AGIO

Good day, and thank you for standing by. Welcome to the First Quarter 2026 Agios Financial Results and Business Highlights. [Operator Instructions] Please be advised that today's call is being recorded. I would now like to hand it over to our first speaker, Morgan Sanford, Head of Investor Relations at Agios. Please go ahead.

Thank you, operator. Good morning, everyone. Thank you for joining us to discuss Agios Pharmaceuticals First Quarter 2026 Financial Results and Business Highlights. You can access the slides for today's call by going to the Investors section of our website, agios.com. Please note, we'll be making certain forward-looking statements today. Actual events and results could differ materially from those expressed or implied by any forward-looking statements because of various risks, uncertainties and other factors, including those set forth in our most recent filings with the SEC and any other future filings that we may make with the SEC. On the call with me today from Agios are Brian Goff, Chief Executive Officer; Cecilia Jones, Chief Financial Officer; Tsveta Milanova, Chief Commercial Officer; and Dr. Sarah Gheuens, Chief Medical Officer and Head of Research and Development. Following prepared remarks, we will open the call for questions. With that, I am pleased to turn the call over to Brian.

Thanks, Morgan. Good morning, everyone, and thank you for joining us. Next slide, please. At the start of the year, we outlined our 2026 strategic priorities, which are designed to drive both near-term execution and long-term value creation. We are off to a strong start entering another catalyst-rich year with clear momentum across these priorities. Turning to first quarter highlights on the next slide. We delivered $20.7 million in net revenues, representing 138% growth year-over-year. The first quarter marks the U.S. commercial launch of AQVESME in thalassemia with the REMS fully operational as of the end of January. And already, we have shown strong initial demand. We continue to expect 2026 operating expenses to be approximately flat versus 2025, and we ended the quarter with a strong balance sheet, including over $1 billion in cash, cash equivalents and marketable securities. Importantly, we've advanced two priorities that are key to our growth inflection. First, the U.S. commercial launch of AQVESME in thalassemia is off to a strong start with 242 prescriptions written as of March 31st by REMS-certified physicians, building significantly on the 44 prescriptions we reported as of the end of January. This early progress reflects solid execution as the launch continues to broaden. Tsveta will provide additional details shortly, but the early momentum highlights the strong work and rare disease capabilities of the Agios commercial team. Second, following our pre-sNDA meeting with the FDA in the first quarter, we now plan to submit an sNDA for mitapivat in sickle cell disease in the second quarter under the U.S. accelerated approval pathway, marking an important step toward expanding our PK activation franchise into a significantly larger indication. I also want to underscore the caliber of our team whose ability to respond rapidly and rigorously to FDA feedback reflects the deep regulatory and scientific expertise we've built at Agios. Next slide, please. Stepping back, our strategy is to build a sustainable rare disease company, anchored by a foundation in rare hematology. In the near term, our focus is on executing the AQVESME U.S. commercial launch in thalassemia and advancing the mitapivat sNDA filing in sickle cell disease. In parallel, we are preparing for important mid-term catalysts, including Phase II top line data for tebapivat, our next-generation more potent PK activator in both lower-risk MDS and sickle cell disease this year. And over the longer term, we continue to advance our early-stage clinical programs and selectively evaluate expansion into other rare hematology diseases rather to support our sustained growth. With that, please advance to the next slide, and I'll turn the call over to Cecilia to discuss financials. Cecilia?

Thank you, Brian. The next slide summarizes our first quarter financial results. As we have previously shared, we will report mitapivat net revenues with U.S. and ex-U.S. components. In the first quarter, we delivered $20.7 million in worldwide mitapivat net revenues with $18.8 million from sales generated in the U.S., driven by the recent launch of AQVESME in thalassemia. Outside of the U.S., we reported $1.9 million in sales, reflecting expected quarterly fluctuations. We reported $81 million in R&D expense in the first quarter, an increase of roughly $8 million from prior year due to workforce-related expenses supporting pipeline advancement efforts as well as increased mitapivat process development expenses. We also reported $48 million in SG&A spend, up approximately $7 million from the prior year due to an increase in activities to support the U.S. commercial launch of AQVESME in thalassemia as well as an increase in stock compensation expense. We ended the quarter with over $1 billion in cash, cash equivalents and marketable securities, positioning us well to remain disciplined as we invest to maximize portfolio value and build a pipeline for long-term growth. Turning to our approach to capital allocation on the next slide, our priorities remain clear. First, we will continue to maximize the U.S. commercial launch of AQVESME in thalassemia. Second, we are managing operating expenses in a way that is aligned with our long-term value creation. Based on our current plans and accounting for the mitapivat confirmatory clinical trial in sickle cell disease, we anticipate 2026 operating expenses to be approximately flat compared to 2025. Finally, we will continue to diversify our pipeline, leveraging both internal capabilities and external innovation as we continue to execute our 2026 priorities with a disciplined approach to long-term growth. Please advance to the next slide, and I'll turn it over to Tsveta to cover commercial highlights and early AQVESME's use thalassemia launch dynamics.

Thank you, Cecilia. Next slide, please. Our commercial performance in the first quarter reflects exceptional execution as we transitioned the focus of our field force from PK deficiency to thalassemia. In the U.S., net revenues were $18.8 million, driven by strong early AQVESME launch demand. Outside the U.S., we reported $1.9 million in net revenue, driven mainly by thalassemia utilization in the GCC. This is in line with our expectations given early market access dynamics ahead of securing government procurement. As in prior quarters, we expect to see continued variability quarter-to-quarter, driven by ordering patterns, inventory dynamics and gross to net. Please move to the next slide. I'm very encouraged by what we are seeing from the AQVESME U.S. launch so far, and I want to start by acknowledging the tremendous work of our commercial, medical and patient support teams. Launch execution in rare diseases is complex and the early progress we are seeing reflects both strong preparation and the depth of rare disease commercialization expertise we have built at Agios, supported by close coordination across the organization. 242 prescriptions were written in the first quarter by REMS-certified physicians, serving as an important early indicator of strong demand, keeping in mind the REMS became operational in late January. Here are a few points that are worth highlighting to help frame how we're thinking about these early signals. As we exited the first quarter, early adoption was concentrated among highly engaged patients, including transfusion-dependent and motivated non-transfusion-dependent patients. This is consistent with expected early launch dynamics. In the first quarter, time from prescription to initiation was shorter than expected. This was due to early engagement by patients with stronger motivation to initiate treatment, physician readiness to prescribe as well as effective REMS coordination. However, we continue to expect average initiation time lines of approximately 10 to 12 weeks in the coming quarters as we advance deeper into patient segments with less frequent clinical engagement. We are encouraged by the geographic breadth of early prescriber adoption, which has been driven by community-based hematologist oncologists. What we're seeing so far gives us confidence in our launch readiness and the quality of demand in the early days of launch. That being said, we do not view early prescription volumes as translating into a steady run rate at this early stage of launch, particularly as demand moves more towards non-transfusion-dependent patients and adoption progresses beyond the most motivated, highly engaged patients. The next slide captures both, the strong early reception of AQVESME and how we're building towards sustainable growth. Feedback from the field has been very encouraging. Physicians and patients recognize AQVESME's meaningful clinical profile. REMS onboarding is running smoothly, and our patient support services are helping patients initiate therapy. As we look ahead, our focus is on three things: first, expanding prescriber engagement across both academic and community settings; second, broadening adoption into non-transfusion-dependent patients who represent most adult diagnoses; and third, advancing payer access to support timely treatment initiation. Taken together, we are encouraged with how AQVESME is being received in the early days of launch, and we are focused on executing against the key levers that will drive durable adoption over time. I'm very proud of the team's execution to date. The performance in the first quarter reinforces the team's launch readiness and deep understanding of this market. We believe this strong foundation positions us to deliver on both the launch of AQVESME in the U.S. as well as potential future launches as we look to expand our rare disease portfolio. Please move to the next slide. And with that, I will hand the call over to Sarah to cover key R&D highlights from the quarter.

Thank you, Tsveta. Next slide, please. We continue to advance a robust pipeline anchored by our PK activation franchise and complemented by differentiated early-stage clinical programs. In the first quarter, we announced plans to initiate two pediatric mitapivat trials in thalassemia, ENERGIZE-KidsT in transfusion-dependent patients and ENERGIZE-Kids in non-transfusion-dependent patients. We look forward to the potential to expand access to this transformative medicine into pediatric populations. Finally, we are looking ahead to upcoming second quarter readouts, including Phase IIb top line data for tebapivat, our next-generation PK activator in low-risk MDS. This study evaluates 10-, 15- and 20-milligram dose levels across a broad patient population with eight consecutive weeks of transfusion independence as the primary endpoint. While this represents a higher risk opportunity, we see meaningful potential for an oral therapy in this setting. Please move to the next slide. In the first quarter, we completed a pre-sNDA meeting with the FDA and aligned on a path towards U.S. accelerated approval for mitapivat in sickle cell disease. Since that meeting, we've had a series of informal and formal engagements to gain official alignment on the confirmatory clinical trial required under this pathway. We are pleased with the progression of these discussions and now expect we will file an sNDA in the second quarter. We look forward to sharing additional data from the RISE UP Phase III trial at an upcoming medical congress, including analyses that informed our selection of the confirmatory clinical trial's primary endpoint. Taking a step back, as we consider development of the confirmatory trial design, we emphasized operational feasibility, including enrollment time lines and time to completion while looking to maximize probability of success and the potential to further enhance the mitapivat label should U.S. full approval be granted upon results of confirmatory trial. Next slide, please. In parallel, we are advancing tebapivat, our next-generation PK activator in Phase II studies across low-risk MDS and sickle cell disease. Tebapivat was intentionally designed to go beyond first-generation PK activators. It is structurally differentiated with potent dual activation of PKR and PKM2 and PK and PD properties that support once-daily dosing without the need for a taper. Importantly, the early clinical data reflect these design features. In sickle cell disease, tebapivat demonstrated a long half-life of approximately 87 to 93 hours, dose-dependent reductions in 2,3-DPG and increases in ATP and pharmacodynamic effects that remain durable for up to four weeks after the last dose. We also observed a mean hemoglobin increase of 1.9 grams per deciliter at the 5-milligram once daily dose. Beyond red blood cell metabolism, tebapivat shows broader biological activity driven by PKM2 activation. In preclinical models, this translated into antifibrotic effects, including reduced glomerular injury and myofibroblast signaling, supporting the potential for disease-relevant activity beyond mature red blood cells. In low-risk MDS, we observed early clinical signals, including transfusion independence in the low transfusion burden cohort. However, we observed 60% lower drug exposure relative to healthy volunteers, which prompted investigation at higher doses. The ongoing Phase IIb study, which is evaluating higher doses in a broader lower-risk MDS population will test the hypothesis that deeper PKR and PKM2 activation may extend biological activity into erythroid maturation in the bone marrow. In sickle cell disease, our Phase II study is designed to rapidly assess hemoglobin response and key markers of hemolysis to confirm whether this deeper biology translates into broader clinical benefit. We look forward to reporting top line Phase IIb data in low-risk MDS in the first half of this year, followed by top line Phase II data in sickle cell disease in the second half of 2026. With that, please move to the next slide, and I will hand the call back to Brian for closing remarks.

Thank you, Sarah. Next slide, please. As you've heard today, 2026 is shaping up to be a growth inflection and catalyst-rich year for Agios, with meaningful progress across our commercial business and our pipeline. In the first half of the year, we advanced the regulatory path for mitapivat in sickle cell disease, and we expect Phase IIb top line data for tebapivat in lower-risk MDS, along with Phase I healthy volunteer top line data for AG-236. In the second half of the year, we anticipate Phase II top line data for tebapivat in sickle cell disease as well as Phase Ib proof of mechanism data for AG-181 in phenylketonuria. And throughout the year, we remain focused on executing the U.S. commercial launch of AQVESME in thalassemia with the goal of building a strong and sustainable commercial foundation. Next slide, please. Stepping back, we believe Agios is differentiated by the combination of a growing commercial base and a pipeline increasingly weighted towards later-stage high-value opportunities. As shown here, our current pipeline represents greater than $10 billion in potential market opportunity in 2030. Most importantly, everything you've heard today is grounded in our commitment to the patients we serve, patients living with serious and often underserved rare diseases who are still waiting for better treatment options. I also want to recognize and thank our employees. Their focus, expertise and dedication are what make this progress possible from advancing critical clinical and regulatory milestones to executing a complex commercial launch with care and discipline. With that, we appreciate your continued interest in Agios. And I'd now like to open the call for questions. Operator, please open the line.

[Operator Instructions] Our first question comes from the line of Samantha Semenkow from Citi.

Congratulations on the early launch progress for AQVESME. And just sticking with that theme, first question then is just a little bit about the demand of AQVESME you're seeing thus far in the second quarter. I'm wondering if there is a bit of a bolus component in the first quarter from those highly motivated patients. But as you look into the second quarter prescription performance, are you seeing a similar cadence in those prescriptions coming in as well as an increase in REMS-certified health care professionals? And I have a follow-up.

Sure. Thanks, Sam. I'm going to let Tsveta comment. And of course, we're going to stick to the first quarter dynamics, but there's obviously good momentum that we were proud to report today. So Tsveta, you want to take over?

Absolutely. So as I said, we are very excited with the early launch and the progress we've made. We said we had 242 prescriptions from REMS-certified physicians as of March 31st. The early uptake is really driven by the highly engaged and motivated patients, which included both the transfusion-dependent patients and the motivated non-transfusion-dependent patients. I wouldn't take Q1 to be the run rate for upcoming quarters. But what I can tell you is that we still expect very strong demand and uptake as the team continues to execute very strongly and the reception from both patients and physicians on the AQVESME profile has been very, very positive.

And Sam, you had a follow-up?

I did. Yes. That was helpful. A couple of follow-ups on tebapivat. Just first on the timing of the MDS data. I'm wondering if there's any additional clarity you could share there on when that data will come this quarter? And then just secondly, on sickle cell disease, I'm wondering how you're thinking about the market opportunity for mitapivat given some recent competitor's data? And then just how do you think about developing mitapivat? And obviously, you're moving towards accelerated approval filing, but you have tebapivat in the second half, that could have potential best-in-class efficacy based on those early data signals you walked through in the prepared remarks. Just how are you thinking about that market developing as we go forward?

So we'll go in sequence. Sarah can comment on tebapivat for MDS and basically, given the timing that we're expecting.

Exactly. So Sam, the timing that we've highlighted is the first half of this year. And so that is what we're sticking to. And then for sickle cell disease, the timing is the second half of the year and the teams are making great progress towards those deliverables.

And then I'll turn it back to Tsveta to comment on -- we're clearly, Sam, in a position of strength, having mitapivat and all the progress that we talked about this morning for our accelerated pathway for sickle cell disease and then the benefit of having tebapivat, the next-generation more potent PK activator that we're looking for to Phase II data. But Tsveta, perhaps you can talk about the overall franchise goal that we have.

Yes, absolutely. We see a very significant commercial opportunity in sickle cell disease, including both mitapivat and tebapivat. When we think about mitapivat, we see sickle cell disease as a disease that can support multiple treatment options, and we will be looking to maximize the commercial opportunity, assuming that we have a label. And that's driven by the fact that we've seen a very strong response and positive response from the KOL community on the strength of our hemoglobin responder data. They are communicating about the need of antihemolytic agent, especially an agent that can -- with hemoglobin responders can demonstrate a potential benefit in other meaningful endpoints such as quality of life and potential reduction in pain crisis. So we haven't seen the HIBISCUS data yet to be able to comment more on but we're starting from a position of strength when you think that this is our third indication in the market. There is a strong familiarity of that community with the product. We have over 1000-patient years of data and a strong market experience, and we will see that as a good anchor for our franchise building. When it comes for tebapivat, of course, we'll need to see the Phase II data. We'll need to see how the competitive environment moves forward, but we'll be looking to have a best-in-class positioning with that product, and we'll provide more information as we get the data.

Our next question will come from the line of Alec Stranahan from Bank of America.

Congrats on all the early launch progress this quarter. Two questions from me, one on sickle cell and one on the launch in thal. I guess, first on thal, in patients transitioning from the clinical study to commercial drug, is covering costs of therapy part of ensuring continuity of treatment? Just trying to think through how many of the 242 scripts for patients moving from the clinical trial and how they might translate to revenue this quarter and going forward? And then on the sNDA for sickle, curious when you expect to get feedback from the regulator on the proposed design of the confirmatory study and whether that's an update you'll share or if the next we'll hear on the program is just that the sNDA has been submitted.

Yes. And I think Sarah can -- we'll take them in sequence, starting with thalassemia and maybe just comment on the open-label extension and the studies.

Exactly. So Alec, so patients are in open-label extensions on the thal clinical program. So those are still ongoing and of course, help us to continue to highlight the maintenance of effect in this patient population. And in addition, the proportion of U.S. patients in those studies is small because it's a big global study. In regards to sickle cell disease, we are very pleased with the progression of the engagements we've had and the pace of the engagements we've had with the FDA, which, of course, allows us to further fine-tune the time line for submission. So we've updated to say that we would file in Q2. More details on the clinical trial, we will highlight before it goes on clinicaltrials.gov. And then, of course, we've stated that we will also present data at or around EHA and that data did inform us in this trial. I do want to take a step back here and just highlight that, as I stated in my prepared remarks that the trial, of course, is also designed in such a way that we prioritize operational feasibility and probability of success here. And so that is going to be our focus with this.

Okay. Maybe I could just follow up just on the continuity of treatment piece. I guess of the 242 scripts, I guess, how many of those were booked as revenues in the quarter? And I guess, how do you see that evolving sort of as payer access comes online over the coming quarters?

Cecilia, do you want to comment on the metrics?

Yes. So as we stated, we split U.S. and ex-U.S. revenues. So it's probably U.S. revenues, the way to think about it is we guided PKD to be about $45 million to $50 million for a year, and the quarter has been in line with that with the rest coming in from thalassemia. There is a lag on the prescriptions to when patients get on therapy, and that's what Tsveta was saying. We've seen it be a little faster than what we thought, but we think it's going to eventually be in that 10- to 12-week range.

Our next question comes from the line of Emily Bodnar from H.C. Wainwright.

First one, with your conversations with the FDA about the sNDA for sickle cell disease, are you also expecting a REMS for sickle cell disease? Or is that only for thalassemia? And then a follow-up question. With the Phase II sickle cell data for tebapivat expected later this year, can you maybe give us some expectations about what you'd like to see relative to Phase II data from mitapivat and etavopivat to kind of get confident in that best-in-class profile?

So Sarah, we'll start with continued encouraging interactions with the FDA and the question on REMS.

Yes, of course. And as you know, we now have optionality because we have PYRUKYND and AQVESME. Both of these are options, each having different pros and cons. Either way, our teams would be able to execute on any of those options. And as it relates to the Phase II data, it's a dose-finding study. So of course, we're looking for a dose in Phase II to bring forward, but we're also looking for depth and breadth of hemoglobin response.

Our next question comes from the line of Eric Schmidt from Cantor.

Congrats on a terrific launch. Maybe on this 242 prescription number in the first quarter, that's obviously an enormous number. I think, Tsveta, you told us back in February that through January 31, you had 44 prescriptions. So it looks like there's been a pretty meaningful acceleration in February and March. Maybe you could just confirm whether my math there is correct. And maybe square the circle relative to the comments you made about not extrapolating forward the current run rate because if anything, it seems like you're on an accelerating path.

Yes, we are very excited about the progress, Eric. And the 242 prescriptions from REMS-certified physicians of January 31st reflect the totality of the first quarter. As a reminder, we started actually actively promoting the drug as we got label. So the demand was generated throughout the whole quarter. The REMS became operational at the end of January, but the demand was generated throughout January as well. So I'll look at the quarter as a totality. And that's what I mentioned, I wouldn't take these two numbers and kind of extrapolate from there in the future quarters and wouldn't take that run rate. But we are still expecting to see a strong demand moving forward as the team is executing and the patients and physicians are very positive on the profile and looking to engage further.

And Eric, maybe I'll just take this opportunity to reinforce adding to your comments that what's so special about the AQVESME launch is we have 3 key ingredients. First is AQVESME addresses a significant unmet need with thalassemia. Secondly, the community, i.e., physicians as well as patients are already reflecting enthusiasm for the profile. And as you just said, third, Tsveta and the Agios team are very well prepared, and they know how to execute, and we're very proud of their early progress.

Terrific progress indeed. Do we have a sense of what percent of the initial REMS-prescribing patients are likely to convert or what the conversion ratio is?

So in the initial quarter, as I mentioned, we really kind of captured some of the most motivated and engaged patients and our conversion from prescription to treatment initiation was actually faster than expected. As the quarters progress over time, we still expect the initiations to be 10 to 12 weeks always. We'll try to shorten it. But the primary driver for that is that we'll be moving into patient segments that have less frequent interactions with the health care system as we go deeper into the NTDT segment as we've spoken in the past.

Maybe asking in a different way, have you lost any of the 242 patients that you now no longer think are likely to convert?

So far, I think we could characterize, Eric, that the REMS has been well embraced by both the physician community as well as, as Tsveta says, the motivated patients. And we feel very confident with the high conversion, I'll call it, of those early patients that have started on or were prescribed AQVESME and then converted on to therapy.

Yes. Sorry, Eric, maybe I didn't get exactly your question, but the REMS is not a hurdle to treatment initiation at all. What we see in terms of a conversion rate and it's very typical for rare disease launches. So we're not out of the extraordinary because of the REMS.

Our next question comes from the line of Marc Frahm from TD Cowen.

Congrats on the progress with AQVESME. Maybe just following up on some of the answers to Eric's questions. It sounds like at least some of these -- the extra kind of 200 prescriptions that you're kind of talking about now versus the end of January, I guess, maybe were even written before January. Is that right? They just weren't by a REMS-certified physician and kind of what's changed is the REMS certification status. Is that the right way to kind of square the commentary? And then some of this kind of caution around that trajectory of TRx maybe slowing or the fill time pushing out a little bit. Have you actually seen that yet? Or you're just cautious that, that may happen as we move into future quarters?

So thanks, Marc. Maybe what will help here is so that I can just like take a step back to the launch timing and what occurred in the first quarter because there was an initiation of demand and then there was the operationalization of the REMS. Do you just want to talk through that and then reflect on the source of the 242 prescriptions.

Yes, absolutely. So the 242 prescriptions are reflective of all of the work that we've done in excellent launch preparation. We had a lot of clarity of where likely the prescriptions are going to come first, and we initiated these interactions and promotional activities as soon as we got the label. So they're a reflection of the work that we've done for the whole quarter. In the first month, we didn't have the REMS operational, and the team still did an excellent job to get prescriptions from REMS-certified physicians in that phase of the launch. And we continued on that journey once the REMS was operational. Obviously, more physicians who are waiting for that operational date to start prescribing, they did start prescribing. We are very pleased with what we are seeing right now because the prescriptions are coming from a very healthy geographic breadth. They are coming from the community prescribers, where the majority of the patients are managed right now. And we see this kind of highly motivated and engaged patients starting therapy, which is fantastic for us because we know that the thalassemia community is actually very well connected and that early launch experience with the patients will actually support the kind of the positive feedback and the profile of the product as well. So what I can tell you is that moving forward, I wouldn't take the two data points in Q1 and extrapolate from there, but I'm very confident that we'll have a strong uptake and penetration moving forward as we continue to the launch, typical with non-life-threatening rare disease conditions.

And Marc, on the second part of your question about the 10 to 12 weeks that Tsveta had commented on in her prepared comments, we have been encouraged that these motivated patients have translated to therapy faster than that in some cases. But again, this is relative to the motivation of both the physician and the patient. And the reason to guide on average, that's an expectation going forward is as we penetrate further into the non-transfusion-dependent patient population, we expect there will be perhaps a mitigating factor on the enthusiasm aspect, and it might take a little bit longer for those patients to convert to therapy.

Okay. I completely understand that, but maybe just to push on it a little bit, presumably also as you get further into the launch, you also have a dynamic of more payers kind of having regular processes and things that tends to kind of shorten the time lines within a given payer, but I guess, it sounds like you expect it to be more than counteracted by that kind of difference in enthusiasm from the patient itself.

Yes. We'll definitely -- the team is doing an excellent job right now, and we haven't had any payer hurdles so far. Of course, we'll continue to look for ways to shorten the time from prescriptions to treatment initiation. We'll look to advance. It takes about six months on average to get the payer policies in place. But as of now, similar to patients and physicians, payers have been very receptive of the profile and market access has not been a hurdle.

And our next question comes from the line of Salveen Richter from Goldman Sachs.

This is Lydia on for Salveen. Congrats on the launch updates here. Maybe just another question on the launch. Could you maybe just speak to the treating physicians and treatment settings that you're seeing here? And are you still seeing a majority of prescriptions coming from the community hem-oncs? And is the team starting to engage with physicians beyond those who were targeted ahead of the launch?

Yes, absolutely. So we see a very healthy start of the launch when we think from a prescriber base. We've seen prescriptions coming both from the academic and community setting, but the majority of the prescriptions are coming from the community setting, which is exactly as we expected it. And that's driven by the fact that patients with thalassemia are actually managed mainly in the community setting. We see prescriptions coming from across the country, which is fantastic. And as we move forward, the patients will continue to increase the breadth of prescribing. And of course, we'll focus on that as well, but the majority of the business is going to continue to grow breadth.

And our next question comes from the line of Tessa Romero from JPMorgan.

I just wanted to double-click back here to one of the initial questions on the call here. Ultimately, what do you see as the implications of Novo's recent results to next steps at Agios? And how does this change your view of what you need to see to drive tebapivat forward in sickle cell disease as well?

Maybe Sarah can start with our focus on mitapivat and then we can comment on tebapivat as well.

Sure. So we haven't seen the full HIBISCUS results yet. So as Tsveta highlighted, I mean, we see a clear commercial opportunity in sickle cell disease with mitapivat. And as she highlighted as well, there are multiple players given the prevalence and the disastrous nature of this disease. And of course, we'll look to maximize commercial opportunity with mitapivat. That is possible with our data sets in RISE UP. We have, again, a very strong antihemolytic profile in our data set. The strength of the hemoglobin responder data is definitely there because as we've highlighted, we have seen impact on VOCs, but sickle cell disease is more than VOCs. We've seen impact on hospitalizations, fatigue, quality of life. So there is really a lot of excitement for our drug in the community, both by patients and physicians. And of course, we are also -- as we highlighted in our prepared remarks, very pleased with the progression of the engagements we've had with the FDA so that we're now able to update our expected filing into Q2. So we are very pleased with where we are.

Okay. Great. And Sarah, if I can just follow up quickly on that point. Is there anything that you would like to better understand in the fuller HIBISCUS data set when we do see it?

Well, yes, obviously, like the data is very limited right now that we have to our availability. So anything as it relates to standard study metrics, I would love to see.

And our last question comes from the line of Greg Renza with Truist.

This is [indiscernible] on for Greg. Congrats to the launch, Tsveta. One question on AQVESME. So with the momentum continuing to build, you have 242 prescriptions in the first quarter. Are you starting to see any early signals of patient persistence, patients staying on therapy, given that this is a chronic setting? And any differences in the patterns between transfusion-dependent versus non-transfusion dependent? And I have a follow-up.

Absolutely. As we said, we are very early in the launch, and there is a time lag between a prescription and treatment initiation and then the patients need to go from a month of therapy to start seeing what the continuation rate. But we've seen PYRUKYND in PK deficiency performing extremely well in the real world. We expect to see the same strong performance in thalassemia as well. Sometimes we talk about the REMS as kind of paperwork and work, but actually, it helps with the frequent interactions between patients and physicians and actually can support continuation of therapy as well. So we'll wait and see. That's one very important factor we'll continue to monitor.

Got it. And a second question on mitapivat in sickle cell disease. So assuming accelerated approval, how do you think about the opportunity for early uptake based on hemoglobin as a surrogate endpoint and potentially on the label while additional outcomes data are being generated in the confirmatory study and especially in light of etavopivat hitting the VOC endpoint?

Yes. This is a little bit reflective of what Sarah had commented on as well that sickle cell disease has very high unmet need. And as Sarah said, it's a multi-dimensional disease. There are many things to address clinically within sickle cell disease. And we stand proud and tall with the RISE UP data that we've seen, particularly as well the responder analysis. And Tsveta and her team are, of course, already preparing commercially for that potential opportunity ahead with the accelerated approval pathway.

And just if I may add, the data from RISE UP that we've highlighted to physicians and patient communities has been very well received.

And if I may, could you maybe expand a little bit on the confirmatory study? What are you thinking in terms of the confirmatory endpoint? And how might that compare to the potential VOC data that we might see in HIBISCUS just when it comes to treatment selection?

Yes. So thanks. So the endpoint, as highlighted, is informed by the RISE UP data set in which we've collected data systematically prospectively. So we've had also great engagements with the FDA, and that has progressed very nicely. So again, we are now able to speak to our intent to file in the second quarter. We've also highlighted before that we will be presenting data at or around EHA around all of the data, so including the data that informs this confirmatory trial and that we will also share more ahead of our posting on clinicaltrials.gov. The last thing I wanted to stress, and this is really important, this is a confirmatory trial. So we really have prioritized the operational feasibility as well with probability of success to be able to deliver meaningful data that then, of course, would allow us at that time to hopefully be able to put that data into label at the time of full approval when the results allow. So we are very excited about where we currently are. We have really great confidence in our data and the path that we are on.

And this concludes the question-and-answer session. I would now like to turn it back over to Brian Goff for any closing remarks.

Well, thanks a lot, Victor. Thanks, everyone, for joining. The first quarter clearly reflected solid execution across our strategic priorities from the early progress with the U.S. commercial launch of AQVESME in thalassemia, as we've discussed, to continued advancement toward mitapivat sNDA filing in sickle cell disease and to maintaining a disciplined financial approach with multiple meaningful catalysts ahead this year, we believe Agios is well positioned as we move through 2026, and we look forward to continuing to update you on our progress, including at our planned investor event during the 2026 EHA Congress. So thank you very much, everyone.

Thank you for your participation in today's conference. This does conclude the program. You may now disconnect. Everyone, have a great day.