Good day, ladies and gentlemen and welcome to the Syndax First Quarter 2018 Earnings Conference Call. At this time, all participants are in a listen-only mode. Later we will conduct a question-and-answer session and instructions will follow at that time. [Operator Instructions]. I would now like to turn the conference call over to Ms. Melissa Forst with Argot Partners. Ma'am, you may begin.

Thank you, operator. Welcome and thank you to those of you joining us on the line and the webcast this afternoon for a review of Syndax's first quarter financial and operating results. I'm Melissa Forst with Argot Partners, and with me this afternoon to discuss our results and provide an uptake on the company's progress are Dr. Briggs Morrison, Chief Executive Officer; and Rick Shay, Chief Financial Officer. Also joining us on the call today for the question-and-answer session is Michael Metzger, President and Chief Operating Officer of Syndax. This call is being accompanied by a Slide deck that has been posted to the company's website, so I'd ask you to please turn to our forward-looking statements on slide two. Before we begin, I would like to remind you that any statements made during this call that is not historical is considered to be a forward-looking statement within the meaning of the Private Securities Litigation Reform Act of 1995. Actual results may differ materially from those indicated by these statements as result of various important factors including those discussed in the Risk Factors section of the company's most recent quarterly report on Form 10-Q as well as other reports filed with the SEC. Any forward-looking statements represent our views as of today, May 8, 2018, only. A replay of this call will be available on the company's website at syndax.com. And with that, please turn to slide 3, and I'm pleased to turn the call over to Dr. Briggs Morrison.

Thank you, Melissa, and thanks to everyone joining us on today's call and webcast. This afternoon, I'll share the progress we've made during the first quarter as we continue to execute on our corporate strategy in support of our primary mission to realize a future in which people with cancer live longer and better than ever before. Slide three briefly summarizes our corporate strategy, which includes developing three potential best-in-class molecules, entinostat, SNDX-6352 and our Menin-MLL-r portfolio, which are being tested at five ongoing clinical trials across six different indications. An additional important component of our corporate strategy is the opportunistic in licensing or acquisition of products that have both a compelling strategic fit and potential return on our investment. Slide our provides a summary of the investment highlights for Syndax. During this call, I will primarily focus on the progress we're making with our lead program, entinostat. I will discuss both our Phase III trial for breast cancer, which we received breakthrough therapy designation from the FDA, as well as our exciting ENCORE clinical trial program, which combines entinostat with PD-1 antagonist. Slide five provides a summary of the milestones we communicated on our last call back in March. I will say more about the abstracts we were representing at ASCO later in my comments and I will note that we now anticipate topline results from ENCORE 602 in the first half of 2019. Let me now turn to slide six and give you an update on E2112, our Phase III trial of entinostat in hormone receptor positive HER2 negative breast cancer. Slide six summarizes the trial design and endpoints. We will also summarize the key upcoming milestones. As we communicated previously, in the fourth quarter of last year, the ECOG Data Safety and Monitoring Committee completed the final…

Thank you, Briggs. Turning to slide 20, for the 3 months ended March 21, 2018, Syndax reported a net loss of $19.4 million or $0.79 per share compared to $13.0 million or $0.71 per share for the prior year quarter. First quarter 2018 R&D expenses increased to $15.3 million from $9.6 million for Q1 2017. The increase was primarily due to increased CMC development activities for SNDX-6352 and two initiating work on our Menin program. These increases were partly offset by completion of several entinostat Phase I clinical pharmacology trials and a decrease in E2112 costs. General and administrative expenses totaled $4.8 million during the first quarter of 2018 compared to $3.9 million for the prior year period. The increase in G&A was primarily due to increases in headcount, professional fees and patent related legal expenses. At March 31, 2018, there were $24.7 million common shares outstanding and on a fully diluted basis using the treasury stock method, we had 26.2 million shares. Additional financial details will be available in our 10-Q report, which we intend to file this week. Syndax ended the first quarter of 2018 with a cash balance of $113 million, which we believe is sufficient to fund development into 2019, enabling us to reach key development milestones. And looking ahead, we expect R&D expenses to be $15 million to $18 million for the second quarter and $62 million to $70 million for the full year. And total operating expenses are expected to be $20 million to $23 million for Q2 and $82 million to $90 million for the full year 2018. And now I'd like to turn the call back to Briggs.

Thanks very much, Rick. So looking ahead, we anticipate several key upcoming milestones summarized on slide 21. I've already discussed the upcoming data presentations at ASCO and the readout of the PFS results from our Phase III trial in hormone receptor positive HER2- breast cancer E2112. As I noted in my previous comments, the topline data from ENCORE 602 and 603 are now both anticipated in the first half of next year and we anticipate being able to decide to expand the modifying the colorectal cohort around the end of this year or in early 2019. With regards to SNDX-6352, we look forward to sharing both the data from our multiple [indiscernible] trial and the details on our clinical developing strategy. It's obviously going to be a busy year for us here at Syndax. As always, I'd like to thank the team here at Syndax month. I'd like to thank our collaborators and most importantly, the patients, trial sites and investigators involved with our clinical programs. With that, I'll open up the call for questions.

Thank you, ladies and gentlemen. [Operator Instructions] The first question is going to come from Chris Shibutani with Cowen.

Dave, many different clinical updates coming for you especially at ASCO, we're just coming of the fields of AACR as well you didn't mention but there was some early data that was presented there, talking about entinostat in combination with Nectar 214. I know that the folks at Nectar have commented about that and seem to express some enthusiasm there. Can you highlight some of the takeaways in which we're thinking about what kind of structure we might be able to see you continue to develop that work? How that might play out? Thanks.

Hi, Chris. Thanks very much for your question. So what we presented at AACR was a preclinical combination work done with Nectar 214 and entinostat and I think quite interesting combination therapy. We're continuing - we set of that collaboration with Nectar some time ago and we're continuing discussions with them about how we can bring that combination into the clinic and see if the preclinical findings translate into clinical advances as well. So those conversations are ongoing. We can't comment on whether it will come to fruition or not but we are having conversations with them.

The next question comes from David Lebowitz from Morgan Stanley.

Thank you very much for taking my question. I got a curiosity, given where you are with non-small cell and in refractory and with data before that was in the naïve, I guess what are the overall thoughts going forward in non-small cell, as what might the next steps be?

Thanks, David for your question. So you're correct that in the initial design of ENCORE 601, we had a cohort of naive patients and we had the cohort of refractory patients. In both cases, we met the criteria to expand the cohorts. We decided not to do that in the naïve patients because we were waiting for the results of some of the large ongoing Phase III trials. I think in retrospect, that was probably a good decision given where things sort of landed with readout from the KEYNOTE 189 trial and as I tried to sort of allude to in my comments, I think our focus is more on the patients who have progressed on both chemo and the PD-1. We think that's the growing area of unmet need and so our efforts right now are completely focused on that refractory population and at this stage, we are not progressing additional studies in the naive populations.

Sure. Thanks for that. And you we're also in colorectal cancer you were talking about the modification in the trial. Could you just go through the rationale behind the initial 25% threshold that was selected and how it has moved to 15%? What you learned from physicians versus what you had thought before?

Sure. So the initial design, the 25% was essentially a copy of what we had done in melanoma, aiming to be highly relevant with a high response rate. We continue to have a lot of conversations with colorectal physicians at that trial was enrolling and we got feedback that for sure if you had 25%, that would be quite interesting, but you guys shouldn't - not be interested in something that has perhaps a lower response rate, given how important it is to find new agents in this area and compared to some of the other agents that are used in this area that thought even 15% would be of interest. And I noted on our last call that we - it's an open label trial, we have seen activity. And so we went back and had a conversation with our collaborators and with the investigators and said maybe we should modify this so that if the true response rate is 15%, we have sufficient power to be able to detect that and to characterize that and to make sure that we have a sufficient number of patients that we can also do the biomarker analysis. So that was the reason to expand the colorectal population and to change the threshold for the study.

Thank you for taking my questions.

The next question comes from Konstantinos Aprilakis from JMP Securities.

Hi, good afternoon. Just a real quick question. The E2112 PFS data coming in Q3, just wondering if there is any accompanying data that we can expect or will it just be like a top line PFS number?

Right. So - thanks for the question. At the time that the data is released, so if the PFS result is positive, we'll get the data set from ECOG and obviously be in the process of getting ready to put together the NDA. Our anticipation is that the initial communication from the company would really just be top line results and we would look for inappropriate medical meeting to go through all the details around both efficacy and safety.

Okay, great. Thank you.

Next question comes from Bert Hazlett from BTIG.

Thank you. Looking forward to all the readouts upcoming here, Briggs, could you just describe some of the considerations - I know you give us more granularity with regard to the filing strategy in melanoma, but just some of the considerations that are at play for that particular PD-L1 refractory melanoma population?

Yes. Sure. Bert, so I think as we may have talked about previously, there is essentially -- we think of it as of two different populations, the patients – there are patients today who are being treated with a PD-1 antagonist as a monotherapy and their first therapy and then subsequently may receive CTL full avelumab and then there are other patients who are treated with both agents right up front. At the end of the treatment regimen, essentially you end up with cognitive patients who have received both the PD-1 and a CTLA-4 and our refractory to both. That population is likely to be the area of highest unmet need for those patients generally go -- if they're still suited then they'll go onto chemotherapy. The patients who have gotten the PD-1 monotherapy as their first treatment and have not yet received a CTLA-4 antibody are slightly different where from a regulatory and clinical point of view, people would want to know how does the agent compare to treating [indiscernible] as it for example. So we think of those as two different registration approaches and are considering options in both clinical settings.

Okay. Thank you. And then just kind of a broader consideration. There was a lot of data as Chris mentioned about a number of studies with regard to entinostat. Looking at the tumor microenvironment and their combination with entinostat with 214 was mentioned and then 9015 antagonist and other molecules. Is the company - is Syndax prepared to prosecute breast cancer as an indication? And as a path forward, as well as all the PD-1 combinations in addition to some of these additional novel combinations? Or are those just something we may have to wait and see on or for other people to do? Or how should we think about the other activity and the intriguing activity you've shown in some of the AACR work?

Yes. Thanks for the question, Bert, So obviously, as Rick went through our current financial situation and what we're funded to be able to continue to do, that of course includes the Phase III breast cancer trial and includes the ENCORE program as we've described it to you. As I said in my comments, as we go through the whole proof of concept program, we'll make decisions about, which of those things if you see single and multiple tumor types, we may decide to move forward as one and not others just depends on sort of the unmet need, that sort of competitive environment and where we think we get the best return. In terms of additional combination work, they're - as you know that there was a number of presentations are using entinostat in combination with a number of agents, with whom we actually had many conversations with people who wanted to test entinostat in combination with other agents. I think our view at this point is the data with Nectar 214 was in our view particularly exciting and as we said, we already have a collaboration with them preclinically so we're continuing that conversation. Some of the other agents who are people have expressed interest in combining with entinostat I think for now, we'll keep those on the back burner while we finish out the work that we're doing, but I think that's sort of where we are.

Okay. Just one more quick one then. The Menin-MLL-r inhibitor program, anyway to step on the accelerator with that intriguing program as well?

Great question. I ask the team every week. So we're doing everything we can to move as quickly as we can, but right now, the team is comfortable that they can get the IND file in the first quarter, but I asked the same question you just asked and we'll see if they can speed things up a little bit.

Okay. Thank you very much.

Next question comes from Matthew Kumar from Riley FBR.

Thanks for taking my questions. Kind of following on for thinking about the melanoma registration strategy, how do you think about the kind of broader landscape of Post-PD-1 drug as a decision calculus for whether you go strictly post-PD-1 in melanoma or post-PD-1 and CTLA-4?

Yes. Matthew, thanks very much for the question. So it is, again, you guys probably filed this just detailed into this. A number of molecules that are being developed in melanoma, it's a fairly busy area. I think the patients who have failed both the PD-1 and the CTLA-4 as I said it's probably the clearest unmet need because they really only have chemo as an option but once we have failed only a PD-1, there is at least the option of giving them [indiscernible] So we keep - try to keep track of as many of the competitors as we can. We do tend to think of them in sort of two different buckets. There is the buckets of what I guess we could call systemic therapies either antibodies or small molecules and the bucket of things that are interterminal therapies and we separate them simply because we believe that the systemic and oral therapies are probably just a little bit easier go to market strategy. And tumoro [ph] is just a little bit difficult to make sure that you have people trained who can inject liason. So we keep track of both of those and there is data accumulating in both spaces, both with viruses, with TLR antagonists, like three others. So if there is interesting space but I think failed both PD-1 and CTLA-4 probably is in more need and the evidentiary standards may be a little bit lower from regulatory point of view than for those who only fill the PD-1.

So to that end, what fraction of the patients in the Phase II have failed both PD-1 and CLTA-4 in the fully enrolled population?

Yes, I don't think we've revealed that data yet for the fully enrolled population for the data presented last year was about 2/3 that have gotten both.

Okay. Great. Thanks for taking my questions.

The next question comes from Christopher Marai with Nomura.

Hi. Good afternoon, guys. Thanks for taking my questions. First, just with respect to -- the colorectal cancer trial changed sort of what drove that? I know there is higher need – you were certainly bullish about the potential responses. Should we read into this, but you may see a sort of more responses and how that you initially anticipated, you kind of expanded the –due to that potential success and an ability roll patients and now we just in better data center look at? And initial [ph] responses kind of been observed and that sort of not replicated as a trial progressed? And then secondarily, with respect to this readout and some of the other entinostat in I/O coming up and particularly ASCO. Can you help us understand some of the biomarkers that might help overlay our understanding of the drug and its activity? Thank you.

Thanks, Chris. So for colorectal, again just to be very clear, the main reason for an expanding the enrollment was really around the statistical design of being able to assess the 15% response rate. So in the original design, you had to hypothesize 25% and a lower bound if you will of 10%, which means if you saw a 9% or 10% response rate, you might not even progress to the second stage of the trial. And as we talked to moral colorectal cancer and physician and our collaborators at Merck, we all agreed that that would probably doesn't make a lot of ,sense so let's change the specifics around the design and to make sure that if you had 10% at your first stage, you would still continue because your in the ballpark of being able to hit that 15%. So it was really around the statistical design and being able to adequately assess even a 15% response rate. The largest sample size also does give us more patients, potentially to look at biomarkers. So it goes to your second question about the biomarkers. It is - as I pointed out, a very comprehensive program. So there's as if looking at the tumor itself. So PD-L1 expression, tumor mutational burden of variety of different immune cells upsets as you know in colorectal cancer, there have been the description of various subtypes if you will of colorectal cancer trouble trying to get our hands around that. And also, we look at a variety of immune cell types in the peripheral blood. So it is fairly comprehensive review. It does take a little bit of work to sort of dig through all of that. As noted in my comments, I think in non-small cell lung cancer, one of the markers that we have been interested in, it does seem promising and you'll be able to see that data at ASCO. But it does take a little bit of time to make your way through all these various assets, collect the data, do the collaborative analysis, see if it actually predicts an independent model outcomes. So it's a lot of work but to be honest, I think it's really quite important. I think we've seen now in the I/O field that at least some companies have gone forward with very broad programs they haven't worked out. And others have tried to focus on specific subpopulations and those may have worked out better. So we really do think it's important if we can find bomarker defined population.

Okay. That's helpful. So it's more of an approach to the biomarker defined population rather than a unifying sort of view on entinostat's mechanism. Although I suppose the kind of intersect.

They do intersect and obviously, if there was a biomarker that was predictive of clinical benefit across various tumor types, so it was a sort of a unifying biomarker that obviously would be an easier thing from a development point of view. It's just a little bit early to be able to make that conclusion of course because we're still waiting for data from four of the other tumor types that we haven't read out yet.

Okay. That's helpful. And then in terms of more biomarker data that sort of SITC [ph] type you more, presentation in terms our more conclusive biomarker type [indiscernible] last quick one?

So I think that - again just to set equation, I think as I noted, it's a fairly comprehensive look at biomarkers so it will be an evolving story over time. And I am not sure I can say exactly when the story - as you do these analyses, something looks promising and we can follow up on it. \In other cases, you have to do more work until you find something, so it's a little hard to gauge a timeline for when the biomarker will advance to a point where we can then use it in subsequent to our trials.

Okay. Great. And then just follow-up on more our comment here, we've seen about a year ago now an indication that entinostat might be helpful in overcoming resistance or non-response to carbon inhibitors. You'd mentioned you have an ongoing discussion with respect to the other IO agents. I'm just wondering anything on the product side of the equation there? Thank you.

I would say there's nothing imminent on the Parkside.

All right. Thanks.

The next question comes from Tony Butler from Guggenheim Securities.

Yes. Thanks very much. I want to ask about 602 and triple negative if possible. Would you please remind us - I think there has been some data with pembro [ph] in triple negatives. I think the response rate was something around 20%, I could be wrong but if you remember that I would appreciate that? And the other comment is that there have been other data in combination pembro plus, a Park inhibitor and I guess the notion here is what would be a good level of activity you would like to see your predictivcy with concentric because I'm trying to understand what concentric has been able to show as monotherapy and can be seen and what would be good with entinostat on top, if that makes sense? Thanks.

Yes. Thanks a lot Tony. So I think a number of companies have reported monotherapy whether over the PD-1 or PD-L1 in triple negative breast cancer. And my recollection is the response rate is somewhere in the high teens. I don't recall it being dramatically different from one agent to another. I will just say the way the trial - the way 602 is set up, it's statistical approach is around PFS and its powered for hazard ratio of 0.7. So we'll obviously look at response rate to develop response PFS other endpoints but the statistical sign is surely based around PFS. I think again from a response rate point of view, I think in general, we're looking for -- this is in population of patients who are naïve to PD-1 antagonist. So if you were going to reduce response rate, you should be looking for some sort of material improvement in that - if you're looking be looking at PFS with a hazard ratio of 0.7 or so, I think that would be notable. But again, it's - I emphasize that both 602 and 603, all of these are what we consider proof of concept trials, early signs of efficacy and then you can dig into the data and see what you want to do going forward. Briggs Morrison Thanks. And just briefly the question on 602, slight delay, had of involvement than dragging a little bit as you anticipated it earlier and simply by the end of Q2 that’s really pushed into early part of '19? Thanks.

Yes. So we had anticipated 602 would readout top line data at the end of the year. The final enrollment has lagged us a tad. We still thin we're going to fit it in the second quarter, but as we look at that, we thought it was prudent to indicate that it's more likely that we'll get top line data in the first half of the next year.

Thanks, Briggs.

The next question comes from [indiscernible] from Oppenheimer.

Hi, this is Emma for [indiscernible] On E2112 the final [indiscernible] is negative next quarter, would you also simultaneously disclose the results of the [indiscernible] analysis to date? And then just to clarify what you then continue to conduct analysis for each interim OSS for 6 month intervals?

Right. Thanks for your question, Emma. So as you have correctly recalled, if PFS is negative, then with the DSMB meets, they do both of futility analysis for OS and a positive analysis for OS. So if PFS is negative and we communicate that PFS is negative, that would buy influence me that if futility analysis previously conducted, we know that they are probably were futility analysis and they we're also - the trial was not futile. So we wouldn't be able to tell you what the estimated hazard ratios were at that - at those various analysis that's not communicated to us by the DSMB, but one could buy influence bigger while CFS was negative so they were doing futility analysis and the had been negative to that time.

Right. Great. And then I believe last quarter you get 10% of OS events had an in the first interim, so that negative analysis when surprising. Is the second analysis still manage those expectations?

So the second analysis would be with the DSMB communicative it was that the trial will continue as designed but they did not give us an update on event date. So I'm not sure we can communicate that to you.

Great. Thank you.

I would now like to turn the call back to Dr. Morrison, for further remarks.

Great. Thanks again, everybody for your interest and we look forward to seeing all of you in Chicago.

Ladies and gentlemen, thank you for participating in today's conference. This concludes today's program. You may all disconnect. Everyone, have a great day.