Hi everyone, my name is Maury Rycroft, and one of the biotech analysts at Jefferies. It's with great pleasure that I'd like to welcome Yujiro Hata, the CEO of IDEAYA Biosciences. Thanks so much for joining us today, Yujiro. We're going to do a fireside chat format. For those who may be new to the story, if you can give a one-minute intro to IDEAYA.
Thank you, Maury, for the introduction, and thank you to Jefferies for hosting us for this fireside chat again this year. IDEAYA Biosciences, we're a leading precision medicine oncology company. Our lead program, darovasertib, is in a registrational trial in the frontline metastatic uveal melanoma setting. We are guiding towards a randomized median PFS readout to hopefully enable our first accelerated approval filing in the U.S. here very shortly. We've guided towards year-end this year to Q1 next year. In addition, Maury, as you know, we have a very deep pipeline. We have eight clinical stage programs targeted to have nine by the end of the year. Probably the next two areas I would focus on is a leading clinical pipeline in MTAP deletion.
We have two key clinical assets here, one ID397, which is a phase II MAT2A inhibitor, also an MTAP-cooperative PRMT5 inhibitor, ID892, which is now in phase I clinical trials. In addition, we have a significant focus in the ADC arena. Here we have three clinical assets of note. We have a DLL3 topo ADC, which, as you know, we had a recent oral presentation at the World Cancer Lung Conference. We also have a bispecific B7-H3/ PTK7 ADC, which is now in phase I. We also have ID161, which is a PARG inhibitor, which we think could be a really terrific combination partner for the topo ADC class. I think that will be the one-minute summary.
Got it. Yeah, great summary. Covered a lot in one minute there. Maybe talk about the PFS readout that's coming up soon. Can you give us any perspective on how close you are to the PFS event threshold? Are events coming in slower than what you expected, and how should we interpret?
Yeah, so the PFS events are tracking on track. We need roughly 130 PFS events for the top line results. We will have first read on the investigator PFS events, and then trailing that will be based on central review. Once we have the sufficient events, we'll go through that data log process. We'll need several weeks for that analysis and then be able to provide that top line result summary. We are approaching that time point, but we still think we are going to be at least several weeks out, most likely into early next year type timeframe.
Got it. We have talked a lot in the past about just expectations for control arm versus the treatment arm. Does the current PFS rate increase your confidence in showing that approximate seven months PFS in the combo arm, or what are your latest thoughts on that?
Yeah, look, we feel good about the PFS results. As you know, Maury, in the control arm, we do anticipate it's going to be in that two- three month range. In the treatment arm, we've shown fairly consistent results. At ESMO, as you know, we had a seven-month PFS. We just had a recent update at the Society of Melanoma Research in Amsterdam and also demonstrated a seven-month PFS. We do hope it's going to land somewhere in that seven to eight-month range, which would enable us to at least have the potential to hit that SIG. We feel good about that. I would say the one part in terms of patient baseline characteristics, and we've noted this as part of the SMR update, which is around the ECOG performance status and the ratio of ECOG zero versus one.
At the SMR update, we did show 40% of patients had ECOG 1, where ECOG 0 percentage was 60%. Typically, in frontline studies, including the TEBI study, both in the treatment and control arm, it was about half of that was ECOG 1. I think if we see that type of patient baseline characteristics, we hope there could be an opportunity for further upside.
Got it. Okay. Based on what you just said, it sounds like the database is not yet locked yet for the study.
That's correct.
Okay. Realizing that there's going to be cleanup involved and a lot that you're going to learn once you see the data, what do you plan to disclose in the data update? Will you comment on how the OS curve is looking at that point?
Yeah, so we're still having that discussion internally. I would say at a high level, we'd like to be able to share as much as we can reasonably share. I think on the OS part, I think the question there will be, do we have sufficient number of OS events to make a comment there? If we do, and obviously we'll discuss it internally, I think we'll try to do our best to share as much information as we can.
Got it. Okay. Will it be a press release? You plan on holding a conference call for it?
Yeah, it's probably going to likely be both. Put out top line results in the form of a press release, and we'll likely host something as well to be able to walk through that information.
Got it. Maybe talk about next steps, and when do you think you'll be able to have a pre-NDA meeting with FDA, and when do you anticipate submitting the NDA?
Yeah, so we haven't gone through specific guidance around what would be the next steps after that. I think perhaps as we page forward into next year and as we get closer or we have the PFS results, we can give more visibility. Yeah, the steps there, Maury, as you can appreciate, will be when can we file the NDA, when do we anticipate the OS results, and obviously you'll be able to put that together, hopefully get a better sense of the timing of a potential launch.
Got it. You mentioned the SMR data. You showed OS data there that looked better than what people expected, and the curve was not fully mature yet too. Can you just provide a status update on the OS curve?
Yeah, so I think the data cutoff we had at SMR was approximately May of this year. That is roughly about six months ago now. We do know that there are several patients that were below the median that are continuing on study, at least from my last understanding from the clinical team. If those patients do continue through the end of the year, the median OS could bump up to 22 months. It obviously could go up further than that depending on how much further they go. I think really the big picture is we feel we have achieved our objective. At least our perspective is that we demonstrated a robust median survival result based on the study, and now the focus really shifts to the randomized trial.
Got it. Okay. A common question we get for this program is on pricing, particularly. In our model, we've gotten the low $50,000s, but I think some investors think it could be higher. How should investors think about this?
Yeah, look, for us, we think we have a price comp that's out there, Maury, as you know, which is an actual. I think that's good. Second, we think it's going to be about how robust the dataset is, including the PFS and obviously in the future OS results as well. As we know, this is an extreme high area of unmet medical need. Unfortunately, survival for these patients is extremely poor. When we're seeking frontline approval currently today, there's no approved therapies. Maury, we appreciate where the analysts are. As you noted, roughly in that $50,000+ range per month. We think we know those numbers are out there. We're just not prepared to provide comments beyond that at this point.
Got it. Okay. Based on what you're seeing in your phase II study, how long do you think the average duration of treatment is going to be?
In our clinical study, we are seeing patients being treated beyond progression. If you say roughly, let's say PFS that lands in that seven- to eight-month range, I would say historically we've been seeing patients getting treated roughly three months beyond progression.
Got it. Okay. For the planned publication of the HLA- positive data from the phase II study and the real-world evidence for standard of care treatment in HLA- positive patients, what can you tell us about timelines for the submissions of the manuscript? Can you walk us through the procedural steps for getting the NCCN guidelines updated?
Yeah, so in terms of publication strategies, our medical affairs group is hard at work in terms of planning what is the right publication strategy. We do anticipate we'll be quite active in 2026 as hopefully we have positive results on the randomized PFS data. Obviously then the HLA-A*02- positive setting and our compendia strategy becomes critical to that. Central to that strategy will be the publication plan. Just to table set folks, this is going to be roughly 70-plus patient worth of data that we've been enrolling in the A*02- positive setting. We will plan to publish that. In terms of the compendia process, roughly about a six-month process. This assumes we get approval in the frontline HLA-A*02- negative setting, and we'll go through that process with compendia.
I think overall, we feel our prospects should be very positive there, assuming we do get accelerated approval.
Got it. For the HLA- positive data, would you discuss that with FDA at your pre-NDA meeting?
The plan right now is to submit the A2- positive data. I'm talking about the single-arm A2- positive data to also see if there's an ability to get it on the label. Here, just so it's clear, that's not base case. Base case we're communicating is through compendia. We are going to go through a real-world evidence process where the FDA share our A2- positive data and see if we can get that also on the label. We appreciate that it's unlikely to be in the frontline setting, but we'll go through that process assuming, again, we hit stat SIG on PFS. The plan is to submit that data as part of that broader NDA submission.
Got it. I think investors appreciate that patients who are on TEBI, once they progress, they would likely go on Dara. I guess just what are the implications of potentially getting that HLA-A*02- positive in the compendia listing or label? Just how do you look?
Yeah, I think the main distinction there is going to be around your ability to promote as it relates to the A2- positive. Obviously, if we get it on compendia, it would give us the ability to, in terms of pricing and reimbursement. I should have mentioned there, Maury, I think in addition to the compendia part, one other area that we're thinking through is do we even have any delineation on A2- negative and positive for compendia? We just keep it generally metastatic uveal melanoma, because again, we know that the agent works there, which would obviously enable a situation where you do not actually need to get screening, right? You can just treat those patients and get reimbursed.
Got it. Okay. Interesting. You are also expanding into the neoadjuvant setting as well. Can you talk about how enrollment's going so far for the pivotal study? Do you see a potential path to complete enrollment by end of next year? Could the partnership with Servier help speed up enrollment?
Yeah, so for the neoadjuvant setting, as you know, we did reduce the patient number down by about 70 patients from 400. I think that's good. We are increasing the number of sites pretty substantially. We were roughly in 20 sites in the phase II study, and we're increasing that by approximately five times. We did enroll roughly 100 patients in about a year, maybe a little bit more with 20 sites. Obviously, 5Xing that, we would hopefully be able to have much more rapid enrollment. I think right now what we're guiding towards is in approximately five quarters plus or minus. We're going to do our best to enroll that study. Right now, we are in the process of site activation. Multiple sites have been activated. Multiple patients are currently in screening. We're going to go as fast as we can.
Got it. Okay. You had an update from your phase II program at ESMO 2025, and you showed an average of plus 14 mean BCVA letters in the neoadjuvant patients prior to plaque brachytherapy or enucleation. Will your phase II dataset be mature enough to show de-risking BCVA 15 data in 2026?
You're talking about post plaque therapy? Yeah. I would say that we'll continue to track that data. I think the post plaque therapy BCVA actual vision test information is going to take more time to mature. I think we will likely have a portion of that, proportion of that data next year. Whether that will be in time to be able to share that information, we'll see. If it is, absolutely, I would hope that our team would plan to put that out there. I think the question will be, is it will be sufficiently mature at that time.
Got it. Okay. Your pivotal, it's got 90% power for 20% reduction in loss of 15 BCVA letters versus placebo. Did you factor in the BCVA letter gain prior to primary treatment with plaque brachytherapy into your treatment effect assumption, or does that gain provide additional buffer that further improves the OS?
Yeah, so I would say it's the latter. Hopefully that additional vision gain that we are seeing, the data has been evolving real time. Obviously, we saw almost a doubling in that BCVA letter vision gain from the data that we presented at our R&D day in New York City just in September, and then that with a larger denominator, more patient follow-up. Yeah, I will look at that as hopefully being able to provide more buffer going into that primary endpoint readout for that cohort.
Got it. For the control arm assumptions for neoadjuvant, can you just remind us what you used for that? I guess was that the comms study for that?
Correct. Yeah.
Okay. Got it. For the adjuvant program, you're planning to start that in the first half of next year with Servier. Can you talk about your latest thinking for the design of that study in terms of number of patients and amount of follow-up on RFS? When do you plan to meet with FDA to finalize the protocol?
Yeah, so we're still in collaboration with our partner Servier around what a phase III adjuvant study can look like. Here, I'll just kind of talk about it at a high level. It will likely be in the high metastatic risk population, high medium metastatic risk population. It will likely be in that 400 patient-450 patient number to ensure we have sufficient powering. In terms of the primary endpoint, I think as you would think of for typically an adjuvant trial, ideally you show some superiority as it relates to relapse-free survival.
Got it. Could we potentially see RFS data from the phase II study to help the URSS program next year?
In terms of for the neoadjuvant study, we're collecting EFS data. There is an adjuvant portion. I would just say we're transitioning away from that to focus on the actual randomized phase III adjuvant study specifically for RFS. Sorry, Maury, I should have mentioned that adjuvant trial, just as a reminder here, we would be randomizing against placebo.
Got it. Okay. Okay. Let's shift gears to the ADC programs starting with DLL3. You've shown some positive data from this program, and you talked about a second-line monotherapy accelerated approval pathway. Can you talk about how you're thinking about a potential path to a pivotal study and how that might differ versus Xylab second-line pivotal strategy?
Yeah. In terms of pivotal trials, there are really two that we are focused on. We are not prepared to give all of the specifics and details, but I will kind of break it down at a high level. One is what is going to be our pivotal study as it relates to a monotherapy accelerated approval study. We do believe based on the monotherapy activity that we are seeing that there should be some path available to us. Here, the question will be what is the indication. Obviously for DLL3, small cell lung cancer is a consideration. Neuroendocrine tumors as well is a consideration. Of course, what line that you potentially decide to pursue that. That is the first one. Hopefully we will be able to provide more color on that here relatively in the near term. The second study will be in small cell.
I would say probably our most significant focus in small cell is in the frontline setting. There are several moving pieces, as we know, in small cell, in particular in the frontline setting with agents such as InDelta. We are carefully thinking through that, but we are, I would say, getting closer to making a decision on what that strategy will be moving forward. The last part I will mention is ideally we'd like to also just generate key combination data with some of the key components, including chemo, including checkpoint inhibitors. As you know, we have a proprietary asset in PARG. We feel with that information, with our understanding of how the competitive landscape is evolving, we'll be able to launch into hopefully a very sensible frontline study in small cell lung cancer in the future. At least that's the plan and goal.
Got it. Could we see additional data from Hungary's small cell lung cancer dataset sometime next year?
Yeah. I would say that for that next dataset, I would hope we can provide our data from the U.S. and other parts of the world from the IDEAYA sponsored study. In addition, I think we've noted at our last earnings release that we are also seeing monotherapy activity in the neuroendocrine tumor space. I think that's a possibility in terms of Hungary and that type of data that gets hopefully shared in a medical conference setting in the future. We have not specifically provided guidance on that, but I think those will be the next two datasets. Lastly, I would mention we are targeting to do the DLL3 PARC ID161 combo dosing by the end of this year. I think that would be also hopefully a high-value dataset that we would like to target sometime in the near medium term.
Got it. Yeah, for the combo, you'll start the PARG combo by the end of this year. I guess for the other combos, maybe just talk about the timelines there and what you want to see in order to have a data update.
I think for the other agents, I think our sense is we're going to want to parallel track as much as we can as it relates to some of these standard of care agents for all the reasons we talked about, because that will enable us more quickly to be in a position to launch that frontline study.
Got it. Is there an expectation for what you want to see for the PARG, excuse me, PARG combo on efficacy and safety?
Yeah, look, I think unfortunately for these patients that we're treating in the small cell and neuroendocrine tumor space, it's really all about durability, right? Even with relatively high responses, including for standard of care, unfortunately these patients' median outputs, including PFS, OS, is not great. We think that's really where we hope this PARG combination could enhance durability and we can really deliver on that piece. Because if we can, then we think we're extremely uniquely positioned in the market.
Got it. Okay. Maybe for DLL3, maybe just talk about the safety data from the World Lung Update and how that looks based on doses.
Yeah, look, we think the data that was shared at the World Cancer Lung Conference is exactly what you typically see from typical ADCs. At the 2.4 mg/ kg expansion dose, which is going to be definitely one of the doses we'll be looking at very carefully, we feel we've seen a very favorable AE profile where the grade three or higher AE rates, which has been largely blood-related AEs. Here, it's less than 20%, at least as the data cut off. We believe we actually have some room to go up. As you know, Maury, many very well-known and approved ADCs, you see grade three or higher rates that are in the 30%-40% plus range. We do feel we have the ability to go up.
Whether we do or not is going to, we think, largely depend on how much more efficacy we can gain through that, in particular related to durability.
Got it. Okay. For your MAT2A program, you plan to show Trodalvy combo data in urothelial carcinoma at a medical conference in the first half of 2026. How are you setting expectations for that event? In 2026, do you plan on providing a plan on path forward for that setting?
Yeah, so there's going to be, we have our current guidance is a Trodalvy ID397 MAT2A update and MTAP deletion. I think in the first half, which is our current guidance, most likely will be urothelial cancer. The lung cancer data is trailing. We've dosed several patients. We have many patients on queue now. If we have sufficient follow-up, we'll include it in that first half update, or we may separate the lung cancer in a second half medical conference update. I think that's still an evolving story, but that's our current thinking on that. In terms of after that, once you've selected an expansion dose, and here, ideally, we've sort of built out what I described to you, sort of 20 patients-30 patients at an expansion dose, ideally in both tumor types.
That should put us in a position to make a decision on a registrational path forward. In parallel, as you know here, Maury, we do have an MTAP-cooperative PRMT5 inhibitor that's in phase I. We'll be getting that dosing moving here very shortly. Obviously, depending on what those results as well, will also impact our thinking. We also have other strategies in place, including around co-alteration. We'll hopefully compile these various datasets and make the best decision moving forward.
Got it. You'll get a lot of information in 2026 from these different programs that'll inform next steps.
Correct.
For the PRMT5 program, there's been a couple of data updates in the space. I guess just how do you see differentiation and positioning with that one?
Look, I think for us, there are several things about MTAP deletion we're excited about. One, as you know, Maury, it's a very high immense need. It's relevant to multiple solid tumor populations. There's nothing approved in the MTAP deletion space. In our perspective, to directly answer your question, we believe in this area, it's going to be about who enables the right combinations and the right clinical settings first. Second, as part of that strategy, who owns the key components? Because we think that's ultimately what's going to drive the greatest value, of course, to patients, but also in terms of shareholder value. That's really our focus. We have seen monotherapy activity across several of these targets. I think the good news is we do think this pathway has been validated.
I think the hard work begins with a lot of these combinations that are now beginning.
Got it. Okay. You have got a lot of other pipeline programs we could talk about. One that comes up is the CAT67. We are going to be filing your IND by year end 2025. Maybe talk about the clinical strategy there. Can you just comment on the mechanism and how targeting six/seven could have advantages versus just six?
Yeah, look, this area of CAT6, now CAT67, that we are pioneering with a first-in-class dual inhibitor of both CAT6 and CAT7. I think we know now this pathway has been validated clinically by Pfizer. They have presented data in multiple forums for just a refresher for folks with in combination with fivestrin, right? They saw a median duration response that was longer than a year. Clearly seeing exciting durability. We think there is an opportunity to take that target of CAT6 and expand it further, both in terms of tumor type indications, which, as you know, today has been largely focused on breast cancer, and to also expand it to other indications like lung cancer. We will likely consider certain combinations, but we also think there should be hopefully expanded opportunity for monotherapy activity as well. I think definitely a very exciting field.
Obviously breast cancer continues to be a major focus area for the industry. We think this is going to be a very unique asset in that area.
Got it. We are pretty much out of time. I feel like the wheels are already in motion for Dara with kind of the clinical development plan there. Maybe if you could talk about another key favorite program that you're interested in and just key catalysts ahead that investors should be focused on through 2026.
Yeah, look, I think after Dara, in terms of in my mind, the question is what's the next program you could get into a registrational study? Because of the type of monotherapy confirmed response rate we're seeing with our DLL3 typical ADC, and because of how high of a met need both the small cell and the neuroendocrine tumor spaces, I think that's going to be hopefully the next asset we can push forward and get towards a registrational type study. We appreciate it's competitive. We're going to move as quickly as we can, but most importantly, effectuate hopefully a clinical strategy that really delivers strong activity and addresses a high immense need.
Got it. Okay. Any other key events you want to highlight for investors?
No, I think Maury, you did a terrific job covering. I know we covered a lot of ground and great seeing you again in London. Thank you again.
Great seeing you as well. Thanks for joining us.