Kymera Therapeutics, Inc. Q3 FY2022 Earnings Call

Welcome to the Kymera Therapeutics Quarterly Conference Call. Leading the call from management are Nello Mainolfi, Founder and CEO; Jared Gollob, Chief Medical Officer; and Bruce Jacobs, Chief Financial Officer. Before we get started, I would like to remind everyone that some of the comments that management makes 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 these forward-looking statements, and Kymera disclaims any obligation to update such statements. I will now hand the call to Nello Mainolfi, Founder, President, and CEO.

Thank you, Operator, and thank you, everybody, for joining us today. We're very excited to share with you the progress we've made over the last quarter and how it contributes to achieving our mission to build a best-in-class, fully integrated global degrader medicine company. We recently completed the patient cohort portion of our KT-474 Phase I clinical trial, which concludes the Phase I campaign for this drug. Jared will share more details in his remarks, but with the study completed, we're currently in the process of collecting and analyzing all the data. We plan to share, as we always do, the data and the analysis of the data with our partner, Sanofi. As announced, we will subsequently share the data publicly on a company webcast on the morning of December 14, 2022. As we have reiterated in the past, the objective of the patient cohort is to confirm that PK/PD and safety in patients with AD and HS is consistent with what was demonstrated in the healthy volunteers in the SAD and MAD cohorts. As we announced last month, we plan to update investors also on our clinical oncology pipeline on the December 14 call. As I believe you all know, we have 2 clinical-stage programs, IRAKIMiD KT-413 and STAT3 KT-333, and 1 program that we expect to enter the clinic soon, which is our MDM2 degrader KT-253. With respect to the ongoing trials, the KT-413 and -333 are both in dose-escalating stages of our Phase I portion. As a reminder, the objective in this early dose cohort is to demonstrate what we call a proof of mechanism, which we define as the ability to degrade the proteins of interest, which obviously is STAT3 for 333, and for 413 is IRAK4 and even substrates Ikaros and Aiolos, with an advanceable safety profile. Again, Jared will share more here as we go into the call. Along with our clinical progress, we continue to work to ensure that we have the resources to build our company in a sustainable way and continue to invest in our clinical program, discovery pipeline, platform, and team. To this end, in August, we raised an additional $150 million through a private placement equity financing led by a broad group of really committed, strategically aligned, and long-term-oriented investors, each of whom demonstrated their confidence in the team and shared our optimism in Kymera's future. As a result, we ended the third quarter in a very solid financial position, with approximately $596 million in cash. Before I turn the call over to Jared, I also wanted to take a moment to recognize the change we announced today on our Board of Directors. As many of you have heard me say, we have started to build Kymera into a fully integrated biotech company and to sustain a leadership position in both PPD as well as in biotech. As we work to achieve this mission, we obviously will continue to build both an employee base as well as a Board of Directors that bring all the requisite knowledge and experience to support our success. To that end, we're pleased to announce that Dr. Victor Sandor has joined our Board of Directors. For those of you who don't know Victor, he has deep expertise in the global clinical development of medicines that have significantly impacted the lives of patients, especially in oncology. He was most recently the CMO at Array BioPharma prior to its acquisition by Pfizer and has had an impressive career in the biopharmaceutical industry. Importantly, at the same time, I also would like to recognize and thank another director, Don Nicholson, who will be leaving Kymera as director after having served for the past 5 years and having started just shortly after the company's formation. Don is one of our longest-tenured directors and has been an important contributor to Kymera's growth and success over the last 5 years. We're very thankful for all of his important contributions and wish him the best. With that said, Jared will now cover in greater detail our recent progress for each of our disclosed programs before turning the call over to Bruce for a financial update. I will then finish with some concluding remarks before handing the call back to the operator for a Q&A session in which Jared, myself, and Bruce will be available.

Thanks, Nello. I'm excited to share updates on our 3 clinical programs. I'll begin with our IRAK4 program. KT-474 is a potentially first-in-class oral degrader of IRAK4, a key protein involved in inflammation mediated by the activation of toll-like receptors and IL-1 receptors. KT-474 is being developed for the treatment of TLR/IL-1R-driven immune inflammatory diseases, such as hidradenitis suppurativa, atopic dermatitis, and potentially others. As you may recall, Part C is an open-label study of KT-474, administered daily on an outpatient basis for 28 days, with patients followed through Day 42. As we shared last month, we've completed dosing in the patient cohort, or Part C of our Phase I trial for KT-474. Additionally, we can confirm today that all patients have completed their last visit, or Day 42 of the study. The Part C patient cohort followed the dosing of over 100 healthy volunteers in the single ascending dose and multiple ascending dose portions of the Phase I trial. In the SAD and MAD studies, we demonstrated near-complete IRAK4 degradation in peripheral blood mononuclear cells and skin, robust inhibition of multiple ex vivo stimulated disease-relevant cytokines, and a favorable safety profile. Part C includes patients with either moderate to severe hidradenitis suppurativa or atopic dermatitis and is examining the safety, pharmacokinetics, and pharmacodynamics of KT-474, while also exploring early signs of clinical activity. Patients received a daily dose of 75 milligrams of KT-474 in the fasting state. This dose is expected to provide a plasma exposure that is approximately equivalent to that achieved with a 100-milligram per day dose in the fasting state in healthy volunteers in the MAD portion of the trial, which showed maximal or close to maximal degradation in blood and skin and broad disease-relevant cytokine inhibition ex vivo. As previously mentioned, the goal for this study is to confirm that our PK/PD and safety profile in patients is in line with what we have seen in healthy volunteers. In December, we plan to share data on the impact of KT-474 on IRAK4 levels in PBMC and in active HS and AD skin lesions, as well as on the expression of co-inflammatory gene transcripts in skin lesions and on plasma biomarkers of inflammation. We are also undertaking an exploratory assessment of early impact on clinical endpoints, including Eczema Area and Severity Index, or EASI, for AD; inflammatory nodule counts for HS; as well as symptom scores and global assessments of disease severity for both AD and HS. As we have noted in the past, it's important to consider that this is an open-label study, without placebo, in a small number of patients and one in which we do not expect to reach steady-state IRAK4 degradation in skin until the second half of the 4-week dosing period. And as a result, the data on early signs of clinical activity should be viewed through that lens. We will also be following safety and tolerability in Part C. And as a reminder, in our SAD and MAD studies, KT-474 demonstrated no serious adverse events and only a few mild to moderate adverse events. Our December update will include a comprehensive safety analysis, including whether the modest non-adverse QT prolongation that we observed with multi-dosing in healthy volunteers that plateaued after 7 days continued to show evidence that it is self-limited; but in this case, out to 28 days. Before I conclude my remarks, I will update everyone on our disclosed oncology pipeline which includes our STAT3, IRAKIMiD, and MDM2 degraders, the first 2 of which are in the dose escalation stage of their ongoing Phase I trials. As mentioned, our December webcast will include an update on our pipeline. As a quick reminder, STAT3 is a transcriptional regulator that has been linked to numerous cancers and other inflammatory and autoimmune diseases. Our Phase I clinical trial is evaluating KT-333's potential in hematological malignancies and solid tumors. Specifically, the trial is evaluating the safety, tolerability, PK/PD, and clinical activity of KT-333 in adult patients with relapsed and/or refractory lymphomas in solid tumors. We have been recruiting broadly in Phase Ia dose escalation across solid and liquid tumors in order to reach pharmacologically active doses as soon as possible before then focusing on patient populations where we expect to see clinical activity, either as a monotherapy or in combination with other agents. The trial in the second stage will consist of 4 Phase Ib expansion cohorts to further characterize the safety, tolerability, PK/PD, and antitumor activity of KT-333 in relapsed and/or refractory peripheral T-cell lymphoma, cutaneous T-cell lymphoma, large granular lymphocytic leukemia, and solid tumors. In September, KT-333 was granted its second orphan drug designation by the U.S. Food and Drug Administration for the treatment of cutaneous T-cell lymphoma, following its orphan drug designation for peripheral T-cell lymphoma earlier this year. Our IRAKIMiD program, KT-413, is a novel heterobifunctional degrader that targets degradation of both IRAK4 and the IMiD substrates Ikaros and Aiolos with a single small molecule. KT-413 was designed to address both the IL-1R/TLR and the type 1 interferon pathways synergistically to broaden activity against MYD88-mutant B-cell malignancies. KT-413 is on a similar timeline as STAT3 and is currently in the dose escalation stage of the Phase I trial evaluating the safety, tolerability, PK/PD, and clinical activity of KT-413 in patients with relapsed and/or refractory B-cell non-Hodgkin's lymphomas. Similar to the strategy I just described for the KT-333 Phase I, we are enrolling a broad population of B-cell lymphoma patients, after which we will focus on patients where we expect to see the most substantial clinical activity. Specifically, the second stage will consist of 2 Phase Ib expansion cohorts in DLBCL to further characterize safety, tolerability, PK/PD, and antitumor activity of KT-413 in relapsed/refractory MYD88-mutant and MYD88 wild-type DLBCL. Finally, KT-253, our MDM2 degrader, has completed IND-enabling studies and is on track to achieve IND clearance by year-end. MDM2 is a crucial regulator of the most common tumor suppressor, p53, which remains intact in more than 50% of cancers. Kymera is developing a highly potent MDM2 degrader that, unlike small molecule inhibitors, has been shown preclinically to have the ability to suppress 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 or wild-type p53. We look forward to updating investors on our pipeline in December.

Thanks, Jared. For the quarter, we recognized $9.6 million of revenue, a total that reflects revenue recognized pursuant to our Sanofi and Vertex collaborations. At the end of the quarter, our deferred revenue total on the balance sheet was approximately $77 million. That reflects the partnership revenue we expect to recognize over the next several years, excluding the receipt of any future potential milestones. With respect to operating expenses, R&D for the quarter was $43.9 million. About $4.9 million of that represented noncash stock-based compensation. The adjusted cash R&D spend of $39 million, which again excludes the stock-based compensation, reflects a 7% increase from the comparable amount in the June quarter. With respect to G&A spending for the quarter, it was $10.6 million, of which $4.2 million represented noncash stock-based compensation. That adjusted cash G&A spend of $6.4 million, again excluding stock-based compensation, reflects a 5% decrease from the comparable amount in the June quarter. We exited the second quarter with a cash and equivalents balance of approximately $596 million. Recall that we do not include in our cash runway any payments from milestones that we have not yet achieved. Our guidance for cash runway of at least into 2025 incorporates the completion of our $150 million PIPE, but we do plan to update this runway guidance, in particular, the specifics around the extent of runway extension driven by the financing, closer to year-end.

Thanks, Bruce and Jared. As we look forward to providing a clinical update on our December webcast, it's clear that Kymera has successfully transitioned into a new phase, one in which we can observe our science in action in patients. We are excited to begin to assess the impact that 3 of our programs may have in patients with cancer and immunological conditions and to finally demonstrate the advantages of our platform over traditional medicines. With all the progress made this quarter, we're just getting started. In addition to our 3 clinical programs, we're on track to clear an IND for our MDM2 degrader, KT-253, this year, and we're advancing several earlier programs with clear degrader rationale and significant commercial opportunities. So with the productive partnerships in place with Vertex and Sanofi, with our recent financing, we continue to maintain an array of pipeline investment opportunities to maximize the potential of our best-in-class platform and discovery engine. At this point, I'd like to thank the Kymera team as well as our partners, the patients who are participating in our clinical trials and, finally, all of you for participating in this call, and I look forward to your questions. I will now hand the microphone back to the operator so we can take your questions. Thank you again.

First, can you tell us when you expect to deliver the data package to Sanofi in relation to that December 14 date you've set up? And will the package be based on the 28-day data cut? Or will it include the 2 extra weeks of follow-up? And then, Nello, I want to go back to your R&D Day last year. You set an ambitious suite of goals for 2022, which included the first tissue-restricted, E3 ligase-enabled program in development. Can you just update us on that status and perhaps share any comments regarding the critical decision points remaining for the target in E3 ligase selection for that first candidate?

Great. Thanks, Brad. Two great questions. So one at a time. So the first one, we plan to deliver to Sanofi the complete data package. So obviously, that will include also the follow-up period of the extra 2 weeks of observation. I think today we're saying, and it's also on clinicaltrials.gov, that we have completed that phase as well. So when we say the study is completed, we mean that every patient has gone through also the 2 weeks of follow-up. What we've also said today is that we're still collecting and analyzing data. So the phase of data collection is not completed yet. As soon as we complete that phase, we will share the totality of the data with our partner. So we haven't said when that will happen because, to be honest, we haven't completed all the work that we're doing internally. Maybe the only thing I would add is that we've always had a very close relationship and communication with the Sanofi team, so we try and be as helpful as possible also in this time when we're still collecting data to make sure that we share anything meaningful as we collect things. To your second question, as I said, we have several programs in the preclinical stage, many of which are actually close to entering preclinical development. And one of those programs entails the use of an E3 ligase that has a restricted expression in the body that will allow us to actually overcome the dose-limiting toxicity of a well-known oncology target. I think our plan, although we haven't firmed it up yet, is to provide an update at some point next year on where those programs are. Maybe we'll disclose. We'll see 1 or 2 of them, depending on which stage of development they are. So I guess it's not super satisfying but I'd say stay tuned, as more information will be shared on that.

Just to be clear in terms of the optionality for Sanofi and the decision that they'll make, we may hear from them that they would proceed with both programs, one or sequentially, the way that you've structured your relationship there? Just so that we can frame the different scenarios that could play out, that would be helpful. And secondly, on the KT-333, there is scientific premise for pursuing indications outside of oncology. Any thinking there in terms of how you would pursue that? Would that be with partnerships? And does Sanofi have any opportunity to explore that as well?

Chris, if you can stay on the line for one more second, can you clarify your first question when you said 2 programs? I'm not sure I fully understood the question.

Just thinking about the 2 indications for AD and HS. And so perhaps clarifying that we shouldn't be thinking that the decision from Sanofi is singular and binary but that there's sort of an option set.

Sorry, Chris. I missed that. So thank you. So going back to the question then, so as you know, we are in this partnership with Sanofi on IRAK4 degraders outside of oncology and immunology. That's actually the spirit of the contract. And both Sanofi and Kymera have large ambitions. We believe that this mechanism has the potential to be one, if not the best, small molecule anti-inflammatory drug in a wide variety of diseases. Obviously, we'll have to generate data to support our beliefs here, but that's what we're doing. So when Sanofi will make the decision to transition, if and when they make the decision to transition, KT-474 into, we call it, late development, it's a decision to invest into the global development of the drug. And so it's not indication-based but it's in late development. We, as a partnership, have always been aligned that the reason for Sanofi and Kymera to partner is to use and benefit, at least from Kymera's point of view, benefit from the broad clinical and commercial footprint that Sanofi has built in immunology. And as they say publicly, they want to be the number one immunology company in the world. And so the spirit of the collaboration has always been to try and pursue several indications. But obviously, we would like to look at the data and then, with Sanofi, decide how to prioritize indications going forward. But I would say their decision is in global development, of we hope to be multiple indications. STAT3, outside of oncology. So we have been talking about this program for a couple of years. We've released data in different conferences. This is something we're very keen on. And I think we'll share some data as we firm up our clinical strategy around this asset. For now, this is something that Kymera is leading independently from any other existing or any potential new partner. But obviously, time will tell if things go in different ways.

This is Divya on for Mark. We have one on the oncology program and then one on KT-474. So just for the oncology programs, what data can we expect at the R&D Day? And then could you remind us what level of degradation you would expect to see to translate into clinical activity? And then for 474, with Part C now completed, I know that you guys are doing some analysis and that is still ongoing, but is there anything else data-wise that still needs to be generated before presenting the data package to Sanofi this quarter?

Sure. For both oncology programs, the aim is for us to be able to show what we call proof of mechanism, which is knockdown of the intended targets to a level that hopefully is associated with preclinically antitumor activity and to show that we can accomplish that knockdown at doses that are safe and well tolerated. Your question around what are the target levels of knockdown for the various programs. For the IRAKIMiD program, we've seen that knockdown of IRAK4 in the IMiD substrates, Ikaros and Aiolos in the 60% to 80% range is sufficient to give us activity in MYD88-mutated DLBCL. So that's a level of knockdown that, ultimately, we'd like to see in that program. For STAT3, we've shown in STAT3-dependent lymphomas that greater than 90% knockdown maintained for several days is sufficient to also induce significant tumor regressions in that context. So those are the sort of benchmarks that we'd like to ultimately see. But from the standpoint of what we'll be presenting at R&D Day, our hope will be that we'll be through enough dose levels to be able to show initial proof of mechanism at doses that are safe and well tolerated.

And maybe I'll take the other question. First, thanks, Jared. On 474, I just want to maybe take the opportunity to remind what the purpose of the study was and is. And it's really to demonstrate that transitioning from healthy volunteers to patients, we were able to maintain a good both PD, PK/PD relationship and safety profile to advance the drug into Phase II. And so that means that our key goal is to actually collect data to demonstrate that there is a continues to be a strong relationship between exposure and PD that can inform our Phase II dose selection, that the PD has now defined, let's say, a direct degradation in blood and skin that PD results in impact on disease-relevant, pathway-relevant chemokines or cytokines that we believe will create that new now correlation, given that in healthy volunteers we weren't able to do that. So correlation between, let's say, target engagement and something that is disease-relevant as the biomarker. And then, as we said, just so that I obviously don't dismiss it completely, we've also said that we will be collecting clinical endpoints with the goal of trying to establish a potential correlation again with some PD, some biomarkers or anything that can be tied to clinical endpoints that obviously would be highly exploratory given the size and the design of the study. Now going back to your question, sorry, we are actually still collecting data. So there is some data that you can imagine is easily accessible in an open-label study. And then there is some data, especially with regards to PD, that actually takes weeks to generate. So we are generating data. We're not just analyzing data. And so it would take us more time to fully collect all the data. And that's the only reason for having a December call, because we wanted to have the totality of the data in hand before sharing it, again, both with Sanofi to get their approval to share the data and then with all of you.

It's Eric Joseph from JPMorgan. Nello, I'm assuming that some of the additional data you're gathering is perhaps the intermittent dosing data in healthy volunteers. I know you added this additional cohort looking at biweekly or every-other-day dosing. Is that specifically the data that you're gathering? And I guess, should we expect those data to be presented at December 14? And then, I guess, can you just talk about the rationale for evaluating that regimen specifically with 474?

Thanks, Eric, for bringing that up, actually. So the answer to your first question is no. I mean, we're focused on the patient cohort. And as I said, just maybe to be even more transparent, in this study you can get initial read on safety and clinical endpoint quickly. There are obviously data lock and cleanup that take time even to do that. And what is taking longer, as it does and as it has done in the past, is generating all the PD and biomarker data. These are not simple assays. In fact, these are cutting-edge things that we're doing in the industry. I don't believe other companies have ever done what we're doing in HS and AD patients. And I have to thank Jared and his team for all the work that they've done in actually designing and executing and hopefully eventually generating the data. With regards to the infrequent dosing, as I've said in the past, this was a PK/PD experiment that we wanted to run before the eventual transition of the program to Sanofi, where we will lose the ability to run clinical studies. And this was a study that we wanted to learn not just for KT-474 learning, given that in the SAD we learned that has extended degradation after a single dose. So we wanted to learn how far and how reliable it would be dosing less frequently. But also for us, it was a big platform question. But I don't expect that that will be part of our disclosure. I think we'll be focused on unless there is anything relevant to the development of the program but we'll be focused on the patient data and how hopefully that will be informing further development.

Okay, great. I appreciate that. Maybe just a follow-up, if I could, on the oncology programs. And thanks for sort of setting...

We can't hear.

Excuse me. Just a follow-up on the oncology programs and thanks for framing expectations into December 14. I'm just wondering whether as part of the presentation you might be at a point where you can detail recommended Phase II dose. Really, how close a line of sight do you have on when you might start enrolling the expansion cohorts for 333 and 413?

At this time, it may not be appropriate for us to comment in detail. We might provide more information in December. However, I want to emphasize that we are still in the dose escalation phase and are concentrating on it. To provide some context, the advantage of this technology and the reason many of us are involved is that it enables a different approach to drug development. It allows for data-driven drug development where, given the right design of clinical trials, you can determine your position relative to your expectations regarding the level of degradation necessary to achieve the desired efficacy. In the dose escalation, instead of blindly escalating to a maximum tolerated dose, we have the chance to escalate while assessing where we stand in relation to our expectations on the necessary degradation for efficacy. Our main goal this year is to evaluate whether the translation of pharmacokinetics and pharmacodynamics, as we have seen with KT-474, represents a reliable, predictable, and dose-responsive degradation of the protein along with the associated safety profile that aligns with preclinical data. If we can confirm this, it will significantly enhance our outlook on the clinical success of these drugs, particularly since the mechanisms in oncology are well understood. The key will be ensuring the pharmacodynamics and safety are correctly addressed for both drugs in oncology. Demonstrating this would represent a major de-risking milestone for the program moving forward. I appreciate your question, and while I cannot provide specific details now, I anticipate that next year we will continue to focus on both escalation and expansion, which we may discuss further in December.

Following up on KT-474, I just wanted to see if there had been any more exploratory work done on the palpitation and QTc signals that you reported earlier with the healthy volunteer dataset? And if so, if there's any update to communicate out here on anything more you might have learned versus your prior update on what the mechanistic rationale for these findings could be? And then secondly, on the same program, going back to your prepared remarks, you mentioned that you won't be seeing steady-state degradation until the second half of the dosing interval in Part C. So given that, how would you advise people to interpret the efficacy data here versus some other 28-day dermatology data sets that are available in this space?

Great. Thanks, Vikram. Maybe, Jared, if you want to comment on the first question. The only thing I will say maybe before passing it on to Jared, we have never drawn a line of correlation between palpitation and QT. But I'll let Jared comment on anything else that we want to share on our understanding of the mechanism on the QT at least.

Based on our previous discussions and the in vitro data, we have observed that iPSC cardiomyocytes demonstrate an effect on current that suggests a mild herd effect at high concentrations, which occurs with some delay. This aligns with our clinic findings, where the effect also appears delayed and is not dependent on dosage or exposure. It seems to plateau after Day 7 and remains steady until the dosing period concludes at 14 days. We do not have new information regarding the mechanistic understanding of these observations. In Part C, it will be crucial for us to monitor the QT effect as we extend our observations to 28 days of dosing, beyond the 14 days we assessed in Part B. This will help us determine whether the QT effect continues to plateau and offer insights into the potential clinical implications of the non-adverse QT effect we noted in Part B.

And maybe then to get back to you on the efficacy question, I mean, the question you asked is really why we continue to say that expecting clear efficacy readout from this study is, I think, kind of unfair for how we've designed the study and the purpose of the study. And it's really difficult for us kind of scientifically to take the eventual data set and compare it to other agents, given that this is a different mechanism, new pathway, small numbers, no placebo, and, again, for a new mechanism, relatively very short time. But I think what we want to be able to do, if possible and again we'll have to generate the data and see, is to see if there are any trends between what we see in terms of PD and biomarker changes, any early signs of differences in clinical endpoints. It would be really hard, if not impossible, for us to say that the drug works or doesn't work in HS and AD based on comparison with other studies, just because this is a different study.

On MDM2, maybe if you could just elaborate on what a potential initial trial design would look like and any commentary on data timeline, say, if we could, assuming IND clearance, see data next year. And then also just in terms of the biology, how you're thinking about what tumor types this would make the most sense in and be best suited for as you had planned on initial dose escalation and thinking about expansion cohorts that you might be looking at.

Thanks, Eli. I'm excited to talk about other programs in our pipeline, particularly MDM2. This program is important to us because it represents how our technology can achieve outcomes that others cannot. We hope that everyone understands that this has been our guiding principle for selecting targets. When we announce our next few programs, all of which are at an advanced preclinical stage, you will see this philosophy continue. With MDM2, we are not dealing with a very small molecule; instead, we're exploring a different biological intervention in that pathway, aiming to reproduce genetic data indicating that the absence of MDM2 leads to heightened sensitivity in p53 wild-type tumors, which is not the case with small molecule inhibitors. Our approach allows us to quickly eliminate the protein, break the feedback loop, and induce apoptosis in a manner that small molecules cannot achieve. I’ll let Jared share some insights on the clinical trial design, although we haven't disclosed everything yet, but he can provide a high-level overview. Our strategy is to concentrate on indications where we observe a swift apoptotic response, enhancing efficacy and safety for this mechanism. We have several indications in both liquid and solid tumors that exhibit this kind of response. Additionally, our ASH abstract was released today at 9:00 a.m., offering more details on AML, which is one of the indications we're particularly interested in. Jared, would you like to provide a brief overview?

Definitely. Just to give a high-level overview and just as a reminder that because of the unique mechanism of action of degrading as opposed to just small molecule inhibition, we're able to sort of dose intermittently. So we're planning on bringing in an intermittent IV dosing, so infrequent IV dosing, into the Phase I. And the trial design, it will be sort of a standard Phase Ia dose escalation, followed by a Phase Ib expansion. But importantly, the Phase Ia will be able to set us up to understand safety, tolerability, and PD both in heme malignancies as well as in solid tumors. And we will have opportunities to put on indications of particular interest, both in heme malignancies and solid tumors, within Phase Ia. And then eventually, once we do come up with a recommended Phase II dose or maximum tolerated dose to then bring that into a Phase Ib expansion, that will likely involve expansion then in malignancies, especially AML, but potentially others, including lymphoma, as well as in solid tumors.

This is Joe on for Geoff Meacham. On KT-253, are you hoping to achieve a tumor-agnostic label? And can you provide any additional information on patient selection and your breakdown between liquid and solid tumors?

Joe, that's a great question. We unfortunately are not in the position to comment on the specifics but rest assured that that is one of our ongoing translational works, being able to potentially get to that type of tumor-agnostic development and approval. But we're not in the position right now to comment on where we are. And this is something we hope to share at different meetings, hopefully next year. I know the team is working on, obviously, generating data and also identifying the right medical meetings to start to discuss what our translational strategy is.

Can you comment on what were the stopping rules in place for Part C? And can we rule out all Grade 3 or Grade 4 adverse effects? And also a follow-up question is that you mentioned earlier that you are still preparing data for Sanofi. Can you confirm that Sanofi hasn't seen any of the data yet and there was no piece-wise data or real-time safety data that they already saw when the study was ongoing?

What was the first part? Ah. So I think we've said it in the past, we can't really comment on the specifics. Obviously, if there were events that impacted the study's success, we would have had to share them. With regards to Sanofi, we really are not in the position to share what we have or haven't shared with them. But again, as I said earlier, you can assume that we're in constant communication, as we've been throughout the collaboration. So I'll leave it at that.

Just a couple from us. On KT-333, which is your STAT3 program, other than on-target degradation in the Phase I study, are there any other PD markers related to STAT3 that you're looking at that could potentially further validate this target?

Jared, do you want to take that one? Thanks, Michael.

Thanks for the question, Michael. So in addition to looking at STAT3, yes, we are also looking at the impact of STAT3 degradation on the actual STAT3 pathway. We'll have the best opportunity to look at that in serial tumor biopsies. We can look at the impact either looking at phospho-STAT3 or looking at gene expression profiles for STAT3 pathway activation. So that will give us an opportunity to show not only that we can hit the target but that by hitting the target we're able to impact the pathway itself. We'll also be doing genotyping of these patients in order to see whether specific genotypes, for example, STAT premutations or other mutations affecting the pathway, correlate at all with clinical responses as we get into higher doses when we can start to assess the clinical responses and where we can start to bring on the target patient population, especially those patients with T-cell malignancies.

So expect that to be part of a kind of our global assessment of a comprehensive Phase I study. Obviously, it's not something that we can do in every patient.

All right. Got it. And then a question on your MDM2 program. It sounds like you are focusing on AML and then perhaps other solid tumors as well. And I know with this class of drugs, there has been some on-target toxicity; in particular, myelosuppression. And I was just wondering with the degrader mechanism and I think you mentioned the intermittent dosing schedule that you're looking at, I guess just given the PK and PD around degradation, do you think you can avoid some of those safety issues that have been associated with some of the other drugs in the class?

To clarify, Michael, AML is one of the indications we're interested in, but it's not the main one. It's just one area where we have generated data and will be part of our clinical strategy. Regarding the second part of your question, my earlier point was that we aim to utilize protein degradation for effects that small molecules, antibodies, RNAis, or gene editing technologies cannot achieve. We seek to create a therapy that is safe and effective, significantly more so than other agents can provide. The key is to achieve a profound effect quickly, which small molecules struggle with, thereby allowing for recovery. As Jared noted, we administer doses infrequently, once every three weeks, which has proven effective in inducing rapid apoptosis in tumor cells while enabling healthy cells to recover since they are less sensitive to cancer cells. This approach allows us to manage safety while maximizing efficacy. Although not directly comparable, our strategy for developing IRAKIMiD and managing neutropenia with the IMiD aspect follows a similar philosophical approach. This is why we have designed our drugs for infrequent dosing, allowing for molecular-level adjustments that promote extended pharmacodynamics and recovery of non-cancer cells. At Kymera, we are not just advancing protein degradation in immunology; we are also demonstrating how thoughtful drug development can transform cancer biology, leveraging technology to shift the conventional thinking about influencing tumor biology.

A follow-up question regarding the efficacy rate out of 747. So how many lines of prior biologics actually allowed for the trial according to protocol? And do you expect most of the patients had a prior DUPIXENT or other treatment for AD and HS patients, respectively? And to further complicate the efficacy interpretation, besides the difference in PK/PD and also the other factors of 474 compared to any other AD and HS drugs.

Thanks for the question. We actually did not restrict the number or type of prior treatments for either AD or HS patients. So the Part C of the Phase I allowed patients either who had not received prior therapy or prior systemic therapy, as well as patients who had received prior therapy, including biologics. If patients had received any prior systemic therapies, they required a washout period before coming on to the study. So we did not allow concurrent therapy along with our degrader. That would have compounded the results. Again, because this is a small open-label study, we were not trying to control baseline characteristics in terms of prior treatment. That would have been difficult to do and probably not appropriate for such a small study. And because clinical efficacy is not the primary endpoint of Part C, we didn't feel it necessary to do that. However, when we do look at the results, we will of course pay attention to what the prior treatments of any were for patients with either AD or HS. And as we interpret results, especially exploratory endpoint results, we will certainly keep that in mind.

Thanks, Jared. To clarify, we are not expecting any impact from previous therapies because all patients who were on them will have been washed out. Therefore, there will be no prior drugs present when they receive KT-474.

Having completed the dosing portion in Part C, can you provide any details on the split between the total number of AD versus hidradenitis patients in the study and whether those baseline characteristics are largely consistent with your expectations?

Well, I mean, I think we're close enough to sharing the data at this point, we're just going to not comment on the split. I think baseline characteristics, Jared, we've always said moderate to severe, right? So I think that's consistent.

The first one, I was wondering if you can tell us more about the difference in terms of biology between HS and AD. And I guess on your December data set, would you be able to differentiate the potential in these 2 types of diseases and provide prioritization at that point? And then the second set of questions around the safety. Given you have been worried that the less frequent dosing schedule in your MAD study, can you comment on any change or any safety signal in terms of QT prolongation in that cohort? And finally, on that, also related to QT, can you confirm for your oncology program, STAT3 and also IRAKIMiD, that the QT prolongation signal should not be expected?

Thanks. So maybe I'll start from the last. And then maybe, Jared, if you can comment on the first and the HS and AD biology. So the last one is easy. We don't expect that QT has anything to do with the platform program, broadly. As we've shared already, we have characterized for KT-474 this weak signal that we believe is compounded by a higher-than-expected exposure in the cardiac tissues in humans that leads to this very atypical non-dose-responsive QT prolongation that, again, we believe has no impact, in our view, on clinical development of this drug, assuming it stays within the range that we've seen in healthy volunteers. We've also said in the past that we've been able to replicate this change of currents in cardiomyocytes, I believe Jared said it even earlier today, and we've also shared that in that particular assay we demonstrated that we can take another IRAK4 degrader and show that we don't change current. So we know it's a molecule-specific event. Going back to the infrequent dosing and safety, I mean, all we will say is that if there is anything out of the study that is worth sharing, we will share. I guess, as I've said it in the past, the reason why we've never discussed this study is because we had almost little or no expectation that it will have an impact on the development of KT-474. It will be informative, again, for the drug. It will be informative for the platform. Again, if there is data from the study that is worth sharing, we will share it in December. But I continue to advise, guide on low expectations there. And then on HS and AD, Jared, if you want to comment on the biology.

Sure. In terms of the biology, even though HS is classically thought of as a Th1/Th17 disease and AD is as a Th2 disease, in reality, there have been very interesting sort of gene expression analyses of skin lesions showing that the inflammation is actually quite mixed in both of these diseases. Even in AD, in addition to Th2, you see Th1 and Th17 elements. And in HS, you can also see some Th2 elements. In reality, both of these diseases, importantly, are driven by toll-like receptor activation. Bacterial colonization of the skin, which activates toll-like receptors, is important in both diseases. And both diseases have also been shown to be driven by multiple different IL-1 family cytokine members. And so there's probably more in common pathophysiologically between those diseases than one might suspect. And therefore, we think both of these diseases are really prime indications for targeting with an IRAK4 degrader.

Great. Thanks, Jared. So maybe just to conclude, thanks, everybody, for joining today. I want to say from myself and the whole team we appreciate the engagement from the community, from our analysts and investors. We've had, I don't know, hundreds of meetings this year. So we appreciate that there is interest in what we're doing. As you know, we're always available to follow up with many of you that are interested in understanding the facts and designs at Kymera. We're excited about what we're doing. I think that the sky is the limit for the technology and it's really our responsibility to develop drugs and to build the company that can really capitalize on the power of it. So we look forward to seeing you, hopefully, all of you in December and some of you maybe at conferences where we'll be present in the next few weeks.

This concludes today's conference call. You may now disconnect.