeks, only those then get randomized to Part B. Right now we are saying up to 256 patients are required in Part A.

But honestly, if we see the current trend continue, the current trend being the efficacy or responder rates very consistent with what we announced earlier this year. If we see this current trend continue into the future, we will not need anywhere close to 256 patients. We may be able to get the study done even faster. We just recently announced that we started the phase III program for myasthenia gravis testing once every two weeks but also once every four weeks versus placebo. That is well on track, and we will have results for that phase III in the second half of 2028. Claseprubart is what is really driving this growth in our market cap based on your question. We have a very exciting pipeline behind it. I do not think that is really being appreciated just yet, but I understand they are fairly early.

Yeah. DNTH212, maybe we will get into that later, is still in its single-dose healthy volunteer phase I study being done in China.

We recently announced DNTH312, which is where we are taking claseprubart and combining it with BAFF/APRIL or TACI, and that will be phase I ready by the end of next year. But the team's execution and the data that has been delivered with claseprubart, I think, is what has really resulted in this nice appreciation in our market cap.

Yeah. It's great to watch from my side, too.

It's a great question. CAPTIVATE, our phase III trial, is a two-part trial, and it's really modeled on the ADHERE trial from argenx, which they conducted in CIDP and got them a very nice label for efgartigimod. It's a two-part trial. The first part is we confirm that patients have CIDP, multiple steps. The investigators have to confirm the patients have CIDP and it's active disease. We have an independent review board, panel of three different KOLs. Each one has to independently of each other in a blinded way look at every patient and decide and say, "Yes, this patient has CIDP, and it's active." And of course, we also have to agree. Those patients then come into our trial. They could be naive to standard care. They can be on standard care, including IVIG, or they could be refractory.

And what we saw in our first 40 patients, which we revealed earlier this year, is about 10% are naive, about a quarter are refractory, and two-thirds are standard care stable. What do we do? We take those patients, we take them off standard of care if they're on standard care, including IVIG, and we switch them right away to claseprubart, open label, 300 milligrams every two weeks. And only patients that do better, they have to improve, not stay stable, but improve further in a very clear, robust way, in a consistent way over two different visits after week 5. Only those then get randomized to the blinded randomized withdrawal portion of the trial, part B.