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Operator
Good morning and welcome to Agios Pharmaceuticals fourth quarter in full year 2025 conference call. (Operator Instructions). Please be advised that this call is being recorded at Agio's request. I would now like to turn the call over to Morgan Sanford, Head of Investor Relations at Agios. Please go ahead.
Morgan Sanford - Head - Investor Relations
Thank you, operator. Good morning, everyone. Thank you for joining us to discuss Agios Pharmaceuticals fourth quarter and full year 2025 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.
Brian Goff - Chief Executive Officer, Director
Thanks, Morgan. Good morning, everyone, and thank you for joining us on today's call.
Next slide please. Just last month we outlined our 2026 strategic priorities which are focused on delivering long-term shareholder value. First, we're focused on executing a high impact launch of AQVESME for the treatment of thalassemia in the US.
Second, we see meaningful opportunity to expand our PK activation franchise into additional high value indications, including sickle cell disease and lower risk myelodysplastic syndrome with key catalysts this year for both opportunities.
Third, through the advancement of our early-stage pipeline with AG-236 and AG-181, we have the potential to unlock future value in hematologic and other rare diseases. And finally, we remain committed to long-term sustainability supported by discipline, capital allocation, and continued operational efficiency.
Building on those priorities, the next slide maps key pipeline catalyst in 2026 across multiple high value indication opportunities. The AQVESME launch in thalassemia is underway in the US and we look forward to the potential to expand our PK activation franchise into sickle cell disease and lower risk MDS.
These milestones and continued progress in our early-stage pipeline position the portfolio for growth and long-term value creation.
Next slide please. We exited 2025 with solid momentum across the business, commercial execution, pipeline progress, and continued focus on financial discipline which together provide a strong foundation to deliver on our 2026 strategic priorities.
Starting with commercial performance, PYRUKYND delivered $20 million in net revenue in the fourth quarter. Bringing full year 2025 revenue to $54 million reflecting robust year on year growth. In the fourth quarter we reported top-line data from the Rise Up Phase 3 trial and we'll meet with the FDA this quarter as anticipated for a Pre-sNDA meeting to determine the regulatory path forward.
Importantly, just before the end of the year, we received FDA approval for AQVESME, and the US thalassemia launch is underway. Finally, we recently completed enrollment in the phase 2 sickle cell disease trial of tebapivat with topline results expected in the second half of this year.
Importantly, we continue to operate from a position of strength, ending the year with approximately $1.2 billion in cash, providing flexibility to maximize the thalassemia US launch, pursue the path forward for mid pivot in sickle cell disease, and continue to advance our pipeline programs. Please move to the next slide and I'll turn the call over to Cecilia to provide additional details on our 2025 fourth quarter and full year performance as well as our 2026 outlook.
Cecilia Jones - Chief Financial Officer
Thank you, Brian. Next slide please. Our fourth quarter and full year 2025 financial results can be found in the press release issued earlier this morning, and additional details can be found in our 10-K which will be filed later today. Fourth quarter, worldwide hurricane revenue was $20 million. An increase of 86% compared to the fourth quarter of 2024 and a sequential increase of 55% compared to $13 million in the third quarter of 2025.
In the US, fourth quarter revenues of $16 million were driven by continued commercial focus in PK deficiency ahead of FDA approval for AQVESME, an additional ordering week in the fourth quarter, and favorable growth to net adjustments. In 2026, we expect US PK deficiency revenues to be in the range of $45 million to $50 million.
Outside of the US, revenue of $4 million in the fourth quarter primarily reflects inventory stocking ahead of demand driven by PT deficiency patients in Europe, transitioning from our global managed access program, where PYRUKYND was provided free of charge to commercial supply.
We anticipate a sequential decline in ex US revenues into the first quarter of 2026. Cost of sales for the fourth quarter was $1.9 million. R&D expenses were $88.1 million an increase of $5.3 million compared to the fourth quarter of 2024, associated with the advancement of our earlier stage pipeline program.
SG&A expenses were $51.6 million in the fourth quarter and roughly flat year on year. We ended the fourth quarter with cash equivalents, and marketable securities of approximately $1.2 billion. As a reminder, in future quarters, we will report mitapivat revenue as a whole, breaking out US and ex US performance.
Next slide, please. We remain committed to financial discipline as we work toward our goal of becoming a sustainable rare disease company. We anticipate operating expenses in 2026 to be roughly flat with 2025.
This guidance assumes investment to maximize launch of vestment in thalassemia in the US, gated investment for sickle cell disease, and operating model refinement.
Importantly, we see a clear path to profitability through our existing commercial presence in thalassemia and PK deficiency. Please advance to the next slide, and I will turn the call over to Tsveta to share commercial highlights for the quarter.
Tsveta Milanova - Chief Commercial Officer
Thank you, Cecilia. Next slide, please. As Cecilia noted, in the fourth quarter, PYRUKYND delivered $60 million in net revenue in the US, up 50% year over year, driven by continued demand in PK efficiency, an additional ordering week in the quarter, and certain gross to net adjustments.
Fourth quarter, Agios revenue was roughly $4 million which primarily reflects supply ahead of demand put through as PK deficiency patients in Europe transition onto commercial supply.
We expect this ordering to moderate in coming quarters. As expected, we continue to see quarterly variability driven by ordering patterns, inventory dynamics, and gross to net adjustments.
Fourth quarter performance underscores the strength of our commercial model and the foundation we're building for future growth, starting with the recent US approval of AQVESME for the treatment of anemia in adults with alpha and beta thalassemia, regardless of transfusion burden.
Please move to the next slide. I'm pleased to share that as planned, the final implementation of AQVESME was completed in late January to align with the approved FDA label, and we have already begun dispensing products. As of January 30, we have seen 44 prescriptions written by REMS physicians in the US.
Which reflects strong early recognition of AQVESME clinical value and excellent execution by our field teams. What is especially encouraging is the healthy breadth of early prescribers at this stage of the launch. We see strong geographic distribution and as expected, predominance of community physicians as early prescribers.
We are also seeing in these early days of launch, emergence of the patient profile we anticipated. Largely transfusion-dependent patients along with a group of highly engaged non-transfusion dependent patients. These early signals speak not only to our launch readiness, but importantly to our deep understanding of this patient community and their unmet needs.
Please move to the next slide. We are very encouraged by the early market response to AQVESME. Physicians consistently view its profile as addressing meaningful gaps in the current treatment landscape for thalassemia.
Importantly, this aligns with what we heard ahead of FDA approval. We are not seeing the REMS as a barrier to prescribing, with early experience suggesting the certification process has been straightforward. We are also seeing strong engagement with our patient support programs.
Initial experience indicates that patients do not view the REMS as burdensome, given the potential for meaningful clinical benefits, including reduction in transfusion burden and improvement in fatigue.
Taken together, this early feedback reinforces both the significant and magnesium thalassemia and the value proposition of AQVESME. It also reflects the strength of our pre-launch planning. On the next slide, I will take a few moments to discuss how we anticipate these demands will convert into treatment initiation and ultimately revenues in the first few quarters of launch.
There are three key steps in the AQVESME REMS certification process. One of those steps, pharmacy education and certification, is already completed as we use a single specialty pharmacy to dispense prescriptions and coordinate home delivery.
Additionally, physicians are required to be educated and certified on the AQVESME [1]. In parallel, once a prescription has been written, patients need to receive insurance authorization and complete a baseline liver test prior to initiating treatment.
Our comprehensive Patient Support Service, Agios has a strong track record assisting patients with the insurance authorization process for PA deficiency, which we expect to continue with thalassemia. Once these three components are completed, the pharmacy is authorized to dispense the prescription.
Patients will then complete monthly liver tests for the first six months and it's clinically indicated thereafter. Initially, we expect the time from prescription to treatment initiation to be on average 10 to 12 weeks.
As physicians are onboarded and access expands, we see opportunity to shorten this timeline as launch progresses. Turning to the next slide, the thalassemia opportunity presents a major potential growth inflection for Agios. To date, we have received approval of mitapivat for thalassemia in two regions, marketed AQVESME in the US and PYRUKYND in Saudi Arabia.
Our capital efficient global commercial model enables us to focus our investment on the US which presents the most significant revenue opportunity. Outside of the US, we have executed commercialization and distribution agreements with Avanzanite Bioscience in Europe and Newbridge Pharmaceuticals in the GCC.
Given access dynamics, we currently distribute PYRUKYND in Saudi Arabia on a patient-by-patient basis with potential to expand access following national procurement agreements. In Europe and UAE, regulatory reviews remain underway. We anticipate a potential EC decision in the coming months following the positive CHMP opinion received in October 2025.
Across these regions, we see real potential to expand access and deliver a meaningful growth as we scale the launch globally. 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.
Sarah Gheuens - Head - Research and Development, Chief Medical Officer
Thank you, Sarah. Next slide, please. Since we reported third quarter results, we have continued to make progress advancing a robust rare disease pipeline. We received the FDA approval of AQVESME for alpha and mitapivat thalassemia regardless of transfusion burden on December 23, of last year. And as you heard from Tsveta, the US launch is underway with strong reception from physicians.
Following the rise of phase 3 topline data of mitapivat sickle cell disease, we will have our Pre-sNDA meeting this quarter to inform the regulatory path forward.
We continue to advance our more potent PK activator tebapivat in two phase 2 trials and anticipate results in lower risk MDS in the first half of this year and in sickle cell disease in the second half. We continue to advance our early stage pipeline to important decision points this year and are on track to initiate a Phase 1b proof of mechanism trial of AG-181, our phenylalanine hydroxylase stabilizer in PKU patients in the coming months, and reports top-line data from the Phase 1 Healthy volunteer Study of AG-236, our siRNA targeting TMPRSS6 for polycythemia vera in the first half.
Please move to the next slide. Turning to tebapivat , we look forward to understanding more about the potential role of this more potent PK activator in low-risk MDS and sickle cell disease this year. We remain on track in low risk MDS where topline data from the phase 2b trial are expected in the first half of this year.
This study will provide important insights into dose optimization, as well as the potential role of tebapivat in different patient subgroups, including low and high transfusion burden patients, as well as potential applications in later lines of treatment.
In sickle cell disease, enrollment in the phase 2 trial is now complete, an important milestone that reflects the growing enthusiasm for PK activation following the rise of Phase 3 results of mitapivat in this debilitating and deadly disease.
This 12-week double blind trial is designed to further explore tebapivat's potential to deliver meaningful improvements in hemoglobin as well as broader markers of hemolysis. In turn, we see potential for higher hemoglobin response building on the strength of the data established with mitapivat.
Together, these programs underscore the potential for tebapivat to expand our leadership in hematology and address multiple high-value populations where unmet need remains significant.
We have an exciting year ahead of us and we look forward to updating you on our pipeline progress throughout the year. With that, please move to the next slide, and I will hand the call back to Brian for closing remarks.
Brian Goff - Chief Executive Officer, Director
Thank you, Sarah. Next slide. In closing, we have another pivotal catalyst rich year ahead of us. In line with our 2026 strategic priorities, we're focused on executing a high value AQVESME US launch in thalassemia.
In sickle cell disease, we're preparing for our Pre-sMDA meeting for mitapivat this quarter, an important step toward defining our regulatory path. We also expect phase 2 topline data for tebapivat in sickle cell disease later this year, which will give us deeper insight into the potential of higher potency PK activation in this population.
In lower risk MDS phase 2b topline data for tebapivat remain on track for the first half of 2026. And will be a key readout as we assess its ability to drive transfusion independence and broader improvements in anemia. We also anticipate phase 1 top-line data for AG-236 in Polycythemia Vera.
In phase 1b, proof of mechanism data for AG-181 and PKU, two important early-stage programs that expand our reach across hematologic and other rare diseases. Please move to the next slide. As we look beyond 2026, our opportunity set continues to expand. The combined global market potential across our current pipeline indications exceeds $10 billion reflecting both the breadth of unmet need and potential to deliver transformative medicines to patients.
Beginning in 2026, we're focused on delivering a high impact US launch of AQVESME and thalassemia, which we believe has the potential to establish a strong foundation for our leadership more broadly in rare hematology.
Our combination of near-term catalysts, disciplined investment, and a maturing pipeline creates a clear pathway to deliver long-term value. Agios is well positioned for the next chapter of growth while advancing the next wave of innovation across our rare disease portfolio.
Before we move into Q&A, I'd like to acknowledge the dedication of our employees whose unwavering focus and commitment continue to make a meaningful difference for patients with rare diseases. With that, I'd like to open the call for questions operator, please open the line.
Operator
(Operator Instructions).
[Gregory Renzo, True West].
Unidentified Participant_1
Great, thanks. Good morning, Brian and team. Congrats on the quarter and of course another eventful year. Maybe two questions from us on the AQVESME and then on Sickle Cell. First, just on the AQVESME launch, we appreciate all the color you, you're sharing early and get getting.
Patients engaged and prescriptions written just on that translation perhaps on the prescription updates that we are seeing, how do you see that not only translating to treatment initiation but also to revenue recognition, maybe not asking for guidance on early quarters, but any color you can provide on the first quarter and even subsequent early days of the launch with respect to how it pulls through to revenue and then I'd have a follow-up. Thanks.
Brian Goff - Chief Executive Officer, Director
Yeah, thanks, Greg. Very happy to talk about the launch and before Tsveta gets going here, I just want to say I'm really proud of the way the team has executed its early days, but Tsveta is excited to finally have a chance to begin talking about the AQVESME launch.
Tsveta Milanova - Chief Commercial Officer
Absolutely definitely excited, and Greg, as I mentioned in my prepared remarks, we are really encouraged by the early demand that we're seeing with AQVESME. As you mentioned, we reported that we had 44 prescriptions from REMS certified physicians, up to January 30, which is the first five weeks of the launch, and that is fantastic to see.
With regards to your questions, what we expect is to see in the initial quarters, prescriptions and demand to grow ahead of revenues. And the main reason for that is that it takes about 10 to 12 weeks for us to convert prescriptions to treatment initiations and ultimately revenues.
So we anticipate, in Q1, the majority of the prescriptions to turn into treatment initiation, and as the year progresses, we'll expect to see revenues and demands to start tracking, more closely. We get a lot of questions about potential analogs.
So when I think about a Another product which also has a liver REMS that still [sparish] so that's a good analog for you to look at of how the actual revenue trajectory throughout the first year of the launch actually evolved. It's a very different disease, of course, but from a shape of the curve of the revenue, I think it's a good one to look at.
Unidentified Participant_1
Great, thank you that's very helpful and maybe just moving on to sickle cell and tebapivat and of course not to overlook the MDS readout in the in the first half, but you know with enrollment complete in the phase 2 and sickle cell and [exend] color that you've provided, maybe if I may just ask a bit about how you're pegging expectations for what you want to see to get excited about the phase 2 data.
Sickle cell coming later this year. You've spoken about the potency and the higher hemoglobin response potential, but any color that would help to get you excited and how that kind of fits into the larger portfolio relative to mid pivot and the larger sickle cell space. Even thanks so much and congrats again guys.
Brian Goff - Chief Executive Officer, Director
Thanks, Greg, sir.
Tsveta Milanova - Chief Commercial Officer
Thanks Greg. So yes, thanks for the question, Greg. So the phase 2 tebapivat trial that we've just indeed announced full enrollment, is a dose finding trial. So we are looking indeed to explore the doses. We are looking at the hemoglobin response.
It is a standalone phase 2 trial, so our Agios are included as safety assessments. It's, which is different than how the phase 2, phase 3 seamless operational design was for, RISE UP. But obviously we're now in a position that we can leverage data across a PK activation franchise basically, and we're able to use the rise of data to also model what we anticipate a hemoglobin response can lead to for clinical benefit.
So we're very excited about the trial. We think actually the fact that we can announce the enrollment completion also reflects the excitement of the community. The rise of data, announcement really led to a faster enrollment in the tebapivat phase 2 trial, so we are very excited about that.
Operator
[Samantha Simeno, citi].
Unidentified Participant_2
Hi, good morning, and thanks very much for taking the questions and congratulations on all the commercial progress. Just one, follow-up on AQVESME. I'm wondering if you could speak to a bit of the cadence of scripts that have come in since approval, and particularly, are you seeing an increase in the scripts written, since January 30 after the REMS has become fully operational?
And then just a second question. I'm wondering if you could speak to the potential outcomes from the planned FNDA meeting with FDA on the sickle cell disease. You, what are the outcomes that could come out of that meeting? Thanks very much.
Brian Goff - Chief Executive Officer, Director
Thanks Sam. So we, we're going to stick with, the 44 that we have so far for AQVESME, but I think Tsveta could continue to provide color on, the early days of the launch. And so I'll have Tsveta start on that, and then Sarah can speak to, the Pre-sNDA meeting.
Tsveta Milanova - Chief Commercial Officer
Absolutely, Simon, and a reminder, we started basically, engaging and educating physicians and generating demand as soon as the product was approved. So within the first five weeks of the war, and the launch, we've been educating, physicians on the value proposition of AQVESME and the REMS itself.
So we are very encouraged with what we see in terms of demand, in these early stages of the launch. A lot of the things that are happening, and I'm really pleased with the execution of the team are happening as we expected.
So we are seeing prescriptions coming from the transfusion dependent patients and the very engaged, symptomatic, non-transfusion dependent patients who have frequent interactions with the healthcare system.
Which is fantastic, and we see a very healthy dynamics of the launch in terms of the physicians prescribing. We see prescriptions coming from across the country, and a lot of them are in the community setting where the majority of the patients are treated, and I'm really pleased with the progress that the team is making.
Brian Goff - Chief Executive Officer, Director
Great. And then Sarah, the Pre-sNDA meeting and Sam's question about the potential outcomes.
Sarah Gheuens - Head - Research and Development, Chief Medical Officer
Yes, thanks, Sam. So we've guided to the Pre-sNDA meeting in the first quarter of this year. The goal for that meeting is, of course, to gain insight into the regulatory pathways that we can use for mitapivat as stated, we are, of course, going. In with the data package that we can, that we would like to present for full approval based on the data that was generated in rise up with, the strong anti-hemolytic profile that is now, confirming again the anti-hemolytic profile of mitapivat now in a third, hemolytic anemia. With additional strong clinical benefits observed in those hemoglobin responders. And, once we have that meeting, like we are planning to give it an update or when we have the meeting minutes to you guys.
Unidentified Participant_2
Great, thanks very much.
Operator
Alec Stranahan, Bank of America.
Alec Stranahan - Analyst
Hey guys, thanks for taking our questions. Great to see the continued progress for both the commercial and the clinical stage portfolios. Two questions from us, I guess first, what is sort of the main bottleneck in forming that 10-to-12-week prescription to treatment initiation?
Is it getting the patient in for their baseline liver test or maybe something else? And how do you anticipate this shortening over the course of this year? And then second, for tebapivat and MDS. What does good look like on transfusion independence in this lower risk population, and I guess given what you learned from the phase 2a, do you expect you could see activity at the 10 mg dose based on sort of the emerging PK data, or is this maybe more likely at the 15 and 20 mg doses?
Thank you.
Brian Goff - Chief Executive Officer, Director
Thanks, Alex. So we're going to follow the same sequence here. Tsveta gets to talk about the AQVESME being launched, and then Sarah, thankfully we've have a robust pipeline so she can discuss the MDS trial with tebapivat.
Tsveta Milanova - Chief Commercial Officer
Absolutely. So the 10 to 12 weeks is driven by two things. The first aspect is the insurance authorization, which is very standard for any specialty rare disease drug that's not unique to AQVESME.
And the, a lot, most of the patients would need to go through prior authorization, which can take, an average a month, and for some patients, it happens faster. For some patients, it takes longer, but that's One of the main drivers. The second aspect is the requirement for a liver test ahead of the treatment initiation.
So when we combine both of these factors, we anticipate the conversion from prescription to treatment initiation to be on average 10 to 12 weeks. As I said, we, we'll see kind of patients falling on either end of that time frame. And over time, we'll, of course, look to shorten the time from prescription to treatment initiation, on both fronts. We have an excellent market access team, that will be engaging with payers.
So as some of the payers actually put the product on form. January that can be an opportunity for us to move faster through some of the prior authorizations and supporting patients as well as we'll be learning throughout the launch and identify areas to support patients to have an efficiency in their liver testing initially as well.
Brian Goff - Chief Executive Officer, Director
Great. And Sarah, for, tebapivat and MDS, just some of the, what are we expecting and then the different dosing.
Sarah Gheuens - Head - Research and Development, Chief Medical Officer
Yeah, thanks, Alex. And so to your point, we indeed are testing higher doses than the dose that we tested in the phase 2a. So we have a 10 mg, a 15 mg, and a 20 mg dose. So indeed, we are looking, to explore the doses here in this phase 2 to see which dose, would be best.
And then in addition, we are, because It's a heterogeneous patient population. This trial will also allow us to further define patient populations. So we have low and high transfusion burden, plus additional lines of therapy that have been used.
So, it will really give us a lot of insights on where this drug can play a role. Obviously, it's an oral therapy, which, of course, can be very meaningful for a patient population like this because, if patients who have treatment response, it allows them to be really untethered of the clinic.
Brian Goff - Chief Executive Officer, Director
Yeah, it's going to be, it's an exciting year for tebapivat in 2026. We have two catalysts, as we noted. We have, the MDS phase 2b trial in the first half of the year, and then, as we've already discussed, for sickle cell disease, in the second half of this year, we look forward to that phase 2 result.
Alec Stranahan - Analyst
Great, thanks for the color and congrats on the continued progress, guys.
Brian Goff - Chief Executive Officer, Director
Thank you.
Operator
Marc Frahm, TD Cowen.
Marc Frahm - Analyst
Hi, thanks for, taking my question, questions. Maybe just start on ves me with, the rems certified physicians. Just can you maybe talk about kind of where that is from a quantitative perspective, within these first few months, and what do you think that trajectory looks like in terms of number and breadth of, certified physicians over the next, quarter or two as the, as that part of the, ramp really happens, and then I'll have to follow-up on the pipeline. Okay, so we can start.
Tsveta Milanova - Chief Commercial Officer
Yeah, when it comes to the REMS, for in this initial stage of the launch, I'm really pleased, with what we are seeing, and things are happening exactly as we anticipated. Physicians don't see the REMS as a barrier to prescribing, and the patients that we've engaged with, they basically, they don't see it as burdensome given the strong valid proposition of AQVESME and their willingness to consider and initiate therapy.
What is happening with the REMS, initially, a lot of the bigger academic centers and care wells are getting certified. And when it comes to the community physicians, actual certification happens almost simultaneous with the first prescription.
And we'll see, in a way the certification and REMS, progressing simultaneously over time. But as I said, REMS hasn't been a reason, or a reason for not to prescribe. It's the opposite. When physicians have patients that they want to initiate, they're more than willing to start to complete the REMS, which can actually take, one visit. It's a very, quick process.
Marc Frahm - Analyst
Okay, thanks, that's helpful. And then maybe just following up on Sarah's comments about the Pre-sNDA meeting and that the package is really aimed for supporting full approval. I think at other times you've also mentioned possibilities of an outcome of accelerated approval. Is that still something you think is a reasonable outcome, or are you, more confident in.
A full approval then maybe you have been as you've gotten a little deeper into the data and conversations and then assuming accelerated is on the table, what's your latest thoughts on kind of what a confirmatory trial might look like under that scenario?
Sarah Gheuens - Head - Research and Development, Chief Medical Officer
Yeah, so thanks, Marc. So for us, the data package really the benefit risk profile generated in rise confirms a strong anti-hemolytic profile, as I mentioned, and we really see those clinically meaningful changes in the hemoglobin responders. So our view is that benefit risk here is, seen in this trial, and it's a supplemental NDA. Now, as you also know, at Ash recently, the FDA highlighted that hemoglobin can be a surrogate endpoint for sickle cell disease.
So either one of those pathways for us allows us to discuss the data and have that meaningful conversation with the agency. Under any of those circumstances, then there's always the normal filing procedures that, one would have to go through. But we're very, excited about the data as it stands.
Then, in regard to your question on confirmatory trials, obviously, we have, several options that we can discuss in which some of these options have endpoints that have been used before. Some of them are novel endpoints as well, so we're ready to discuss, as needed.
Marc Frahm - Analyst
Okay.
Thank you.
Operator
Eric Schmidt, Cantor.
Eric Schmidt - Analyst
Hey guys, sorry for, any background noise, but, Cecilia mentioned a direct path or clear path to profitability. I was hoping you'd get a little bit more detail on thinking around the breakeven point of, revenue needed to hit that and maybe timelines to profitability. And then were there any sales at all in the GCC countries in Q4?
Thank you.
Cecilia Jones - Chief Financial Officer
So we have, thanks, sorry, we gave the guidance on profitability with PKD and thalassemia regardless of the path forward for sickle cell. Some of us are based case there. We haven't given a specific timing of when that that will happen. We believe that, Tarain is a meaningful opportunity. We're excited about the initial stages of the launch. We also have, as you mentioned, [XUS], being part of that opportunity as well.
And then part of, that profitability path also. Requires us to proactively manage our ops as we navigate the multiple catalyst on the pipeline. We talked about tebapivat, we also have other earlier programs, so we haven't given specific timing on that second GCC and then for GCC, what we've seen, the XUS revenue we saw in Q4 is mostly driven by Europe, and that is. In anticipation of demand, so that's what we guided to an expected decrease, Q4 to Q1 GCC as a reminder today is on an equivalent of a named patient like case by case, so you'll see some consistency quarter over quarter until we get to the point where we have more, broad access negotiated over the next 12 to 18 months or so.
Brian Goff - Chief Executive Officer, Director
Yeah, and we're, and Eric, I'll just add we're pleased with the partner we have in place in GCC with Newbridge. Tsve and I spent some time in Saudi Arabia, late last year and really got a kind of a street level sense about how the team is doing, the enthusiasm from clinicians as well as, even at the Minister of Health level, and you know that's going to take some time to build traction, but I think in the early days we feel quite good about the opportunity.
Eric Schmidt - Analyst
Thank you.
Operator
Emily Bodnar, HC Wainwright.
Emily Bodnar - Equity Analyst
Hi, good morning. Thanks for taking the questions and congrats on all the progress. I guess for the first one, can you give some color on the type of physicians who were initially prescribing a AQVESME and whether they're mainly physicians who've used PYRUKYND in the past or you're getting physicians who are newer to drugs? And then on sickle cell disease, assuming you achieve alignment with the FDA, are you expecting potential approval in 2026? And can you maybe discuss some of the launch preps that you're planning to do this year ahead of approval?
Brian Goff - Chief Executive Officer, Director
Thanks Emily. So, you want to start with AQVESME and the types of physicians in the early days?
Tsveta Milanova - Chief Commercial Officer
Absolutely, as I said, a lot of the early launch dynamics are playing as expected. The team did a fantastic job ahead of the launch, profiling and prioritizing accounts, so the initial prescriptions are actually coming from the physicians we anticipated, to see prescribing.
As I mentioned, Emily, they're primarily the community among, where a majority of the patients are, and these are physicians we've engaged with previously. We don't see that much overlap between PK deficiency and thalassemia, and that's because PK deficiency is an ultra-rare disease.
So there are very few physicians who actually have experience with PYRUKYND through PK deficiency. And as I said, I'm very pleased with the start of the launch. It's a very healthy breath of prescribing that we see across the country. Different physicians are engaged and really trying the product in the patients that they think will benefit the most initially.
Brian Goff - Chief Executive Officer, Director
Great. And Sarah, for sickle cell disease and yes timing.
Sarah Gheuens - Head - Research and Development, Chief Medical Officer
Yes, so Emily, we haven't guided to potential approval dates yet. We are now, the first guidance we have given in this process is our Pre-sNDA meeting anticipated Q1, and then in regard to the launch prep, I will ask Cecilia to come.
Cecilia Jones - Chief Financial Officer
Yeah, so as a reminder, we didn't. And are very similar to how we did thalassemia, we didn't build for sickle cell until we saw the data, and that's what we refer to when we talk about the gated sickle cell, investments. We will, look into that timeline and understand the path, to start, building investment there accordingly.
Operator
Salveen Richter, Goldman Sachs.
Salveen Richter - Analyst
Good morning. This is Lydia on for Salvin. Thanks so much for taking our questions and congrats on the updates. Is there any additional color you can provide on the split between the non-transfusion and transfusion dependent patients, amongst these 44 scripts that have been written, and then given scripts will be the key metric to watch. Do you anticipate third-party services like AQVIA to accurately capture these scripts? Thanks.
Tsveta Milanova - Chief Commercial Officer
So much. Yes. So, the initial prescriptions, as I said, very much as we anticipated, come from a combination of transfusion-dependent patients. Obviously, a large proportion is transfusion-dependent patients, and, a very engaged, symptomatic, non-transfusion dependent patients who are in a, active interaction with the healthcare system.
So when you think about the kind of the evolution over time, as anticipated, I think we'll see initially more transfusion dependent patients, but the scale up of the launch will come from the non-transfusion dependent patients, later on.
When you think about AQVIA, we have a single, specialty pharmacy that distributes the product, so AQVIA will not be the right source for you to look at. It's just the information will not be available. And this is the reason that we're looking to provide you initially with prescriptions, revenue, as well as we gave you the guidance on PK deficiency, so you can see where the growth of thalassemia will be coming throughout the year.
Operator
Tessa Romero, JPMorgan.
Tessa Romero - Analyst
Hey guys, thanks so much for taking our questions this morning. So first one is just on AQVESME. Just can you just quickly touch on initial payer dynamics? Over the first couple of quarters here and remind us of payer mix, just want to make sure that we're thinking about potential free drug the right way. And then second question, a bit of a housekeeping question here. If you are indeed improved in sickle cell disease, how does your SG&A line change? Just trying to think through what you might need to successfully launch a drug in sickle cell. From an expense perspective.
Thanks so much.
Brian Goff - Chief Executive Officer, Director
Okay, thanks, Tess, and Taveta can start on the payer aspects and maybe we could also just remind or gross the net assumptions too. I don't think we, yes.
Tsveta Milanova - Chief Commercial Officer
I'm, so Tess, I will start here. So the payer makes in thalassemia is quite similar to begin efficiency with the majority of the patients being, under the commercial payer bucket. Very similar to PK efficiency in any other drug. Initially, the actual market access and pay authorization through, it will happen through medical exceptions because payers would take time, about six months, six to nine months, to actually start putting the product on formulary.
We have a very experienced market access team that is very familiar of how to navigate the medical exceptions process. And so far, in these early stages of the launch, I must say, as expected, we haven't seen, any big hurdles at all. I think that the valid proposition of AQVESME speaks to itself and the team is doing a great job in terms of those interactions.
Brian asked to kind of to comment on the gross to net, assumptions, given that we don't expect that to be a managed category, very similar pair mixed to peaking efficiency, our gross to net assumptions for thalassemia similar to peaking deficiency 10% to 20%.
Sarah Gheuens - Head - Research and Development, Chief Medical Officer
And then on the SG&A question test and we think about it, so as I mentioned we're going to gate and manage our spend, based on the regulatory discussions and the timing but if you want to think about it is we have an infrastructure that we have built for PKD and thalassemia that we would obviously leverage, but the scale of signal is much bigger, so we would have to scale up those functions that we build, but we have a really nice foundation to, bid from.
Tessa Romero - Analyst
Thank you.
Operator
Luca Scalia, RBC Capital Markets.
Luca Scalia - Analyst
Oh, great. Hi, team. This is Shelby on for Luca, and thanks for taking the question. Could you remind us what's the rationale for dosing higher and lower risk MDS versus the phase two for sickle cell disease? And then maybe one more. Now that we have the label and REMS program for thalassemia, do you expect any read-through to sickle cell and has it changed any internal expectations on the commercial opportunity there? Any color, much appreciated.
Brian Goff - Chief Executive Officer, Director
Thanks. Yeah, I think so we could start with MDS and the rationale for all of, all three of the doses being higher than what we tested in the 2a, and then we'll talk a little bit about REMS and sickle.
Tsveta Milanova - Chief Commercial Officer
Yes, so for the rationale of higher doses, so we originally had a phase 2a with the 5 mg dose based on modeling from the healthy volunteer trials. We learned in that trial that MDS patients metabolize it faster, the drug, and so we pushed the dose higher in the phase 2b to do further dose exploration versus sickle cell disease patients who are exactly the same as healthy volunteers. So that is why we have those dose differences between those 22 indications.
Brian Goff - Chief Executive Officer, Director
And then, and Sarah, you can start on the sickle cell, the question about REMS and read through and Tsveta can certainly comment on how we see it commercially.
Tsveta Milanova - Chief Commercial Officer
Yes, so, as in the sickle cell disease program, we did not have the same observations as we had in thalassemia. So, it is, it's much more like the Pyruvate Kinase deficiency program where we do not have a REMS, as versus thalassemia where we do have a REMS.
So, all of this. Does give us optionality. So our going in position based on the data observed is that that would not be needed and we would propose something more like the PYRUKYND deficiency path. Now, a read through if it would turn out to be a REMS, I'll hand that one over to Sarah.
Sarah Gheuens - Head - Research and Development, Chief Medical Officer
Absolutely. Obviously, sickle cell disease is a devastating disease with high morbidity and mortality. No treatment options, so we see a meaningful commercial opportunity, assuming we have a label in the US, and the team will be ready to execute on it.
We've got, we got ready and executing successfully on the REMS for thalassemia. It gives us a very solid foundation to continue to execute, if we were to have something similar in sickle cell disease as well.
Brian Goff - Chief Executive Officer, Director
Yeah, and I'll just take a moment to say, so Tsveta's team has Continue to navigate through PKD as a launch, which is ultra rare and certainly not the easiest of, launches that began back in 2022 and now we have AQVESME and off to, a really good start in the first month of January. So I feel very confident the team in any scenario will be very well prepared.
So I think that's our last question.
Operator
Yes.
Brian Goff - Chief Executive Officer, Director
Okay then, I will go ahead and close it down. I first, I just want to thank everyone for joining us this morning. It's an exciting time for Agios. As you heard throughout the call, we're entering 2026 with quite strong momentum and really pleased that we're already seeing strong initial progress with the AQVESME launch in the US. We have meaningful clinical and regulatory catalyst ahead as we've talked about, and we'll continue to operate with financial discipline.
These near-term drivers combined with our advancing pipeline, position Agios to deliver sustained growth and long-term value, and we very much appreciate your continued engagement and look forward to updating you on our progress throughout the year. Thanks a lot.
Operator
Thank you. This does conclude today's conference call.
Thank you for participating and you may now disconnect.