Good morning, and welcome to the Kymera Therapeutics First Quarter 2023 Earnings Conference Call [Operator Instructions]. Please note that this event is being recorded today. I would now like to turn the conference over to the Chief Financial Officer, Bruce Jacobs. Please go ahead, sir.

Good morning, everyone, and welcome to the Kymera Therapeutics quarterly conference call. I'm Bruce Jacobs, Chief Financial Officer at Kymera, and I'll be joined today by Nello Mainolfi, Founder President and CEO; and Jared Gollob, our Chief Medical Officer. After our prepared remarks, we will open the call to your questions [Operator Instructions]. Before I get started, I'd like to remind everyone that some of the comments that management may make on this call include forward-looking statements, as outlined in the press release. Actual events and results could differ materially from those expressed or implied by any forward-looking statements as a result of various risks, uncertainties and other factors, including those set forth in Kymera's most recent filings with the SEC and any other future filings that the company may make with the SEC. You are cautioned not to place any undue reliance on those forward-looking statements and Kymera disclaims any obligation to update such statements, except as required by law. With that said, I'll now hand the call over to Nello.

Thanks, Bruce, and thank you, everybody, for joining us today. This month marks the seven year anniversary of our founding. And as Kymera reached this milestone, I thought I would spend a few minutes reflecting on the progress we've made on our ambitious plans to build the best-in-class fully integrated global medicines company. Since our funding, we have focused on a target selection strategy that would allow us to use this novel drug modality in target areas that would uniquely benefit from it and on evolving the platform to reach novel therapeutic hypotheses. Over that time, we've continued to enhance our platform capabilities and advance programs in areas of significant patient needs that cannot be meaningfully addressed by conventional medicines building a high-value pipeline and demonstrating our ability to design molecules that have the potential to transform disease treatment. Our first-in-class IRAK4 degrader program, KT-474, is a molecule we discovered and developed through Phase I and is planned to start Phase II trials conducted by our partner, Sanofi. In December of last year, we shared positive early data in both hydrotenatic separativa in atopic dermatitis patients that demonstrated strong translation of our preclinical PK/PD and safety models into the clinic. With this program, we have seen, for the first time, clinical benefits of hydro bifunctional degrader in inflammation and immunology indications for the first proof-of-concept of clinical differentiation of a degrader compared to a small molecule inhibitor. This is a substantial accomplishment for a company that is pioneering a new modality. Sanofi expects to initiate the first Phase II study of KT-474/nHS this year, followed by a study in AD. Our three oncology programs continue to make progress. Of note, we have initiated the Phase I clinical trial of our MDM2 degrader, KT-253. The clinical effect of stabilizing P53 and…

Thanks, Nello. I'll provide a brief recap of where we stand with our clinical programs and what we expect in the coming months. Turning to our oncology pipeline. I want to update everyone on our disclosed programs, which include our Stat3, Aracamid and MDM2 degraders. As Nello mentioned, KT-2503, our MDM2 degrader, received IND clearance from the FDA at the end of last year. We initiated the Phase I trial in March and expect to dose our first patient shortly. MDM2 is the crucial regulator of the most common tumor suppressor p53, which remains intact and close to 50% of cancers. We believe KT-253 has the potential to be a highly potent degrader that unlike small molecule inhibitors has been shown preclinically to have the ability to overcome the MDM2 feedback loop and rapidly induce apoptosis, even with brief exposures. KT-253 has the potential to be effective in a wide range of hematological malignancies and solid tumors with functioning p53. We've shown preclinically that KT-253 has superior activity compared to MDM2 small molecule inhibitors and demonstrated greater than 200-fold improvements in both in vitro cell growth inhibition and apoptosis. Additionally, we presented data at the ASH Annual Meeting last year, supporting an intermittent dosing schedule of KT-253 in acute myeloid leukemia, AML, which has the potential for improved efficacy and safety using a degrader approach. The Phase I trial is evaluating the safety, tolerability, pharmacokinetics, pharmacodynamics and clinical activity of KT-253 in patients with relapsed or refractory high-grade myeloid malignancies, acute lymphocytic leukemia, or ALL, lymphomas and solid tumors. Patients in the KT-253 Phase Ia dose escalation study will receive IV doses of KT-253 administered once every three weeks. The open label study is intended to identify the recommended Phase II dose for KT-253 and will be comprised of two…

Thanks, Jared. I'll quickly cover the financials before turning the call back to Nello for some concluding remarks. Before getting into the specific financial results for the quarter, I wanted to briefly address the events surrounding Silicon Valley Bank as it relates to Kymera. At the time of the receivership of STB, we had very limited exposure to the bank. And in response to the events in March, we removed all of our excess operating cash that was held there and moved the outstanding letter of credit that was also there that is held to support our new lease. At this time, we have modest cash at STB to support our current operating needs. And as a brief reminder, Kymera's investment policy prioritizes protection of principal and our liquidity needs above all and limits our investments to government securities and highly rated corporate bonds. This policy guides our investment approach, and it's been coupled with the recent expansion of our banking and asset management relationships to further diversify our financial risk. That said, back to the financials for the quarter, we recognized $9.5 million of revenue. This total reflects revenue recognized pursuant to our Sanofi and Vertex collaboration. At the end of the quarter, our deferred revenue total on the balance sheet was approximately $57 million. That reflects partnership revenue we expect to recognize over the next several years, excluding the receipt of any potential future milestones. With respect to operating expenses, R&D for the quarter was $42.2 million, of which $4.7 million represented noncash stock-based compensation. The adjusted cash R&D spend of $37.5 million, including stock-based comp, reflects about a 3% decrease from the comparable amount in the fourth quarter of '22. Our SG&A spending for the quarter was $12.6 million, of which $4.7 million was noncash stock-based compensation, the adjusted cash G&A spend of $7.9 million, also excluding stock-based comp, reflects a 10% increase from the comparable amount in the fourth quarter of 2022. And finally, we exited the first quarter with cash and equivalents balance of approximately $516 million. As we shared earlier in the year, we believe our cash runway extends into the second half of 2025 projection, which includes milestones only related to the start of the first 2 Phase II trials for KT-474. I will now turn the call back to Nello.

Thanks, Bruce. I'd like to conclude by reminding everybody that Kymera was funded to harness novel therapeutic approaches to revolutionize the way we treat diseases. Over our seven year history, we built best-in-class discovery engine capable of identifying new drug candidates at accelerated pace and delivering at least 1 IND every year. We now have a pipeline of 4 clinical stage assets across different disease areas, and we continue to invest in the future and evolve our disease-agnostic discovery platform so that we can expand the possibilities of what we can do to improve patients' lives. Propelling a rigorous scientific approach is a relentless desire to do what hasn't been done before to push the boundaries of our signs, expand our capabilities to support a rapidly maturing company and build a culture that enables us to achieve what may have seen impossible. We look forward to sharing exciting updates on our clinical programs, platform and company in the coming months. At this point, I'd like to thank the Kymera team as well as our partners and the patients participating in our clinical trials for sharing this journey with us. Finally, thank you all for participating in our call, and I look forward to your questions. I will now hand the microphone back to the operator so that we can take your questions.

We will now begin the question-and-answer session [Operator Instructions]. Our first question here will come from Vikram Purohit with Morgan Stanley.

This is Gospel on for Vikram. We have one question. So for KT-413 and KT-333, you have mentioned that you would expect those Level 3 and 4 in each program to demonstrate clinical activity. When this it is available, what do you think is going to be the best way to interpret the data to gauge the strength of the clinical activity for each molecule? What is your benchmark for determining good outcome versus a more mixed one?

So first, I'd like just to be clear, we said in December that we expect those Level 3 and those levels 4 to be at clinically active exposures and level of degradation. Obviously, the question will be at those doses, do we see clinical activity, just to be clear. So just to remind everybody, these are first-in-class mechanisms. And for both mechanisms for 413 and 333, we've shown some really compelling preclinical data. Remind you, for 413, we've shown that if you degrade IRAK4 Ikaros and Ailos for about 72 hours, anywhere between 50% and 90% across the three proteins, we can drive midi mutant tumors to complete remissions. For 333, we've shown that if you degrade that for about 90% for about 48 hours, we're able to drive some subset of liquid tumors. We've talked about CTCL, PTCL LGL, leukemias to at least in some preclinical models that we were able to run to complete remission. So the question that we want to ask, we always look at clinical translation from 2 perspectives. The first one is the molecule able to translate what it was designed to do. And so we ask of these 2 molecules to replicate our preclinical degradation profile. So as I mentioned, what we believe it to be clinically relevant is this 50% to 90% degradation for 413 and 90% degradation for 333 for, as I said, 72 hours for 1 program and 48 hours for the second. So as we continue to explore PK/PD and safety in the clinic, and in fact, what we said is that we're going to give an update on ICML on that. We want to make sure that our molecules are able to reach those degradation profiles at tolerated doses and exposures with a tolerated profile. And then the second part of the clinical translation derisking is is that particular degradation profile as he had done in the preclinical studies translating into antitumor effect. And that's going to be the question that we're going to try and answer and show data in the -- later this year, as we said. So it's hard for us to set a bar because just to be clear, we're running a relatively broad Phase I dose escalation studies in terms of patient population. So we will have probably a handful of patients that fit the right criteria in terms of the disease and type of tumor types. And so what we would like to see in those patients is the ability of translation of antitumor effect. And so I think we're staying away right now on comparing and setting a bar just because we're still early in the clinical development. Jared, anything you want to add to that?

No, I think that covers it all.

Our next question will come from Michael Schmidt with Guggenheim.

Just a follow-up on 333 and the 413, as you think about this upcoming update at the ICML conference, can you talk about a bit how far in you are in those two Phase I studies now beyond dose over one or two? How many patients were the data do you have at this point, or how are you tracking towards identifying a recommended Phase II dose? And then on 413, I think you already had 95% to 100% knockdown of Ikaros and Ailos last December. I guess, how much higher do you need to go? And how confident are you in not seeing issues around potential on-target toxicities related to those two targets that you go much higher.

We really haven't been guiding externally in terms of where we are right now with regards to enrollment across both the studies. As we showed back in December, we presented data on DL1, the first dose level for KT-333 on the first two dose levels for KT-413. And all we can really say is that we're continuing to enroll across both studies. And when we do present updates at ICML, at that time, we'll be able to really update on numbers and where we are in terms of which dose levels. In terms of the knockdown question, yes, you're right that with regard to 413 and Ikaros and Ailos knock on, we did show a very robust knockdown of greater than 90%, 95% in peripheral blood, in particular, with those first two dose levels is the data we shared back in December. For IRAK4, I think at that time, we had approximately 40% knockdown of IRAK4 in the blood. We had one serial set of tumor biopsies from the first dose level where we showed around 60% knockdown of Ikaros and Ailos and tumor and around 20%, 25% knockdown of IRAK4. And so I think what we want to be able to show in subsequent dose levels is continued strong knockdown levels of Akoros and Ailos levels in the blood, we'd like to see further knockdown of IRAK4, getting up into that 50% to 70% range that Nello alluded to earlier is associated with antitumor activity in our preclinical models. And if it's possible, where we can get voluntary, tumor biopsies also continue to show activity there as well.

I just want to add one thing, Michael, and probably for everyone's benefit. I think it's an exceptionally exciting time to be at Kymera. We have the luxury of witness what is first-class in mechanisms, translation into patients. We've done it with direct for and now we're doing with three other mechanisms. So I don't think we're trying to deflect questions. It's really like we are observing new biology at play here. And so for -- especially for STAT3, there is a wealth of opportunities that we want to be thoughtful on how we're exploring.

Our next question will come from Brad Canino with Stifel.

I feel like I'm going to ask Michael's questions in a different way because I just want to check on the upcoming Lugano presentation. Will that include additional patient numbers and dose cohorts relative to last December's disclosure? And then a specific question on KT-413 as we watch these safety data evolve through the rest of the year, as you dose escalate, do you have a range of neutropenia across grades that you're going to be comfortable with, especially when you think about marching this drug eventually to earlier lines in the treatment paradigm, which will be in combination with the DLBCL standards of care?

Yes, I know, and that's a great -- thanks for asking again because maybe we weren't clear enough. Yes, there will be more data, obviously. Otherwise, we wouldn't be presenting an ICML. There will be meaningfully more data on the programs that we present. On the -- maybe I'll let Jared comment on the neutropenia question. I just want to repeat something we've said before, which is the opportunity with 413 is the ability to translate synergistic biology between IRAK4 and Ikaros and Ailos. And that's really the question. The question is, is this synergistic biology that we've seen preclinically, being able to drive profound antitumor effect driven by an immediate apoptotic response that only required 72 hours of knockdown? Is that going to translate in the clinic? If it is, I think we will be able to navigate much better than other programs, the question around neutropenia because we have this apoptotic dosing, which allows us to capture this immediate apoptotic response in the first few days and then allow any potential on-target safety coming from the image part of the pharmacology here to be managed by the -- again, the alternative dose in PARADIGM. Jared, anything you want to add on the actual grade type of neutropenia here?

In terms of neutropenia, I mean, clearly, we're referring to the neutropenia that is seen with IMiDs, especially with potent IMiDs. And as we noted back in December with the first 2 dose levels on 413, we didn't see any neutropenia adverse events. We do expect, based on our preclinical animal tox data to see lowering of neutrophils as we continue to dose escalate. The issue isn't whether we'll see lowering in neutrophils. The issue is really what is the recovery time. And because we have this every three week dosing, which is one IV infusion every three weeks in our GLP tox studies, we saw that, that gave us adequate time to see recovery of neutrophils after they were suppressed as well as recover real lymphocytes. And so I think the key here for us will be, as we escalate, we do expect to see some lowering in neutrophil where we see recovery prior to each dose. And I think that will tell us a lot about the therapeutic index and tolerability and the ability of this intermittent dosing regimen to mitigate that particular toxicity, which is seen commonly within.

And our next question will come from Chris Shibutani with Goldman Sachs.

Following some of those specific questions on the assets. Nello, you noted the anniversary. Perhaps can you comment on a couple of things in terms of how you're thinking about the next phase of strategically optimizing your portfolio development and capital allocation. When we think about the oncology assets, there's kind of a fleet of them that seem to be going in tandem. You know investors like to pay attention to kind of like a lead steer as kind of a catalyst driver. Do you anticipate that the timing of these oncology assets will also be kind of in this couple or the trio? And then in terms of next areas that you could roam, you have the Sanofi relationship for the first immunology asset, but there's other potential immunology indications. I believe you brought on board someone more with the sort of business development, strategic investment banking role in-house. How are you thinking about taking that next tranche of assets so that you can optimize the capital that you have?

It's a great question, which I could spend a day on, but I'll try to do it in a couple of minutes. First, I'd like to recognize the path that we've taken from an early company that was sitting on a potentially transformative new drug modality and decided to commit to building a real company. I use often this definition of a real company, meaning committed to seeing programs through the different phases of development and eventually commercialization because we believe that in order to capitalize on the power of this really, really strong new modality, you have to commit to see it through. You cannot depend on other industry partners to do so because that's what history has taught us. New modalities have been developed in biotech companies and biotech companies only at best. So that's our commitment. Now the first seven years have been a year's full of execution, but also learning. We learned the type of targets that best benefit from this technology. And we've shown we were fortunate enough that our early targets have played out, I would say, extremely well into early clinical development, demonstrating the power of the technology. We've also learned and maybe not discuss broadly enough, the type of targets we don't work well with this technology. And we've been -- I think we've been focused, and we've been really good at understanding early on the type of targets that is not worth applying this technology again. And so our first wave of targets, I think, are well positioned to demonstrate with the catalyst rich sequence, the power of degrading targets in human patients and then the power of that degradation impacts on human disease and human condition. So I would say the next two years, we will see proof of concept…

Our next question will come from Marc Frahm with TD Cowen.

Maybe just to start one right after ICLML the guidance for initial MDM2 data midyear. Can you just walk through again the target degradation profile there, both in terms of depth, but also kind of the timing of those -- that degradation?

So this is MDM2, right? So MDM2, just to be clear, we'll not be presenting an ICML, maybe I misunderstood, but…

[Indiscernible] right after…

So I think what we're presenting in the short term on MDM2 preclinical data at the EHA conference. Later in the year, we will be presenting early clinical data. And what we call this proof of mechanism just to be clear is how much degradation we see in early cohorts and what is the safety profile, which for this program, it's going to be meaningful because in a way, all MDM2 programs in the past have suffered from ability to engage the target fully and managing the right safety profile. So we haven't really actually talked deeply about what is the degradation profile and the extent of degradation needed to achieve kind of full biological response in preclinical species. What I will say and I believe we're presenting more data also later in the year on these, again, preclinical data is really elegant work that the team has done. And even at EHA, I believe we will talk about how dose and dosing type what the impact the biology in this pathway. But what I will say is in order for us to overcome this, we call a feedback loop of MDM2 transcription regulation, we need to have a deep MDM2 degradation that is actually limited even I would say, in terms of hours, not even days. Once we are able to knock down MDM2 for a short period of time, but deeply, we see a profound commitment to sell that of a wide variety of tumor types. And we have seen -- we observed that, that commitment to apoptosis is enough to not require another dose for weeks. In fact, we're going into the clinic with this program with once every three weeks dosing. So what we're trying to do in the first, again, innings of this program is to demonstrate again that we're seeing these profound degradation in the early few hours, and we're also seeing a manageable safety profile, which in preclinical species, we've characterized, and we feel really confident around.

And then maybe back to the 333 and 413 trials. As you mentioned earlier, the enrollment criteria is pretty broad and not necessarily in the early parts focused entirely on the patient population who might have the most robust singulation activity. But are you seeing a real bias kind of in the enrollment just given that there is some testing, particularly from MYD88, out there towards the target populations, or should we think the epidemiology is really what we'll see?

I think as you've noted, the 413 study is broadly enrolling B-cell non-Hodgkin's lymphoma on Phase Ia. We do have sites that are enrolling patients, and these are sites that have the ability to identify MYD88 mutant patients as well, either with DLBCL or Waldenstroms -- and so as we get into higher doses, those sites know that those are patients of interest. And as Nello alluded to earlier, we'd like to be able to have some of the targeted indications enrolled onto the study as we get into those higher doses to give us an opportunity to show initial antitumor activity. And likewise, for the STAT3 program, we're broadly enrolling solid tumors as well as B and T-cell lymphomas on Phase Ia. But likewise, we also have a number of sites that do have CTCL, PTCL and LGL patients and those sites are capable of putting those patients onto the trial, especially as we get into those higher pharmacologically active doses. So once again, we would have an opportunity to show antitumor activity in those target indications.

And our next question will come from Mike Kratky with SVB.

Regarding the KT-474 data to be presented at EADV, will there be any new analysis included in these results, and what incremental new info could we expect to get?

No. So in our oral presentation, I think it would be a summary of data that we've already shared. What I will say is that, as we said in the past, we're working on a manuscript that will have maybe more insights into the data. But for the presentation, I would expect it to be what we've shared in the past, given that it's also a relatively short presentation.

And our next question will come from Eric Joseph from JPMorgan.

This is Hannah for Eric. Just wondering how many dose levels you're planning to evaluate in the KT-253 dose escalation study. And based on that, at which level would you expect to be as pharmacologically active doses? And are you commenting on the specific doses that are being evaluated in that study? And then secondly, can you comment at this time on the expected biomarkers that are being used to evaluate MDM2 degradation? And how quickly do you expect these to begin to change in response to degradation?

We haven't really commented publicly on how many dose levels are in that study with the doses that we're actually planning to prosecute. I mean whenever we bring dose into our Phase I studies, it's based on our preclinical data on our GLP tox studies, and we usually have an expectation that even the lower dose levels will have the potential ability to result in some downregulation of the target. But we really haven't provided specifics on that. With regard to sort of measuring pharmacology in addition to looking at MDM2regulation, we do have other biomarkers that are included in the study that help us look at p53 pathway activation because as you know, if we're hitting MDM2 the way we want to, we should see upregulation of p53 pathway and the various biomarkers that are associated with that activation. So we've built this into our Phase I study that we'll be able to measure these different biomarkers in the blood as we proceed with dose escalation.

Maybe the only thing to add, I would say, if you look at all the programs we've disclosed of the first dose has always been dosed with measurable levels of degradation. So I think we expected that to be in line, obviously, but we have to run the study to see.

And our next question will come from Zhiqiang Shu with Berenberg.

This is Andy on for Zhiqiang. The first question is, so for your STAT3 program, I think you communicated the knockdown or the degradation window. And I'm just wondering like what's the ideal therapeutic window that you're targeting and if there's any clinical rationale for that? And the other question is your STAT3 and IRAKIMiD program, what's your ability or willingness to make them orally available?

So the first question is -- so we've said this in the past, empirically through lots of work that we've done preclinically, we've shown that degradation profile where you have about two days or 48 hours of deep degradation around 90% or even more and then recovery of the degradation over the course of the duration of the week or even two weeks is sufficient to drive strong antitumor effects in a wide variety of tumor types. And that profile is also really well tolerated. So this is the hypothesis that we're bringing into the clinic. Once a week, we could actually dose even once every two weeks, but we decided to start with once a week and being able to drive that profound degradation in the first 48 hours or so of that particular program. And so that's what we're bringing forward. That is both effective and really well tolerated in preclinical species. With regards to oral, I mean, this is really around -- when we start the program, we usually start with the TPP based on the mechanism. And if the males is unknown, it usually is driven also by what we learned along the way. So in both of these programs, the biological and translational hypothesis has been in frequent dosing because we need to manage both the activity as well as the recovery of the target and the building of the therapeutic index. And the fact that we were able to use the distribution and the PK of this compound to maintain degradation for multiple days with a single dose. So naturally, that type of profile led to this infrequent dosing, which is -- it's a lot more manageable if you do it by parenteral administration. These two programs are not IV because these molecules are not orally but available. At least we've shown for the 413, this actually started as an oral drug, and we were dosing it every day in preclinical species early on in the development of the program, and then we switched it to a different dosing paradigm, again, to manage both the activity and the safety.

And our next question will come from Ellie Merle with UBS.

This is Jasmine on for Ellie. On the MDM2 program, we know that RR AML has been disclosed as a particularly sensitive tumor type to MDM2 degradation. So when we're thinking about other tumor types that could also be potentially sensitive in this mechanism. Can you give any color that would help us understand the characteristics of the kinds of tumors you might be?

Jared, do you want to take this? I think the question was around probably AML.

Well, I think the question was that AML. We assume that to be a sensitive tumor in our model systems, what are we doing on solid tumors? And even though we haven't presented as much data on solid tumors, what we can say is that we've been doing a lot of work preclinically to identify those solid tumor types that have the same sort of exclusive sensitivity to MDM2 degradation that AML has where we can dose intermittently as we can with AML once every three weeks in tumor models and see profound tumor regressions. And so we have identified various solid tumor cell lines and perhaps will later this year be able to reveal what some of those are at presentations. But we have been number one, looking at those different solid tumor types to determine those that are very sensitive to this mechanism. And number two, we've also had an active effort in trying to nail down potential biomarkers that are associated with the most responsive subsets of those different solid tumor types that could allow us to then use that to select patients moving forward as we go beyond Phase 1. So I think this is an active area of research for us and very important that for us, it's not just going where other MDM2 have found before in terms of solid tumors, it's really really forging our own path based on our preclinical data, making sure this is a data-driven decision with guys with solid tumor types, we end up exploring as we get beyond Phase I.

And I would also add that encourage everybody to kind of follow as we disclose more preclinical data. I think for both -- for these broad mechanisms, both KT-333 with that three and MDM2 with 253, these are both applicable mechanism in a wide variety of systems. We're covering some really, really fascinating, I would call it almost new biology, both alone and in combination with interesting agents where you can see really meaningful path of patient impact when you have this new modality that can be combined with existing mechanisms. So stay tuned, and you'll see much more of those in the upcoming medical meeting.

And maybe also just to quickly add that, again, in our Phase I study, we have a one arm, which is solid tumors or lymphomas. And then a second arm, which is AML and ALL and other high-grade myeloid malignancies. We then plan in Phase Ib on having expansion cohorts, one of those will certainly be AML, but we also plan to have expansion cohorts in select solid tumors based on activity that we see in Phase Ia and also based on activity that we're seeing in our preclinical models.

And our next question will come from Timur Ivannikov with Raymond James.

So I just wanted to come back to QTC pronation for a moment. So recently, one of the players in TPD reported a grade four prolongation event in our study of synovial sarcoma. So could you just remind us in your preclinical testing for the newest assets like 413, 333 and 253, did you see an interaction with ion channel streclinically? And I think in the past, you've talked about a potential saturation effect on interaction with the ion channels. Do you still believe that's the case?

So I would say that we can see with confidence that QT prolongation is not a class effect. I mean, as you know, QT prolongation is or QTC prolongation is something that we've seen in the industry for the past 20 years since we discovered -- and actually, we understood more since we discovered the Ion channel, and it's impacted many small molecules. So I think this is a molecule-specific phenomenon that we have seen in the industry, and I suspect we will continue to see. I think I want to remind you that there have been several degraders in the clinic. And I think the example you bring up is just one out of several examples where we have not seen QTC prolongation. With regards to KT-474, and Kymera, I think what we've said is that we've seen something that is very unique, which is a time-limited effect where we see appearance of the subclinical QT that then resolves spontaneously with continued dosing. And that's a very atypical phenomenon. And we believe it's driven by a compound distribution that requires some time to reach steady state, and it might initially have higher exposures around the intracellular compartment of cardiomyocytes that express the ion channel. That's just an hypothesis. But this is not the typical QT prolongation, which is often dose responsive and concentration response, which is what you see with most molecules. I don't know enough about what happened in the other company with that particular drug. I suspect that it's a different -- probably it's a different mechanism, given that they've seen it all at the high dose. I remind you that we've seen kind of the same subclinical finding, obviously, not a grade four. It was subclinical across all the four doses in our MAD study. So again, saying that this was a different mechanism than a normal Q2 driven by [Indiscernible]…

And our next question will come from Kelly Shi with Jefferies.

This is Sean on for Kelly. We have a question on HS with a rapidly evolving landscape. Can you share how your thoughts and positioning of KT-474, have evolved in light of the recent development in the space, specifically has any of the recent competitor data being factored into the Phase II trial design, the selection of efficacy endpoint, et cetera?

It's a great question talking about patients also. HS is a higher met need, we all know. I don't believe that HS is driven by a single cytokine. So I'm pleased to see that IL-17 agents work. I don't believe that IAS-17 is the solution to HS. But it is going to be a great tool in the arsenal of tools that doctors and patients will have. So I think it's great to see this evolving class of antibodies and the likes that are being developed in the space. This is a broad inflammatory disease, local and systemic that we believe requires a broad anti-inflammatory agent. And we believe that IRAK4 is uniquely positioned to be both active and well tolerated and have -- and obviously, be an oral agent. So our view of the unmet need and the opportunity for an oral active agent has not changed. There is still a high unmet need, and we believe we can have an opportunity to have a broad impact in this disease. In terms of how we think about trial design, I wouldn't think that we have learned what we've seen from elegant studies that have been run is really validation of what are the key primary and secondary endpoints that one wants to see to confirm activity of drugs. And I don't believe we've learned anything that has changed our view on how we want to design our clinical study, which obviously, we've done in collaboration with Sanofi on Phase II. So I think it's great to see, again, other agents being active. The opportunity is totally still there for an oral active drug in that space that is, again, active and well tolerated.

And we have time for one more question, which will come from Rich Law with Credit Suisse.

This is Grace on for Rich. The first one is what's the development path and timelines for the STAT3 program in combo with PD-1 and do you see any other combo regimens that will make sense?

So yes, the answer to the second question is, yes, we see several combo opportunities here. And this is a bit what I was referring to earlier. We -- had the beauty of working with the new machines, we are learning also with some of our academic collaborators that have published and will continue to publish on this. What STAT3 biology can be combined with to drive synergistic antitumor effects. With regards to timing, so we're now focused, as you know, on dose escalation as single agent, and we're obviously learning also when we can, when patients allow for biopsies also what's happening in the tumor microenvironment, that's one of the goals that we have. And any combo will be part of laser expansion cohort, which will happen after we conclude Phase Ia.

Operator, we probably can take one or two more. So if you want to go to the queue, that would be great.

Our next question here will come from Geoffrey Meacham with Bank of America.

This is Hao calling in for Jeff Meacham, and thank you so much for [Indiscernible] accepting for the question. So I think you touched on this, so just a follow-up for KT-413, could you talk about the choice of the Q3W. We see recovery of across Ailos and to some extent, IRAK4. If it's helpful for the neutral opinion, could you talk about data, maybe some implication on the efficacy side that you have seen?

I mean we've shown in our preclinical models, and we've run multiple preclinical xenograft models of both CDx and PDX models of MYD88 mutated DLBCL. And very consistently in those models, we've shown that a once every three week IV infusion results in complete responses that are durable. So I think we're feeling fairly confident in the ability of a once every three week regimen to illicit activity in the target patient population. And that comes back to what we've learned even in vitro and washout experiments, but we know that these MYD88 mutant cell lines, if you not -- these targets down for about 72 hours, that commits these cells to apoptosis. And that's why we think we're seeing these profound antitumor responses in the xenograft models. With regard to the every three week dosing and safety, we've learned from our GLP tox studies that when we do see a drop of neutral accounts, which is really driven by the mid activity of the drug, we can see a nice recovery of those accounts prior to the next dose three weeks later. And that's why we think that we anticipate having an acceptable therapeutic index with an every three week dosing regimen, while at the same time, still being able to maximize clinical activity even with that sort of intermittent dosing schedule.

And our last question here will come from Kalpit Patel with B. Riley.

Maybe one for IRAK for the greater the landscape. There have been other recent collaborations in the industry for developing IRAK4 degraders. I guess from the available information for these other molecules, are there any specific points of differentiation that you want to highlight? And maybe what early metrics do you think it might be crucial to focus on when making comparisons?

I would say we're very proud of having initiated a new field year with Eric and I'm being serious. So I think it's good to see that the mechanism has been recognized -- finally recognized once you have the right approach and in this case, with a degrader approach. We have a drug that is quite exceptional. We can degrade the target 95% plus. We can degrade in the skin and in the blood. We've seen some really exciting early data in both HS and AD, it's a profile that it's going to be hard to match. I don't know which molecules others are advancing. I know that there is a collaboration in which a molecule was, I think, option at DC. So clearly, a couple of -- at least a couple of years behind. I think there are also other molecules. We just don't know what those molecules look like. We haven't seen any presentations of any type of data. So it's hard for me to point to something besides saying we have a really, really good molecule would be hard to match PK/PD activity and safety. And obviously, we're also further ahead in competition.

And this concludes our question-and-answer session. I'd like to turn the conference back over to Nello Mainolfi for any closing remarks.

Well, thanks. I want to thank everybody for joining our call today. It's been an exciting first quarter for 2023, starting from early in the year when we announced some of strategic choices that we've made in terms of where we're taking our discovery engine and platform with some fees on the new programs. Also, we've been talking about where and when we would be disclosing our oncology data across our pipeline, both preclinical and clinical, we'll have in the next seven weeks, actually presentation across the whole clinical pipeline, 474 at the ATB, then we'll have MDM2 preclinical in this case, EHA. And then we have both KT-413 and 333 at ICML. And then we have more data in the second half of the year. And this is really what this company will continue to be producing clinical data in first-in-class mechanisms with broad clinical potential and expect that in the next two, three years, we'll have a large pipeline with continued cadence of clinical readouts. So it's an exciting time. The first seven years of Kymera has been a fun ride, but the more exciting will be the next seven. So thank you very much for being on the call and looking forward to more interactions in the next few weeks.

The conference has now concluded. Thank you very much for attending today's presentation. You may now disconnect your lines.