My name is Roger Song, one of the senior analysts cover small-cap biotech. It's my pleasure to have the next 30 minutes, the fireside chat with company Cabaletta Bio, and then we have Steven, CEO, and then Steve, Chief Commercial Officer here. Welcome, gentlemen.
Thank you.
Thanks for having us.
Awesome. What a great start because Cabaletta just put out the data from the fresh off the press, the EULAR across the pipeline. It's very impressive. We took a look. I think we can have a lot to talk, but before that, maybe, Steven, do you want to have a two-minute state of our for Cabaletta? Because I think a lot of people have been missing the big picture, but obviously, we're going to talk about all the trees.
Yeah. First, thanks for investing the time so early in the morning today. We are thrilled to finally be able to share a body of data, over 50 patients treated with rese-cel across five or six different autoimmune diseases, reflecting the fact that we've got a pipeline and a product. We have presented earlier today, both in a press release and an updated corporate slide deck, which reflects the essential findings that will be presented at EULAR over the next few days in terms of efficacy and safety of rese-cel in multiple indications. Some of the key findings in the press release include that in our phase I/II myositis study, over 80% of the patients who were treated in the phase I/II study would have met the primary endpoint of the ongoing phase III program.
The estimates are currently that no more than 50% of patients would need to be positive in that study in order to achieve a registrational filing that is successful. We really feel very comfortable with the design and with the data that we've now presented in myositis, and we're thrilled at the same time now, to be able to talk about the first patient with juvenile myositis, Juvenile Dermatomyositis, a problem that is currently affecting a couple of thousand children in the U.S. The first patient that we've treated was treated just like our adults in the sense that it is a weight-based treatment regimen. It's not easy to go into kids unless you know the dose, and unless you're doing a weight-based dosing, it's very difficult to figure out what dose to use.
We didn't need to do any dose finding. As a result, we are now moving forward with a Juvenile Dermatomyositis cohort. The first patient who responded, similar to the adults, a moderate to higher level response on the TIS score that is durable. In the adults, I failed to mention, we're seeing durability as long as 1.5 years. 100% of the patients who hit the primary endpoint in that phase I/II study have gone on to have durability throughout the entirety of their follow-up in every visit. It does look like dermatomyositis in adults, dermatomyositis in children, will be the basis for our filing of the BLA in the second half of 2027, which will open up a new opportunity for Cabaletta to potentially secure a PRV associated with the Juvenile Dermatomyositis filing.
We also announced that in scleroderma, we're seeing actual improvement in ILD, patient's lung function. The FVC is improving. That's not something that is possible with today's approved therapies, doing it with a safety profile that's quite attractive. Thrilled that that'll be moving into a registrational program with initiation of that trial later this year. Finally, among other things, we announced in the first two lupus patients treated with a PC-free regimen, no preconditioning at all. We basically said, you're on multiple medications. You're a refractory lupus patient or lupus nephritis. Come on in, and we'll give you a single infusion of rese-cel and nothing else. Oh, by the way, you're going to stop all of the medicines that are failing to control your disease today. The question is, will you improve over time?
In the first two patients, what we saw was that one of the two ended up having the sort of Pharmacokinetic and Pharmacodynamic response that we see in lupus patients treated with rese-cel plus preconditioning, who end up going on to have a reset of their immune system. We feel very excited, frankly, that at this lowest dose of rese-cel, because we'll test multiple doses going higher, the thesis has always been a higher dose of rese-cel is sufficient to replace preconditioning. At this lowest dose, we're getting one of those two patients looking like they're headed towards an immune reset with nothing but a single infusion of rese-cel. Overall, just really thrilled about the opportunities ahead of us.
Excellent summary. All right. Cabaletta Bio is in a very interesting setup front here. I understand the cell therapy for autoimmune and getting a lot of attention, and then later on, people realize that we still need to deliver the real therapy to patient as a real business model, the durability, payer, patient. I think Cabaletta Bio has tried to address all, most, if not all of them. Maybe today's conversation, Steven, you already give us the overview, but I think today conversation maybe we'll also focus on the EULAR data, and then we can save some time for the bigger picture toward the end, wrapping up. For the EULAR, so for the myositis, this is you're already in the pivotal. Data going to be mid-year next year, and the filing next year will potentially be the first approved cell therapy for myositis.
What is this data really telling people? What you're really excited about, particularly for the durability? Tell us, I know you have a detailed in a couple slides in updated corporate deck. Maybe just walk us through how long the follow-up you have been seeing and then how the durability look like, because that's one of the key thing for cell therapy.
Yeah. Let's focus on the business of treating autoimmune patients. To do that, you need to start with the data. I'm going to spend two minutes on the data, and then I want to pass it off to Steve Gavel, who's our Chief Commercial Officer. His experience is, I would say, somewhat relevant, having been at Celgene with Abecma and having launched CARVYKTI as the Lead Commercial Officer at Legend on CARVYKTI throughout the vast majority of its history, from inception through about a year and a half ago. The myositis as a target, it was chosen by Cabaletta. Some of you who have followed us for a long time will remember. It was always going to be our first lead indication. We felt that everybody would run after lupus and there would be just too much confusion, too many people going after the same patient.
Frankly, the data in myositis looked terrific. These are patients who a third of the time are using walkers and other walking assist devices. Patients who have really life-altering limitations due to their myositis. Although it's little recognized as an investment opportunity, the standard of care today includes only one approved therapy, and soon there'll be multiple other approved therapies. IVIG, come into the hospital for two or three afternoons this month and next month again, and we'll continue to give you your IVIG dosing to try to control your myositis. It's only indicated in the one indication that we are prioritizing dermatomyositis. Not only is it costly, but it's burdensome for the patient, for the hospital system, and frankly, it's not that effective.
Now imagine that you can simply replace that, and in over 80% of the patients who are treated, they're getting a reliable reset of their immune system. They're no longer patients. They're getting their lives back and not taking any other medicines. For us, it's thrilling. For the patients, it's got to be more thrilling. For the physicians, both the dermatologists and rheumatologists who are treating these patients, it's got to be thrilling. For the payers, they're no longer paying for anything for these patients. When we think about the opportunity and the value that's being created by rese-cel in patients with dermatomyositis, and I'm only speaking to the adults, the children end up with these calcium deposits, and if the calcium deposit is in their fingers, they're not learning to use their devices, and they're not able to use their devices.
They're not able to sit in class because of the pain or these calcium deposits, this calcinosis that occurs in these kids. We see the calcinosis in both the academic literature and we'll see how our own patients fare, but we see the calcinosis essentially disintegrate. It's really quite a remarkable one and done therapy that delivers very high value. The key question for payers, that we believe is going to drive the opportunity is can I avoid payment for future product, for future pharmaceutical product because I used one dose of rese-cel? We've been doing a lot of work on that and I want you to notice that we're not filing until the second half of next year.
We are well on our way to commercial preparations because we understand how hard this can be in cell therapy, and one by one, our safety profile and the value proposition are all being explored in great detail by Steve and his team. Let me turn it over to him to talk a bit about what we're doing to prepare for a successful launch of rese-cel.
Yeah, thanks, Steven. A number of things that are happening commercially for us right now. Steven talked about opportunity. One of the things that we're pretty deep in right now is a fair amount of market research with the payer community because the key question is what will the payers need to see in order for us to ensure payment? This is fundamentally different than what we were used to back in the days of launching cancer drugs. We see the majority of payment coming through Medicare. We want to test this out, and the payers have been very consistent. Prior to when I've come on board, and most recently, we concluded a fairly substantial market research study that we looked at socializing this product profile that you're starting to see in the data we're presenting today and are very clear.
They want to see at least 52 weeks of durability in terms of the response rate, as well as Steven mentioned, being off all therapies. What we're starting to see in the data that we're now obviously presenting here at EULAR or the most recent update, is we are starting to hit that mark, which is really encouraging for us. The other piece of it, so that speaks to the efficacy component, obviously, which is very, very important, obviously. The second piece, though, that really opens up and a bunch of opportunities that we could not open up in other programs that Steven referenced that I was managing before, is the toxicity profile. The tox profile with rese-cel is unprecedented for a CAR T product. Full stop. It just is.
What that's allowing us to do commercially is getting into areas from a go-to-market model that was basically a bridge too far for us with the programs that I was working on. Where I'm going with is, for example, our CRS profile. The overwhelming majority of patients, actually 94% of patients, don't even experience CRS. It's unheard of. What that allows in terms of the opportunity for providers and our hospitals is to finally be in a position where they can treat the majority of their patients in the outpatient setting. That's very important for us. The reason why that's so important for providers is because there are so many now inpatient cell therapies that they're dosing in the hospital. The majority, they just basically are resource constrained.
They're looking for options to provide to these patients that will give them the ability to receive these therapies in the outpatient clinics. Our go-to-market model is very different than what I've been used to in the past, where with my old program with CARVYKTI, we gradually over time migrated to the outpatient setting in the hospitals. Again, we were limited because of the toxicity of that program as well as how sick the patients are that we were treating with late-stage cancer. We don't have those rate limiters now for autoimmunity. We're very excited by that. The insurers are very excited by that because it actually starts to really reduce costs for these therapies. Providers are very happy because they're actually able to treat more patients.
Again, this is a key focus for us and will continue to be the focus as we do more and more research in this area.
Just to clarify one fact.
Yeah.
The 94% that Steve is referring to, in terms of our CRS risk or absence of it, two-thirds of all the patients have no CRS at all and no ICANS at all. In fact, there is no ICANS at all in our myositis program, zero. In terms of Grade 1 CRS, which I want to be clear, it's fever that's well managed and easily managed in all cases, in a matter of a two, three-day period at most. Then you're done. I want you to just take a moment to take yourself out of the world of CAR T and think about what are the side effects of rituximab chronic therapy? Is there a risk of hospitalization due to infections that rises to the level of real concern for patients and physicians? The answer is clearly, definitively, yes. The absence of B cells over time matters.
With rese-cel, we're talking about something between six and 12 weeks at most of absence of B cells. It's a transient Reset. The dose of rese-cel is achieving something that is really the holy grail, where with a transient, deep, reliable depletion of your B cells, you have the opportunity to no longer be a patient. That allows for us to focus on how to use that profile and, as Steve said, going into the outpatient setting and making the access for patients possible, and allowing hospitals and community infusion centers to then access or provide access to rese-cel in far more sites than one could think of in cancer. Those are the sorts of opportunities that we're excited about.
Excellent. It's truly a one-and-done therapy on both efficacy and safety. Yes, we may see some risk, but majority of people not even see that. After a certain period, you're back to a healthy state because your B cell can reconstitute, you're no longer immunocompromised anymore. It's not like a chronic dosing for most of the immunosuppression therapy for this type of the disease. Right. Two-pointed question for the data in terms of the durability. One is, I believe nobody lose response for the follow-up you have seen for the all the responders, moderate and then a major responder. No one lose response. Just let us know what's the range of the follow-up you have seen for this data set? Two is, maybe just quickly, just on the expectation.
From physician, maybe patient, and then payer, how do they expect to see the durability for those major response, and then what will consider to be a game changer?
I'll give you this, Steven.
Yeah. As shown in the slides that we posted in an 8-K this morning, our corporate slides, over 80% of patients achieve the primary endpoint at 16 weeks. 100% of those patients remain durable as long as 1.5 years into their follow-up, which is the longest follow-up we have available. Said differently, 100% of patients 100% of the time after they hit the primary endpoint maintain their response. We think that's pretty remarkable, but maybe even more notable is that 100% of patients who got rese-cel never took another drug in their myositis history. Even for patients who did not hit the primary endpoint at 16 weeks, they stopped all of their immunomodulators, and they never restarted them.
They had improved, but at week 16, as you'll see in the data, at week 16, they didn't happen to hit moderate or major TIS improvement. Literally, 100% of the patients who got a single dose of rese-cel never took another myositis drug in the trial. Let me pass off to Steve.
Yeah. Thank you for that question. It's an important question around threshold, right? This is what we are testing for, especially with the payer community. The minimal threshold that payers are requiring right now for payment is about 52 weeks, one year. They'd love to see about a year and a half. That's their preference, but their minimal threshold is right around a year and that correlates also with physicians.
Excellent. We are already getting there.
Exactly.
Already above a year.
That's right.
Some patients, they are getting towards because everyone at least six months for the primary endpoint.
That's right.
I believe the slides show majority of them moving towards one year.
That's right.
100%. Okay. Got it. All right. We do have a couple other data sets we want to just quickly go on. The [Pemphigus Vulgaris] side is because it's pivotal, we want to spend a bit more time. You just announced the second pivotal indication, which is scleroderma. Also you have some data there. More important is that you align with the FDA regarding the pivotal plan. Tell us about the data highlights and maybe the FDA. What's a key component for the pivotal?
Yeah, for clarity, in scleroderma, about 70% of all of the patients are going to have interstitial lung disease, and those are going to be the more severely affected patients who have fibrosis in their lungs as well as typically their skin. Others may have it in their heart and lungs or heart alone, organ systems in general. Interstitial lung disease is an area of severe impact in patients with scleroderma. What we see with rese-cel is, by the end of a year, actually 100% of the patients treated are achieving the revised the ACR- CRISS endpoint that is skin and more broadly oriented.
More objectively and more pointedly, we've agreed, based on conversations with FDA and conversations with our physicians, that the primary endpoint in our single-arm study with scleroderma patients will focus on interstitial lung disease patients who are the most severely affected, and we will focus on a very hard endpoint, the FVC, the Forced Vital Capacity, in those patients. For clarity, there are a couple of therapies approved for scleroderma. To give you a sense of how severe the unmet need is in scleroderma, these drugs are approved to slow the rate of decline. Remember, these patients have a 50% survival rate at 12 years. This isn't cancer, but it's not too far from it. The best available therapies today can slow the rate of decline, maybe even stabilize in some patients.
If you look at the graph that's in our corporate deck and the data that we presented at EULAR from our phase I/II scleroderma patients, in the vast majority of those patients, we're seeing improvements in interstitial lung disease measurements. In addition, as I said, in more broad measures of how you're doing with your scleroderma. Again, rese-cel with a very attractive safety profile, in our opinion, with the vast majority of patients having very modest side effect profile. We have in scleroderma, a majority of patients with no CRS, some with Grade 1 fever, and we have one or two patients with Grade 2 hypotension that resolved with intravenous fluids in a routine manner over a period of a day or two. We also have in our scleroderma population, a single case of ICANS Grade 3.
I want to revisit this ICANS question here. I want to remind you that about a year and a half ago or more, there was a lupus patient who had a Grade 4 ICANS, the worst ICANS that we know of in autoimmunity. That was in data that we presented in a peer-reviewed setting, shown to be associated with a concomitant infection that was unrecognized in that patient, unrecognized by anybody who was treating and by the company as well. We put in place a protocol change that said you have to look extra carefully for an indolent infection or signs of inflammation and infection in patients before infusing rese-cel. There was a protocol violation of that newly instituted rule. We saw this in this scleroderma case, a Grade 3 ICANS as a result of that protocol violation.
Since that day, which was 15 months ago, we have not seen a single case of ICANS in any treated rese-cel patient. I want to say that again. We all think of CRS as this somewhat burdened and dangerous therapy given to cancer patients historically with all of these terrible side effects. I think that rese-cel is proving itself to be somewhat different. Given in the way that we advise it be given with careful scrutiny for patients who might be suffering from an indolent infection, we have not seen a single case of ICANS, and we've dosed, I don't know, another 60 patients or so since then. We are really bullish on the safety profile of rese-cel to support outpatient use, to support access in settings other than the hospital tertiary care centers in some of these FACT-lite centers.
As Steve will talk to in more detail, the idea to move out into the community and outpatient with speed that frankly has never occurred in the use of any CAR T product. The scleroderma data and why we chose to push scleroderma forward, the objective evidence of a really unprecedented finding relative to anything that's approved today, the unmet need, and the urgency to treat because if I leave it alone, we don't know if that damage is irreversible. There's an urgency to treat in scleroderma that I think is somewhat similar to the Juvenile Dermatomyositis population, where as my child is growing up, if they have this disease and I let it go, what's going to happen to their growth and to their education and to their socialization? There's an urgency to treat in scleroderma that we think matters a lot.
For those reasons, we're really excited to be able to start that registrational trial in the coming months.
All right, great. That's a great segue to the outpatient use and safety profile because you're also the pioneer to test non-preconditioning CAR T-cell, auto CAR T-therapy for autoimmune disease. You just show us in PV last year and early this year, also recent is for lupus, lowest dose for two patients. The data looks impressive, what's the next step of that? How we should think this integrated to your pipeline in a product.
Yeah. We were both impressed and surprised when we presented the pemphigus data recently, PC-free pemphigus data, preconditioning-free. Single dose of rese-cel, nothing else, stop all your medicines, let's see how you do. Two of those four patients treated at the lowest dose of rese-cel, the one that we use with preconditioning, two of the four had durable outcomes at six months. One of the four particularly had all of the hallmarks of somebody who is going to be durably reset over a long period of time, and let's wait and see how that data plays out. For sure it taught us that we are not at the final dose. We need to go higher and we are fully enrolled, I think, in the next cohort and moving. I don't know if we'll move to another cohort or not. We'll be data-driven in our decisions.
At EULAR, we're announcing that we've now dosed the first two lupus patients. Why does that matter so much? Number one, lupus is a crowded and very important target for cellular therapy in autoimmune disease. How do you jump to the front of the pack? Well, the number one driver for market research is get rid of the preconditioning. It's not how fast do I get your cells after the doctor tells me I'm going to get cells. It's not anything other than get rid of the preconditioning. We set about to do that, and we have, fortunately, this large data set of patients who got rese-cel with preconditioning, so we know what good looks like, and we have follow-up of a year or more in those patients. We know who is durably reset clinically.
The translational pharmacokinetic pharmacodynamic markers become highly meaningful in the PC-free lupus patients. We've now dosed two. One of the two looks like they basically are going to be rese-cel.
We're using the lowest dose of rese-cel. The thesis has always been that we're going to need to go to higher doses. We can do that because the safety of rese-cel at the starting dose is so excellent. It all comes back to, as it always does, the clinical data. The clinical data with rese-cel, the safety profile, the efficacy, and now the body of evidence we have with preconditioning gives us the opportunity to go forward with a PC-free regimen and we'll now escalate the dose in lupus and determine how those patients do. Ultimately we expect we're going to select a dose and move forward into a registrational program with lupus, but we're not going to be talking about data points, one or two or three patients any longer. The reason is for competitive purposes.
We are teaching the world how to do this, frankly, we're just not going to do that anymore. We believe this is going to work, we will lead the field into a PC-free future in a way that we will announce what we're doing in due course, I wouldn't expect fast announcements of the next patient or the next three months of data because we don't think that serves anybody's purposes. It doesn't give investors high confidence that it's going to work, it doesn't really serve any other purpose other than teaching the competition how to follow what we do.
Excellent. All right. I think we went through everything we want to chat today for EULAR. Last minute, Steven, if you have anything else you want to highlight, for example, like a Cellares, because that's one of the key thing for the auto CAR T and scalability, or anything else you want to touch last minute?
Yeah. We believe that access will expand with PC-free and that the demand will be strong for myositis, juvenile myositis with the associated voucher and scleroderma to follow it. The question is how do you supply the market and what's your margin? In that regard, having the partnership with Cellares where we've already dosed a couple of patients and presented that data, that the Cellares drug produced rese-cel, at Cellares looks the same as rese-cel produced pretty much anywhere else, sets us up and we are advancing quickly to have the fully automated industrialized manufacturing that has among the lowest cost of goods in the entire industry and does not require capital investment of the sort that we all feared from the past of autologous CAR T.
We think that that sets up for a very happy story when it comes to margins and capital requirements and ultimately meeting the needs of patients.
Excellent. All right. Thank you everyone for watching, listening, and then thank you Cabaletta team to join us. Yeah. Thank you.
Okay.
Thank you.