Hello, ladies and gentlemen, and welcome to the Day One Biopharmaceuticals' Third Quarter of 2024 Financial and Operating Results Conference Call. Please be advised that this conference call is being recorded. I would now like to turn the conference call over to Joey Perrone, Senior Vice President of Finance and Investor Relations. Please go ahead, sir.

Thank you. Hello, everyone, and good afternoon. Welcome to Day One's third quarter 2024 financial and operating results conference call. Earlier today, we issued a press release, which outlines the topics we plan to discuss today. You can access the press release and the slides to accompany this conference call on the Investors and Media section of our website at www.day1bio.com. An audio webcast with the corresponding slides is also available on the website. Before we get started, I'd like to remind everyone that some of the statements that we make on this call and information presented in the slide deck includes forward-looking statements as outlined on Slide 2. Actual events and results could differ materially from those expressed or implied by any forward-looking statements. We encourage you to review the various risks, uncertainties and other factors included in our most recent filings with the SEC and any other future filings that we may make with the SEC. These forward-looking statements are based on our current estimates and various assumptions and reflect management's intentions, beliefs and expectations about future events, strategies, competition, products and product candidates, operating plans and performance. You are cautioned not to place any undue reliance on these forward-looking statements, and except as required by law, Day One disclaims any obligation to update such statements. Today, I am joined by Dr. Jeremy Bender, Chief Executive Officer; Lauren Merendino, Chief Commercial Officer; Charles York, Chief Operating and Financial Officer; and Dr. Samuel Blackman, Co-Founder and Head of R&D. I will now turn the call over to Jeremy.

Thank you, Joey, and good afternoon, everyone. I'm pleased to share our third quarter earnings results with you today. I will also provide an update on the three priorities we've emphasized for 2024. First, the successful launch and commercialization of OJEMDA; second, progress advancing our pipeline; and third, the expansion of our portfolio. Day One had a remarkable third quarter. Our OJEMDA net product revenue for Q3 was $20.1 million, more than double what we reported last quarter. Our early commercial experience is laying the groundwork for the company's future growth. We see OJEMDA in relapsed/refractory pLGG as a foundational opportunity for Day One. Our commercial execution following approval in April of this year has driven persistent and steady growth of OJEMDA sales. We believe that growth reflects the significant unmet need for new treatment options in the relapsed/refractory pediatric low-grade glioma space. We previously disclosed that the median duration of treatment observed for patients in Arm 1 of FIREFLY-1 is 23.7 months. As we work towards a more complete analysis of the follow-up data from our registrational FIREFLY-1 trial, the median duration of response for patients in Arm 1 has now extended from 13.8 months to 18 months, which we believe speaks to the value OJEMDA is bringing to patients. Given that unmet need, we remain confident in continued future growth in OJEMDA sales and in the opportunity to increase the breadth and depth of OJEMDA prescribers. As we look ahead to 2025, we remain focused on enrollment in FIREFLY-2, our global Phase 3 front-line pLGG trial and the opportunity it provides to demonstrate the clinical benefit of tovorafenib as a standard of care in the front-line setting. You may also recall that we established an ex-U.S. partnership for OJEMDA with Ipsen earlier this year. We are working closely with our partners there to support successful registration and commercialization of OJEMDA in the EU and additional territories. We are also on track and on plan to dose the first patients in Q4 this year or early Q1 next year in the Phase 1 trial of DAY301. DAY301 is the PTK7 targeted ADC we in-licensed midyear following clearance of the IND by the U.S. FDA for that program. In DAY301, we have an opportunity to establish a first and/or best-in-class program with potential across a broad set of adult and pediatric solid tumors. Finally, as always, we continue to seek opportunities to drive value for our shareholders. Our business development team continues to actively look for differentiated high-quality clinical stage programs that fit our portfolio criteria and provide opportunities to improve patients' lives and build value. We are in a strong financial position with over $0.5 billion in cash to fund our operating plan and to expand our portfolio in 2025. We've made great early strides toward delivering on our mission in 2024 to develop new medicines for people of all ages with life-threatening diseases, and we're looking forward to continuing that work ahead. I'll now turn the call over to Lauren to discuss our commercial progress in greater detail.

Thank you, Jeremy, and hello, everyone. Today, we are thrilled to provide an update on our launch of OJEMDA with remarkable progress in Q3 on multiple fronts. In the five months since our approval, we have delivered a total of $28.3 million in net revenues, driven by over 850 total prescriptions and high payer approval rates. The momentum is encouraging, and we believe there is continued opportunity for the brand. There are many more eligible pLGG patients who can benefit from OJEMDA, and we have laid a solid foundation for future growth as we continue to further penetrate this market. This quarter, we delivered $20.1 million in net product revenue for OJEMDA, which represents an impressive 145% increase over last quarter. There are two primary factors driving this growth. First, we continue to drive a strong flow of new patient starts. We are expanding our prescriber base and increasing use by existing prescribers, resulting in a steady influx of new patients. Secondly, we've seen a high percentage of patients continuing on therapy each month. This high continuation rate for pLGG patients is consistent with what we saw in FIREFLY-1, where patients remained on OJEMDA for a median duration of about 24 months. In addition to these two demand drivers, OJEMDA has continued to see high payer approval rates. So the large majority of our patients are on paid drug with low utilization of our free drug programs. Our volume in Q3 grew by almost 160%, reaching over 600 total prescriptions. This reflects both the growing pool of patients on OJEMDA and the high percentage of patients continuing on therapy. We've also been able to nearly double our prescriber base in Q3 and about 80% of OJEMDA prescribers have no experience with OJEMDA prior to launch. Additionally, we're seeing increased prescriber comfort with OJEMDA with the number of HCPs with two or more patients on our drug continuing to increase. The breadth of patients receiving OJEMDA is also notable. Since launch, we've had significant uptake in treating both patients with BRAF fusions and mutations and with patients who have tumors that span the spectrum of locations for pLGG. We believe this broad applicability reinforces the value proposition of OJEMDA in the treatment of relapsed/refractory pLGG patients. As we analyze our data, we're seeing early signs of increasing use in second and third-line therapy. This is consistent with our expectations that as physicians gain greater confidence with OJEMDA, they will move it earlier in their treatment paradigm. Feedback from customers has been overwhelmingly positive regarding OJEMDA's product profile, our patient support programs and the overall ease of access to the medicine. However, we recognize that it will take time to fully penetrate this market due to the slower progression rate of this disease and the relative infrequency of treatment decisions. Through our efforts, we continue to build momentum for OJEMDA, and we see evidence of this in our market research as well as our sales results. In a recent survey of 24 pLGG treaters, 100% of them were aware of OJEMDA and over 90% of them intended to prescribe it. This is up from 64% from a larger survey done around launch. Additionally, when we look at the top tier of accounts that treat the highest volume of pLGG patients, over 80% have started one or more patients on OJEMDA. On the right, we've included a few quotes from our customers highlighting their belief in our product profile and how they are evolving their treatment paradigm to incorporate OJEMDA. In addition to making progress with physicians, in Q3, we also made substantial progress establishing published payer coverage. Since early in our launch, we've seen high payer approval rates, which are now about 80% across all payers. This has enabled us to have a high percentage of patients on paid drug. It's also important that we establish published coverage because that will reduce the number of patients who need to navigate an appeals process with their payer. We made a tremendous amount of progress on this front this quarter, increasing Medicaid coverage by 17% and commercial coverage by 48%. We can now say that the majority of patients have established coverage for OJEMDA with 62% of commercial and 67% of Medicaid patients having published coverage. As we look ahead to Q4, we continue to focus on the fundamentals that will drive our business. We must continue to grow the breadth and depth of our prescriber base, position OJEMDA as the standard of care in second-line treatment and secure payer coverage policies for the remaining patients who do not have coverage today. We're excited about the progress we've been able to make in the first five months of launch, but this is just the beginning. We continue to see considerable potential in this market, and we are highly motivated by the continued interest and excitement from our customers. Now, for more details on our financials, I'll turn it over to Charles.

Hello, everyone. Earlier today, we reported detailed third quarter 2024 financial results in our earnings release. These results highlight our continued focus on value creation. As Lauren mentioned, we have experienced strong patient demand for OJEMDA since launch, resulting in Day One recording $20.1 million of OJEMDA net product revenue in the third quarter, our first full quarter of revenue. Our Q3 results bring our year-to-date net product revenue to $28.3 million for 2024. Additionally, we closed two transactions, a license of our ex-U.S. commercial rights for tovorafenib and an equity financing, both of which resulted in over $280 million of incremental capital for Day One's future development. As we announced in July, we licensed our ex-U.S. commercial rights of tovorafenib to Ipsen for upfront cash, future milestone and royalty payments as well as an equity investment made at a market premium. As a result of that transaction, we recorded $73.7 million of license revenue in the third quarter of 2024. It is important to note that an incremental $4.5 million of license revenue will be recorded over the coming years. In a partnership such as ours with Ipsen, U.S. GAAP requires deferral and subsequent recognition of the allocated transaction price for the future R&D services Day One is contractually obligated to perform. While minor variability is expected, we believe the recognized license revenue will be approximately $300,000 to $500,000 per quarter. Cost of sales for the current quarter includes intangible amortization and sales-based royalties. As stated last quarter, we expect cost of sales to increase to 9% to 12% of net product revenue early next year as the sale of post-approval cost of inventory commences. Our total operating expenses were $64.1 million for the current quarter compared to $51.4 million in the same quarter last year. This increase relative to the third quarter of 2023 was driven primarily by commercial investments that supported the U.S. launch of OJEMDA. At Day One, we continue to approach capital allocation in a disciplined manner. We have a clear and focused operating plan and when paired with our strong cash position of $558.4 million, we are well funded for measured investment in expanding our pipeline and for continued investment in clinical development across multiple programs. In closing, our achievements during the third quarter of 2024 represented important steps in Day One's path to transformation to a commercially sustainable company with OJEMDA serving as the foundation of value and growth. These events included enrollment in our front-line pLGG trial for OJEMDA, DAY301, our PTK7-targeted ADC is nearing the clinic in the U.S., and we took multiple steps to successfully strengthen our balance sheet. We will finish the year strong with continued urgency and continued focus on delivering new medicines. Now, we will turn it over to the operator for Q&A.

Thank you. The first question we have comes from Anupam Rama of JPMorgan. Please go ahead.

Hey guys. Thanks so much for taking the question and congrats on the quarter. Just a quick logistical question. I think you noted around $2 million of inventory in Q2. Maybe you can comment on what you're seeing in terms of inventory levels in Q3 and how we should think about that going forward? Thanks so much.

Thanks Anupam. This is Jeremy. I appreciate you joining and the question. Let me ask Charles to comment on the inventory topic.

So, Anupam, from our perspective, as we look forward, it was important for us to provide the level of channel stock in the first quarter of revenue for us, so in Q2 of 2024, given the fact that there is stocking inventory as commensurate with our distribution model. In that quarter and going forward, what we will discuss is that the similar guidance that we provided, which is approximately two to four weeks of channel stock on hand. And when we look at that, that really translates into continued inventory and continued channel stock at the specialty pharmacies, but something that is not contributing materially to our overall revenue. We will not provide the individual number any further. We'll just provide some guidance if we're off that two to four week of channel stock on hand.

Thanks so much for taking our question.

Thank you. The next question we have comes from Joe Catanzaro of Piper Sandler. Please go ahead.

Hey everybody. Appreciate you taking my question and congrats on a nice quarter here. Just wondering maybe if you could sort of elaborate a little bit more on the cadence of new patient starts, whether what you saw in 3Q was sort of in line with what you observed in May or June, whether there are maybe still sort of early launch factors at play here? Or you believe what you saw in 3Q will continue for the foreseeable future moving forward? Thanks.

Thanks Joe for the question. Let me comment and then I'll ask Lauren to add any detail. What we saw in the third quarter is very consistent with what we did in the second quarter, and that is continued and consistent adds in terms of new patients. And that is the pattern that we expect going forward. We did not see any substantive change in that pattern in the third quarter relative to our launch quarter, which was the second.

Yes, we continue to hear from physicians that there are patients that they're treating today that have potential to go on OJEMDA's future. So we do believe there continues to be a lot of potential for the product to be used in more patients in the future.

Okay, got it. That’s helpful. And then if I could just ask one quick follow-up, I guess, a technical question. So the TRx number that you're mentioning here, is it fair to assume that each TRx is 1 month of drug supply? Or are there scripts being written for a longer term supply of drug?

Yes. Let me ask Lauren to answer that.

Yes. So, TRx is roughly a 28-day supply. The only exception would be for a quick start patient getting a second shipment, it's only two weeks, and that would count as a TRx, but we have very few patients leveraging our Quick Start program at this point since we have such high payer approval rates.

Okay, great. That’s helpful. Thanks again for taking my question.

Thanks Joe.

The next question we have comes from Andrea Newkirk of Goldman Sachs. Please go ahead.

Hi everyone. Thanks for taking the question. Lauren, could you just clarify the number of patients that you do have on drug currently? I think as of 2Q, it was 157. And maybe the breakdown there for EAP versus De Novo? And then just really quickly, what percentage of patients from that 2Q cohort did continue on treatment in 3Q? Thank you so much.

Yes, thank you for the question. So, we're not providing specific numbers. What I can say is that we provided the breakdown in Q2 between EAP and new patient starts. So that is the same. There were an additional three EAP patients that we transitioned in Q3 and now EAP transition is completed. So, all the other new patient starts are De Novo new patient starts in Q3. And the TRx numbers represent the refill prescriptions from patients continuing from Q2 as well as any prescriptions from the patients starting in Q3, both their initial script and any refills. And so TRx will be what we plan to provide moving forward.

Okay. Thank you. And then just you mentioned the high continuation rate. Are you giving maybe a number to that, if possible?

Yes. So, we've been really pleased with the continuation rate for pLGG patients. So, we see the discontinuations five months into launch is in the low single-digits.

Yes. Andrea, let me add to that, that we're observing in the commercial setting, what we very much would expect to based on the data that have been generated in FIREFLY-1, where you saw persistent treatment and long durations of treatment, at least so far in the launch. And nothing has really diverged from that expected pattern at this stage.

Thank you. The next question comes from Soumit Roy of Jones Research. Please go ahead.

Congratulations everyone on the great solid quarter. One quick question. If you are seeing any and getting any comments on the community setting physicians, what kind of traction you're getting there or any resistance in terms of they want to see a longer duration on drug before getting in?

Soumit, thanks for the question. Lauren, if you could answer that one.

Yes. So, we've seen significant uptake both in academic as well as community physicians. And some physicians had experience prior to launch through clinical trials and EAP. But when we look at our total prescriber pool, 80% of them had no experience prior to launch and a large number of those are in the community setting. So, we haven't heard any resistance in the community setting other than obviously, many of them are managing a smaller population of patients. So they may have less frequent opportunities to make a treatment decision. But other than that, we've seen uptake in both academic and community.

Thank you for that. I have a quick question about the front-line trial. Are you able to comment on whether you are enrolling patients who have been treated with MEK inhibitors after surgery, or are physicians facing any challenges in enrolling patients due to using MEK inhibitors post-surgery and before tovorafenib?

Soumit, let me hand to Sam for that one.

Yes, thank you for the question, Soumit. The front-line trial is for patients who need their first systemic therapy. Therefore, patients cannot receive a MEK inhibitor before tovorafenib in the front-line trial. Some patients will be enrolled after surgery, while others who are not eligible for surgery will also be included as their first treatment.

Thank you. The next question we have comes from Alec Stranahan of Bank of America. Please go ahead.

Hey guys. Thanks for taking my questions. Two from me as well. Maybe first, just a quick follow-up on the cadence of new patient starts in 3Q. Curious whether patients adds were fairly linear during the quarter or maybe some seasonal lumpiness during the summer? Any additional color you could add sort of on the cadence of new patient adds?

Alec, thanks for the question. The cadence, what we can say is that the cadence was very consistent. We didn't observe any significant seasonality. So, it was really very straightforward. And that's been true for both the second quarter, the post-launch quarter as well as this first full quarter.

Okay, thanks Jeremy. Makes sense. And maybe just a follow-up, given the new duration of response data you've shown from FIREFLY-1, wondering how you're thinking about this 18 months translating to the real world? Maybe anything you can say on types of patients you're treating currently versus the clinical study and any feedback you've been getting from the field would be great? Thanks.

So, first, let me comment on the new data that we did provide. The first is that we've seen duration of treatment data that we disclosed in the second quarter results of just under 24 months. And then the new data point that we disclosed in our release today is a duration of response data set. And let me ask Sam to comment first and then any other team members.

Yes, thank you, Alec. From the clinical perspective, I believe that the updated duration of response data will ultimately instill confidence in prescribers regarding the durability of the responses we're observing. Ultimately, the length of treatment is not necessarily tied to the radiographic response. We've discussed on numerous occasions that minor changes in tumor size, which might indicate radiographic progression according to standardized response assessment criteria, do not usually prompt physicians to halt or alter treatment. As we've mentioned before, pediatric neuro-oncologists focus on treating patients rather than scans. Therefore, while this may not alter the length of treatment or the decisions surrounding it, it does provide significant assurance that the responses we are witnessing are indeed very durable.

Great. Thank you and congrats on the progress.

Thanks Alec.

The next question we have comes from Ami Fadia of Needham & Company. Please go ahead.

Hi, good evening. Thanks for taking my questions. It would be helpful if you could give us some color on the number of patients that are on treatment. The way I was sort of doing the math based on the 600 prescriptions, assuming that all of the 157 from last quarter had three scripts each, that gets us to 471, leaving 129 scripts. And if you assume an average of one and a half months, that brings us to about 86 patients added in the quarter. Does that math roughly kind of align with what you guys are saying?

Ami, thanks for the question. As Lauren noted, we're not focused on the disclosure of specific patient numbers quarter-by-quarter. So, I won't comment specifically on the numbers that you arrive at. Our focus really is on driving overall commercial performance. And what I would reiterate is that the pattern that we observed in terms of the addition of new patients in the third quarter was very consistent throughout that quarter and indicates continued demand at a steady pace.

Got it. And then maybe just a quick one on DAY301. You're getting ready to start dosing patients or actually just started dosing patients. Can you just give us a high-level sense of what type of data could we expect to see next year? Thank you.

Ami, yes, we are poised to start that trial and dose the first patient relatively soon. I would reiterate our guidance here that, that will occur in Q4 or early Q1, and we're very much on track for that start. We have not specifically guided to when we'll have any early data from the Phase 1 portion of that trial. As you can imagine, that will depend on a number of factors. We do think there will be a lot of interest in the trial and that we'll move quickly. That being said, it isn't clear yet whether we'll have any specific data that will be published or available in 2025. So, we'll have to come back to that question and provide more detail on when those data may be available in subsequent quarters.

Understood. Thank you so much.

Thank you, Ami.

The next question we have comes from Andres Maldonado of H.C. Wainwright. Please go ahead.

Hi guys. Congrats on the quarter and thank you for taking my question. Maybe just two quick ones for me. The first one, looking prospectively at the collaboration with Ipsen, what is the impression they've given you on some of the differences of launching a RAF inhibitor in the U.S. versus the EU? And is there an approved RAF inhibitor in both scenarios where we could use as a reference point to set our expectations there? And then my last question on the PTK7. Obviously, competitors have generated intriguing signals across a myriad of tumor types. Curious on what's the thinking towards combination work here? And how much preclinical work has been done there guiding your strategy moving forward? Thank you very much.

Andres, thanks for the questions. Let me start with your question about Ipsen. There are outside of the U.S. and in the U.S., of course, a number of RAF inhibitors that are type 1 RAF inhibitors that have been approved. Those are really limited to adults with disease driven by predominantly V600E mutations in their tumors. And those have been around for some time. I don't remember the specific initial approval there. But those are distinct from OJEMDA's approval here in the U.S. OJEMDA tovorafenib is a type 2 RAF inhibitor and a unique mechanism of action for that reason, albeit against a similar target. In terms of the discussions that we've had with Ipsen, we can't really talk in detail about the nature of those. What I can tell you is that we have very clear alignment on the registration strategy for OJEMDA in markets outside of the U.S. and confidence in Ipsen's ability to achieve those approvals and are well on the way towards supporting their efforts for submission. With respect to your second question about PTK7 and potential combinations, I'm going to make one comment and then hand to Sam for a little nuance. From my perspective, one of the features of that specific program is that we can pursue through a Phase 1/1b and Phase 2 cohort expansion strategy, clear signal-seeking work that will allow us to understand the potential registration paths for that program across a fairly sizable number of tumors because we have the potential for single-agent activity. That, of course, does not address the longer-term question of whether those registration paths could involve combinations, which, of course, many of them may. For that, let me hand to Sam to talk in more detail.

Yes. Thanks. It's a thoughtful question. Just to build on what Jeremy said, our development plan, and I think I don't want to speak for all of my colleagues in drug development who are working on ADCs, but having worked in this space before, I think all of us share this common belief that a well-designed, well-targeted ADC is going to be active as monotherapy. And our early phase development program is designed to elicit a monotherapy signal of activity. If you look at the history of ADC development, combination work has taken place certainly in bladder cancer with enfortumab vedotin in combination with a checkpoint inhibitor, but that was really subsequent to the approval of that as monotherapy. I think for us, the most important thing is for us to be laser-focused on eliciting a monotherapy signal. As such, we've designed a very efficient Phase 1 clinical trial and look forward to bringing the same type of high-quality execution to it that we brought to our work in low-grade glioma. And we'll do, I think, all due diligence on potential combinations for later-stage development should it be necessary. But again, this next year is really about highly efficient execution of our Phase 1 trial.

Great. Thank you very much.

Thanks Andres.

Thank you. Ladies and gentlemen, we have reached the end of our conference call. Thank you for joining us. You may now disconnect your lines.