Good afternoon, and welcome to the Travere Therapeutics business update conference call. Today's call is being recorded. At this time, I would like to turn the conference call over to Nivi Nehra, Vice President, Corporate Communications and Investor Relations. Please go ahead, Nivi.
Thank you, operator. Good evening and thank you all for joining us today on such short notice. Earlier today, we announced the FDA has approved FILSPARI in FSGS. A copy of the press release, along with the slides that we'll be referencing on today's call can be found on our corporate website. Today's call will be led by our President and Chief Executive Officer, Dr. Eric Dube. Eric will be joined in the prepared remarks by Dr. Jula Inrig, our Chief Medical Officer, and Peter Heerma, our Chief Commercial Officer.
Dr. William Rote, our Chief Research Officer, and Chris Cline, our Chief Financial Officer, will join us for the Q&A. Before we begin, I'd like to remind everyone that statements made during this call regarding matters that are not historical facts are forward-looking statements within the safe harbor provisions of the Private Securities Litigation Reform Act of 1995.
Forward-looking statements are not guarantees of performance. They involve known and unknown risks, uncertainties, and assumptions that may cause actual results, performance, and achievements to differ materially from those expressed or implied by the statement. Please see the forward-looking statement disclaimer on the company's press release issued earlier today, as well as the Risk Factors section in our Forms 10-Q and 10-K filed with the SEC.
In addition, any forward-looking statements represent our views only as of the date such statements are made, April 13, 2026, and Travere specifically disclaims any obligation to update such statements to reflect future information, events, or circumstances. With that, let me now turn the call over to Eric. Eric?
Thank you, Nivi. Good evening and thank you all for joining us. Earlier today, we announced that the FDA has approved FILSPARI to reduce proteinuria in adults and pediatric patients aged eight years and older with focal segmental glomerulosclerosis or FSGS without nephrotic syndrome. With this approval, FILSPARI becomes the first and only FDA-approved medicine for FSGS, a milestone that fundamentally changes what it means to be diagnosed with this condition.
For patients and families, this is more than a regulatory event. It is the beginning of a new path forward, where for the first time, there is a medicine specifically approved to reduce their proteinuria, which is central to slowing disease progression. We now have the ability to redefine the treatment landscape.
Importantly, the approved population spans across types of FSGS and aligns closely with how the condition is managed in clinical practice, where patients are routinely assessed and treated based on whether they have current nephrotic syndrome. This approval is based on data from our phase III f study and reflects alignment with the FDA on a well-defined population where the evidence demonstrates meaningful clinical benefit, including proteinuria, eGFR, and kidney outcomes.
From a commercial perspective, FSGS marks an additional indication for FILSPARI, and we are ready to launch. Together with IgA nephropathy, we believe the addressable patient population for FILSPARI now exceeds 100,000 patients in the US. We will be leveraging our experienced rare nephrology teams, established physician relationships, and proven success in launching FILSPARI as a foundational care in IgA nephropathy to drive a successful launch in FSGS.
This is an extraordinary day for the FSGS community and a defining moment for Travere. It represents both the culmination of years of perseverance and the beginning of a new chapter. Today's approval further strengthens our strategy to accelerate growth and our leadership position in rare kidney disease.
Before I turn the call over to Jula, I want to extend my sincere gratitude to the patients and caregivers who participated in our studies, shared their stories, and advocated for new treatment options, the physicians and advocates who've worked alongside us for many years and who, along with regulators, were instrumental in changing the way FSGS is studied today. I would also like to thank the entire Travere team, whose dedication and perseverance over the last 10+ years made today possible. With that, I'll turn it over to Jula to walk through the approved indication in more detail. Jula?
Thank you, Eric. As a nephrologist who treated patients with FSGS for decades, today's approval represents an incredible advancement for the field and, most importantly, for patients who until today had no approved medicine. FSGS is a rare progressive condition that frequently leads to kidney failure. For many patients, the journey begins with abnormal lab findings, mainly elevated protein in the urine called proteinuria, or non-specific symptoms such as fatigue and, in some cases, swelling, eventually leading to a kidney biopsy confirming FSGS.
From there, treatment can be complex and iterative, with physicians trying different off-label therapies over time, typically starting with steroids and then moving to other immunosuppressive therapies. In the absence of a clearly effective medicine, this often becomes a process of trial and adjustment rather than a defined treatment path.
Proteinuria is a hallmark of podocyte injury, is a key driver of disease progression, and is strongly associated with long-term kidney outcomes, making it a critical treatment target. Persistent proteinuria leads to irreversible kidney damage, which over time requires treatment with dialysis or kidney transplant. Even after transplantation, FSGS recurrence remains a real and frightening possibility for many patients and their families with up to 55% recurrence rates post-transplant. In some cases, the disease returns almost immediately.
As Eric highlighted, FILSPARI is now the first medicine ever approved for FSGS and is indicated to reduce proteinuria in adults and pediatric patients eight years and older without nephrotic syndrome. Importantly, the approved indication for FILSPARI reflects a patient population defined by clinical characteristics. Now, many of you will recall that the approval we were originally seeking did not draw this distinction with nephrotic syndrome.
Early last month, we met with the FDA to discuss the ongoing review, and for the first time, they highlighted this path for patients without nephrotic syndrome based on the strength of the data on proteinuria, eGFR, and kidney failure in this patient population. Nephrotic syndrome is a clinical diagnosis which commonly refers to meeting all three of the following criteria, high levels of proteinuria greater than 3.5 grams per day, low serum albumin of less than three grams per deciliter, and the presence of edema.
Notably, this is distinct from nephrotic range proteinuria on its own. For example, a patient with four grams of proteinuria but without low serum albumin would be eligible for FILSPARI.
Also, a patient who has four grams of proteinuria, edema, and low serum albumin could become eligible after they experience a change in any one of these criteria after treatment with alternative approaches. In clinical practice, when a patient presents with active nephrotic syndrome, they're typically evaluated promptly, including with a kidney biopsy, and started on immunosuppressive therapy such as steroids.
This approach is based on the KDIGO clinical practice guidelines, which recommend assessing patients based on nephrotic syndrome status and using immunosuppression for those with nephrotic syndrome versus optimizing foundational care among those without nephrotic syndrome. Importantly, FSGS is a relapsing and remitting condition, and once a patient with nephrotic syndrome has been stabilized with steroids or other immunosuppression, they may become eligible for long-term treatment with FILSPARI.
Patients without nephrotic syndrome represent a population whose disease progression is initiated by podocyte injury and also driven by maladaptive glomerular hemodynamics and pro-inflammatory and pro-fibrotic pathways. All of these mechanisms are directly targeted by FILSPARI's dual endothelin and angiotensin receptor blockade. This is supported by the DUPLEX study, which enrolled a broad population of patients where those without nephrotic syndrome demonstrated even more pronounced treatment effects compared to irbesartan across proteinuria, kidney function, and kidney outcomes.
The data in patients without nephrotic syndrome included robust, durable, and nominally statistically significant reductions in proteinuria, with a 48% reduction for FILSPARI-treated patients, compared to 27% with irbesartan at week 108. This subgroup also had a favorable treatment difference of 1.1 mLs per minute in mean eGFR from baseline to week 108 compared to maximum dose irbesartan.
As noted in our corporate deck, treatment effects on eGFR total and chronic slope both also meaningfully favored FILSPARI over irbesartan, and each were nominally statistically significant. Progression to kidney failure over the two-year measurement period occurred in less than 2% of patients without nephrotic syndrome treated with FILSPARI, compared to 8% with irbesartan, which was also nominally significant. FILSPARI was generally well-tolerated, with a safety profile comparable to irbesartan and consistent across clinical programs, as well as across clinical subgroups, as noted in our label.
FILSPARI will be available through the same REMS program that physicians are familiar with for IgA nephropathy. From a medical affairs perspective, we look forward to continuing to educate and engage with the nephrology community through peer-to-peer forums and field medical education or engagement to support informed clinical decision making as physicians integrate FILSPARI into their FSGS treatment plans.
This approval represents an incredible advancement for the FSGS community who have waited far too long, and we are profoundly grateful to them, their families, and the many physicians whose dedication and perseverance made this moment possible. This approval exemplifies a clear commitment to do better for people living with rare disease such as FSGS. I also want to thank our internal teams at Travere who have worked tirelessly and with urgency to accomplish this outcome for the FSGS community. I'd now like to pass the baton over to Peter for a commercial update. Peter?
Thank you, Jula. We are incredibly excited about today's approval and the opportunity it creates to bring FILSPARI to the FSGS community. From a commercial perspective, this is a highly actionable opportunity, grounded in a patient population that is both clearly defined and actively managed in clinical practice. Nephrologists understand the grave prognosis for most patients with FSGS and are actively seeking to reduce proteinuria in an effort to slow disease progression and preserve kidney function.
Our market research reinforces both the urgency and the opportunity. More than half of the nephrologists believe their patients with FSGS will progress to kidney failure within the next 10 years, underscoring the severity of this disease and the need for earlier intervention.
Additionally, more than 80% of the nephrologists view FSGS as an exceptionally high unmet need and one of the most challenging diseases to manage, with less than 10% of patients today considered optimally managed. There is a clear need for an effective non-immunosuppressive medicine that can provide long-term proteinuria reduction.
The vast majority of surveyed nephrologists indicate that novel non-immunosuppressive therapies are highly desirable in FSGS, and recent market research has further shown FILSPARI to be the most familiar and desired product candidate amongst physicians who treat this rare disease. Based on our current estimates for the approved indication, we believe there are currently more than 30,000 biopsy and genetically confirmed patients with FSGS who do not have nephrotic syndrome under the regular care of a nephrologist in the US.
We expect this number of addressable patients for FILSPARI to grow over time as diagnosis continues to improve and awareness increases. We are building upon strength with FSGS, as FILSPARI is currently the number one most prescribed medicine approved for IgA nephropathy in the US. There is a large overlap in the prescriber base for IgA nephropathy and FSGS, so most of the nephrologists are already familiar with FILSPARI, and many already have experience in their IgA nephropathy patients.
We also see a meaningful opportunity to expand our prescriber base, including pediatric nephrologists, as we extend our reach across the FSGS treatment landscape. Regarding access, also here we have established a robust foundation. FILSPARI is already included in many formularies and payer plans for IgA nephropathy, and we have been educating payers on the high unmet need of FSGS and the lack of approved medicine.
We will now educate payers on the value story of FILSPARI for patients with FSGS without nephrotic syndrome. In the coming months, we expect a supportive access environment to build. As with any new indication, we recognize that a level of education will be required to support broad adoption. In the early stages of the launch, our commercial and medical teams will be focused on educating physicians, payers, and patients on the approved population, the clinical data, and how FILSPARI fits into the treatment decision-making process.
While education will be necessary to build momentum, we are not starting from scratch. We have already established a commercial team of over 100 field professionals who've spent years building relationships in the nephrology community. That team has delivered real results that have helped drive FILSPARI to become the most commonly prescribed therapy that is approved in IgA nephropathy to date.
Now we're able to take that same experience, relationships, and executional strengths and apply it towards a successful launch in FSGS. With Travere TotalCare, we also have an established patient services model in place for FILSPARI that can be directly applied and customized to FSGS patients, positioning us to immediately execute effectively and support education on this new indication.
Just as they do now in IgA nephropathy, eligible patients with FSGS and their caregivers will receive personalized support, including REMS coordination, reimbursement assistance, and co-pay support through Travere TotalCare. Overall, we see a clear and meaningful opportunity to drive adoption within the approved population as we work to build momentum through continued education. In addition, we expect there will be cross-indication synergies with IgA nephropathy as physicians gain experience with FILSPARI and FSGS, which we believe will support adoption across both indications.
In closing, we're incredibly excited and ready to launch FILSPARI as the first and only approved medicine for FSGS, and our team is well-prepared and ready to serve this patient community. Launching in FSGS, together with our continuing IgA performance, will position us for meaningful and durable FILSPARI growth. I'll now turn the call back over to Eric for his closing comments. Eric?
Thank you, Peter. Recently, the team at Travere and I had the opportunity to meet Maddie. She was diagnosed with FSGS at just four years old and spent much of her childhood in and out of hospitals, often unable to participate in everyday childhood moments because of her FSGS. She shared with us, and I quote, "I often missed birthday parties, school, and recess when I was forced to sit on the bench alone because I couldn't keep up with the other kids.
I remember being embarrassed at my kindergarten graduation when my legs gave out on me because I'd been standing too long." What stood out to me was not only her resilience, but the role that she and her family played in advocating for progress in this field.
Because of that effort, Maddie was able to participate in DUPLEX at the age of nine years old and ultimately experienced meaningful improvements that allowed her to regain her energy and begin living a more normal, active childhood. In her words, I was finally able to live my life and be free from feeling sick all the time. She's now 15 years old and still thriving. Stories like Maddie's are why we are here today. This approval underscores our commitment to transforming care for patients with rare kidney diseases, and importantly, to improving what patients and families can expect after diagnosis.
Today marks a defining moment as we now turn our attention to ensuring patients can access FILSPARI as early as possible, because we know that time matters in FSGS. It also begins the next chapter of significant growth for our company.
Finally, to the FSGS community, thank you for never giving up hope and for inspiring us throughout this journey. We would not be here today without you, your courage in participating in our studies, your voices in advocacy, and your unwavering belief in progress. You are the reason we do this work. I'll now turn the call over to Nivi for Q&A. Nivi?
Thank you, Eric. Operator, we can now open up the line for Q&A.
Thank you. Ladies and gentlemen, we will now begin the question-and-answer session. To join the question queue, you may press star then one on your touch-tone phone. You will hear a tone acknowledging your request. If you're using a speakerphone, please pick up your handset before pressing any keys. To withdraw your question, please press star then the number two. As a reminder, we ask that you limit yourself to one question, and if you have another question, please rejoin the queue. We will now take the first question from the line of Joseph Schwartz from Leerink Partners. Your line is open.
Great. Thanks so much, and congratulations to the whole Travere team on this great win. I guess I'll ask if you guys have a sense of the percentage of patients who initially present with nephrotic syndrome, who might ultimately receive a confirmed FSGS diagnosis, and might ultimately be label eligible?
Joe, thanks so much for the question. Jula, I will turn that one over to you.
When a patient presents with nephrotic syndrome, they typically get a biopsy very quickly. For nephrotic syndrome, you want to find out if they have FSGS, but there are other causes other than FSGS. It's harder for me to give you an overall prevalence based on nephrotic syndrome or not. I can tell you, if they've got a diagnosis of FSGS, how many patients might have nephrotic syndrome at a single point in time, and that data comes from the DUPLEX trial. In our study, patients who, at the time of enrollment, who had known FSGS, less than 20% of them had active nephrotic syndrome.
Recall, these patients are going to be treated, so they might go in and out of nephrotic syndrome over time. It's not a static condition because this is a relapsing and remitting condition.
Very helpful. Thank you.
Our next question is from Anupam Rama from JP Morgan. Your line is open.
Hi, guys. This is Priyanka on for Anupam. Congratulations on the full approval. Just a question on the sales team that's in place. I understand that there'll be a proportion that will need to focus on pediatric nephrologists. I was just curious, how much larger would you consider growing the broader sales team to help cover that physician population? Thanks.
Priyanka, thanks for the question. Peter, I'll turn that one over to you.
Absolutely, Priyanka. Great question, and our sales team has already been expanded. We did that at the end of last year, so they're in place. Historically, we have spoken about, we are focused on 6,000 nephrologists that cover about 90% of the IgA nephropathy patient population. We're expanding that now also for pediatric nephrologists. We are now focused on about 7,000 nephrologists in the US that includes pediatric nephrologists.
Maybe also important to note, and I've spoken about this in the past, there's a high overlap between those physicians that treat IgA nephropathy and FSGS. We build upon a base that is already familiar with FILSPARI.
Our next question is from Vamil Divan from Guggenheim Partners. Your line is open.
Great. Thanks for taking my question. Let me add my congrats also. I know it's been a long process to get to here. I guess my question is really around sort of the patient population here, because you're.
Before today, you were already saying 30,000 patients that could be candidates for FILSPARI, but I thought that was more based on primary and genetic FSGS. Now, this seems to be a broader approval for secondary, but then you have the exclusion of patients with nephrotic syndrome. Your number is still just saying over 30,000. I would think the population is maybe much larger than 30,000 now. Does that sort of wash out the sort of broader indication within removing nephrotic syndrome?
If you could just sort of walk us through the numbers there a little bit on what the secondary population means, or maybe you don't think it would get much uptake there if there's other options or anything around how this broader indication could impact how you think about it commercially would just be very helpful. Thank you.
Sure. Vamil, thanks so much for the question. Yes, we do see that today there are over 30,000 patients that are diagnosed and under the care of a nephrologist that would be eligible based on this approval. What we have done is we've added those patients that we believe currently have secondary FSGS and removed the proportion that we believe overall would have current nephrotic syndrome.
Now, over time, we do believe that with growing awareness, with the availability of an approved medication, that patients may be diagnosed and biopsied earlier, which would allow for that addressable population to grow over time. We do see this as a very meaningful opportunity, and as we've seen in other rare diseases, we do expect the addressable population to grow.
Okay. Thank you.
Thank you.
The next question is from Laura Chico from Wedbush Securities. Your line is open.
Good afternoon. Thanks very much for taking the question and congratulations. Jula, you mentioned that the nephrotic syndrome discussion with FDA was somewhat new, and I'm wondering if you could expand on that a little bit around the labeling discussions with nephrotic syndrome. What would be necessary to demonstrate, I guess, in a clinical trial setting to expand FILSPARI's label to encompass that? Is that something that you would pursue? Thank you.
Thanks, Laura. Jula?
Yeah. As I mentioned in my prepared remarks, this occurred very recently in our meeting with the FDA last month, and there were a couple of reasons why they honed in on this patient population. First, the magnitude of the treatment effect against an active comparator on proteinuria was greater in this population versus the overall population and versus those who have active nephrotic syndrome. The additional aspect is that there was also meaningful and statistically significant effects on eGFR as well as on kidney failure endpoints.
I do want to highlight that even though we don't have as great of treatment effect on proteinuria in the patients with active nephrotic syndrome, it's not that the therapy doesn't work, it's that in this patient population, the treatment effect against an active comparator wasn't as great, and it's a noisier patient population.
The signal to noise, it's messy in this patient population. You additionally asked about what it would take. We do believe that the vast majority of patients with FSGS, whether they're eligible today or will be eligible in the future, can potentially benefit from FILSPARI. As I mentioned earlier, less than 20% of patients with FSGS have nephrotic syndrome at a single point in time.
It's important to consider that if a patient has four or five grams of proteinuria and low albumin and edema, if you treat them and change one of those characteristics, and remember, these are sick patients, so you're trying to stabilize them. They can get FILSPARI in the future once they get stabilized. We are very pleased and believe that this is a broad approval for patients over time.
The next question is from Tyler Van Buren from TD Cowen. Your line is open.
Hey, guys. Congratulations on the approval, a tremendous outcome for Travere and for patients. Obviously, the addressable population for IgAN is significantly larger than FSGS, but I wanted to get your latest thoughts on what you believe the ultimate penetration of FILSPARI will be in FSGS compared to IgAN over the long term.
Peter, would you like to take that?
Yeah, happy to take that question, Tyler, and you're right. We expect that we will see a more rapid uptake in FSGS relative to what we saw in IgA nephropathy for several reasons. One is we don't have to establish the unmet need. Like every nephrologist you speak with, they are very well convinced that those patients need treatment urgently and that new treatments are necessary. As I mentioned earlier, this is largely the same call point as that we have with already experienced in large amount of physicians. FILSPARI is already established well.
Having said that, we also need to educate the stakeholders, both the nephrologists, the patients, and the payers, and that may take time, but overall, we see a more rapid uptake in this patient population relative to IgA nephropathy.
Yeah. Thanks, Peter. Tyler, let me add that we see both IgA nephropathy and FSGS as very meaningful opportunities for future growth. A patient with IgA nephropathy and FSGS deserve equally FILSPARI. As we look out, we see the potential for peak year sales over $3 billion when we look at the combination of these two indications. Our job right now, as Peter mentioned, is to make sure that we're out there very quickly because patients deserve it, and to be able to educate physicians on this label and the opportunity to do better in FSGS.
The next question is from Prakhar Agarwal from Cantor Fitzgerald. Your line is open.
Hi. Thank you for taking my questions, and congratulations on the approval. Maybe just firstly, you mentioned less than 20% have active nephrotic syndrome. Could you clarify if that's relevant for secondary FSGS as well? What could the uptake be in primary versus secondary FSGS, given secondary population was not included in DUPLEX, but a much larger segment overall. Maybe just a quick follow-up, if you could confirm the pricing here, for the 800 mg dose. Is it double the price of IgAN? Thank you so much and congrats again.
Thanks, Prakhar. I'll take the last part first on pricing. Yes, the per patient, the dosing is higher for adult patients with FSGS. The per pill is the same. A patient with FSGS would have a higher cost to payers. Our goal overall is to make sure that every single patient has access to FILSPARI that is eligible. Jula, I'll turn that first part of the question to you around active nephrotic syndrome and primary versus secondary.
Certainly. The rationale for having patients with active nephrotic syndrome having a different treatment algorithm, and this is in the Kidney Disease: Improving Global Outcomes guideline, is because you're trying to identify patients with clinical characteristics, with laboratory findings, who are more likely to have primary FSGS and be needed to be treated with an immunosuppressive therapy. That's why that characteristic and classification is even there, because patients who do not have primary FSGS typically don't have nephrotic syndrome.
Your question was at the heart of it, how many patients with secondary FSGS or even undetermined cause or genetic have active nephrotic syndrome? It's a low proportion. When we took an all-comers population, primary, genetic, we did try to rule out secondary, but we've got patients with undetermined cause.
We do see that at that single point in time when patients got into DUPLEX, as I mentioned earlier, less than 20% had nephrotic syndrome. It's not a typical presentation for patients with secondary FSGS.
With regard to uptake, I think it's too early for us to comment on that. I think we see that there is a high unmet need and an urgency to really intervene with better therapies like FILSPARI. Our goal is to make sure that we're reaching all of these patients, and I'm not sure that we've heard much in terms of physicians saying that they're not excited across the board. We really are going to be trying to reach every one of these patients.
Our next question is from Mohit Bansal from Wells Fargo. Your line is open.
Hi, this is Sadia Rahman on for Mohit. Congrats on the approval. I'm just wondering on the question of nephrotic syndrome. In clinical practice, when doctors think about nephrotic syndrome, is the focus on that proteinuria level that patients have, or are they also focused on edema and the albumin criteria that you outlined? Thanks.
Thanks, Sadia. Jula, I'll turn that one over to you.
They're focused on all of them. In order for a patient to have a clinical definition of nephrotic syndrome, they need really elevated proteinuria, low serum albumin, so that's also part of it, and edema. It really is the triad of all three of those in order for someone to have active nephrotic syndrome. As I said earlier, the reason you want to classify someone according to that clinical criteria is because you treat them differently.
You're going to give steroids to a patient who has active nephrotic syndrome or other immunosuppression, and you're going to support them with supportive therapies if they don't have that clinical presentation. It is an important characteristic, something that we look for to try and figure out how we should appropriately treat that patient initially.
Got it. Thank you.
The next question is from Gavin Clark-Gartner from Evercore. Your line is open.
Thank you. You have Evie on for Gavin. Congratulations on the approval. Could you provide some color on if you'll be providing FSGS-specific PSFs moving forward or any metrics to break out FSGS versus IgAN contribution, and whether your gross-to-net will now change as you launch FSGS too? The second part of my question is if you could comment on the current discontinuation rates seen in IgAN and how FSGS could compare to that. Thank you.
Okay. Chris, I'll turn the first part over to you, and Peter, you can talk about discontinuation rates.
Perfect. Thanks for the question, Evie. First on the PSFs and the plan reporting for metrics, no change at this point. We'll, of course, continue to evaluate as we move forward, but the plan for now is to provide aggregate PSFs and revenue. On the gross-to-net front, no change there. The expectation remains the same for this year. We're anticipating gross-to-net in the mid-20s for the full year. Peter, I'll turn the one over to you.
Yeah. With regards to the discontinuation, what we have seen is very high compliance and persistence for FILSPARI in IgA nephropathy, and I'm expecting similar rates for FSGS because this is an even higher motivated patient population that has been waiting for the approval of FILSPARI. I'm expecting a high compliance and persistence rate there.
Yeah, Peter, if I can, I'm just going to compliment your team with Travere TotalCare. They do an outstanding job of supporting these patients throughout their journey. I think that that is something that we will continue, as Peter mentioned, for the FSGS patients as well.
Great. Thank you.
Next question is from Maury Raycroft from Jefferies. Your line is open.
Hi, I'll add my congrats on the approval, and thanks for taking my question. As it relates to PSS, do you have perspective into numbers of eligible patients waiting for therapy at launch, and could there be a bolus effect? And also wanted to check on whether there are any new post-marketing requirements from FDA.
All right. Peter, why don't you take the question on eligible patients? Bill, we'll give you your first question on post-marketing.
Excellent. Well, Maury, thanks for that question. Your question was about warehousing. We do not expect a significant bolus of patients, as FSGS patients are seen on a regular basis by their nephrologist. Typically, they see their nephrologist every three months. I would think that is the natural cadence for future uptake, especially if you realize how busy, especially community nephrologists are. Not a significant bolus, but a steady uptake I'm anticipating.
Yeah.
With respect to post-marketing requirements, we had no new requirements added with the approval of FILSPARI for FSGS.
Got it. Okay. Thank you very much.
Mm-hmm.
Thanks, Maury.
Our next question is from Yigal Nochomovitz from Citigroup. Your line is open.
Yeah. Congratulations as well on the approval. I was just curious, given that you mentioned that this topic of nephrotic versus non-nephrotic syndrome came up very recently, last month. I'm curious if you could elaborate now on what was asked at the end of December in 2025 when you got those late data requests from the FDA. Were there clues there that they were looking down this path regarding nephrotic or non-nephrotic, or was that something entirely different?
Bill, I'll hand that over to you.
Yeah, no, it's a good question. This was a recent development, as you've heard on the call. We learned about the agency's preference for this subgroup early in March. As we stated before, the IRs that we received right at the holidays, those were related to the overall clinical meaningfulness of FILSPARI. There they were looking at the overall population in DUPLEX, and it wasn't split based on any subgroups at that point.
Okay. If I could just follow up. The definition of the nephrotic syndrome, is that a single point in time, or does it have to be measured at multiple points to qualify?
Jula?
It's one single point in time. It's typically how you use it to define a patient who does or does not have active nephrotic syndrome. Again, this is a relapsing and remitting condition, so a patient can get treated with an immunosuppressant therapy today, as well as other supportive care if they've got active nephrotic syndrome, with a goal of changing their condition. It certainly can change over time. A patient who may not qualify at one point in time could qualify if there's a change to any one of those parameters.
Maybe their proteinuria goes down or their albumin goes up in their blood or their edema goes away. Treat them with a diuretic and their edema goes away, they would no longer be considered to have active nephrotic syndrome.
Our next question is from Jason Zemansky from Bank of America. Your line is open.
Good afternoon. Congrats on the approval, and thanks so much for taking our question. Peter, maybe to connect the dots on some of your comments regarding commercial dynamics, but what are the key levers you're focused on in terms of driving adoption here? I know you've mentioned education and having the large bolus of patients, but what are the, I guess, primary hurdles in getting a patient on treatment?
Thanks, Jason. Peter?
Yeah, I don't think I said a large bolus of patients. Just to clarify on that one. I think for FSGS, this is highly anticipated. As I mentioned before, we do anticipate a faster uptake relative to our IgA nephropathy launch because FILSPARI is a known entity for many of these nephrologists, with an overlap of over 80%. Still, you need to educate them. They need to be educated that FILSPARI is now approved, what the patient population is.
The same you do that to nephrologists as well as the payers and the patients. This is the regular uptake, educating the prescriber base, the patients and the payers. We're building on strengths. That's what I mentioned earlier. FILSPARI is already included in many of the formularies, the payer plans. We build upon that access approval as well.
I think we're in a very strong position, but we still need to educate the individuals, and that's our core focus in the next few months.
Great. Thanks.
Our next question is from Alex Thompson from Stifel. Your line is open.
Hey, great. Congrats on the approval, and thanks for taking our question. Maybe one on IP, you've talked about in the past working on expanding IP for FILSPARI and potentially extending exclusivity beyond 2033. Could you talk a little about the progress there and if we should expect any developments in the near future? Thank you.
Alex, thanks for the question. Our current planning assumption as you state, is 2033, and we do have several applications, some of them ongoing review. There's no specific updates at this time, but I can say that they are actively being reviewed and we're actively working on them. Certainly, having today's approval, we believe gives us continued support of the LOE, including our expected Orphan Drug Exclusivity.
Great. Thank you.
Thank you.
Ladies and gentlemen, this concludes the question and answer session. I'll hand the call back over to Nivi.
Great. Thank you everyone for joining us this evening. We're very excited about our path forward, and we'll continue to share more updates along the way. Have a great rest of your evening.
Ladies and gentlemen, this concludes the conference call. Thank you for your participation, and have a nice day.