Good afternoon, and welcome to the Ultragenyx Pharmaceutical conference call to discuss the U.S. Food and Drug Administration approval of FAYUVI for the treatment of MPS IIIA, also known as Sanfilippo syndrome type A. At this time, all participants are in a listen-only mode. Following the prepared remarks, there will be an opportunity to ask questions. It is now my pleasure to turn the call over to Joshua Higa, Chief of Staff and Vice President of Investor Relations. Please go ahead.
Bringing the U.S. FDA approval of FAYUVI, the first-ever treatment for Sanfilippo syndrome type A. We appreciate all of you making time to join us this afternoon to discuss this important milestone. A press release with details on this announcement is available on our website, along with an updated corporate presentation. Joining me today are Emil Kakkis, Chief Executive Officer and President, Eric Crombez, Chief Medical Officer, and Erik Harris, Chief Commercial Officer. Howard Horn, Chief Financial Officer, is also on the line for Q and A. Before we begin, I would like to remind everyone that today's discussion will include forward-looking statements. These statements involve risks and uncertainties, and actual results may differ materially. Please refer to the risk factors described in our SEC filings. With that, I will turn the call to Emil.
Thank you, Josh, and good afternoon, everyone. Earlier today, the FDA approved FAYUVI, the first-ever treatment for Sanfilippo syndrome type A and our second gene therapy approval in less than a month. This milestone represents our sixth FDA approval overall and further establishes Ultragenyx as a leader in both rare disease medicine and gene therapy. Before we discuss in detail the significance of this achievement for our company and the MPS community, I want to briefly acknowledge the recent outcome from our phase III Aspire study for GTX-102 for Angelman syndrome. This was truly disappointing for the company and for the Angelman community. We expect to provide a more comprehensive update by our next quarterly financial results call. We will address your questions on the Angelman results and our expense management plans in greater detail at that time.
For today, we are going to focus on the FAYUVI approval and what it means for children and families with Sanfilippo syndrome type A. Sanfilippo syndrome type A is one of the most heartbreaking diseases I have encountered in my career. These children often appear healthy early in life. Then by age two to six years old, as the disease progresses, they gradually lose their ability to learn, to communicate, and to engage with the world around them. After a period of hyperactivity and altered behavior, the children slow down. As family watch, skills disappear one by one, leading to a bedridden state. The children eventually die from this devastating disease, usually as teenagers. Until now, families and clinicians have had to face this diagnosis without any approved treatment with the potential to stop or slow this inevitable decline.
We're here today because parents, advocates, clinicians, researchers, and organizations across the broader MPS community refused to accept that reality. They raised awareness, funded research, participated in clinical studies, and never stopped fighting for their children. Now, thanks to their perseverance, families receiving a diagnosis of Sanfilippo syndrome type A can have hope that their children's future may look different. Ultragenyx was founded to pursue diseases that others overlooked and deliver treatments where none existed before. In less than one month, we've now achieved our consecutive gene therapy approvals for two severe rare diseases, demonstrating not only the strength of our science, but our ability to translate innovation into approved medicines for patients. Even though Ultragenyx was not originally working on Sanfilippo syndrome, we received a call from Abeona CEO, Vish Seshadri.
When funding constraints arose despite positive clinical data, Abeona made the pivotal decision to out-license the asset to Ultragenyx, ensuring this vital treatment reached the finish line for patients. When we picked up the program, our team found a way to make it work relentlessly and courageously, taking on the task, making sure the product on hand was able to treat kids and getting the program to a BLA filing. It has not been an easy road for us either, but we are gratified that all of this work has enabled us to bring forth the first approved treatment for Sanfilippo type A. Developing new therapies is only one part of our mission. We've also believed that approval only matters if patients can actually obtain treatment, and we are committed to helping eligible families within the U.S. access FAYUVI as quickly as possible.
We also know and have gotten urgent calls for treatment from families elsewhere in the world, also in great need, and we will work on finding a way to treat some patients globally while we seek approval in other regions. I'll now turn it to Eric Crombez to review the clinical data and Erik Harris to discuss our commercial launch preparations.
Thank you, Emil. FAYUVI is indicated for the treatment of neurologic manifestations of mucopolysaccharidosis type IIIA or Sanfilippo syndrome type A in pediatric patients with preserved neurodevelopmental function. As Emil noted, this is a rare and fatal lysosomal storage disease that primarily affects the brain and is marked by neurodegeneration beginning in early childhood. The disease is caused by an enzymatic deficiency, which results in the accumulation of heparan sulfate and progressive damage to the central nervous system. FAYUVI is a single-dose AAV9 gene therapy designed to directly address this underlying enzymatic deficiency. Conceptually, this gene therapy provides the ability to produce fully functioning enzyme in some cells in the brain to break down heparan sulfate. These cells will then secrete the enzyme that can cross-correct other brain cells, resulting in a decrease in heparan sulfate substrate levels throughout the brain.
The BLA was based on data from the phase I, II, III Transpher A study and long-term follow-up demonstrating improvements in key developmental domains compared with natural history, along with substantial and durable reductions in CSF heparan sulfate. Clinical data now extend to nearly eight years of follow-up. FAYUVI was generally well-tolerated and maintained a favorable safety profile. The most frequently reported treatment emergent adverse events were elevation in liver enzymes, which were mostly mild or moderate. While we originally submitted FAYUVI for accelerated approval, the agency recognized the robustness of our clinical data package during the review and granted standard full approval rather than accelerated approval. Importantly, this approval covers the entire pediatric age range and reflects the deep understanding by the FDA of the unmet need for children and families affected by this disease.
Over time, we expect that children will be diagnosed earlier through newborn screening, enabling the option for early treatment prior to the accumulation of heparan sulfate and irreversible damage to the central nervous system. As with all of our therapies, we will monitor clinical trial patients and an additional cohort of commercially treated patients in our disease monitoring program through 10 years of follow-up. The totality of evidence generated throughout development gives us confidence in the potential of FAYUVI to meaningfully alter the course of this devastating disease. With that, I'll turn the call over to Erik.
Thanks, Eric. First, I'd like to acknowledge what a rare privilege it is to have the opportunity to launch two drugs in a month, impacting the lives of patients with significant unmet needs. The approach you heard me reference a few weeks ago, understanding the need of patients and caregivers first, remains our guiding principle for this second launch. Families with children that live with Sanfilippo syndrome type A understand that this disease is progressive and relentless. Every day matters to preserve precious neurologic function, and each day without treatment risks the potential loss of critical skills and abilities. That understanding has shaped our preparation. We are fortunate that both GENGLYCOS and FAYUVI fall within our inborn errors of metabolism franchise. So there are significant synergies between our preparations for both gene therapy launches.
Based on extensive pre-approval engagement with both Medicaid programs and leading commercial plans, it is clear that payers understand the devastating nature of Sanfilippo syndrome type A and the importance of treating as soon as possible. Beyond the clinical impact, payers recognize that the lifetime cost of care for a child with Sanfilippo syndrome type A, who can spend years in a bedridden state, can exceed $8 million, and that this burden grows as the disease advances. We set the U.S. per patient wholesale acquisition cost of FAYUVI at $3.95 million as the first and only one-time gene therapy treatment for this ultra-rare, progressive, and fatal neurodegenerative disease with the potential to slow or stop its irreversible decline. Consistent with our expectations for GENGLYCOS, we expect that access in the initial phase of launch for FAYUVI will flow through single-case agreements.
Our UltraCare program has a proven history of helping patients and families navigate access to therapies and overcome potential barriers to care. As I shared at the approval of GENGLYCOS, we have expanded that offering to include dedicated gene therapy guides who will help families navigate insurance coverage, assist in obtaining treatment support, and answer questions about treatment process. Treatment will be provided through a national network of qualified treatment centers selected for clinical expertise and experience in gene therapy administration. The network is highly synergistic with our footprint for GENGLYCOS, with many centers planning to offer both treatments. A list of QTCs will be available on fayuvi.com once that website is live in the coming days. As with GENGLYCOS, we have established relationships with the treating community.
Like families, providers understand that time is of the essence for these patients and approach treatment decisions with a strong sense of urgency. We are expecting fairly rapid requests for treatment. FAYUVI is manufactured entirely within the U.S. at our gene therapy manufacturing facility in Bedford, Massachusetts, and at Andelyn Biosciences in Columbus, Ohio. We believe we have adequate commercial supply to meet initial demand and will continue our efforts to scale manufacturing over time. We expect that the commercial product will be ready to ship to QTCs in approximately 30-60 days, consistent with the expectations we shared for GENGLYCOS. This is now our sixth commercial approval and second gene therapy launch. The infrastructure, capabilities, and experience we have built in commercializing rare disease therapies are highly applicable across our entire portfolio of approved medicines, with purposeful alignment built into our approach for FAYUVI.
We have been preparing for these two launches for months, and we are excited to begin delivering this treatment to patients. With that, I'll turn it over to Emil.
Thank you, Erik. This approval carries special personal meaning for me, having worked on treatments for MPS diseases for more than 30 years. For the first time, families affected by Sanfilippo syndrome type A have an approved treatment option. After years of advocacy, scientific innovation, and unwavering determination from a remarkable community, we have reached a milestone that many once believed might never come. Now the work begins to treat as many patients as we can, as promptly as we can. For Ultragenyx, today's approval further values the vision we've pursued since our founding of delivering first-ever medicines to patients with serious, rare, and ultra-rare diseases, regardless of scientific or commercial complexity. The approvals of both FAYUVI and GENGLYCOS demonstrate the strength of our platform, our ability to execute, and our commitment to leading the future of rare disease medicine.
The company received a priority review voucher upon FAYUVI approval, just as we did for GENGLYCOS. The final delivery of this therapy did not come without tremendous difficulties during its development, and we hope this approval revitalizes investment in other ultra-rare gene therapies. Therapy was developed by Haiyan Fu and Doug McCarty during their tenure at Nationwide Children's Hospital and was licensed to Abeona. We thank Dr. Haiyan Fu, her laboratory, the development and leadership team at Abeona, and so many patients, families, and investigators that worked tirelessly through so many obstacles over the many years to lead us to this moment of shared success. We are honored to stand alongside them, and we are committed to ensuring this approval is only the beginning. With that, we can open the line for questions. Operator, please provide the Q and A instructions.
Thank you. We will now be conducting a question-and-answer session. If you would like to ask a question, please press star one on your telephone keypad. A confirmation tone will indicate your line is in the question queue. You may press star two if you would like to remove your question from the queue. For participants using speaker equipment, it may be necessary to pick up your handset before pressing the star keys. We ask that you please limit yourself to one question and one follow-up. Thank you. One moment while we pull for questions. Our first question comes from Yigal Nochomovitz with Citi. Please proceed with your question.
Hi. Great. Thank you. And congratulations, Emil and team. Very nice to see this. I guess I just wanted to probe a little bit more, if I may, on the label language with respect to preserved neurodevelopmental function. Can you just drill into that a little bit more? What does that mean? How is that exactly defined in terms of a Bayley score or specific retained skills or just physician/caregiver judgment? Thank you.
Yeah, I think a good question, Yigal. And one of the really important pieces of this story is to let doctors practice medicine. I think the FDA were very sensitive to the fact there is a range of patients who might want to get treated, and they offered something more general about this. It does not say neurocognition, so it is not talking Bayley scores. It is neurodevelopmental, and what they are saying is they have some preserved function, meaning, in our interpretation, if someone is bedridden and unresponsive, that is someone who does not have preserved function. So it is leaving open the definition of what a doctor and parent wants to do with regard to level of function. Some preserved function, meaning they are able to respond or have some ability to participate in life.
I think it is really important that it not be Bayley and that Bayley is not part of it, nor part of the discussion. I think they offered an open-ended view of it, but I think we would all agree that someone who is at end-stage disease is not a good candidate for gene therapy, and the goal is to treat as young as possible. This issue is more of an issue at the start because as time goes on, we should be newborn screening and treating kids before they are age two, even before age one. We have some kids treated at six months who have done really well, and I think that is when we got to get to. Right now they have offered something broad in terms of preserved neurodevelopmental function and did not set any testing standards on what that means.
I think it was very thoughtful of the FDA, and I appreciate their thinking through of letting doctors and patients decide for themselves what is the right decision on treatment.
Okay. Great. If I could just do one follow-up for Howard or for you, Emil. Could you comment on the timelines to monetize the two PRVs, which are important for your cash position? Thank you.
I will let Howard answer that one.
Yigal, thanks. Same answer as the last time. We will monetize both of them. We will monetize the first one expeditiously, and the second one when we think the time is right.
All right. Well, congratulations again. Thanks.
Yeah. Think it's a good market for them, so we expect to be an important addition to our cash position at the company.
Yeah.
Puts us in a very good position. Next question.
Thank you. Our next question comes from Anupam Rama with JP Morgan. Please proceed with your question.
Hey, guys. Thanks so much for taking the question, and congrats on the approval here. The press release talked about shipping to qualified centers in the next 30 - 60 days. Can you talk a little bit about how many centers of excellence we're talking about here that are equipped for infusions today, and how that could grow over time? Thanks so much.
Sure. And I think Erik Harris can provide a little bit on that. Are you able to do that, Erik, on the numbers? But there's a few dozen of them already, but it's growing. Erik Harris, did you want to answer?
Yeah, sure. Overall, there are about 120 or so centers that focus on these areas. But with regards to qualified treatment centers, we have over 25 under contract now, and they are growing daily. I get updates almost every day it seems like now, with us adding another treatment center. As consistent with what I said during the GENGLYCOS call, we expected to get to 40 or so qualified treatment centers by the end of the year. More than enough to meet the initial demand that we're expecting for both products. And most of the sites are dual sites for both GENGLYCOS and FAYUVI.
Congrats again on the approval, guys.
Thank you.
Your next question comes from Yaron Werber with TD Cowen. Please proceed with your question.
Good afternoon, management. Thank you so much for taking the question, and congrats on the approval. It is an important day for patients. This is Steven Ionov on for Yaron. Among the 3,000 - 5,000 patients that you have identified as prevalent within the Sanfilippo type A community, what, based on the neurodevelopmental stage, would you consider the pool that would be most accessible, or I suppose, the first logical treatment candidate for FAYUVI? And how many of those patients are identified and present at current qualified treatment centers? Thank you very much.
Yeah. So right now we're aware of, in the U.S., around 300 - 400 patients that are potentially within the range. With regard to the development function, obviously, people don't post that routinely about their patients. But generally, when patients reach 10, 11 years old, they start to be at the end of their period. They become bedridden often as teenagers. So we're talking about patients generally are going to be younger than that, probably less than 10 or 11. More likely, the average age will be more like five. But we'd expect there might be patients up to age 10 that might be still in function.
We haven't precisely put down the list yet, but there's a lot of patients to treat already around, and our hope is to treat as many of the ones that are prevalent now, and hopefully to enhance the diagnosis of the young ones where the most good can be done, before age two or really before age one. But we don't have a precise number, but that gives you at least enough idea for the U.S. right now.
Got it. Just to confirm that 300 - 400 within the range, that range you're referring to is the range of ages that you were just speaking of, right?
Yeah, it's about that. Yes.
Thank you, and congrats again.
Thank you. Our next question comes from Maury Raycroft with Jefferies. Please proceed with your question.
Hi. Congrats on the update, and thanks for taking my question. For Erik's comment around the expectation for rapid requests for treatment, is there more color on that you're providing? What could initial demand look like? Is there more perspective on what that could be for what patient demand for 2026 maybe through 2027 could look like?
Well, I'll let Erik answer in a second. We're generally not going to put out forecasts or guidance on what's going to happen in the first six quarters. That's just been our habit. We don't want to overstate and create an issue. We are going to work promptly to get as many as we can. We have enough treatment centers up, and they continue to add them to service patients. We do think the drug is going to do well. That is, we think that there's a higher C to treat, and we have product available, and we expect to do well. Right now, Maury, I don't think we're going to give any precise predictions on the ramp yet.
But I realize that's a very important issue for gene therapy because there have been some ones that have done extremely well and some that have done very poorly. I don't know, Erik Harris, is there any other color you would provide on that?
Nothing else to add at this particular time. But other than that, there's very strong interest from patients and the patient community.
Got it. That's helpful. And maybe just one follow-up for the price. Do you expect that some payers are going to require an outcomes-based reimbursement arrangement? And what could that look like? Or is this something that you're offering proactively to payers?
I think we expect in May. I don't know, Erik, if you want to comment on the OBAs.
We'll be prepared to engage payers regarding OBA if that is something that will get them more comfortable with providing reimbursement. But we're not expecting to have to do that with the majority of the payers.
Got it. Understood. Congrats again. Thank you.
Thank you.
Thank you. Your next question comes from Kristen Kluska with Cantor. Please proceed with your question.
Hi, all. Congrats on this approval and appreciate you taking this program forward so that these patients now have an option. I wanted to ask on patient identification efforts. I remember a couple years ago at World, one of the themes was looking at different facial recognition features for different MPS patients to help identify it, and that was before this AI wave. I am curious if there are ways you can be creative about trying to find more patients.
Yes, I think there are. I think the facial recognition for Sanfilippo is probably the weakest feature because they have the least effect on the facial features, where for other MPS, there is much more bone effect and therefore more facial effect. The big thing really is the early screening for developmental delay, any developmental delay or anything to help identify these cases before they have gone too long. I think the challenge with that, of course, is that once some developmental delay, that means they are already having some brain effect going on. The truth is that the best thing is to work on newborn screening and to get it advanced into newborn screening. There is already MPS I and II newborn screen or on the RUSP. We need to get this added.
We have been supporting work to have the same type of enzyme assay that is used for those others to be used for screening, and we think that needs to get implemented. I think the RUSP process needs to change. The committee has come apart right now, but Secretary Kennedy has been nominating, putting things on the list on his own without an advisory committee. We need to get this on that, and we need to get it implemented across the U.S. so these kids are getting treated when they are six months old, which I think will give us the best effect. So there are some ways to screen symptomatically, but optimally, it has got to be newborn screening, and we have got to press for it, and we are actively doing that. Okay, next question.
Your next question comes from Salveen Richter with Goldman Sachs. Please proceed with your question.
Hi, this is Lydia on for Salveen. Thanks so much for taking our question and congrats on the approval. Could you just speak to the overlap with the prescriber base with your existing commercial franchise and also the sales force that has been deployed for GENGLYCOS? Thanks so much.
Certainly. There is a big overlap. The majority are medical geneticists that make the diagnosis, and so there is a very large overlap. I can let, in a moment, Erik, who wants to add a little more about that overlap. So medical geneticists, which is what I'm trained as, make the diagnosis commonly. There are some cases, areas where a pediatric neurologist might make the diagnosis for Sanfilippo, where there might not be a medical geneticist. So those are a couple of the specialties. I don't know if you have anything else to add, Erik Harris, on that.
Yeah. You asked the question about our current field team. As stated with the GENGLYCOS launch, this falls right into our inborn errors of metabolism franchise. So the same team that has been calling on these centers for years now for both MEPSEVII and DOJOLVI will also continue to call on these same institutions, and we estimate probably 75% or more overlap. So this will be a highly leveraged franchise that has established relationships with many of these doctors already.
Thanks so much.
Your next question comes from Ellie Merle with Barclays. Please proceed with your question.
Hi, this is Tejas on for Ellie. Thanks for taking our question. As you begin to launch both of these two therapies in the U.S., can you remind us what key metrics you will provide for the launch, like start forms or something similar? Then in terms of the treatment timeline, how should we think about the timing between start form and patients eventually receiving drug?
Okay. With regard to, we will be talking about how many QTC centers we have up and running and ultimately the number of patients that have been treated. We could do start forms, but I guess it is really treated as probably more an accurate sense. The second question?
Time to treatment, identify to treatment.
Time to treatment will obviously be evolving over time. In the beginning, they are all exceptions, and we are waiting for their policies. Erik, do you have anything to say, I think, about time to treatment? Obviously, it matters a lot for Sanfilippo, so we do not want it to take a long time. We need to drive this along. We have told all the payers, by the way, that it needs to be treated like ZOLGENSMA for SMA. Erik, any thought on time to treatment?
Yeah. We have several patients in process right now as they work and consider treatment. In fact, we have already received some initial start forms for GENGLYCOS. As we stated, we will work with the patient and the caregivers through the reimbursement process, and expect these patients to be available within 30 - 60 days, and that is on track. I think somewhere in that timeframe, we should have our initial treatment of patients for both therapies.
Something like 30 - 60 days to time to treatment.
Yeah.
I think with FAYUVI, we are going to want to, as time gets going, we will want to make it as tight as possible. We have actually set up our systems and the testing that needs to happen and other things to make sure we can move this along as promptly as possible. Thank you for the question. Let us go on to the next question.
Your next question comes from Joe Schwartz with Leerink Partners. Please proceed with your question.
Thanks, and congrats on the approval. Given the release frames global access as a longer-term goal, I was just wondering what is the timing for other territories? In particular, where does the MAA in the EU stand? Can you remind us of the Abeona economics in terms of things like the approval milestone, if there is one, royalty rate, and is there any sharing of any proceeds from a PRV? Thanks.
Yeah, we can comment. I will let Howard comment on some of that in a moment. Regarding global access, our plans are we are going to file in a number of countries shortly or have, and we will probably put out a little more detail a little bit later. We expect to work toward Europe particularly soon. We are also seeing many named patient inquiries from the Middle East and other places for FAYUVI. So we would also expect to support named patient treatment outside the U.S. in the meantime, while we are also pursuing formal filings and approvals.
Yeah, I will take the Abeona economics. There is more on this in our corporate deck and on our other filings, but the short answer is, no sharing of PRV. The commercial milestones, I think range up to about $30 million or so, and there is a mid to high single-digit royalty.
Thank you.
Your next question comes from Ben Burnett with Wells Fargo. Please proceed with your question.
Hi. Hello. This is Tian Xi calling in for Ben. Congratulations on approval. Understanding that the target prescribing physician is largely kind of same, but can you please just quantify how much of maybe expenses that will be associated with this launch? Thank you.
Sure. Well, we're actually leveraging almost everything that's been gone, and the few things we added for GENGLYCOS will be used here as well. So it's actually a relatively modest incremental spend for us, because the field team was already selling DOJOLVI and MEPSEVII, and that team's already out there, and maybe there's a few people, but I would say the expense of being relatively modest. We do have a gene therapy treatment team, like a physicians to help manage the ongoing treatment. But we already set that up for GENGLYCOS, and they're managing both. So the true incremental expense would be modest, and it's going to really leverage a lot of what we've done before. So we think this will help it become accretive to us more rapidly with that base cost already being covered.
Thanks, and congrats again on approval.
Thank you.
Your next question comes from Maxwell Skor with Morgan Stanley. Please proceed with your question.
Great. Thank you very much for taking my question, and congratulations. I was just wondering if you can provide any insights into gross to net, particularly in the early stages of the launch. Thanks.
We can. Sometimes there are obviously a number of government discounts. Howard or Erik, you want to comment on that?
Yeah. So what Erik had said earlier is that our WAC price is going to be $3.95 million. And what we've shared in the past is that our net range is $2 million-$4 million, which of course may not be all that insightful because it includes the WAC price. We can help sharpen it maybe later, but that at the moment is what we've shared.
Great. Thank you.
Yep.
Your next question comes from Jack Allen with Baird. Please proceed with your question.
Hi. Thanks, everyone. Good afternoon. Congrats on the approval. This is Chris on for Jack. Just piggybacking off that last question, commercial opportunity, I know it's early days, but just back of envelope math, it seems like you're— This projection could be a billion-dollar drug, just your thoughts on that. And then just one on CMC. I know you made some alterations to that in response to the CRL to UX111. And just anything from those changes that you think might be able to help GENGLYCOS and FAYUVI. Thanks.
Well, on the second one, we do still finish in the same place, so the changes we made help work with each other in terms of CMC. We didn't change the process at this point. The process being run is a relatively smaller scale process. We'd opted not to try to change process in the middle here, but we will probably expect to scale the process further as time goes on, as we move ahead. We haven't talked to the commercial opportunity. I would say we are not thinking of it as a billion-dollar opportunity. I think that would be a reach. But we do think it's a substantial opportunity, and as we can say very clearly from history, whatever your in gene therapy, that the size of the opportunity is not necessarily just the number of patients exactly, but it's the urgency and how many get treated.
I think in Sanfilippo, the urgency will be high, though the population relatively smaller, we will actually see a lot of these patients will want to get treated and get treated quickly. They're not going to wait and see. So I do think it's going to be a very reasonable opportunity, probably larger than what people think, but I don't think that it's a billion-dollar opportunity. I wouldn't want people to believe that.
Jack, maybe just to pull up. Let me pull a few things together that have been answered in different parts of today. So 3,000-5,000 patients in commercially addressable markets, and we have talked about maybe a quarter of those in the U.S. WAC price, we have talked about a net price. We talked about WAC of $3.95 million and net somewhere between $2 million and $4 million. We have talked about the fact that we have a preexisting field force, that does not really need to be augmented much to get this out there. And we have talked about a PRV coming along with it. So those are building blocks of the model that we have shared with folks.
Got it. Thank you, and congrats again.
Thank you.
Your next question comes from Laura Chico with Wedbush Securities. Please proceed with your question.
Thank you very much. Congratulations, Emil and team, on the approval. I guess just one, and I do not know if I should direct this towards Erik a little bit, but I am trying to better understand what is the capacity of these centers to treat? I believe I heard about 40 centers, but I guess I am trying to understand. Obviously, there is a high urgency to get folks in the door here, but there is also a pretty complicated cases. Just wondering if you could expand on what happens to get centers up and running and what that capacity looks like. Thank you very much.
Well, I think Erik had told you we had 25. We are adding them regularly. In fact, some of the first GENGLYCOS patients were at new centers. We actually have a whole team set up to set up and train centers and train them wherever they are. We are not going to be stiff about requiring only certain centers. We made them to be quick as possible, but based on payer issues, region, state issues, we have to make sure to be adaptive, and we are planning to be. I do not think capacity of the centers to treat patients is going to be a limiter in our ability to commercialize at all. I think we have got plenty of QTCs, and we will add them as needed wherever they are needed to make sure we are treating everyone that needs to get treated.
Right now, I do not think that the QTC capacity is going to be an issue. I do not know if you had anything else to say, Erik Harris, on it.
That is right. I mentioned we have grown more than 25 now, expect to get up to 40 or so by the end of the year. We will keep adding as we move forward with expanded demand. I do not want you to think we are going to cap the number of treatment centers at 40. We will continue to expand as needed.
Yeah.
Thank you very much. Congratulations.
That expansion may be. Yeah. Good. Okay. Thank you, Laura.
The last question comes from Ram Selvaraju with H.C. Wainwright. Please proceed with your question.
Hi, this is Jade on for Ram. Thank you so much for taking our question, and congrats on the two gene therapy launches. Could you just discuss quickly, what real world evidence data is likely to be collected following the launch, in your patients?
Yes. Well, real world evidence is talked about a lot. We actually believe in another model we call disease monitoring program model, which is a fully sponsored model where we collect accurate, high-quality data and support the doctors and the patients in getting that data, which will allow us to do it with great precision and quality with limiting missing data. The FDA has accepted the DMPs now for all six of our programs that have been approved as a single post-marketing commitment in which we do all the clinical work. It is a different model than real world data, but we will collect data in our programs for up to 10 years. But all the patients in the program are on commercial drug. So they do not get drug as part of this program. They get monitored, or they get testing done by it.
The difference then with real world data, instead of using electronic records and other sources to pull up information, we are able to quantitatively, more like a study, measure individual data. There is no doubt that claims data or other real world data will be a supplement to it, but it is not our main focus. We definitely think there is an opportunity to use real world data. It just will not be the main thrust of our approach to monitoring patients long term.
Great. Thanks for explaining that. Just quickly, could you discuss the mild label restrictions on liver function, particularly as it pertains to AAV therapies?
Sure. I will let Eric do that. I think the general view is that all AAVs go to the liver, so you do not want to have a liver that is highly injured so that you do not hurt them. But Eric, do you want to say anything about that? Eric Crombez.
Yeah. Right. Thank you. Yeah. So certainly no restrictions in the indication. We always, as Emil said, want to dose patients with relatively healthy livers. But that is not an issue here. That was not a screening issue or something that we really encountered while we were enrolling these trials. So we do not expect it to be an issue at all in the commercial setting either.
Yeah. The Sanfilippo patients do not have liver injury. There are some disease where there is, but they usually do not have significant liver injury. Thank you for the question.
Thank you so much.
Last question. Operator, can you hear us?
Yes, the last question comes from—
We can hear you, Josh.
The last question comes from—
All right. I think we have the last question coming from Sami Corwin at William Blair. Sami, go ahead.
Hello, this is Josh on for Sami. Congrats on the approval. We were wondering what launch metrics the company plans on sharing, and how soon should we expect those updates? Thanks.
Yeah. We're planning to. We'll tell you about how many QTCs and how many patients have been treated for both diseases. That will be it. We'll probably be doing that on our quarterly calls. It was our expectation. At points where we're providing revenue numbers, we'll provide revenue numbers. But those will be the metrics right now. I think those are the ones that are important. It should give you a feel for how things are going. By the first call that's coming here, I'm not sure there's a lot to be said yet, but we do expect in every quarter to provide qualified treatment centers, number of patients treated, revenue numbers for each program. Okay? Very good. Thank you.
This now concludes our question and answer session. I would like to turn the floor back over to Joshua Higa for closing comments.
Thank you. This concludes today's call. Please reach out to us at ir@ultragenyx.com if you have any additional questions. Thanks.
Ladies and gentlemen, thank you for your participation. This does conclude today's teleconference. Please disconnect your lines and have a wonderful day.