Travere Therapeutics - Earnings Call - Q2 2025
August 6, 2025
Executive Summary
- Q2 2025 delivered record revenue of $114.4M and non-GAAP EPS of $0.13, driven by FILSPARI momentum and a $17.5M CSL Vifor milestone; GAAP EPS was -$0.14.
- FILSPARI U.S. net product sales reached $71.9M (+165% YoY) with 745 new PSFs; U.S. net product sales for total products were $94.8M.
- Post-quarter, FDA approved REMS modifications for FILSPARI (quarterly LFTs; removal of embryo‑fetal monitoring), a tangible access catalyst; FSGS sNDA accepted with PDUFA Jan 13, 2026 and an AdCom planned.
- Consensus was handily beaten on revenue and EPS; EBITDA missed versus consensus (likely mix of milestone and operating leverage), setting up estimate revisions focused on sustained top-line trajectory and margin normalization (see Estimates Context).
What Went Well and What Went Wrong
What Went Well
- FILSPARI commercial execution: “This quarter marked our strongest commercial performance to date, with increased momentum for FILSPARI…” — Eric Dube, CEO.
- Robust demand KPIs: 745 new PSFs (+~43% YoY) reflecting expanding prescriber base and earlier use in treatment journey.
- Ex-U.S. progress and monetization: EU/UK full approvals triggered $17.5M milestone; Renalys Japan Phase 3 topline expected 2H 2025.
What Went Wrong
- SG&A inflation: GAAP SG&A $76.2M (+$11.4M YoY) reflecting higher amortization of royalties and launch prep for FSGS, pressuring operating margins.
- Tiopronin softness and generic risk: Tiopronin net product sales fell YoY to $23.0M in Q2; management anticipates more generic competition near term.
- EBITDA below consensus: EBITDA actual of $1.37M* vs $3.13M* consensus, indicating operating cost intensity and milestone accounting dynamics weighed on near-term profitability*.
Transcript
Speaker 10
Good afternoon and welcome to the Travere Therapeutics second quarter 2025 financial results conference call. Today's call is being recorded. At this time, I would like to turn the conference over to Nivi Nehra, Vice President, Corporate Communications and Investor Relations. Please go ahead, Nivi.
Speaker 8
Thank you, Operator. Good afternoon and welcome to Travere Therapeutics' second quarter 2025 financial results and corporate update call. Thank you all for joining. Today's call will be led by Dr. Eric Dube, our President and Chief Executive Officer. Eric will be joined in the prepared remarks by Dr. Jula Inrig, our Chief Medical Officer, Peter Heerma, our Chief Commercial Officer, and Chris Cline, our Chief Financial Officer. Dr. Bill Rote, our Chief Research 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 factor section in our Form 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, August 6, 2025, 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.
Speaker 3
Thank you, Nivi. Good afternoon and thank you all for joining us. The second quarter of 2025 was a standout for Travere Therapeutics, a reflection of strong strategic execution and continued momentum in delivering against our mission. At the heart of this progress is FILSPARI, where we are advancing our leadership in rare kidney disease by deepening our impact in IgA nephropathy and laying the foundation for potential expansion into focal segmental glomerulosclerosis. In IgA nephropathy, we delivered our strongest commercial quarter to date, with continued demand driven by both new and repeat prescribers. As the IgA nephropathy treatment landscape evolves, physicians are increasingly adopting FILSPARI as foundational care, recognizing the meaningful and consistent outcomes it delivers, and doing so earlier in the disease process. This growing confidence reflects our ongoing strategy to establish FILSPARI as the new foundational therapy for IgA nephropathy.
There are several pillars to this strategy that we expect to be further solidified through year-end. First, the continued generation of robust clinical evidence to support the use of FILSPARI across a broad range of patients and in combination with other classes of medicines. Second, broad access, aligned with the full approval indication statement, payer coverage, and an expected modification of the liver monitoring REMS and removal of the pregnancy testing REMS. Finally, the continued real-world clinical experience and growing recommendation by nephrologists and treatment guidelines that recognize FILSPARI's ability to reduce proteinuria and reinforce the benefits of getting patients to complete remission. I am pleased with the tremendous progress that our team has made to date, which sets us up for sustained growth in an expanding IgA nephropathy market.
Our performance in Q2 reflects the strength of this positioning and the growing use of FILSPARI as a foundational nephroprotective treatment in IgA nephropathy, even as new treatments enter the market. While it's still early days in the evolving IgA nephropathy treatment landscape, FILSPARI's performance is directly aligned with the expectations that we have set over the last few years and validation of its path to foundational use. Jula Inrig and Peter Heerma will review the progress of our strategy in greater detail. We've also seen strong progress outside of the United States by our partners CSL Vifor and Rhenalis as they look to expand access to FILSPARI internationally. We've entered the second half of the year from a position of strength, and we're ready to build on this momentum. The sNDA review process for a potential second indication for FILSPARI in FSGS is advancing as expected.
We're preparing for what could be an extraordinary milestone for Travere Therapeutics and the FSGS community. If approved, FILSPARI would become the first ever treatment approved for this underserved patient community, a breakthrough for patients, and a near and long-term growth opportunity for our company, given that there are no other FSGS therapies likely to be available in the near future. Beyond FILSPARI, we continue to advance our pipeline with a drive to transform paradigms in rare diseases like classical homocystinuria, and we remain on track to reinitiate enrollment in the Harmony Phase 3 study for pegtibatinase next year. With a robust and growing foundation in IgA nephropathy, the potential to be the first approved medicine in FSGS, and a pipeline built for continued innovation, we remain confident in the road ahead. I will now hand the call over to Dr. Jula Inrig for an update on our clinical programs.
Jula.
Speaker 8
Thank you, Eric. As a nephrologist, it's incredibly rewarding to witness the continued innovation in IgA nephropathy, a disease where not long ago patients had very few options. We are expanding the body of evidence that supports the foundational role of FILSPARI across a broad spectrum of IgA nephropathy patients at risk of disease progression, ranging from those who are newly diagnosed to those with recurrent disease post-transplant. FILSPARI's unique ability to target two pathways causing kidney injury, endothelin-1 and angiotensin-2, provides patients with IgA nephropathy a non-immunosuppressive treatment option to help preserve kidney function. We were pleased to engage with the medical and patient community at several recent congresses, where we presented important new data that continue to reinforce the nephroprotective effects, strong safety profile, and emerging disease-modifying potential of FILSPARI.
Select data at these congresses include: in the Phase 2 SPARTAN trial, when used first-line in treatment-naive IgA nephropathy patients, FILSPARI-treated patients achieved an approximately 70% proteinuria reduction, with nearly 60% of the patients in the study reaching complete proteinuria remission and stable eGFR through 24 weeks. Also, in the SPARTAN study, an analysis of patient samples showed that FILSPARI-treated patients with IgA nephropathy demonstrated rapid and sustained reductions in urinary B-cell activating factor, or BAFF, and complement factor C5b through 9, as well as reductions in pro-inflammatory and pro-fibrotic biomarkers. When taken in combination with our preclinical data showing FILSPARI protects from mesangial deposition of IgA, these data suggest a potential role of optimal dual inhibition of endothelin-1 and angiotensin-2 as modifying the underlying disease.
In the Phase 3 PROTECT open-label extension that is ongoing, patients transitioning from maximally titrated irbesartan to FILSPARI after the double-blind period also achieved approximately 50% reductions in proteinuria and a relatively stable eGFR up to one year. Together with the kidney function preservation FILSPARI provides, these new data further reinforce FILSPARI's disease-modifying potential in IgA nephropathy without immunosuppression. As the IgA nephropathy treatment paradigm evolves, we expect combination therapy to become the new standard to help more patients reach complete proteinuria remission, which is recognized as a treatment goal in the draft update to the KDIGO guidelines. FILSPARI remains uniquely positioned as the only medicine to replace RAS inhibitors as a more effective foundational therapy in IgA nephropathy, with a profile that is complementary to the emerging therapeutic classes.
We are also approaching the August 28 PDUFA date for the removal of the embryofetal toxicity REMS and the potential modification of the liver monitoring REMS to quarterly. With no cases of Hy's law to date, we remain confident in the safety profile of FILSPARI to support this change. Turning to FSGS, our sNDA seeking full approval of FILSPARI in FSGS was accepted by the FDA with a PDUFA date of January 13, 2026. As a reminder, the work by the independent Paracel Group established proteinuria as a valid surrogate endpoint for kidney failure in FSGS and helped pave the way for regulatory consideration of proteinuria reduction for full approval. The sNDA review process is advancing as expected, and we're preparing for an advisory committee to discuss FILSPARI as the first potential approved medicine for FSGS.
Our team is actively preparing to present the strong data from DUPLEX and DUET in the context of the independent Paracel findings. For example, earlier this quarter, we presented new analysis from the DUPLEX study that confirmed the Paracel findings. In DUPLEX, significantly more FILSPARI-treated patients achieved either partial or complete remission compared to irbesartan. Importantly, those patients who achieved partial or complete proteinuria remission in the study, irrespective of treatment arm, had a 67% to 77% lower risk of kidney failure, respectively. These data represent the first trial-level evidence in support of the independent Paracel analyses of proteinuria as a validated surrogate endpoint in FSGS. Lastly, on our HCU program, we continue to be excited about the potential of our investigational enzyme replacement therapy pegtibatinase.
We have made strong progress on our manufacturing scale-up to support our Phase 3 trial and a future commercial launch, and are on track towards restarting patient enrollment in the Phase 3 Harmony study next year. I'll now turn the call over to Peter for a commercial update. Peter?
Speaker 1
Thank you, Jula. I'm pleased to report that our commercial team executed exceptionally well in Q2, as demonstrated by our strong performance metrics. FILSPARI net product sales reached approximately $72 million in the U.S. in the second quarter, representing significant year-over-year growth. This performance was driven by strong demand, expansion, and deepening of the prescriber base, as well as further efficiencies in our fulfillment process and follow-up therapy compliance and persistence. As the only fully approved non-immunosuppressive kidney-targeted therapy for IgA nephropathy, FILSPARI remains uniquely positioned to replace the historical standard of care in this evolving treatment landscape. The growing recognition of FILSPARI's nephroprotective profile, not just from returning prescribers but also from nephrologists who are new to the brand, resulted in 745 new patient start forms this quarter, an approximately 43% increase compared to the same period last year.
At a time when new treatment options are emerging for IgA nephropathy, feedback from our field teams and recent market research emphasized physicians' confidence in FILSPARI's established position in clinical practice. Nephrologists regularly cite FILSPARI's consistent, rapid, and sustained proteinuria efficacy with long-term kidney preservation benefits, a safety profile that allows for chronic use, and a patient-friendly once-daily oral administration that optimally inhibits two critical kidney-damaging pathways as key reasons for making FILSPARI their foundational therapeutic option. Importantly, many physicians are choosing FILSPARI earlier in the treatment journey. This reflects a growing emphasis on earlier intervention and a shift away from legacy approaches, such as the off-label use of RAS inhibitors or steroids. Based on our research, about 70% of the addressable patients with IgA nephropathy have elevated proteinuria levels below 1.5 grams per gram.
With the proteinuria threshold being removed in the FILSPARI label at full approval, FILSPARI is particularly well positioned in this large patient segment, allowing for sustainable demand potential. As we look to the remainder of the year, as with any rare disease product, seasonality could drive some variability quarter over quarter, but we expect that we will continue to identify new prescribers and that the use of FILSPARI will further deepen as foundational care amongst current prescribers. We believe this will be driven by continued positive experience consistent with FILSPARI's superior clinical profile relative to historical standard of care, and also driven by the anticipated final PDO guideline publication and the potential REMS modifications, which may further simplify access for patients. Turning to FSGS, if approved, FILSPARI would become the first approved therapy for FSGS, a progressive and often debilitating rare kidney disease with a significant unmet need.
Given the feedback from nephrologists and the broader FSGS community, we believe FSGS could be an even bigger opportunity with a more rapid uptake versus what we have experienced with our launch in IgA nephropathy. We are actively expanding and preparing our commercial organization to be ready to serve this patient community, beginning at potential approval early next year. In summary, Q2 was another quarter of strong execution and meaningful growth for FILSPARI amidst the evolving IgA nephropathy treatment landscape. We remain confident in our strategy and are encouraged by the feedback from the medical community and the continued momentum in U.S. adoption. With a growing body of clinical and real-world evidence, expanding prescriber engagement, and the potential to serve more rare kidney disease patients through future label expansions, FILSPARI is well positioned to continue its leadership as foundational treatment.
Let me now turn the call over to Chris for the financial update. Chris?
Speaker 7
Thank you, Peter, and good afternoon all. Our financial foundation continues to strengthen. In the second quarter, net product sales grew approximately 82% over the same period last year, and we continue to make disciplined investments in areas of high growth, such as in building further momentum for FILSPARI in IgA nephropathy, preparing our organization for a potential launch of FILSPARI in FSGS, and advancing manufacturing to restart enrollment in the pivotal pegtibatinase study. Beginning with revenue, in the second quarter, we generated U.S. net product sales of $94.8 million. As Peter highlighted, FILSPARI continued to grow significantly in the second quarter, generating $71.9 million in U.S. net product sales.
Thiola and Thiola EC contributed $23 million in net product sales for the second quarter, and these medicines continue to be a meaningful option for patients living with cystinuria, but as we've highlighted previously, we anticipate more generic competition in the coming quarters. During the second quarter, we also recognized $19.6 million of license and collaboration revenue, which results in total revenue of $114.4 million. Included in the license and collaboration revenue line this quarter is the previously announced one-time $17.5 million milestone payment from CSL Vifor, which resulted from the conversion of conditional approval of FILSPARI to full approval in Europe earlier this year. Turning to operating expenses, our research and development expenses for the second quarter of 2025 were $49.4 million compared to $54.3 million for the same period in 2024.
The decrease in R&D is largely attributable to reduced clinical activity in the Phase 3 Harmony study while we optimized our manufacturing efforts. On a non-GAAP-adjusted basis, R&D expenses were $45.4 million compared to $50.6 million for the same period in 2024. Selling, general and administrative expenses for the second quarter were $76.2 million compared to $64.8 million for the same period in 2024. The increase in SG&A is largely attributable to increased immunization expense related to FILSPARI royalties, as well as increased investment to support the ongoing launch of FILSPARI in IgA nephropathy following full approval and preparing for a potential FSGS launch in January. On a non-GAAP-adjusted basis, SG&A expenses were $55.5 million for the second quarter compared to $48.3 million for the same period in 2024.
Total other expense, net, for the second quarter of 2025 was immaterial compared to net expense of $1.9 million in the same period in 2024. Net loss for the second quarter of 2025 was $12.8 million, or $0.14 per basic share, compared to $70.4 million, or $0.91 per basic share, for the same period in 2024. On a non-GAAP-adjusted basis, net income for the second quarter of 2025 was $11.9 million, or $0.13 per basic share, compared to a net loss of $50.1 million, or $0.65 per basic share, for the same period in 2024. As of June 30, 2025, we had cash, cash equivalents, and marketable securities totaling approximately $319.5 million.
As I highlighted earlier, this cash balance reflects the net proceeds of the $17.5 million payment we received from CSL Vifor during the quarter, and we remain on track to potentially achieve additional milestone payments tied to key market access achievements later this year and sales-based achievements in the future, which should further enhance our financial flexibility. Looking ahead, we expect continued revenue growth driven by robust underlying demand for FILSPARI in IgA nephropathy, with a strong balance sheet and potential additional incoming milestone payments, as well as a disciplined approach to our investing in our key growth drivers. We are well positioned to execute on our strategy and deliver sustainable value over both the near and the long term. I'll now turn the call back over to Eric for his closing comments. Eric?
Speaker 3
Thank you, Chris. As you've heard, our team has delivered strong performance across our priorities for the first half of 2025. We are well positioned and eager to continue this momentum. My team and I are deeply motivated to support the rare disease communities we serve. Recently, I had the honor of attending the annual Spark Patient Meeting of the IgA Nephropathy Foundation. At the meeting, I heard many stories of resilience and of hope. This community has been advocating and hoping for a future with therapies developed for them that can stave off kidney failure. We are proud to be part of this journey, and we are committed to the same goal for the FSGS and HCU communities. Now, let me turn the call over to Nivi for Q&A. Nivi?
Speaker 10
Thank you, Eric. Operator, we can now open up the line for Q&A.
Speaker 9
Thank you. We will now begin the question and answer session. To ask a question, you may press star, then one on your touch-tone phone. If you're using a speakerphone, please pick up your handset before pressing the keys. To withdraw your question, please press the pound key. 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 Swartz from Lyric Partners. Your line is open.
This is Will on for Joe. Thanks for taking our question and congrats on this strong progress this quarter. One for FSGS, as you prepare for the ADCOM, what do you anticipate the major topics could be, and how do you plan to respond to the FDA's inquiries here? Do you have a sense for who might be on the panel itself? Given this group of experts will likely include nephrologists and cardiologists, how do you plan to effectively message your case to these two different groups of physicians? Thank you.
Speaker 3
Will, thanks so much for the questions. Jula, I will turn those over to you.
Thanks for the question. Good point. Anytime a rare disease goes before an advisory committee, there's certainly an educational component that we need to do about the disease and the pathophysiology. Importantly, there's both nephrologists and cardiologists part of the panel, and they all know that proteinuria is harmful, and they know the importance of blocking both the RAS system and endothelin-1 to reduce cardiovascular and renal outcomes. We certainly are prepared to educate the mix of panelists. I think importantly about the biologic plausibility supporting proteinuria as a validated endpoint, why eGFR is challenging in FSGS, and then followed by the strong clinical data showing FILSPARI meaningfully and significantly reduced proteinuria compared to an active comparator.
Great, thank you so much.
Speaker 0
Thanks, Will.
Speaker 9
All right, next question comes from the line of Anupam Rama from JP Morgan. Your line is open.
Speaker 0
Hey guys, thanks for taking the question. Just wondering if you could comment a little bit on the cadence and level of engagement you've had with the agency heading into the REMS update for FILSPARI, given the evolving landscape and what we've seen from a regulatory perspective in other cases in the sector. Thanks so much.
Speaker 3
Yeah, thanks for the question, Anupam. Certainly, we've been monitoring the overall landscape with regard to the FDA. Bill, why don't you comment on what we've seen with our programs?
Speaker 0
Yeah, certainly. What we've seen is basically through the lens of two sNDAs, both with the sNDA for the modification of the REMS frequency and the removal of the embryofetal toxicity REMS, as well as the sNDA for FSGS. Our interactions have been progressing as we'd expect, and the back and forth has been very similar to what we experienced just last year with the NDA for full approval in IgA nephropathy. The frequency of interaction, the types of questions, it feels just the same. We certainly see, on our part, a very engaged and active review team.
Speaker 3
Thanks so much for taking our question.
Speaker 0
Thank you.
Speaker 9
Our next question comes from the line of Laura Clague from Wedbush. Your line is open.
Good afternoon. Thank you very much for taking the question. Another regulatory question, if I might be able to. I'm kind of curious at what point you would gain insight into the timing of the advisory committee panel meeting. It sounded from the prior comments that the interactions are occurring on a regular cadence as would be anticipated, but we detected another possible shift in CDER reviewer headcount. Just trying to understand, is there any expected timeline that you would receive notice for the advisory committee meeting? Thank you.
Speaker 3
Thanks, Laura, for the question. Bill, why don't you take that one?
Speaker 0
Certainly. We don't know at this stage what the date of the advisory committee will be, but once we do know it, we will certainly provide that update. Given that we have a PDUFA date of January 13, it's reasonable to anticipate that the advisory committee should be taking place sometime in Q4.
Thanks very much.
Thank you.
Speaker 9
Next question is from Tyler Van Buren from TD Securities. Your line is open.
Hi, this is Frances on for Tyler. Congratulations on a really amazing quarter. I am just wondering, what would it take after the REMS PDUFA to get the REMS essentially removed entirely, and on what timeline would you expect that to be?
Speaker 3
Okay. Thanks, Bill. Another one for you.
Speaker 0
Thank you for the question. Our strategy has always been to have the ultimate removal of the REMS. Per our prior interactions with the agency, we've always approached this as a two-step process, seeking first to lessen the testing frequency and then full removal as a second step. Historically, the FDA has been anchored on completing our PMR following 3,000 patients for two years, and we're going to continue the dialogue to evaluate opportunities to potentially remove the REMS ahead of that following the PDUFA date on the 28th of this month.
Speaker 3
Thank you, Frances. Next question.
Speaker 9
Next is from Nivi Nehra from Guggenheim Securities. Your line is open.
Hi, this is Arsenie on for Wamel. Thank you for taking our question and congrats on a great quarter. You presented new data from the article and SPARTAN studies at recent conferences. How are these data being received by the nephrology community, and do you anticipate further real-world evidence or biomarker data to support FILSPARI's positioning as a disease-modifying therapy?
Speaker 3
Great. Thanks for the questions. Jula, why don't you comment on what your team has been hearing when the data have been presented?
Speaker 8
Yeah, it's been received very positively. There's a lot of excitement about the data that we're generating, both, as you mentioned, in combination with SGLT2 inhibitors, that it's safe and we have good efficacy when used in combination. To your point around the SPARTAN study, we've been increasingly showing data showing the effect of FILSPARI on reducing disease-modifying biomarkers such as soluble CD163, which we released last year. As I mentioned on the call, additional data of reducing inflammation, B-cell activation, and complement activation. People are now starting to think that FILSPARI works directly within the kidney on reducing the inflammation in the kidney, and that is part of the role for why it's nephroprotective over the long term. Your second part was additional data. We certainly want to validate this.
We have a large Phase 3 study from which we have biomarkers that we can confirm and validate this, and we plan to present that data in future congresses.
Speaker 3
Thank you.
Speaker 9
Next question is from Mauri Waco from Jefferies. Your line is open.
Hi, this is Farzina from Mauri. Congrats on the solid 2Q number. Is there more perspective that you can provide on the dynamics and breakdown of the growth contributions from stocking, new patients, and persistence rates, and how could this look for the rest of the year?
Speaker 3
All right, Farzina, thanks for the question. Peter, I'll turn that one to you.
Speaker 1
Yeah, thanks for that question. Indeed, very strong performance both on the demand side as well as the revenue side. I think your question is mainly referring to the revenue side. We didn't see stocking. This was really like performance-driven revenue growth.
On the persistence rate and the new patients versus the carryover patients from the last quarters.
Speaker 3
Yeah, the persistence rate continues to be very high. There's been no change in what we've seen, and I think as Peter mentioned in his prepared comments, really all of the fundamentals that we look at, particularly as lead indicators of performance moving forward for the rest of the year, all remain very strong. It really is the underlying performance. As you would imagine, over time, much of the volume becomes continuing patients, you know, and growth from adding new patients. That's precisely the dynamic that we're seeing, and we expect that to be sustainable for the foreseeable future.
Speaker 9
Next is from Miguel Nochomovich from Citigroup. Your line is open.
Yeah, hi, thank you. I had a question on FSGS. As you may know, there was a paper published in October 2024. It was called "Proteinuria as an Endpoint in Clinical Trials for FSGS." They make a very specific point in there with respect to the reference to a quote "sustained CR." I'm just wondering if you could comment as to your understanding of what that means and whether it's associated with any particular time point or not. I know that in the study, you obviously had a 2.5 times better CR response rate versus irbesartan in the double-blind period. I'm just wondering if that is consistent with the definition of sustained CR, or if sustained CR refers to a specific point in time as opposed to over the entire course of the trial. Thanks.
Speaker 3
Thanks for the question. Jula, I'll turn that one to you.
Speaker 8
Yeah, thanks for the question. I was part of that manuscript, so happy to answer it. Complete remission can occur at one point in time, or it can be durable. We didn't define exactly what that meant, but I can tell you when we look at the DUPLEX data, and you mentioned the 2.5 times greater rate of complete remission, what we commented, at least within the DUPLEX manuscript in the New England Journal, is that 85% of those patients stayed below their baseline rates of proteinuria, so had some level of durability of complete remission response. We did look at it at any point in time during our DUPLEX trial data. We haven't specifically elucidated others other than what we have published to date. If there's additional questions around durability, there are lots of ways in which you can define that.
Our focus is on what the FDA wants, and that's what we've given to them. Any questions that they have around additional ways in which we can analyze the data, we certainly can respond to them around that.
Speaker 3
Maybe just additional things that I'll add. Yugal, sorry. Sorry, Yugal. Anything you wanted to clarify before I add something else?
That was a super, super helpful answer. Thanks. Yeah.
That's great. While this isn't specific to complete remission, if you look at our corporate deck, slide 31, you'll see that the patients that were able to get to FPRU, which was the pre-specified endpoint within our trial, that is sustained whether you look at it at nine months or two years, and the treatment effect continues to be consistent and significant. I think, in the ways that we've looked at, as Jula's talked about it, you have a reduction in proteinuria that is rapid, that is sustained, and that is consistent. The other thing that I'll point out about that publication, which was really informative, it occurred before Paracel. What's important is to make sure that we recognize that the analyses and conclusions from Paracel are the largest, they reflect the largest analysis of registry data from within FSGS.
It's certainly consistent and informative, but it's really important to keep in mind that the thresholds that were put forth in Paracel represent a very robust data set.
Got it. Thank you.
Thank you.
Speaker 9
Our next question comes from the line of Mohit Bansal from Wells Fargo. Your line is open.
Okay, thank you very much for taking my question, and congrats on all the progress. I would love to understand, do you have a good cadence of patient start forms here? Can you comment on what is the conversion rate of those forms to the number of patients that are on the drug, and how would you characterize where you are in terms of the penetration in this market, and how do you see it evolving now with more competition, but at the same time, more awareness with that competition? Thank you.
Speaker 3
Okay, great. Thanks, Mohit. I think we've got three questions. Peter, why don't you take all of those: conversion rate, penetration rate, and then how you think that will evolve with the market? I think we got them.
Speaker 1
Yeah, let me start. Thanks, Mohit, for that question. Let me start with the last part on the evolution of the market and how we see that. I think the market we have spoken about in the past, especially after our full approval, we anticipate that the market potential is about 70,000 addressable patients for FILSPARI in the U.S. About 70% of those patients have elevated proteinuria levels, but below 1.5 grams per gram. If you talk about penetration, it really depends on what segment you are talking about. Are you talking about the segment 1.5 or greater, or are you talking about the full market potential? After our full approval and no longer a proteinuria threshold in our label, we have now access to the broader market. I think that's really where the opportunity resides and will continue to reside as well.
In that context, I'm really happy with the progress that we are making, that we are seeing also, and I mentioned that in the last earliest call as well, the median proteinuria level by patient start form is moving to the left. What I mean is that it's now below 1.5, and it continues to trend in that same direction. I think we are entering a market segment where most of the potential is, and that allows for sustainable growth as well. That's how we see the market evolving as well as the penetration component. With regards to conversion, I think based on my experience in rare disease, as well as what I've seen from rare disease benchmarks, I would say that we are at the top end best practice on conversion, what you would expect in rare disease.
Speaker 3
Thanks, Peter. Mohit, one thing that I'll add, just if you look at the cumulative PSFs from initial approval, we still have less than 10% of the overall addressable population addressable. We've had very strong performance, and this is one of the strongest rare kidney disease launch uptakes over the last five years. That penetration rate reflects that we have significant room to grow. This is when we talk about the sustainable growth that we expect. It's because we've been successful, and it represents a relatively small penetration rate to date.
Got it. If I could ask a follow-up, I mean, from the patient start form point of view, given that there is another player on the market, how should we think about the patient start form cadence going forward, given that you have a competition here? That's the part I would love to understand and level set expectations here. Thank you.
Yeah, we've not provided guidance. I just want to be cautious of not doing that, but I will reflect on what Peter has talked about in the last two quarters, which is that the new baseline for new patient start forms is around 700. We clearly achieved, exceeded that in this first quarter of having a direct competitor and growing treatment options within this space. We expect this opportunity to continue, and Peter can certainly talk more about the dynamics that we expect with a new treatment option within the endothelin class. Peter?
Speaker 1
Yeah, thank you, Eric. Just to put an exclamation point on some of the points that you made, I think, Mohit, within the evolving treatment paradigm, we delivered our strongest quarter to date, both from a demand perspective as well as from a revenue perspective. Even though it's early days since we saw some of those new entrants coming to the market, everything we have seen so far is consistent to our expectations. New classes, new therapies coming to the market, one, further reinforces the urgency to treat those patients earlier and more aggressively, and two, it also grows the endothelin market. I think the market is big enough to, to your earlier point, other products will be used, but given the strong profile of FILSPARI and the recognized profile and the long-term data that we have, I'm confident that we will remain the market leader.
Got it. Helpful and congrats again. Thank you.
Speaker 3
Thank you.
Speaker 9
Our next question comes from the line of Bahar Agrawal from Cantor. Your line is open.
Hi, thank you for taking my questions and congrats on the quarter. Another on FSGS. In the Phase 3, I know you have disclosed eGFR at the end of the trial, but we have not seen the eGFR curves in FSGS. Maybe even qualitatively, could you comment on what to expect when the curves will be presented during the, or could be presented during the ADCOM, and the latest thinking on what the FDA would like to see on eGFR here? Secondly, on IgAN, if you could comment on the growth to net trends you saw in 2Q and expectations for the rest of the year. Thank you.
Speaker 3
Okay. Jula, why don't you take the two questions on eGFR, and Chris, you can take the growth to net question.
Speaker 8
Yeah, certainly. With the PROTECT analysis and recommendation and the move to focus on proteinuria as a surrogate endpoint for full approval in FSGS, we haven't spent much time publishing our eGFR data, and I don't anticipate that to be a large focus of our advisory committee. Of course, we certainly can show the curves. It's consistent with what you would anticipate. We had a washout of RAS inhibitors for two weeks, and then we initiated the two therapies, FILSPARI and irbesartan. We had an acute decline in eGFR, and then it's relatively stable thereafter, or you have some decline, as you can see by the absolute change over time, but nothing surprising if we show our eGFR curves. It just hasn't been our focus because we're moving to proteinuria, which is a better surrogate with less variability for predicting avoidance of kidney failure. That's been our focus.
Speaker 3
Prakash, I realize we mentioned FDA has not requested EGFR as part of our Type C meeting. I think it's not just reflective of what we've interpreted from Paracel, but specifically the area of focus from our Type C meeting that we've discussed previously. Sorry, Chris, go ahead.
Speaker 7
Prakash, thanks for the question on growth to net. As you would expect, we did see some relief this quarter relative to last quarter once we got through the typical beginning of the year dynamics. As we look ahead, we may see some incremental increases in discounts in 3Q, 4Q, but we're squarely in line with where we've guided for the year and being in the low 20%. Everything is shaping up as expected.
Speaker 1
Thank you.
Speaker 3
Thank you.
Speaker 9
Next is Tyson Zemanski from Bank of America. Your line is open.
Speaker 3
Good afternoon. Thanks for taking our question and congrats on the progress. Maybe at this point in the launch, do you have a greater sense of where the headwinds or bottlenecks are in terms of uptakes, whether it's on the prescriber side or patient, payer, logistical, or administrative? Just trying to get a sense of what some of the potential near-term levers are. Just as a quick follow-up to one of your earlier comments regarding these new segments of the market, is there a meaningful or measurable difference in the use of drug between these new patients who may be a little bit healthier or, you know, not as advanced? Thanks.
Speaker 7
Jason, thanks for the questions. Peter, why don't you take both of those?
Speaker 1
Yeah, thanks, Jason, for that question. With regards to your first question on potential bottlenecks, I think, most of all, I'm really pleased with the progress that we are making. If I have to think, when I think about our launch in the last two and a half years, I think the main issue we had to overcome was the urgency to treat and change treatment for those patients. What really will help is more treatment options coming to the market together with the KDIGO guideline to reinforce the same methods that patients should be recognized and treated more aggressively early on. I think it's going to help to further develop this market. I think this is really a market in development.
On your second question, with regards to the new patient segment, like the lower proteinuria, still elevated proteinuria levels but lower than 1.5, I think this is a segment where I really see an opportunity for us with the REMS modification, as that is more in line with the clinical practice of three monthly monitoring of lab values. Like the higher proteinuria level patients, like 1.5 or greater, it is not uncommon that they actually do monthly lab testing. When you talk about patients at the lower proteinuria levels, it's more common that they are seen every three months by the nephrologist, and as part of the routine monitoring, they do the measurements. I think our REMS modification is right on time where we are in the launch. That's where I see the opportunity moving forward.
Speaker 3
Got it. Thanks for the color.
Speaker 1
Thank you.
Speaker 9
Next is from Greg Harrison from Scotiabank. Your line is open.
Hi, everybody. Thank you for taking our question and congratulations on the quarter. This is Joe Thomas on for Greg. I'm just thinking on the patient start forms in the quarter. I wonder if you'd be able to comment on the distribution as the quarter went along. Did you see any lumpiness or any acceleration as the quarter was going, and how should we think about that going forward? Thank you.
Speaker 3
Joe, thanks for the question. Peter, why don't you take that one?
Speaker 1
Thanks, Joe, for that question. As I mentioned earlier, I'm really pleased with the strong performance this quarter. As is typical in rare disease, there is often variability month over month, but overall, what we have seen is consistent demand during the quarter, and that continued in July as well.
Great. Helpful. Thank you.
Speaker 3
Thank you.
Speaker 9
Next is Alex Thompson from Stifel. Your line is open.
Great, thanks for taking our question. Maybe shifting over to Europe, to the extent to which you have visibility on CSL Vifor launch, when should we expect to see meaningful royalty revenue ex-U.S.? Thanks.
Speaker 3
Yeah, thanks so much, Alex, for the question. We do want to defer to CSL Vifor to comment on their performance. Chris, I'll let you discuss a bit more on expectations for royalties.
Speaker 7
Yeah, happy to do that. Thanks, Alex. I think, as Eric mentioned, we'll defer to CSL Vifor on any kind of guidance. As you would imagine, they're now through the early stages of going through the country-by-country process. As that happens and they gain reimbursement, we would expect revenues to begin picking up overseas and in return, royalties coming through to us. More to come as CSL Vifor continues to navigate that and report. As soon as we have more that we can share, we'll be happy to do so.
Great, thank you.
Speaker 3
Thank you.
Speaker 9
Thank you. Ladies and gentlemen, this concludes the question and answer session of today's conference call. I'll hand the call back to Nivi.
Speaker 10
Thank you, everyone, for joining today's call. Have a great rest of your day.
Speaker 9
This concludes today's conference call. Thank you for participating. You may now disconnect.