Good day, everyone, and welcome to the pivotal AUGMENT-101 top line revumenib data conference call. Today's call is being recorded. At this time, I would like to turn the call over to Sharon Klahre, Head of Investor Relations at Syndax Pharmaceuticals.
Thank you, operator. Welcome, and thank you all for joining us today. I'm Sharon Klahre, and with me this morning to provide a review of top-line results from the pivotal AUGMENT-101 trial of revumenib in relapsed/refractory adult and pediatric patients with KMT2Ar acute leukemia, are Michael Metzger, Chief Executive Officer, Dr. Neil Gallagher, President and Head of R&D. Also joining us on the call today for the question-and-answer session are Dr. Peter Ordentlich, Chief Scientific Officer, Dr. Anjali Ganguli, Chief Business Officer, and Keith Goldan, Chief Financial Officer. This morning, we issued a press release and reported top-line data for the pivotal AUGMENT-101 trial of revumenib in relapsed and refractory KMT2Ar acute leukemia, which can be found on the investor page of Syndax's website. Please turn to our forward-looking statement disclosure on slide two.
Before we begin, I'd like to remind you that any statements made during this call that are not historical are considered to be forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. Actual results may differ materially from those indicated by these statements as a result of various important factors, including those assessed in the risk factors section in the company's most recent quarterly report on Form 10-Q, as well as other reports filed with the SEC. Any forward-looking statements made on this call represent our views as of today, October 2nd, 2023, only. A replay of this call will be available on the company's website, www.syndax.com, following its completion. And with that, I am pleased to turn it over to Michael Metzger, Chief Executive Officer of Syndax.
Thank you, Sharon, and thank you all for joining us on the webcast. This morning, we are thrilled to announce top-line data from the pooled analysis of pivotal AUGMENT-101 trial of revumenib, our highly selective menin inhibitor in adult and pediatric patients with relapsed/refractory KMT2A-rearranged AML and ALL. The Independent Data Monitoring Committee, or IDMC, reviewed the data and recommended the trial stop early for efficacy in accordance with a protocol-defined interim analysis after achieving its primary endpoint with a CR/CRh rate of 23% in the evaluable efficacy population. Furthermore, the overall response rate was 63%, exceeding our expectations. We are excited to be one step closer to bringing revumenib to patients with KMT2A acute leukemia, a population for whom there are no approved therapies and who could meaningfully benefit from revumenib if approved.
The pivotal data we are presenting today continues to support revumenib's potential as a first and best-in-class agent. Slide three highlights the key aspects of revumenib's clinical profile on which treating physicians are most focused. As mentioned, the majority of patients achieved a clinically significant response to treatment, with high overall response rates in the pooled population, as well as the AML population. Notably, a high proportion of these patients proceeded to potentially curative transplant, much higher than the current benchmarks for patients with relapse and refractory KMT2A rearrangements. And following transplant, many restarted revumenib at its maintenance therapy. Several patients remained on therapy in the post-transplant setting, some for several months. The ability to offer relapsed and refractory KMT2A patients the opportunity to proceed to potentially curative transplant signifies an important paradigm shift in how these patients can be treated.
The historic rate of transplant for these patients is less than 5%, while revumenib has consistently enabled approximately 40% or more of KMT2A patients to proceed to bone marrow transplant. Importantly, revumenib continues to be well-tolerated, which we believe supports its use not only as a monotherapy and maintenance treatment in the relapsed refractory setting, but also its potential to be used in frontline standard of care combinations for which initial data is forthcoming later this year. Revumenib's potential advantage of having the only age and disease-agnostic label in KMT2A acute leukemia sets the stage for first-mover advantage to significant market opportunities.
With this positive data now in hand, we expect to submit an NDA filing for revumenib for the treatment of relapsed/refractory KMT2A acute leukemia by the end of 2023 and become a commercial-stage company with potential approvals and launches of both revumenib and axatilimab in 2024. Just to remind you, axatilimab is our anti-CSF-1R antibody for which we presented positive top-line data in July, and we expect to complete a BLA filing with our partner, Incyte, by year-end for the treatment of chronic graft-versus-host disease following two or more prior lines of therapy. Before I turn the call over to Neil, let me explain why we think revumenib has the potential to change the treatment paradigm in patients with KMT2A and NPM1 acute leukemia.
As described on slide four, there are currently no FDA-approved therapies targeting KMT2A or NPM1 acute leukemias, a population that together represents up to 40% of AML patients. With today's announcement, I'll focus on KMT2A acute leukemia. KMT2A acute leukemia represents approximately 10% of AML and ALL, and this diagnosis is predictive of poor prognosis. Historically, a third-line patient with KMT2A acute leukemia is expected to have, at best, a 10% response to standard of care treatment. Fewer than 5% of these patients receive potentially life-saving transplants, and life expectancy is less than three months. Today's data, demonstrating a 63% overall response rate and significant numbers of patients receiving stem cell transplant, followed by revumenib in the post-transplant maintenance setting, is why we believe revumenib has the potential to change the treatment paradigm for patients and their physicians. I will now ask Neil to walk us through the pivotal AUGMENT-101 top-line trial results. Neil?
Thank you, Michael. I am very excited to be able to provide a top-line overview of the results from AUGMENT-101, and to have an opportunity to be involved with a program that has the potential to make a significant difference in the lives of patients with acute leukemia. Revumenib is a first-in-class, highly selective menin inhibitor. In the schematic on slide five, you see the binding of menin to KMT2A, whether it retains its wild-type C terminus, as with mutant NPM1 AML, or has acquired a novel C terminus, as in KMT2A- rearranged leukemia, leads to transcriptional activation of leukemogenic genes such as HOX and MEIS1. Revumenib inhibits the interaction of menin and KMT2A, which suppresses the transcription of these leukemogenic genes, leading to differentiation and apoptosis of tumor cells, and consequently, clinical remission.
The Phase II portion of AUGMENT-101 was originally designed as three single-arm pivotal trials that independently enroll distinct patient populations: KMT2A- rearranged ALL, KMT2A- rearranged AML, and NPM1 mutant AML. Up to 64 adult patients could be enrolled in each of the cohorts, with the potential to enroll an additional 20 pediatric patients in each. Last fall, we shared the results of the revumenib Phase I trial in relapsed and refractory patients with KMT2A acute leukemia with the FDA, and later at ASH. After reviewing the data, the agency agreed that the interaction of KMT2A fusion proteins with menin is a critical driver of the leukemic transcription program in both KMT2A, ALL, and AML, and that the Phase I data demonstrated revumenib's potential to provide substantial improvement over available therapies across both populations.
Following the review, the agency granted breakthrough therapy designation for revumenib, covering all KMT2A- rearranged acute leukemia patients, agnostic of age and leukemic presentation. The granting of BTD gave us the opportunity to work collaboratively with the FDA to update the trial in order to deliver revumenib to patients as rapidly as possible. We reached an agreement that both KMT2A, AML, and ALL cohorts would be pooled into a single analysis, which could support a comprehensive indication for the use of revumenib for the treatment of adult and pediatric relapsed and refractory acute leukemia patients with a KMT2A rearrangement. The trial was designed to rule out the null hypothesis that the median CR/CRh rate would not be expected to exceed 10%. Secondary endpoints included durability of CR/CRh, transfusion independence, overall survival, and safety.
Patients who undergo transplant in the trial have the opportunity to initiate maintenance therapy with revumenib. This is an important option for patients, given that they are at high risk of relapse. Turning now to slide seven, the dataset we are reporting today is derived from the patients enrolled in both AML and ALL KMT2A cohorts. The updated protocol had pre-specified the number of KMT2A patients that would define the efficacy-evaluable population for the pooled interim analysis. The protocol also specified that once those patients enrolled into the trial, they would be followed for six months before database lock. As we previously announced, the 57th efficacy-evaluable patient needed for the interim analysis was enrolled in the first quarter of this year. While those 57 patients were in the six-month follow-up phase, the trial continued to accrue.
Any additional patients treated in either of the pivotal KMT2A cohorts prior to the July database lock have been, have been included in the safety population. The pooled KMT2A safety population includes 94 patients, and the pooled efficacy evaluable population includes 57 patients. Recently, the Independent Data Monitoring Committee met to review the data from the interim analysis and recommended stopping the trial for efficacy as pre-specified in the protocol. Based on the IDMC recommendation, the company is closing the trial to further accrual in the KMT2A cohorts. The NPM1 mutant AML cohort is ongoing, and we expect completion of enrollment by year-end 2023, with data available in 2024. Slide eight includes the baseline characteristics of both the efficacy and safety populations. The median age was approximately 35 years and primarily comprised AML patients.
It is important to note that over half of the patients had relapsed following treatment with at least one salvage regimen prior to enrollment, including nearly half, 46%, who had undergone prior stem cell transplant, reflecting the heavily pretreated stage of disease in this population. Patients had received a median of two prior lines of therapy. In this analysis, prior therapy was assessed according to the AML treatment guidelines for industry that the FDA published last October. The guidance defined for the first time how prior therapy should be assessed, including the recommendation that induction and consolidation therapy, followed by transplant, be considered a single line of therapy. Turning now to slide nine, the Phase II data further established that revumenib is an effective treatment for relapsed and refractory KMT2A acute leukemia. The trial met its primary endpoint with a CR/CRh rate of 23% .
As you can see, the confidence interval of 12.7%-35.8% rules out the null hypothesis of 10% with a p-value of 0.0036. More than 2/3 of patients who achieved a CR or a CRh had no measurable residual disease. The overall rate of response in this population was 63%. Patients were transplanted early in the course of treatment, and a notable proportion of patients received maintenance therapy with revumenib following transplant. The response rates observed in the KMT2A AML subpopulation were consistent with those in the overall efficacy evaluable population. Overall, 65% of AML patients achieved a response, and 24.5% achieved a CR/CRh.
At the time of the data cut-off, the median duration of CR/CRh response was 6.4 months in both the efficacy evaluable and AML populations, with 46% or six patients remaining in response. The data will continue to mature over time, and the duration of response may extend beyond 6.4 months with additional follow-up. As I mentioned a few moments ago, not only did we observe a high overall response rate of 63%, 39% of responding patients proceeded to transplant. Also of note, on slide 10, eight patients were transplanted prior to achieving CR or CRh at the discretion of the attending physician. Clearly, if physicians had decided to wait a little longer prior to transplant, then more of these eight patients could have achieved the best response of CR/CRh.
I mean, for example, if all eight of these patients had achieved CR/CRh, then the rate would have been 37%. Another important facet of the data summarized in the slide is the high proportion of patients, 71%, who either proceeded to post-transplant maintenance or who remained eligible for maintenance. As of the data cut-off, seven of the 14 patients who've been transplanted received maintenance, including some who have commenced their 8th cycle. Three additional patients remain within the post-transplant window and may choose to initiate maintenance. Similar to what we've previously shared at the European Hematology Association Congress, heavily pretreated acute leukemia patients in the Compassionate Use Program initiated revumenib as post-transplant maintenance and stayed on therapy for extended periods of time, in some cases, almost a year. We look forward to being able to provide longer-term follow-up for these patients.
Based on the clinical profile of revumenib, we believe that it has the potential to change the current treatment paradigm by enabling physicians to aggressively treat KMT2A acute leukemia. Slide 11 contains a summary of the data from the safety population that I described earlier. The safety profile of revumenib that was observed in the pivotal stage of AUGMENT-101 is generally consistent with what has been previously reported. Revumenib was well tolerated in this highly refractory population, and of note, only 6% of patients discontinued therapy as a result of treatment-related adverse events. The TRAEs of any grade and greater than 20% of patients included nausea, differentiation syndrome, and QT prolongation. At 23% of QT prolongation, I beg your pardon.
At 23%, the rate of QT prolongation of any grade was less than half of what was previously reported in the Phase I data set. While the rate of Grade 3 of 14% is consistent with previously reported data. As before, there were no Grade 4 or 5 events, and no patients discontinued as a result of a QT prolongation. The rate of differentiation syndrome observed was consistent with previous report, previous reports, and only one case of Grade 4 DS. All other cases were grade three or less. No patients discontinued as a result of of DS. In summary, we are extremely pleased with the data that we've released today. In this pivotal, pivotal phase II analysis, revumenib has again demonstrated robust efficacy and a well-tolerated safety profile in a heavily pretreated acute leukemia population. With that, I would like to turn the call back to Michael.
Thank you, Neil. As you know, Syndax has designed impactful trials that position revumenib for use in earlier settings with acute leukemia, including combinations with approved therapies, as outlined on slide 12. We believe there is significant market opportunity in the frontline setting, and based on the data generated to date, we anticipate revumenib will provide meaningful benefit across the acute leukemia landscape. Let me take a minute to remind everyone of a few of the other trials that we have ongoing. In the BEAT AML trial, revumenib is being combined with venetoclax and azacitidine to treat newly diagnosed AML patients who are unfit for induction chemotherapy as part of our collaboration with Leukemia and Lymphoma Society. Enrollment is ongoing, and we continue to expect data on safety at a potential RP2D from the trial by the year end, 2023.
AUGMENT-102 trial is designed to assess the safety of revumenib in combination with standard salvage chemotherapies for patients with relapsed or refractory acute leukemias. We expect to provide an update on the initial safety data and potential RP2D from the trial by year-end 2023. The SAVE trial is an interesting combination trial of an all-oral regimen, revumenib with venetoclax and Inqovi, an oral hypomethylating agent in relapsed refractory acute leukemia, being led by Dr. Issa at the MD Anderson Cancer Center. We also plan to initiate a trial of revumenib in combination with standard-of-care intensive chemotherapy, known as 7+3, in newly diagnosed patients with acute leukemia by year-end 2023. This trial will include an option for maintenance with revumenib monotherapy.
We are highly encouraged by data being generated with clinically active doses of revumenib in combination with standard of care agents, and we look forward to sharing that data later this year. Turning now to slide 13. The data we've shown today positions revumenib with a best-in-class profile for relapsed refractory KMT2A and further de-risks NPM1 as the next indication. Revumenib is on track to own the largest addressable population in relapse and refractory acute leukemia, which represents approximately 6,000 patients. These patients, together with their time on therapy, are what build this to a significant market opportunity. As with other indications, moving into earlier lines of treatment opens additional avenues for revumenib to benefit more patients and hopefully improve the overall course of their disease.
We believe that revumenib could become the backbone of treatment for acute leukemia patients with KMT2A rearranged and NPM1 mutant acute leukemias, and realizing that potential could bring significant additional value to the franchise. As you move into earlier lines, you not only access more patients, but they also have a greater chance of achieving a deeper and potentially more durable response to therapy. You can see from this chart that the opportunity for revumenib could grow substantially as we look to take advantage of our first-to-market position and quickly add frontline indications to our initial relapse/ refractory approvals for KMT2A and NPM1. Turning to slide 14, I'd like to briefly summarize why we believe revumenib is positioned to be a blockbuster in acute leukemia.
Through our conversations with leading investigators, as well as our market research among treating physicians, we have come to understand that across the board, physicians are excited about the efficacy, tolerability, and overall utility observed with revumenib in KMT2A rearranged and mutant NPM1 acute leukemias. Approximately 250 patients have been dosed with revumenib in AUGMENT-101, and revumenib has shown an ability to provide deep, durable responses for heavily pretreated patients as a monotherapy agent. It is both safe and well-tolerated, and the overall experience across ongoing studies supports use in combination with standard of care treatments. Based on our discussions, physicians believe revumenib enables their relapsed and refractory KMT2A patients to achieve remissions, go on to receive stem cell transplant, and follow up with bone marrow maintenance, with higher rates of success than experienced before in this patient population.
Revumenib's oral route of administration allows for at-home administration, and the availability of both a tablet and liquid formulation makes revumenib broadly accessible across pediatric and adult patients. Turning to slide 15, we have quite a few meaningful upcoming milestones for the revumenib program on the horizon for the remainder of 2023. These include presenting the full AUGMENT-101 results at an upcoming medical meeting, filing an NDA submission for year-end 2023, initiating a combination trial with intensive chemotherapy or 7+3, presenting data from the additional ongoing revumenib studies in combination with ven and chemotherapy, completing enrollment of the NPM1 cohort, and continuing to prepare ourselves for a potential commercial launch of KMT2A next year.
On slide 16, we would like to point out that we are making excellent progress executing on our milestones and corporate priorities, all of which has put us on a path to becoming a commercial-stage biopharmaceutical company with potentially two best-in-class products. Syndax is in the enviable position of bringing two practice-changing novel agents through development to the verge of NDA, FDA filings, and we've been able to accomplish this in approximately four years from IND. This presentation marks the second positive pivotal dataset we are reporting on in the last few months. The first was the AGAVE-201 data of axatilimab in chronic graft-versus-host disease, and now AUGMENT-101 data of revumenib for relapsed or refractory KMT2A acute leukemia. And we look forward to presenting the full dataset from both programs at future medical meetings.
Before we turn it over to Q&A for questions, I would like to take a moment to extend our gratitude to the patients, their families, the investigators, and the entire staff who participated in AUGMENT-101, as well as earlier and ongoing revumenib trials. We would not be at this exciting juncture today without your valuable contributions and help to drive innovation forward. Additionally, I would like to thank the teams at Syndax for all of their hard work and incredible collaboration, which made this trial and the positive data readout possible. And with that, I would like to open the call for questions. Operator?
To join the queue to ask a question, please press star five on your telephone. Again, that's star five on your telephone to ask a question. I will pause a moment to let the queue populate. Our first question comes from Anupam Rama from J.P. Morgan.
Hey, guys! Thanks so much for taking the question, and congrats on the data. Quick one from me. The 50% of patients who received revu post transplant maintenance, what was the deciding factor in terms of, you know, starting a maintenance therapy versus not? And maybe should we be expecting a full some data update at maybe ASH? Thanks so much.
Yeah, Anupam, thank you. Thank you for your question. So so look, I think the deciding factor here for physicians, as we understand it from them, is that this KMT2A population is one where they're a little bit younger in their course of... in their age, they're in their 30s, and the the treatment paradigm is that you want to take these patients as quickly as you can to transplant. So there's a drive to get them to transplant. The overall response rate, as we've reported today, was, you know, in the mid-60s%, which is an overwhelmingly good result, and they're clearing their blast. So they take them as quickly as you can to transplant, and we're seeing that.
We saw that in the Phase I, we're seeing that in the Phase II, and it's going, you know, very well. And then taking patients in the 50%, taking them to post-transplant maintenance, we think that number could be as high as over 70% in this data set. I think that was 50% was immediately put back on post-transplant, and then there are another three patients who are sort of in that window to potentially resume post-transplant maintenance. You know, I think this is a new paradigm for physicians, and they're super excited to do that. So, you know, it's not gonna be for everybody, but we do expect the majority of patients to go back on therapy after transplant.
And then I guess your second part, your second part of your question was about following up on data at a medical meeting. I think we're excited to get the NDA filed this year, and I think that's the number one priority, but obviously, we'll follow up with you know additional data at a medical meeting. We generally don't comment on what, what that you know whether we until we have something accepted. So right now we're anticipating having a presentation at an upcoming meeting for sure, where we present the full data set.
Thanks so much.
Thanks, Anupam.
Our next question is from Brad Canino from Stifel.
Hey, good morning, and congrats from me on these results as well. And really thank you for all the data analysis provided. Two questions from me. First, just what are your expectations for the potential length of post-transplant maintenance? And I realize your data are still maturing here, but what have you learned from the experience of other AML-targeted therapies? And can you tell us if at least the initial revumenib experience has matched that?
Let me let me ask Neil to make a comment on your question. Thanks for the question, Brad.
So, the question is regarding the length of post-transplant maintenance. So as we've described in the data, in the script, in fact, we've had, you know, patients commencing their 8th cycle of post-transplant maintenance in the current dataset. And this is, you know, very consistent with what we've previously reported at EHA 2023, for instance, where we described patients receiving treatment for, you know, some patients for almost a year. So, you know, our expectation, as Michael alluded to, physicians are extremely encouraged by the ability of revumenib to give them and their patients an opportunity to go to transplant. You know, many of these patients have actually failed prior transplant, and therefore, the opportunity to bring these patients to transplant is an extremely, is an extremely important one for patients and their physicians.
Our anticipation is because these these patients are, you know, at risk of relapse, is that they will be kept on post-transplant maintenance as long as possible. And and we have the prior experience to demonstrate that that is the case. T he other point that I'd like to reiterate that kinda supports this is the point that Michael made, is that either, you know, over 70% of patients have either started post-transplant maintenance, 50%, or, you know, could bring that number to over 70%. And I think that with these data coming out and when we present the data, you know, in more detail at a forthcoming medical meeting, that news is gonna get out, right? The word, the word will spread that this is a treatment option.
As more patients and their physicians have access to the drug and really understand the potential for the drug to provide benefit, we expect that patients will be kept on post-transplant maintenance for as long as possible.
Great. And if I can have a follow-up, I wanna know, how do today's results impact your view of the NPM1 probability of success, really for the regulatory CR/CRh number next year? And do you anticipate any of the differences in use of transplant in the NPM1 trial population that could influence that CR rate? Thank you.
Yeah, Brad, thanks for the follow-up. So look, I think we're extremely encouraged by these results. The consistency that we've seen in the Phase I this year and what we reported in the phase one for NPM1 was, you know, on the CR/CRh rate, was the same as what we saw for KMT2A, 27%. And I think what's interesting and what we learned in this trial is these are different populations of patients, right? They're treated differently, meaning KMT2A versus NPM1. KMT2A, the patients are in their mid-30s in this trial and that sort of lines up with demographics. So they're younger patients who are about 80% fit for transplant. So the goal of treatment for these physicians is to get them to transplant as quickly as possible and potentially put them back on drug.
That's a paradigm shift, obviously, that we've reported on today. We're excited about it. The NPM1 patients, in contrast, are older, right? They're so they're in their mid-60s, generally, and the majority of those patients are not fit for transplant. So what we would expect, going forward, and we'll see what the results look like in the Phase II, is that not only would the CR/CRh rate be, you know, similar to what we, what we provided in the Phase I, but with the lower rates of transplant, we would expect that patients might be able to have full count recovery and, you know, higher numbers potentially before... If they receive a transplant before getting there.
There's just not that aggressive drive to move them to transplant as quickly, and so we think that could accrue potentially to a higher CR/CRh rate. So that's, you know, that's obviously data to come, but we're, we're encouraged by and learning all the time from the data that we're generating.
Makes sense. Thanks again.
Thank you.
The next question comes from the line of Eva Privitera from TD Cowen.
Hi, good morning. Congrats on the data, and thanks for taking our questions. My question is on the durability. Do you expect the median duration response to continue to evolve and get longer, even though there's less than half of 46% of patients still in response? And can you walk through how that calculation is done?
Sure. Thank you, Eva. Nice to, nice to speak with you, and thanks for your question. So just to point out a couple of things. First of all, 6.4 months includes about half of the patients still on therapy and in remission. So we do think it's a bit early days to... Even though there is a median, we calculate that based on a Kaplan-Meier curve. So there are several patients still continuing on, and we expect that to elongate over time. So that is a, you know, an important thing to watch as we see. As we've seen that in the Phase I. Our Phase I experience is where they started, and the duration lengthened over time, and so we're encouraged by watching these patients, obviously, with the impact of maintenance as well.
You know, just to also point out, these are, this is the first time we're reporting on duration of response on just KMT2A patients. Our Phase I experience included both NPM1 and KMT2A experience. So that it's, you know, a little bit different than our Phase I, just pointing out the differences there. But we do believe that, that the encouraging start to the duration calculation at 6.4 could certainly lengthen over time as we watch these patients.
Great. Thank you so much. And a follow-up. Are you aware of studies looking at differences in transplant outcomes between patients who had CR, CRi, or CRp versus CR, CRh? Are there any differences in outcomes in in waiting for the response to get to a CR, CRh, or the outcomes are the same if the patient went into transplant with a CRi or CRp?
Yeah, let me, let me ask Neil to comment on that. Good question. Thank you.
Yeah, thanks for the question. We are aware of a paper in press that does exactly the kind - or at least under review - that does exactly the kind of analysis that you're, that you're describing. We haven't seen the paper, but our understanding is that the, the analysis indicates that, yeah, that there is no difference in outcome, right? In other words, taking the right patient to transplant with the, with prior to achieving a CR, CRh, those patients have this - have similar outcomes to patients who are transplanted with CR, CRh. Just a caveat, we haven't seen the paper, but we have - you know, we are aware that those data are right there.
Perfect. Thank you so much.
Thank you, Eva.
The next question comes from Peter Lawson with Barclays.
Great. Thank you. Thanks for taking the question. Just as regards to the patient that moves on to transplant before reaching CR, CRh, and any details you could provide around those if they go to CRp or CRi, et cetera? And then the Phase I study where patients went on to transplant as well, was that a similar scenario where some of them didn't achieve CRh? Thank you.
Yeah, Peter, thanks for the, thanks for the question. So look, I think the breakdown of patients, we had a very high percentage, relatively speaking, a high percentage of patients who were not fully recovered their counts. So I think we have that in the slides presented today. So CRp and MLFS, you know, you know roughly 40% of the patients were, you know, not completely recovered in their count. So a lot of patients who were... And as I think we mentioned, eight patients who were taken to transplant before being able to recover, recover their counts, that's a you know, significant number. And as you look at the CR, CRh rate, the pool of analysis of 23% in the AML population was 24.5%.
If you kinda do the mental math of if those patients had recovered their counts, I think as Neil pointed out in the script, you would have had, you know, upwards of, you know, high 30s of response rate on the CR, CRh. Obviously, that's not the goal of treatment for these treating physicians. They drive them to transplant as quickly as possible, and they're not waiting for these count recoveries. So that's just, that's just how the, how the practice works, how the practice of medicine works here. But we are very encouraged, and we do know that, some of these, call them incomplete responders, do quite well on transplant. As Neil just pointed out, some of that data is unpublished, but, indicating that, you know, the paradigm is, is really important to, follow up on. Maybe Neil wants to make a comment.
Yeah, just, just one follow-up. I think you're asking about the breakdown of patients who went to-....The eight patients who went to transplant without achieving CR, CRh. We haven't provided that breakdown today, so we will be providing it at a forthcoming medical meeting.
Yeah, that's true. Thank you. Do you get a sense that, in Phase I of the pivotal study, that there were more patients getting to just achieving kind of an incomplete response before going on to transplant, with physicians more comfortable with the drug to nudge patients onto transplant?
Yeah. Thanks for the question, Peter. Our fewer patients in the Phase I versus the Phase II had an incomplete response. So again, I think if you look at the, if you look at the patients who had gone on to transplant, in the Phase I, eight patients had a CR/CRh before going to transplant versus six in this population in the Phase II. The non-CR/CRh going to transplant in the Phase I was two patients, 20%, versus in the Phase II was eight patients. So again, 57% incomplete went to transplant in Phase II versus 20% in Phase I. It's a stark difference, and it's obvious. It's based on what I've said today, I think those are it kinda lays it out pretty well.
Gotcha. Okay, thanks so much. Thanks for the additional detail.
Thank you, Peter.
The next question is from Michael Schmidt with Guggenheim.
Hey, guys. Congrats on the results, and thanks for taking my question. Perhaps a couple of regulatory questions. With respect to the planned FDA submission, will this be exclusively based on the interim data presented here, or will you do another data cut before submitting the FDA, to the FDA? And then the results in the peds, are they consistent with the overall analysis? And do you think you have enough data to potentially get a broad label, including peds as well? And lastly, any updates based on the results on your future studies or ongoing studies, any changes to some of the trials that you're conducting beyond the refractory setting? Thank you so much.
Yeah, Michael, thank you. Thanks for the questions. I'm gonna ask Neil to comment on the regulatory FDA submission question first.
Thanks for that. Thanks for the question. So as I mentioned in the script, you know, we have BTD for KMT2A. So we've been in very close collaboration and many close discussions with the agency, over the last year or so. As I also alluded to in the script, the study design was modified in discussion with the agency to enable the interim analysis, based on the 57 patients. So, to exclude the null hypothesis as we mentioned earlier. So the, and as I also mentioned, the IDMC have recommended that the study be stopped for efficacy, and the company is following that recommendation. So, you can obviously, we're discussing the filing with the agency at the moment.
We don't get into detail of those discussions at the moment. But you can infer from what I've said, that our expectation is that we would file based on the interim analysis, since we've actually, you know, we followed the IDMC recommendation. In terms of the question with respect to pediatric patients, look, overall, the data are consistent across all of the patients that that were included in the study. And then the third question was regarding any modifications to future studies. We're not really ready to to discuss that at this time.
Yeah, and I'll just follow on-
Great, thank you.
To Neil's comment about future trials. We are excited about some data that coming towards the end of the year, as I mentioned in the script, about about combinations and the ability to to dose revumenib in combination, both with chemotherapy and ven. And so we're excited to talk a little bit about that, and obviously, we're starting trials, frontline trials-
Mm-hmm.
In addition to what we have going on. So it's a lot of momentum around new work that we are gonna be doing with revumenib and emerging results there as well. So stay tuned.
Thank you, Michael.
The next question is from Yigal Nochomovitz from Citigroup.
Hi, Michael and team. Thanks very much, and congrats on the results. I just wanted to follow up a little bit more on those eight patients that were taken to transplant without the CR/CRh. Just curious, from a regulatory perspective, if you could comment on how the FDA views that metric. It's obviously not part of the formal CR/CRh efficacy metric, but but how does the, how does the FDA think about that additional aspect in terms of getting to transplant without the formal count recovery?
Yigal, thanks for the question. I'll let Neil address it.
So yeah, thanks for the question. So first of all, from a regulatory perspective, you know, I won't repeat the answer that I just gave to the previous question, but clearly, we, you know, I would just summarize by saying we have been in close collaboration, worked closely with the agency since before and since they granted BTD for us. So we believe that the point estimate that has been observed in the overall pooled analysis, as long including or in addition to the durability of response, the duration of response is robust. And obviously, we can't you know, speculate on the outcome of discussions with the agency, but we feel very confident.
With respect to your question about patients going to transplant, and so you know, the agency will always consider the totality of the evidence, right? And what is, there are the strict sort of, the the strict regulatory pieces that they will look at, but they will always consider the totality of the evidence. And what we are hearing, and they will be speaking to many of the same KOLs that we're speaking to, is that the opportunity to take patients to transplant is absolutely paramount in this, in this scenario, right? These patients have really no treatment options, or really have very few treatment options prior to revumenib. You know, historically, fewer than 5% of these patients would actually get to transplant. And here we are, you know, reporting, you know...
Many, many, many, many, many times more than that, right? Going to transplant. So fold fold increases over over the historical situation. And, you know, KMT2A's physicians will tell the agency that, and that the agency knows this, right? The people who will be looking at these data are hematologists. They've treated patients. They understand the importance of the data. So just in summary, we expect that the agency will take into consideration the totality of the evidence.
Okay. Okay, that's very helpful. And then just a few other rapid-fire questions. You could you comment on the median time to CR/CRh for the AML cohort? That's the first one. Second, is there any early comment on OS, or is it not mature enough? And then third, with respect to ALL, you had, I think, eight patients, and you also indicated that you're closing the enrollment for the study. So is that enough? Is eight enough ALL patients to support the filing? Thanks.
Thanks, Yigal. Let me start, maybe Neil can follow on here. So median time to transplant, I think we have not reported on yet. I think we can say that it was-
Oh, I'm sorry.
Sorry, go ahead.
I meant median time to CR/CRh. Sorry-
Ah.
Median time to CR/CRh.
Sorry. Thank, thank you. Maybe I misheard you. So we haven't reported on that either yet, and that'll come in a-
Okay
... in the dataset at the medical meeting. But look, I can say qualitatively that patients are doing... You know, getting to their their response, their first response very quickly. Best response sometimes takes a little bit of time. As you've seen, there's a difference between patients recovering their counts. And so some of those patients are just getting taken quickly to transplant. So we'll report more about the kinetics of response at the when the full dataset is available, both in terms of CR/CRh as well as time to transplant. I think you asked about median overall survival. That's obviously something that we'll look to report on-
Yeah
... down the line. We don't have that available today. And then I think your third question was about closing of the trial, the study cohorts for KMT2A. That was the recommendation of the IDMC, and we're following that recommendation, and that those cohorts will be stopped. So that's that's in accordance with the protocol as well as what the IDMC has recommended. And so that's, that is the, that is the plan. The other other piece of it is that NPM1 obviously continues enrolling. So, and, Neil, go ahead.
Just just one minor add. The pooled analysis... I think, I think you also asked, you know, would the small number of ALL patients be sufficient to give us the broad label? The the pool, Look, it was anticipated that there would be far fewer ALL patients included in the pooled analysis. It was anticipated by the agency, it was anticipated by us. The way, the way the analysis has been designed, as I mentioned specifically in the script, it has been designed to potentially support the broad label of acute leukemia with KMT2A. So those are the... You know, the agency was on board with that design, you know, when we, when we put it in place. So that is the topic of the discussion, one of the topics of discussion with the agency right now.
Okay. Thank you very much.
Thanks, Yigal.
Our next question is from Kalpit Patel with B. Securities.
Yeah, hey, good morning and congrats on meeting the endpoint today. For the next update at the medical meeting, are you, are you gonna provide any transfusion independence data from AUGMENT-101? I know this was a key secondary that the FDA looked at for other targeted agents, so just curious how how that's shaping up now.
Yeah, thanks, Kalpit, for the question. You're right, transfusion independence is a secondary endpoint, something obviously we're measuring. And we'll, you know, obviously see about, you know, when we can present that data, hopefully at an upcoming medical meeting, not too far away, but we'll have, we'll have more to say about that as we go.
Okay. And one more question on the ALL patient population. Can you confirm that you don't need to meet that 10% lower bound confidence interval for the ALL subgroup to secure regulatory approval?
Yeah. Thanks, thanks for the question, Kalpit. Look, I think the agency, as Neil pointed out, the agency is, has been pleased with the data we presented both in the Phase I and now here, and they'll be looking at it in the Phase II. It's largely consistent. It's all very consistent data. I think the ALL population is smaller. Overall response rates have been consistent. So I think the agency has looked at the Phase I data and gave us breakthrough therapy with the same statistical plan, right? It's the ability to pool the data and together ruling out the lower bound of 10%. And that's, that's what we've done. So I think we've met the hurdles, and we expect to be able to submit the NDA this year.
Okay. Great. Thanks for taking the question.
Thanks, Kal.
The next question comes from the line of Justin Zelin with BTIG.
Hi, team. Congrats on the data, and thanks for taking my question. I wanted to ask about the on-target differentiation syndrome seen. Are you able to give additional color on how quickly symptoms resolved and whether you'd expect the incidence or severity of differentiation syndrome to decrease with combination treatments in upcoming studies?
Yeah. Thanks, Justin. I'll let Neil comment on differentiation syndrome.
Yeah, thanks, thanks for the question. We have not presented today data on time to resolution of the symptoms. I think important, the most important information that we've provided today with respect to DS is that overall it's manageable. No patient's actually discontinued as a result of differentiation syndrome. So that points to the manageability of DS. And as we've discussed the data with with investigators, they're pretty nonplussed by it, right? For them, it's it's expected, it's easily managed. Actually, those are the words that were used to me over the weekend, "Easily managed." And again, they notice, they noted that no patient had actually discontinued.
With respect to, you know, the potential in combination, in combination, Michael kind of alluded to, without us giving any specific information yet, but we hope to be able to disclose combination data later this year, is that we're pleased with how the combination studies are progressing. Not yet in a position to provide detail, but we are making good progress.
Great. Thanks for taking my questions.
You're welcome. Thank you, Justin.
The next question comes from the line of George Farmer from Scotiabank.
Hi, good morning. Thanks for taking my questions, and congrats on the data. Again, a bit more on the adverse events. With respect to differentiation syndrome, maybe you could talk a little bit about how you think about managing that, and do you think is this gonna be an issue, a review issue with FDA? Do you expect some sort of risk mitigation plan, a REMS plan? And then also regarding QTc, can you comment as to whether you saw any arrhythmia, arrhythmias or any other cardiac abnormalities?
Yeah, thank you. Thank you, George. I think, maybe I'll ask Neil to comment on on on the side effect profile.
Yeah. Sure. Well, as mentioned, differentiation syndrome is easily managed. You know , that's that's the observation of the investigators actually managing the patients. Whether it's, you know, just early use of steroids, just carefully monitoring their patients, and ensuring that, you know, the best supportive measures are put in place. And, you know, our data actually speak to that, the fact that that is working, since patients are not discontinuing. And they're remaining on study despite differentiation syndrome. Differentiation syndrome is an expected on-target effect of revumenib, or... And more broadly, the class of targeted agents for the treatment of AML, as well as other hematological diseases. But it's, but it's expected.
So these investigators are pretty adroit at actually managing it. And and again, I will repeat the words that they've spoken to us over the weekend, and prior to that, which is that they feel that it's relatively easy to manage. The other thing to note is that the pharmacokinetic profile of, yeah the pharmacokinetic profile of revumenib probably lends itself to, you know, somewhat more straightforward management of the DS associated with it. With respect to your question on QT, I'm sorry, could you repeat your question on QT? I beg your pardon.
Yeah. I was just wondering if you saw any cardiac abnormalities, like arrhythmias or anything like that, associated with QT prolongation?
Yeah. So so what we've actually described today, and we will provide much more detailed information at a future date, is that the overall rate of QT went down, right? So 23% reported in the previous observed in the previous, and in the current analysis, compared to 53%,54% in as close to a like-by-like comparison with the Phase I data that we presented at ASH and published earlier this year. So overall, the QT, the incidence of QT is going down, very manageable, no discontinuations, and you you know, people feel pretty comfortable.
Right. And I'll add on, no arrhythmias, no-
Yeah.
Yeah. And this is all, you know, lab abnormality and and obviously picked up in a routine EKG.
Okay, great. And sorry, just back to my original question, that kind of from a regulatory perspective, do you expect anything related to differentiation syndrome? I mean, you have BTDs. Do you have these ongoing discussions with the agency? Just wondering if it's come up. And then also, did you see any DS in the maintenance phase of the study post-transplant?
Yeah, we haven't, we haven't broken those data out, but I think, DS, you know, is is is sort of idiosyncratic in terms of its timing. But no, I think we haven't obviously identified one population of patients within the Phase II that, in terms of time point, where that could come up. And, you know, the agency... Look, the agency's aware of the DS. I think physicians are heightened to it across, as Neil mentioned, across the different, you know, molecules that are being tested in this, in this population. And so, you know, our ongoing work with the agency is that they would appreciate our ability to monitor for DS.
And the properties of our drug, putting aside what other drugs have experienced with very severe DS, you know, our our experience has been such that we have, you know, you know, relatively shortish half-life can control with steroids, and get the DS under control. And I think physicians, and up until now, the agency is obviously, you know, aware of it, but not concerned relative to what, what we've put out. So, I mean, I think that's, that's obviously ongoing discussion about our filing, and we'll, we'll, we'll report more later.
Okay, great. Thanks so much.
Thank you.
The next question comes from the line of Joel Beatty with Baird.
Hi, thanks for taking the questions. For ALL, where there was one out of eight patients that had a CR/CRh, what was the duration of response for the one patient who had the CR/CRh? And then did any of the seven patients who didn't reach CR/CRh go on to transplant?
Yeah, Joel, thanks for the question. Look, I think we haven't broken down the outcome on the CR/CRh patients. But I will say again, more qualitatively, we'll have a lot of detail on this at a medical meeting, but I think, a fair number of the patients, a good number of the patients that are in CR/CRh have gone on to post-transplant maintenance, and we'll say more about that later. But but it is very encouraging, obviously, related to where we are in measuring how the outcomes look for those patients.
Okay, thanks. One other question. On the lower bound of 10% that was used in this trial, would it also make sense to use that same lower bound in the NPM1 pivotal trial?
Yeah. Thank you. Thanks, Joel, for the question. Yeah, I think the powering assumptions that we laid out, we've said from the beginning, they that they were the same from across KMT2A and NPM1, and that's our expectation, that we would be ruling out, you know, 10% lower bound.
Thank you.
Thank you.
There are no further questions in the queue. I'd like to turn the call back to Michael for closing remarks.
Thank you, operator. Thank you all for joining us to hear about our results today for AUGMENT-101. We're extremely excited about having the opportunity to present the results today and obviously to follow on with additional information at an, at an upcoming medical meeting. Certainly, it's an exciting time for the company, and we're, we're in a really great position to execute on all of our milestones and deliver for patients as well as all of you. So thank you so much, and we look forward to continuing our discussions. Have a good day.