Good afternoon, and welcome to Omeros Corporation's conference call. Today's call is being recorded at the company's request, and a replay will be available on the Omeros website. I'll now turn the call over to Jennifer Williams, Investor Relations for Omeros. Please go ahead.
Thank you, and good afternoon, everyone. Before we begin, please note that today's discussion will include forward-looking statements regarding Omeros' operations and assets, including its newly approved drug, YARTEMLEA. Forward-looking statements regarding YARTEMLEA include, without limitation, expectations and projections regarding anticipated demand, manufacturing capacity, commercial sales, reimbursement, and development, and additional indications. These and other statements on today's call reflect management's current expectations and beliefs as of today and are subject to risks and uncertainties that could cause actual results to differ materially. For a detailed discussion of these risks and uncertainties, please refer to risk factor sections in our most recent annual report on Form 10-K and our subsequently filed quarterly reports on Form 10-Q. With that, I'll now turn the call over to Dr. Gregory Demopulos, Chairman and CEO of Omeros.
Thank you, Jennifer, and good afternoon, everyone. Thank you for joining us. With me today are David Borges, our Chief Accounting Officer, Nadia Dac, Omeros' Chief Commercial Officer, Dr. Andreas Grauer, Omeros' Chief Medical Officer, and Dr. Cathy Melfi, our Chief Regulatory Officer. We're also fortunate to have with us today three leading stem cell transplant experts: Dr. Rafael Duarte, Head of Hematology and Hematopoietic Transplantation, Hospital Universitario Puerta de Hierro Majadahonda, Dr. Miguel Perales, Chief of the Adult Bone Marrow Transplantation Service at Memorial Sloan Kettering Cancer Center, and Dr. Alessandro Rambaldi, Professor of Hematology, University of Milan, and Head of Hematology and Bone Marrow Transplantation at Papa Giovanni XXIII Hospital. Narsoplimab, commercialized under the brand name YARTEMLEA , received FDA approval on December 23, 2025. This approval establishes several important firsts.
YARTEMLEA is the first and only therapy approved by FDA or any regulatory authority for the treatment of hematopoietic stem cell transplant-associated thrombotic microangiopathy, or TA-TMA. TA-TMA is a life-threatening complication of stem cell transplantation, and even among those who survive, morbidity is often severe and chronic, including kidney failure requiring long-term dialysis. YARTEMLEA is also the first and only FDA-approved inhibitor of the lectin pathway of complement and the first and only approved inhibitor of MASP-2, which is the effector enzyme of that pathway. This approval marks another major milestone for Omeros, our second FDA-approved product following OMIDRIA, which we successfully commercialized for use in cataract surgery. YARTEMLEA 's approval underscores our track record of translating cutting-edge science into approved medicines addressing significant unmet needs. The YARTEMLEA label reflects the full scope of disease sought by Omeros.
Specifically, all TA-TMA patients, both standard risk and high risk, are included in this indication, and the label covers both adult and pediatric patients two years of age and older. FDA approval was based on our 28-patient single-arm pivotal trial supported by a 221-patient expanded access program. Collectively, these data form the clinical foundation for approval. Importantly, YARTEMLEA achieved approval with a differentiated safety profile. While other agents, including C5 and C3 complement inhibitors, often used off-label in TA-TMA, YARTEMLEA 's approved label carries no box warning, no risk evaluation and mitigation strategy, or REMS, and no vaccination requirement. The efficacy data and important safety information for YARTEMLEA are detailed in the prescribing information and can be found on the YARTEMLEA website. I would encourage clinicians to review the full label. Turning to efficacy, YARTEMLEA demonstrated clinically meaningful benefit.
Efficacy was assessed by TMA Complete Response, defined as improvement in key laboratory markers, platelet counts, and LDH levels, together with either improved organ function or transfusion independence. Complete response was achieved in 17 of 28 patients, or 61%, in the pivotal TA-TMA study, and in 13 of 19 evaluable patients, or 68%, in the expanded access program. Importantly, across the pivotal study and the expanded access program, 100-day survival from the time of TMA diagnosis was 73% and 74%, respectively, based on all-cause mortality. While the approved label includes all TA-TMA patients, it's important to note that all patients in these studies met international harmonization criteria for high-risk TA-TMA, a population with a high risk of death and historically poor outcomes. In peer-reviewed publications, treatment with YARTEMLEA was associated with a three to four-fold lower risk of mortality compared with an external control cohort.
In the expanded access program, YARTEMLEA was used both as first-line therapy and in high-risk TA-TMA patients who had failed or discontinued one or more prior regimens, namely off-label C5 and C3 complement inhibitors and/or defibrotide. Even in these refractory high-risk patients, YARTEMLEA delivered 50% one-year survival compared with historical one-year survival rates of less than 20%. The favorable safety profile of YARTEMLEA , including no box warning, no REMS, and no required vaccinations, stands in contrast to therapies historically used off-label in TA-TMA. Two recent publications underscore why this matters. In a pediatric TA-TMA cohort reported from Emory University, use of the terminal complement blockade with the C5 inhibitor eculizumab was associated with an eight-fold increase in infection risk and a six-fold increase in infection-related mortality. And an adult, apologies for that interruption. We're not quite sure where that originated.
But to continue, an adult reported by Memorial Sloan Kettering Cancer Center, the C5 inhibitor eculizumab was associated with a five- to six-fold increase in the risk of death driven by higher non-relapse mortality, with deaths predominantly due to infection. Against this backdrop, there has been strong anticipation within the transplant community for an FDA-approved therapy specifically for TA-TMA. It was in this setting characterized by a clearly defined unmet need, a highly favorable benefit-risk balance, as well as strong interest from clinicians that we initiated the commercial launch of YARTEMLEA on the 2nd of January. Our entire commercial team has been hired. On Friday, our fully trained field force of account managers and directors, market development managers, access lead, and medical science liaisons began contacting U.S. transplant centers across the nation, detailing the efficacy and safety benefits of YARTEMLEA and preparing the centers to place orders.
Our focus is to educate the entire transplant care team, including the transplant physicians, nurses, hospital pharmacies, and reimbursement teams, for seamless and timely access to YARTEMLEA . TA-TMA can occur after both autologous and allogeneic stem cell transplantation, but it occurs most commonly following allogeneic transplants. Approximately 11,000 allogeneic transplants are performed each year in the U.S. and another 20,000 annually in Europe. Recent studies estimate that TA-TMA develops in up to 56% of allogeneic transplant recipients. TA-TMA, though, is still thought to be frequently underdiagnosed, and time to diagnosis can be a key factor in outcomes. There are 175 stem cell transplant centers across the U.S. The top 40 centers account for about 60% of procedures, with the top 80 centers representing approximately 80%. These 80 centers are our initial priority, and there are strong YARTEMLEA physician supporters at each.
We are prioritizing centers with the greatest transplant volume and established TA-TMA expertise, and we expect early utilization to concentrate in these programs. We expect that our recently completed YARTEMLEA manufacturing campaigns, together with existing inventory and a drug product shelf life of five years, provide sufficient drug supply to meet commercial demand into late 2029. Drug product packaging, including the printed FDA-approved package insert, is underway, and we are targeting transfer to the wholesaler in the third week of January. We expect delivery of initial orders to transplant centers almost immediately thereafter. Our distribution model is designed to support next-day delivery. Pricing has been carefully considered, reflecting YARTEMLEA 's position as the first and only approved therapy for TA-TMA, its strong efficacy and reassuring safety, and the known risks associated with off-label agents, all of this informed by input from healthcare providers, pharmacists, third-party payers, and P&T committee decision-makers.
We have determined an appropriate initial per vial price for YARTEMLEA to be approximately $36,000. Each vial represents a single dose. Across the pivotal clinical trial and the expanded access program, median utilization was 8 to 10 vials per treatment course. We expect the majority of a TA-TMA patient's course to be administered in hospital outpatient departments where the drug is typically purchased and billed by the hospital. Our reimbursement efforts and coding strategy initiated pre-launch are progressing well. We've established a national ICD-10 diagnostic code for TA-TMA and two associated product-specific CPT procedure codes for YARTEMLEA . Together, these support consistent coding and reimbursement for YARTEMLEA and create a meaningful barrier to the routine reimbursement and use of off-label therapies in TA-TMA. We've already applied for and expect to receive a HCPCS Level II J code for YARTEMLEA to support clear identification and more standardized, predictable reimbursement across all payers.
To assist with the cost of YARTEMLEA in the inpatient setting for Medicare patients, Omeros has applied for a new technology add-on payment, or NTAP. NTAP is a government reimbursement program that provides additional payments to hospitals for certain high-cost innovative medical technologies, really helping to bridge the gap until standard payment systems, or DRGs, incorporate these new therapies. We expect NTAP to become effective in October of this year and to remain active over the subsequent three years. Telephone support is already live. Providers and practice staff can access personalized assistance by calling 1-844-YARTEM1. Our YARTEMLEA Assist program, which helps our customers identify coverage and financial assistance options, will be fully operational in early February. Turning briefly to our balance sheet, as of December 31, 2025, we had approximately $172 million of cash and short-term investments available for operations.
Beyond the U.S., our marketing authorization application is pending with the European Medicines Agency. A decision is expected mid-year. For commercialization of YARTEMLEA outside the U.S., we are evaluating potential partnerships, both global and regional. We view the ex-U.S. opportunity as substantial. Taken together, the U.S. launch of YARTEMLEA and our ex-U.S. strategy extend the commercial opportunity for TA-TMA and further strengthen the MASP-2 platform. With FDA approval having validated the science of MASP-2 inhibition and YARTEMLEA now a commercial product, we plan to expand its indications. The underlying biology, endothelial injury and cellular damage writ large, spans multiple therapeutic areas, and as we build the business, we intend to advance both our long-acting MASP-2 inhibitor, OMS 1029, which is phase II ready, and our MASP-2 small molecule program.
We expect to have more to say about these assets as well as the rest of our pipeline programs in the coming months. With that, Operator, please open the line to questions.
Thank you. As a reminder to ask a question, you will need to press star 11 on your telephone. To remove yourself from the queue, you may press star 11 again. Please stand by while we compile the Q&A roster. Our first question comes from the line of Brandon Folkes of H.C. Wainwright . Please go ahead, Brandon.
Hi. Thanks for taking my questions, and congratulations, Greg, and your team on the approval. Maybe, Greg, if we just look at the pricing that's been set and we look at the label, can you talk about when you expect providers to intervene with these patients?
Now that we have something approved that's on label, pricing seems reasonable to perhaps intervene earlier than you may have with other off-label expensive treatments. Just any elaboration there in terms of when you now expect intervention would be helpful. Thank you.
Sure. Thanks, Brandon. Let me turn that over to our three experts. I'll start with Dr. Duarte.
Thank you very much, Greg. I'm Rafael Duarte. I'm speaking from Madrid. I'm the president of the upcoming European Bone Marrow Transplant Congress. I've been at the board of the EBMT, the European Society, for a decade. I've participated in the studies. I've treated patients with YARTEMLEA . It is true, and I think the question is key because it is true that in the development of the drug, and these are all the drugs, we've been primarily focused on very severe cases and high-risk cases.
As Greg said in his introduction, all cases treated with YARTEMLEA thus far have been high-risk patients. Nevertheless, the reason that the outcomes of these patients are overall poor, even though much better with the new drug, is that we tend to intervene late in the absence of normally effective but safe drugs. I'm sure that as we become familiar with the drug and the drug is available, and thankfully with the broad approval in all TA-TMA cases, we're going to learn to use this drug earlier on. We're going to learn that we don't need to change all the parts of these patients' treatments. We've been sacrificing calcineurin inhibitor therapies just to prevent worsening of this disease, and we're going to be able to manage these patients much more efficiently and also earlier in the process, and that way improve overall outcomes for this condition. Thank you.
Thank you, Rafa, Dr. Duarte. Dr. Rambaldi, Dr. Perales, any thoughts on that as well?
Hi. This is Miguel Perales. I'm the chief of the Adult BMT program at Memorial Sloan Kettering Cancer Center, and I do need to disclose that I have financial interests related to Omeros. I think, as you've heard, the drug is FDA-approved for patients with TA-TMA, and I do think that it's going to be a paradigm shift in the sense that I've actually treated some patients already on the expanded access study, and we have intervened early in the disease course. We have not waited for them to get really sick because we know that those patients are harder to recover.
I think where the big difference has been that historically you would withdraw the immunosuppressive drugs, typically tacrolimus cyclosporine, which were among the main offenders, and patients typically would develop acute GVHD despite whatever you did. Many patients died either of GVHD or of TA-TMA or of complications related to eculizumab, particularly infectious complications. What we've done in the patients that I personally treat on the expanded access study is actually maintain the immunosuppressive drug, and we were sort of able to treat through that, and therefore we had much better outcomes. I've had a couple of patients who were treated successfully and now off drug and are doing well and just in long-term follow-up with me in my practice.
So I think it's a paradigm shift because in the old approach, you would stop the calcineurin inhibitor and then intervene later in the disease course, and now we're moving this up already. But even on the expanded access study, we've already treated patients earlier.
Thank you, Dr. Perales. Dr. Rambaldi, anything that you'd like to add?
Yes. This is Alessandro Rambaldi. I'm working at the University of Milan and the Papa Giovanni XXIII Hospital in Bergamo, and I think that the question was very well taken. And I'd like to emphasize the point that both in the pivotal trial and in the large experience that we have done in the subsequent expanded access program, the patients had to wait for a while because in the pivotal trial, you have to fulfill rigorously all the inclusion and exclusion criteria.
And in the subsequent generous expanded access, it was not immediate by definition to have the access to the drug. So I think that when the drug is made available in the real life in the clinical practice, patients will have access to this innovative treatment much earlier. And I guess that this will be of very much importance for the clinical outcome of our patients with this frequently lethal transplant complication.
Any thoughts on what Dr. Perales mentioned as well about treating directly through?
Yeah. Absolutely, Greg, if I may. I think that overall the paradigm shift is true and it's going to happen, and we've seen that also in other complications. And we start treating more severe cases, but then we move on to earlier cases. Some of the times, as Miguel Perales was saying, these patients already have with all the complications.
It's not only that by discontinuing cyclosporine, tacrolimus, we're going to generate GVHD. Sometimes these patients suffer TA-TMA in the context of GVHD. And we've all treated, I've treated within the expanded access program patients, even patients already with severe organ damage forms of TA-TMA in whom we could not discontinue that. And we've treated through the GVHD and through the calcineurin inhibitors therapy being continued, and we've managed to rescue these patients. So the whole paradigm is changing, and it's going to change for those very severe cases, but it's also going to change for earlier intervention in other patients.
All right. Thank you. Thank you all. Operator, I think next question.
Thank you. Stand by for our next question. Our next question comes from the line of Olivia Brayer of Cantor . Please go ahead, Olivia.
Hey, good afternoon. Thank you for the question.
Greg, my congrats as well on the approval. Can you walk us through how YARTEMLEA fits into hospital DRG economics today and really how that changes once the NTAP is in place? Just trying to better understand how sensitive utilization will be to NTAP timing in some of those transplant centers, considering that I think you said it won't be implemented until October. That's the first question. Second question is, did the FDA approval include any post-marketing study requirements?
Sure. Let's take your first question first.
And what I would underscore initially before handing the response off to Nadia as well to address is that we really see YARTEMLEA being very much primarily used now in the outpatient setting for all of the reasons that you just heard our experts articulate, which is earlier treatment should certainly reduce the need for treatment in-house or in the hospital and moving the majority of the dosing to the outpatient setting, which, as you understand, is an appropriate place and also a favorable place from the facility perspective with respect to treatment. But having said that, let me ask Nadia to comment further on your question regarding the NTAP and inpatient use.
Yeah.
We do expect that YARTEMLEA will be initiated inpatient, and coverage decisions are largely determined at the institutional and prescribing physician level with reimbursement managed through existing DRG or the case rate mechanisms, which vary across the institutions. Given YARTEMLEA 's strong value proposition and early physician interest, we expect high demand with inpatient initiation followed by outpatient continuation, where we expect the majority of the dosing to occur, and come October, we would expect that the new technology add-on payment and NTAP will provide an add-on payment to cover additional costs potentially, and that's under review, and we feel very confident about the submission in that process.
So we're also very encouraged, I have to add, that the messages that we're receiving on a daily basis, that many of the institutions, even before we've reached out to them, have started the P&T approval reviews and discussions about adding YARTEMLEA to formularies.
Your second question was tied, Olivia, to do we have any post-marketing commitments? Cathy, would you just walk through what we have there?
Sure. With respect to post-marketing commitments and post-marketing requirements, there is only one post-marketing requirement, and the report for it is due in 2034. It's a registry that includes a total of 50 adult and pediatric TA-TMA patients with one year of follow-up to assess any major safety findings. There's also a post-marketing commitment to collect PK, PD, and safety data on pediatric TA-TMA patients who are treated with narsoplimab. The report for this study is due in 2033.
In addition to those, there are five CMC-related post-marketing commitments, all of which are quite typical for approved products. Two of these have already been completed, in fact, and will be submitted to FDA this month, and the other three are all on track to be completed this year.
Okay. Great. That's helpful. And just quickly, I wanted to ask a follow-up for Nadia or Greg. You mentioned that the majority of dosing will potentially happen in the outpatient setting versus the inpatient setting. Can you characterize that at all for us and just put maybe how many doses or vials you expect to happen inpatient versus outpatient? I'm sure it'll depend on a case-by-case basis, but any kind of guardrails there?
Right. Thank you, Olivia. Well, certainly it will depend on a case-by-case basis.
But we do have an expectation that two to three doses probably inpatient, then moving to the outpatient facility to the HOPDs.
Okay. Great. Very helpful. Thank you.
And Miguel, I'll ask this before we move on. I'll just ask our experts on the call if they have anything to add given that they live this situation.
Yes. I can comment from a U.S. center perspective. I mean, obviously, it's not a cheap drug, but if you think of the complication as a life-threatening complication, and transplant is not a cheap procedure, and the importance of transplant, that it's a curative option for patients with hematologic malignancies that otherwise would be fatal. So in that context, I think if you have a patient who develops TA-TMA post-transplant, you are going to treat them with an FDA-approved drug that's effective.
I can tell you that the most recent patient I treated who happens to live in Eastern Long Island, even on the expanded access study, we were able to ship drug to our regional site out in Commack, for those of you who are familiar with Long Island. And she received most of her treatment there and was followed in part through a nurse practitioner who practices there and with me via telemedicine. So I think we will see patients quickly transition to the outpatient. And I could even imagine that some patients may be treated outpatient if they're not requiring a heavy transfusion load.
Thank you.
If I can add something, I think that the safety profile of this treatment, of this drug, will greatly facilitate the outpatient use of this treatment. And this is very much important in the setting of the early transplanted patients.
So I don't see any major obstacle for delivering this drug in an outpatient setting.
Thank you, Dr. Rambaldi. No, all of those are great answers.
Also, Greg, perhaps another I mean, Miguel's perspective from a big U.S. center where distances for patients are perhaps longer than they are for Alessandro or me here in Italy or in Spain. But another difference with other transplant complications is that very early transplant complications occur at a time where patients are still very dependent on the transplant center, very close by. So most things are done as inpatients. TA-TMA can occur early, but can also occur later in the disease. And at those points, lots of these patients are already being managed at home.
So I think that that versatility of the treatment and availability of treatment, and I agree with you, perhaps a couple of doses, three doses as inpatients where you're still working with complication, but then the treatment is very feasible to be carried on in ambulatory care as outpatients.
Very good. Very good. Thank you all. Olivia, does that give you the color, I think, that you were looking for, or do you have anything else on that that you'd like to follow up?
No, that was great. Thank you, everyone. Appreciate the comments.
Thank you. Next question.
Thank you. Our next question comes from the line of Steve Brozak of WBB Securities. Please go ahead, Steve.
Hi. Obviously, congratulations on the approval of YARTEMLEA and the launch. This is a little bit of a different question.
How do you view YARTEMLEA in terms of the C5 inhibitor comparison on, let's say, an off-label use? What are your thoughts there? And I'll hop back in the queue. Thank you.
Thanks, Steve. You broke up here just a little bit. Would you mind just maybe repeating that?
Sure. Can you hear me?
We can now. Yes. Go ahead.
Okay. How do you view YARTEMLEA in the C5 inhibitor comparison and on an off-label type of use, or what would your views be there going forward?
Yeah. Great. Look, we think that the off-label use of C5 inhibitors, as we said, really don't stack up to what we've been able to show. I think a great way to address this would be first to, I think, have Dr. Perales.
I know that he's looked specifically at C5 inhibitor use, and it might be, I think, helpful to hear from him. Dr. Perales?
Yes. Thank you, Greg. So I think that's an obvious question to ask because before the approval or even access to narsoplimab, many of us use off-label eculizumab. I had personally experienced patients who had a response to eculizumab but then died of infectious complications. And so we recently reported in the journal BMT in late 2025 our experience with eculizumab in patients with TA-TMA. And what the results show are quite sobering is that there is a very high risk of mortality in these patients, and it's driven by non-relapse mortality. So there is an increase with relapse of the underlying disease, but they're essentially dying of transplant complications. And in most patients, it's actually infections.
I mean, I remember vividly a patient who was doing fine with outpatient, got admitted with sepsis, and died within 48 hours. There was nothing we could do to save that patient. The other relevant publication is a pediatric study that was published recently by Michelle Schoettler, from memory, who's an expert in TA-TMA, particularly in kids. What she looked at was a comparison of patients with TA-TMA who received eculizumab with sort of a matched control group of pediatric patients. It showed also increased risk of life-threatening infections and increased risk of mortality due to infection. I think the major issue with eculizumab and drugs that target that pathway is that you knock out sort of a key aspect of our defenses against infections. Quite frankly, at MSK, at least, we stopped using eculizumab a while ago because of that.
So we just haven't been using it. And then once narsoplimab became available, there was really no reason to use it.
Thank you. Any comments or additions from our other experts?
Well, I would just echo what Miguel said. I think an important part of it is that we've all had long experience. We are one of the largest departments in the country in Spain in use of C5 inhibitors in PNH, in other complications. But the level of profound immunosuppression, cellular and humoral, that these patients have, that TA-TMA allogeneic stem cell transplant recipients have, it's a completely different scenario. It's not the same clinical scenario of using C5 inhibitors in other complications. We've also moved away from C5 inhibition in our adult patients.
We are an adult transplant center, and I think that the safety profile of narsoplimab, apart from the efficacy, but safety profile is most welcome to our patients and to our practice.
Thank you, Dr. Duarte. Dr. Rambaldi, anything additional?
The only thing I would like to add that I'm glad that in Italy, it's very difficult to use off-label drugs in any situation. But here in particular, I'm glad that there is a very high caution in allowing the use of off-label drugs that may interfere so profoundly in the immunological balance of heavily immunocompromised patients like the transplant patients. And I think that we have now, as Miguel recalled us, good evidence to say that eculizumab may be indeed a very dangerous treatment for these patients.
Thank you.
And I think to add from a slightly different perspective is that there's now an ICD-10 code specifically for TA-TMA, stem cell transplant-associated thrombotic microangiopathy, as the only approved drug for TA-TMA. That really only applies to YARTEMLEA . And then there are also, as I think I mentioned or I know I mentioned in the opening comments, that there are two specific procedural codes, so CPT codes, for the administration of YARTEMLEA , one through peripheral vein, one through central vein. And those, again, are very specific to YARTEMLEA . So all of this, I think, in yours, first of all, to the benefit of patients, but also certainly to the benefit of YARTEMLEA . Andreas, anything that you'd like to add there?
Well, I can only echo your thoughts.
I think this is a unique opportunity to use a drug that is approved in this condition, that's well studied in this condition, that has excellent data in this condition for patients that need it. And if you picture these patients, how they get into this situation, these are patients that often have survived the hematologic malignancy. They've gone through the grueling transplant procedures. They've come through all of that, and now they're developing a complication that, with high likelihood, may kill them. And you really don't want that to happen. You want to treat these patients, and you want to improve their outcomes and hope that they can get the benefit of all the grueling procedures that they have gone through. That's always what keeps me going in this field when I think what we're doing for these patients.
And thank you, Andreas.
I think, obviously, when we were considering the commercial aspects of YARTEMLEA , into that calculus, to some extent, came the off-label use of C5 inhibitors. Nadia, do you want to comment on that at all?
Absolutely. Yeah. As we looked at this, we looked at it from two angles, right? Nothing else is approved. What is the value proposition? Then the realistic analog that physicians without other options would compare us to. Beyond drug acquisition cost, off-label eculizumab dosing, which in TA-TMA is often extrapolated from higher-end aHUS dosing, with standardized guidance lacking, particularly in severe adult patients, it drives substantial total costs of care through REMS certification requirements, intensive monitoring, mandatory vaccination, antibiotic prophylaxis, infection management that we've talked about, and treatment failure. Taken together, these cumulative economic burdens materially exceed the carefully calibrated price and value proposition that we have with YARTEMLEA .
The biggest value driver, really, that came back consistently from all the insights is the proven survival benefit, as published in Matsui in 2025 and in Schoettler 2025 as well. Even when other off-label treatments failed and/or were stopped, we still had a survival benefit in salvage therapy. So not that we would position ourselves as second line, but as you heard in the comments earlier, with a broad label like we have, and the safety profile, the benefit-risk profile lends itself to broad use early and even in salvage therapy when there are no other options.
Thank you, Nadia. Steve, I think you had a lot of information delivered to you from, I think, a pretty straightforward question. But do you have any follow-up on that?
No. I very much appreciate the directness and the breadth of the answer. Thank you.
Thank you.
I would now like to turn the conference back to Dr. Demopulos for closing remarks. Sir?
Thank you very much, Operator, and thank you all. In closing, the approval and launch of YARTEMLEA really mark a fundamental shift in how TA-TMA can be treated. For the first time, transplant teams have an FDA-approved therapy specifically indicated for this disease, and that is supported by the compelling clinical data, differentiated safety profile, and a clear pathway for access and reimbursement. We want to thank the patients, the caregivers, the investigators, the number on the call, the experts on the call as well who fit into that, and their clinical teams who made this approval possible. Our objective is pretty clear. It's to make YARTEMLEA the standard of care in TA-TMA, so our job now is execution.
Start with early adopters, expand quickly across the transplant center network, support timely diagnosis and treatment, and let clinical experience, some of which you heard today, guide the adoption. In parallel, we're working to extend YARTEMLEA 's reach through ex-US commercialization and additional indications while continuing to invest in the MASP-2 platform as a whole. Our priorities for the launch are clear: ensuring reliable supply, appropriate access and thoughtful engagement with the transplant community while remaining grounded in what matters most, which is saving the lives of patients facing a life-threatening disease with previously inadequate treatment options. I think we may have another question. Is that right? Operator, do we have another question?
We do, sir. Are you ready for it? One moment. [audio distortion]
Stand by for our next question. Our next question comes from the line of Serge Belanger of Needham. Please go ahead, Serge.
Great. Good afternoon.
Thanks for squeezing me in. Appreciate it. So, Greg, just, I guess, a couple of questions to help us frame and investors frame the TA-TMA opportunity here. First, on prevalence. When we look in the literature, the theme of underdiagnosis is prevalent. But also, the prevalence ranges anywhere from high single digits to as high as that 60% that was referenced previously. So just curious, where does the real prevalence rate for TA-TMA stand? And within those prevalent patients, how many will require treatment with YARTEMLEA ? And then the second question, just regarding duration of treatment. I think in your prepared comments, you mentioned that in the clinical trial that supported approval, the median treatment or the dosage was eight to 10 different doses. In the real world, what should we expect in terms of the number of treatments that these patients will undergo with YARTEMLEA ? Thanks.
Yeah. Sure.
First, let's take the second question first. The number of doses really are derived from a real-world experience because those are representative of our expanded access program. So the median there was the eight to 10 doses that I think I stated in the opening remarks, and I think which you just referenced. So I think, again, there's going to be variability. There always is variability in dosing, any disorder, as you know. But based on the real-world experience that came out of our expanded access program, and interestingly, those numbers were very tightly supported by our pivotal trial, those numbers were eight to 10 doses per therapy course. With respect to the incidence of TA-TMA, which I think was your first question, and you noted that the literature is replete with reference to underdiagnosis, and we fully subscribe to that view.
This has been a disease that has, to date, been, frankly, somewhat amorphous in its diagnosis and its identification, and I think with the work done by the International Harmonization Committee, there has started to be a substantial amount of really kind of palpable and recognizable diagnostic criteria there, so they've turned this amorphous thing into something, I think, more structured. I think there's still. I'll look to the experts, but I think that our view is there's certainly still more work to do there. There's more education. There's greater identification. So yeah, we believe that this is still underdiagnosed. With respect to your number that you asked, we believe the number that I cited in the opening remarks, which comes from the MIDAS study. It's very recent, it's well-respected, at 56% of TMA incidence in stem cell transplant procedures.
We think that that is probably now the best representation of that incidence. But let me stop there and, again, see if our external experts have anything to add or, frankly, any other comments they'd like to make before we continue with the wrap-up. Miguel, Alessandro, Rafa, any thoughts?
I just can. This is Alessandro speaking. I mean, an important point beyond the data that we can talk about is that the incidence and severity of TA-TMA increase for the more fragile patients. And I would like to spend a few words for the pediatric patients in which the allogeneic transplant is offered as the last treatment option in very different clinical conditions. So the patient may be transplanted where the clinical condition is very poor. So the incidence of TA-TMA in those patients receiving frequently a very mild ablative conditioning regimen may be higher than in other situations.
But those are exactly the patients who need an effective treatment the most. So I think it's very important now to have this treatment option for the most fragile patients.
Thank you. Thank you, Dr. Rambaldi. Dr. Duarte, Dr. Perales?
I mean, Greg, I mean, that's a critical question. It's a very important question. I think that you did a very nice summary of what's being changing criteria and changing ways of addressing this amorphous complication, as you put it. I think that the international consensus is, with the evidence there is, but it's the best we've got thus far. And I think that we have to also move from just diagnosing the very severe cases in which disease is at the end of the development of it to also being able to diagnose earlier these patients. So I agree with you, Greg.
I think that that's the best we've got right now, and I think that if anything, we'll be more aware and more able to diagnose the disease earlier in these patients, more so now that we have an effective and safe treatment to offer them.
Thank you, Rafa. Dr. Perales?
No, I just wanted to, yeah, it's hard to add much to what my colleagues and what you already highlighted. I agree fully that it's currently a disease that's very much underdiagnosed. I think the Harmonization Working Group has really done major work there to help us diagnose this condition, and I think the fact that we now have an FDA-approved drug that is both effective and safe, which is a critical aspect, will actually lead to more patients being diagnosed because we'll be more likely to use screening tools to actually look for TA-TMA.
And that's already been implemented at centers across the U.S.
Okay. Very good. Thank you. Serge, did that answer your question, or do you have anything else that would be helpful?
No, that was great. And thanks again for squeezing me in at the buzzer here.
Your timing was impeccable. No problem. But no, this is great. Operator, are there any more questions?
I show no further questions in queue, sir.
Okay. All right. So great. I think the distillate, I think, of what you've heard is that our clear objective, our intention here is to make YARTEMLEA what we believe it will be, the standard of care in TA-TMA. And to repeat a bit of what I had said earlier, really where our job falls now is execution.
I mean, we received from FDA in our collaboration with FDA appropriately a label that is really what we were looking for in breadth with the absence of the safety concerns or the safety components that are often seen with other drugs. All of this translates to really it's on us now to execute, to make sure that we can deliver the drug, make it accessible to the patients who need it. And the purpose of that, of course, is to save the lives of those patients. I think that, frankly, it's been a while we have had an expanded access program, but we clearly have not been able to reach all of the patients or even a large proportion of the patients who needed it. And now we can. So I think that all of that translates to execution for us.
I think we're very well-ready and very eager to do that. I think that if we look beyond MASP-2, we'll continue to advance the broader Omeros pipeline, really with the same discipline that we have approached the MASP-2 program and the MASP-3 program. We're going to be allocating resources to programs where we see the potential for both meaningful clinical impact and significant value creation. Done well, the execution of this strategy, so launching YARTEMLEA , extending its reach beyond the U.S. and into additional indications, and really advancing the broader pipeline. We believe that that will serve both patients and clinicians and create the foundation for durable long-term value for Omeros and its shareholders. With that, let me sign off. Thank you all for your participation, for your attention today.
Again, I want to thank very much our three experts who have joined from around the world at times now that are late in their evenings for two of them and dinner time for another. Thank you very much. We'll continue to keep you all updated.
This concludes today's conference call. Thank you for participating. You may now disconnect.