Good day, and welcome to the Travere Therapeutics First Quarter 2023 Financial Results and Corporate Update Conference Call. Today's conference is being recorded. At this time, I would like to turn the conference call over to Vice President of Investor Relations, Naomi Eichenbaum. Please go ahead, Naomi.

Thank you. Good afternoon. And welcome to Travere Therapeutics first quarter 2023 financial results and corporate update call. Today's call will be led by our Chief Executive Officer, Dr. Eric Dube. 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, Senior Vice President of Research and Development will join us for the Q&A session. Before we begin, I would 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, May 4, 2023, 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, Naomi, and good afternoon, everyone. The first quarter of 2023 has been one of the critical milestones representing significant progress across the organization. These advancements have positioned Travere for sustained growth led by the ongoing launch of FILSPARI in IgA nephropathy and bolstered by the continued progression of our pipeline. The most notable achievements in the quarter was the US accelerated approval of FILSPARI or Sparsentan for the reduction of proteinuria in adults with primary IgA nephropathy or IgAN at risk of rapid disease progression. The approval of FILSPARI marked the first and only non-immunosuppressive therapy for the reduction of proteinuria in IgAN. While we are only in the early stages, the commercial launch is progressing very well and in line with our expectations. Today we will focus on the important takeaways from the first six weeks. Though I'm very pleased with the early demand and the commercial organization's executions, which instills confidence that we will effectively position FILSPARI to meet or exceed our internal goals for the year. Furthermore, we were very excited to see the interim results from the PROTECT study published in the Lancet. These data further elucidate the clinical profile of FILSPARI demonstrating a greater than threefold reduction of proteinuria from baseline after 36 weeks of treatment compared to the active control irbesartan. The compelling dataset support our confidence in a positive outcome from the two-year of secondary endpoints in the fourth quarter of this year. Overall, it was a great quarter for our efforts to establish the foundation for FILSPARI to become a new treatment standard in IgAN for the addressable population. Earlier this week, we were disappointed to report that our Phase 3 DUPLEX Study of sparsentan in FSGS did not achieve the primary efficacy eGFR endpoints. FSGS is a very difficult…

Thank you, Eric, and good afternoon, everyone. I'll start by highlighting our continued efforts to support the awareness and education of the FILSPARI clinical profile. As Eric mentioned earlier, we were very pleased with the recent publication of the interim results from the Phase 3 PROTECT study in the Lancet. The rapid publication in this renowned Journal speaks to the scientific relevance and strength of the PROTECT interim results in IgA nephropathy. The publication serves as a great platform to showcase the interim results from PROTECT, the largest interventional study of its kind in IgA nephropathy. The published results detailed the rapid and sustained reductions of proteinuria seen in PROTECT along with the inclusion of significant new data on complete and partial remission. The new data highlighted that after 36 weeks of treatment in PROTECT a significantly greater proportion of patients on FILSPARI achieved complete and partial remission of proteinuria. As recently published, most high risk IgAN patients will face kidney failure within their lifetime, and reducing and maintaining lower thresholds of proteinuria particularly to levels less than 0.5 grams per day can impact long term kidney outcomes. We also saw encouraging early trends on important kidney outcomes. Here approximately half the number of patients treated with FILSPARI reached the confirmed 40% reduction in eGFR from baseline kidney failure or all-cause mortality compared to irbesartan. Furthermore, important data were included that support our belief and the primary efficacy objective of the Phase 3 PROTECT study that optimally antagonizing endothelin-1 and angiotensin-2 with sparsentan may lead to protective effects in the kidney structure and function beyond hemodynamics. Specifically, the authors through the conclusion that the proteinuria lowering effect of sparsentan is unlikely to be attributable to differences in blood pressure especially given the large differences in proteinuria reduction relative to minimal…

Thank you, Jula. I am pleased to report that we are making great progress in the early days of FILSPARI launch. Our results in the first quarter included only six weeks, and we are in line with our expectations. We are encouraged with the strong level of interest and engagements that we're seeing across stakeholders, including patients, physicians, and payers. Let me reflect on our progress and some of the metrics that we saw in the first six weeks of approval until the end of Q1. Since our approval in February 17, we have remained focused on our three longest priorities. Educating nephrologists on the efficacy and safety profile of FILSPARI enabling broad patient access by securing reimbursement coverage and ensuring that both patients and physicians have a positive first experience with FILSPARI. First, looking at our physician education efforts. Our commercial field team of over 80 seasoned professionals is successful in getting access to nephrologists and educating them on the FILSPARI label. Our strategy is to ultimately reach the universe of 6,000 nephrologists representing roughly 85% of the addressable IgAN patient population for FILSPARI in the US. We have face-to-face interactions with over 2,500 of these nephrologists in the first six weeks. These engagements are aligned to our profiling insights and we are reaching those nephrologists who have been and we believe will be the early adopters. The reception to FILSPARI's efficacy and safety profile has been strong. Physicians consistently mentioned the impressive proteinuria reduction with FILSPARI and the importance of having the non-immunosuppressive agent therapy. And we are excited to see a strong increase in brand awareness, now that our team is actively discussing FILSPARI with nephrologists. As mentioned on the last earnings call, we received our first patient start forms in the first working day after approval,…

Thank you, Peter, and good afternoon, everyone. Our first quarter performance was highlighted by continued strong execution across the organization as well as the strengthening of our financial position. For the first quarter of 2023, net product sales were $50.3 million compared to $46.4 million from the same period in 2022. The increase is primarily attributable to the first reported sales of FILSPARI and growth in sales of the bile acid portfolio. As for FILSPARI, we utilized the sell-in methodology where we recognize revenue when products are delivered to our small network of specialty pharmacies. As you heard from Peter, that has resulted in a large amount of the FILSPARI sales recognized this quarter being related to stocking and anticipation of demand. For the legacy products, as we've seen in previous years, gross to net discounts in the first quarter were higher as a result of insurance coverage changes in the beginning of the year. As we move through the balance of the year, we expect these to normalize. But they will continue to be higher for the Thiola business than in previous years. During the quarter, we also recognized $6.7 million of license and collaboration revenue. This compares to $2 million in the same period last year. The increase is primarily driven by the sale of drug product to our partner CSL Vifor as they prepare for a potential launch of FILSPARI in Europe. This activity also resulted in a nearly proportional increase in cost of goods sold for the quarter. Research and development expenses for the first quarter of 2023 were $59.9 million compared to $56.6 million in the same period in 2022. The difference is largely attributable to the continued advancement of our sparsentan and pegtibatinase clinical programs including clinical trial expenses in manufacturing and increased headcount.…

Thank you, Chris. We began the new year with the first FDA approval from our rare disease pipeline. The accelerated approval of FILSPARI marks the first and only non-immunosuppressive treatment indicated for the reduction of proteinuria in patients with IgAN. And I am very pleased with the execution so far in the launch. Most importantly, following the first six weeks of launch, we are well in line with our expectations for demand, patient access, and reimbursement, and I'm very pleased with how our team is executing on our launch plan. We will remain focused on building momentum as interest amongst nephrologists continues to grow and we look forward to providing regular quarterly updates on the FILSPARI launch. We also have a number of exciting milestones ahead of us this year. We look forward to the topline results from the PROTECT study in the fourth quarter of this year and remain highly confident in the final results, achieving a statistically significant treatment effect on EGFR, as we know, physicians are excited to see those data. We believe positive results will lead to traditional approval of FILSPARI and catalyze the next phase of growth. Furthermore, we are pleased with the ongoing EMA regulatory review and look forward to a potential approval of sparsentan for IgAN in Europe in the second half of the year. And finally, we are very excited about the opportunity in HCU. The HCU community has been highly underserved and they are eagerly seeking effective treatment options. Pegtibatinase has the potential to become the first disease modifying therapy for this population, if approved, and we look forward to providing an update on the program later this quarter. Now, let me turn the call back over to Naomi for Q&A. Naomi?

Thanks, Eric. Operator, can we now open the line for Q&A?

[Operator Instructions] We'll take the first question from the line of Maury Raycroft from Jefferies. Maury, your line is now open.

Hi, congrats on the progress with the launch and thanks for taking my questions. Based on the Lancet paper PROTECT is powered at 90% to detect an underlying treatment effect of 2.9 mil per minute per year, so that translates to 5.8 mil per minute over a two-year treatment period. Can you clarify if that is the delta versus irbesartan or is that only the sparsentan treatment effect?

Maury, thanks for the question. I will turn that over to Jula.

Thanks, Maury, for the question. So, to clarify, the greater than 90% power to detect a difference in slope of 2.9 mils per minute per year with 380 patients. So just to give some more color. This is based on historical data and achieving a 30% difference in proteinuria and recall, we achieved a 41% relative reduction in proteinuria giving us a geometric mean ratio of 0.59%. So when you put that on the incur curve, it predicts a slope difference close to what we originally modeled. And it shows a very high positive predictive probability for a difference in eGFR slope. Even with a modest sized trial and I'll point you if you want more details, I'll point you to the anchor appendix so that you can actually do some of the analysis yourself.

Got it. That's helpful clarification. And based on the new DUPLEX data and the view that IgAN is a progressive disease. Is there anything additional you can point us to for how we should think about irbesartan arm treatment effect size on eGFR and PROTECT?

Well, remember the irbesartan in PROTECT was already essentially optimized on RAS inhibition. They were at least 50% label, maxi-tolerated RAS. So essentially, they were treatment failures because they had persistent proteinuria despite this. And there was still an incremental reduction in proteinuria on those ones, but we had a 41% relative reduction in proteinuria compared to the irbesartan. So I would imagine that we can anticipate those on irbesartan to progress time we've seen in other studies may be slightly better. And in the TarPeostudy, they progressed at 6 ml per minute per year. Maybe they'll do slightly better than that just because we had a slight reduction in protein, but that is what I would say, compared to the historical control.

Got it. That makes sense. And maybe last quick question. Similar to DUPLEX, I'm wondering do you have any feedback from FDA on whether it would be okay if you miss on total slope what hit stat on the chronic slope for PROTECT?

Bill, why don't you take that question?

So we don't have a specific dialog from the agency addressing that with PROTECT in the discussions around the design of the DUPLEX study, they did say that in the end, while the study is designed around Total slope first and chronic second, they certainly want to look at all of the elements of the study. And I think that, my expectation is they'd be consistent with each program with that type of approach.

Got it, okay. Thanks for taking my questions.

Thank you, Maury.

We will take the next question from the line of Greg Harrison from Bank of America. Greg, your line is now open.

Hi, good afternoon. Congrats on the FILSPARI number and thanks for taking the questions. Are you able to give any additional color on what part of the $3 million sales number was patient demand and maybe how many patients are on treatment and then what portion of the 146 patient start forms have transitioned into the pain patients or at least maybe what should we expect that rate to be over time?

Greg, thank you for the questions. We would be in a position to be able to share as we mentioned at the approval to be able to talk about the patient start forms as well as revenue but we recognize certainly that early on in any phase of launch for specialty medicine, you're going to have variability in terms of the stocking as well as how quickly you get that through. And I think as both Peter and Chris mentioned, it is going to take some time to have that. While we did have some re-orders or orders that reflect underlying demand, you can largely think about that $3 million as channel stocking for the first quarter. And we are not going to be providing any specifics at this point with regard to the breakdown of or conversion of patient start forms to reimbursement. They are very in line with our expectations. We're really pleased with all aspects of the launch so far, but those metrics really are lumpy in the first part of the launch. We want to make sure that we can provide a consistent set of metrics over time that are going to be predictable and consistent throughout the launch. So stay tuned, we may evolve and being able to share some of that is we have an underlying trend emerge in the launch, but at this point, I would say that you should rely on the 146, reflecting the underlying demand from nephrologists.

Okay, fair enough. And then the 146 number, it's pretty impressive. I think it's above most people's expectations. Do you think that reflects at all a bolus of patients that was maybe waiting for treatment or do you expect more of a steady ramp throughout from here?

Peter, why don't you take that one?

Yes, happy to do that. Thanks Greg, for that question. Yes, you don't really see a bolus. And you have to realize IgA nephropathy still a rare disease even though every nephrologist has at least a handful of IgA nephropathy patients. It's not like a physician has top of mind like, hi, all those patients should come in at a certain date. So I have to say, especially after spending some time in the field and seeing how busy those community practices are, IgA nephropathy for us is top of mind. For nephrology in all those patients they are serving, it's only a small fraction, so I don't think they have some bolus. We are happy with the steady demand that we are seeing and there is a big demand as well. But I wouldn't say there is a bolus of patients that you see initially, I think you will see a constant steady growing demands with regards to IgA nephropathy as patients are coming into the office as we progress in advance.

Okay, great. Thanks for taking the questions.

Thank you, Greg.

We will take the next question from the line of Joseph Schwartz from SVB Securities. Joseph, your line is now open.

Hi, thanks so much. I was wondering if you can give us any insight into how many physicians have written a FILSPARI prescription to date and if you can describe the earliest adopters for us?

Peter, why don't you take that question?

Yes, at this point, to years earlier point, we won't be disclosing how many prescribers we have. We have seen repeat prescriptions already. I think it's in line with what you may have expected given the 146 patients start forms. We're very pleased with the way they're receiving the product right now. And to your point, what is the profile of the prescribers so far? Well, we have really been targeting based on three aspects. One is volume, patient volume in the clinic, as well as the physician's behavior in adaptation of new innovation as well as the influence. And we see that especially the patients -- the physicians in large community practices are key to prescribe FILSPARI.

Okay. Thank you. And then maybe a question on your HCU program. We hear that these patients can be somewhat elusive. So I was wondering if you can describe your relationship with the patient community and the physicians that treat them and how has that evolved since running the compose study, how challenging was that to enroll? And do you think -- how much of a challenge you think it could be to enroll a larger Phase III study?

Yes. Joe, thank you for the great question. I'll start by sharing a little bit about the relationship and how the community has evolved, and then I'll ask Jula to share some of the insights that her team has gathered in conducting the Compose Study. This is a patient community that really has been underserved. And when we took over the program, many of them were actually served by connecting with phenylketonuria or PKU community because of a lot of the similarities, and how the conditions are managed. But I think as we've started to really build our relationship with them, they really start to build their own community online as well as with kind of the standard patient advocacy organizations, both here in the US as well as abroad. And, I think that we're starting to see a much more concerted and organized effort to articulate what the needs of that community are with regard to earlier diagnosis improving newborn screening, helping to understand better management of the disease, as well as I think for us educating about the importance of engaging in a clinical trials as a potential for innovation in the future. So, I think largely we've been really pleased with how quickly the community has evolved. And I think we've really gained a lot of good learnings with regard to clinical trial enrollment. And with that I will turn it over to Jula to share more.

Thanks, Eric. Well, any rare disease, it can be challenging to recruit because there's very few patients per site. So, it can take a bit longer and you often have to go to where the patients are and you really do need to engage with your advocacy partners and with the patient community to understand what's important to them. Simplify the trial design and provide them a lot of support. And so that's what we're doing. Moving forward, I would say also importantly we have significant engagement with the key opinion leaders to make sure that what's important to them and their patient community is what we incorporate into the design of the study. And then we also have a natural history study that helps us with having access to patients who if they're interested in participating that can provide us with additional patients that can help to enroll a bit quicker.

Thank you for the insights.

Thanks, Joe.

We will take the next question from the line of Carter Gould from Barclays. Carter, your line is now open.

Hi, this is Leon Wang on for Carter. And thanks for taking my question and congrats on the results. So, on FILSPARI, any early signs of the patient profile that docs are prioritizing versus those that they may be waiting for more confirmatory eGFR data or any profiles of docs that maybe perhaps waiting for the data and not susceptive to show a launch?

Yes, thanks for the great question. Maybe I'll start by saying with any launch, you typically will see a spectrum of adoption by physicians where you have some that are early adopters and those that are waiting that. So it's not surprising that there will be some physicians that want to wait. What I will say is that we're very pleased and the performance thus far from physicians is absolutely in line with our expectations, and also in my experience with launches. I'll ask Peter to share a little bit more about the types of patients that we're seeing, prescribed FILSPARI in the first six weeks as well as the profile of physicians that we see adopting.

Yes, I think, happy to provide some color on the basis that we seeing. So the majority, the vast majority of the patients are those patients that are on the rapid pace of progression which consistent has high proteinuria levels. Many of those are above 1.5, but we also have some restrictions for patients with lower proteinuria levels at 1.5 but have additional indicators for rapid progression. So I think largely in line with how the indication is written, nearly above 1.5 with some so below 1.5 gram.

Maybe the other thing, Peter that I'll add is that the payer mix is very consistent with what we had assumed with the majority of these patients having commercial insurance. So I think a lot of the work that Peter's team did to really profile what this looks like, what the launch uptake could look like, is again very much in line with our expectations and planning.

All right. Thank you.

Thank you.

We will take the next question from the line of Liisa Bayko from Evercore ISI. Lisa, your line is now open.

Hi there, thanks for taking my call, and congratulations on the initial good start here. Just -- I know you wouldn't have this right now, but as we think about sort of later in the year, what kind of gross and net can we expect, and what would it be initially and I'm not sure about this quarter, but and then what do you think it will stabilize around?

Yes, great question, Liisa. Certainly as you alluded to the first part of a launch is going to be quite lumpy. So we've been reluctant to provide any estimates at this point, but I'll ask Chris to comment on where we think we may be landing once we get to that steady state.

Yes, thanks for the question, Liisa. Really a stable state. We're going to be looking at mid to high teens. And I think what we're seeing now is reflective of us getting there, once we do get to that stable state. So, no change from our expectations on that point.

Okay. And then just back to the PROTECT and your powering. So, Jula, can you describe how you saw, you saw a 2.9 that you're powered for 2.9 milli liter difference was slope that was assuming 30% difference in proteinuria but you actually got a bigger delta than that. So now you should have a greater difference. Is that the right way to think about that? Can you just -- I didn't hear everything you said, it was little confusing?

Yes, Jula, would you like to take that?

Well, our initial power calculation was based on historical data. And then you can map it based on the incurred data. So based on incurred data we fall in line with our original power calculations to be able to predict a statistically significant and clinically meaningful effect at two years. The other thing I do want to add to this is that as part of our review for accelerated approval, the FDA was very focused that we'd be able to confirm our benefit after the two years. So they asked us the likelihood of achieving statistical significance, both on the chronic and total slope endpoints for the two year, so we provided conditional power calculation that looked at our available eGFR data at the time of the interim as well as the information from the trial level analysis to address their requests, and importantly the conditional power calculation provide a very high level of confidence on achieving statistical significance at the two year confirmatory analysis.

Okay, thanks.

Thanks, Liisa.

We will take the next question from the line of Mohit Bansal from Wells Fargo. Mohit, your line is now open.

Thanks for taking our questions. This is [indiscernible] on for Mohit. Can you discuss whether you think naive patients or patients switching to FILSPARI is the bigger driver of demand in the first year at the launch? And then separately, on that 3% of insured lives being covered, is that ahead of your expectations and how could we think about that going from here, the type of cadence from quarter to quarter.

Sure. Peter, why don't you take those two questions?

Yes. Thanks for the question. So when you think about like where is the main demand coming from with regards to patients, naive or switch. It is very complex, like the majority, the vast majority of those patients have been on ACE or AR based in the past and are switched to FILSPARI. So I think that is quite consistent. I think ultimately you will start to see naive patients as well. I think it's a small fraction of the total patient population, because the majority of those patients are prevalent are already in the offices of the physician. So what we're seeing right now is, much of that phenomenon, patients that have not been limited to the proteinuria levels at position once. And sport works are being replaced with FILSPARI we're still squarely so that was the first part of your question. With regards to the second part of the 38% coverage, it's a good number and it's much in line with our expectation, especially if you take into consideration that there was only after six weeks or 38% coverage by March 31. So I think it's a good number that we feel quite proud of and I think it is at the high end, what you see with benchmark products.

Yes, Adam. Thank you for that. Peter. The only thing I would add with regard to actually both of those questions is the quality of the payer coverage. It's really important to think not just about coverage, what's the quality of the coverage relative to the labeled indication. And we're really pleased to see that there's a high degree of quality when we think about the access for patients aligned to the label and we do see a number of those payers that have stepped through ACE or ARB. But again, as Peter alluded to, the majority of these patients are already on ACE or ARB. In fact, many of these patients are referred to their nephrologists on ACE or ARB. So when we look at the actual quality of the coverage, it's not just 38%, but it's actually the quality of that access and we're really pleased. Again early days, but I think it's a great foundation upon which to build throughout the rest of this year.

Any further question, sir? We will take the next question from the line of Laura Chico from Wedbush Securities. Laura, your line is now open.

Thanks very much. I guess I wanted to talk a little bit more about the cadence of ordering here. I guess, Eric, maybe said differently. Could you just walk us through what are the expectations around the timing from receipt of a start form to when product is actually going to be a dispensed? Like what is the timeframe there? Sorry, if I missed it.

Yes. No, it's a great question, Laura, and it's important dynamic to think about any specialty launch where there is a range of timelines for from prescribing and I'll ask Peter to talk a little bit about what we're seeing and also what we expect to see throughout the rest of this year. Peter?

Yes. To respond to that, thanks Laura for that question. I think to Eric's points as is typical for many rare disease product launches. There is a wide range, I think to Eric's point, and it's typical for many rare disease product launches. There's a wide range of what I call the time to fulfilment especially in the early days as failure access may take longer. I would say, these 30 days the FILSPARI time to fulfillment is in reach but what is typical in rare diseases, which is typically in a 3 days to 60 days range I would say. We anticipate that this pull-through will decrease as we get more payer coverage.

And I'm sorry, Peter, Just to verify. You said it's ranging from 20 to 60. But over time when likely to be closer to a typical 30 day range. Do I have that correct?

Well, let's verify that Laura. I was talking about what is common in rare disease in general, but I will say we are in that race. It's more historically, what I've seen in rare disease and specialty launches. So I think it's not reflective of FILSPARI.

I think the important aspect, Laura to keep in mind is we won't provide any specific numbers because it really is only the first six weeks of experience after approval. What's important is, as we get more broader coverage and high quality coverage, that lead times should shrink and I think what's important in the experience that Peter's team has had, is that we've already -- one, we're off to a great start with regard to payer coverage and reimbursement, but we're already starting to see that average time to fill reduce and I think that as Peter's team continues to execute and we continue to get growing coverage, we'll continue to see that average time as well as the range reduce. So again really early days. So we don't want to give numbers because it is lumpy but the dynamics that we're seeing are exactly what you would expect to see with this successful launch.

Okay, that's helpful. And maybe I'll sneak in one quick follow-up. And again, apologies if I missed this, but did you quantify how many physicians are signed up for the REMS at this point?

Peter?

No, we haven't, we haven't given a number there, but we're very pleased with as with the patient start forms that we see steadily increase in REMS certifications and enrollment and I think it speaks to the assistance that they understand the value that FILSPARI may have for their patients, but also that they understand that the REMS process is relatively straightforward.

All right. Thanks, guys.

Thanks, Laura.

We will take the next question from the line of Tim Lugo from William Blair. Tim, your line is now open.

Hi guys, this is [Lachlan] on for Tim. Thanks for taking the questions. So I guess heading into the launch, one of the headwinds you guys had mentioned or potential headwinds was just that physicians wouldn't really have the data very well because there's obviously not much have been released. So I'm just wondering how much I guess how that has played into the launch so far. Have you seen that sort of affecting any of the interactions or the data which physicians are maybe starting to prescribe or is that really not affecting that, right, I guess compared to what you expected?

Yes, it's a great question, Lachlan. But I think first I'll point to what Jula mentioned in having a high profile publication of the interim data that I think really gives physicians a better understanding about the data but, Peter, why don't you share a little bit more about what you're hearing from your team about going through the data on FILSPARI?

Yes, I know, happy to do so. So indeed like nephrology in general is not as much inclined with innovation and maybe some other specialties given that social innovation to nephrology in general. And I think that's a phenomenon that we have seen with other nephrology launches in particular rare launches. To Eric's point, I think having new data and this is kind of like a rolling launch because we launched in the first six weeks without having a publication or without having sort of date, which is not very common to launch a product without that specifics. And so we launched basically on the PI. Also given the promotional restrictions in a support product in Brazil accelerated approval. But now that we have the lands of publication and start inclusion in medicine guidance like up to date and as Jula mentioned in her part of the prepared remarks, I think that should provide confidence and provides more insights in that process as well. So I think we -- I'm very pleased with what I'm seeing both in the intent to prescribe across but also the actual prescriptions being ready, and that's the 446 patients thought for that we were in Loreto. I think as we get more data and we have those publications, this will continue to bring confidence to the nephrology community and allow for continued and accelerated shifts.

Yes, I think that's absolutely right. Peter and I can share with you two maybe additional observations and like Peter, I spent quite a bit of time in the field meeting with customers. I think there's a real eagerness to understand the profile and the data to FILSPARI more so the publication and guidelines are going to really help provide some of that independent or third party perspective. But the other aspect is that it really helps understand the REMS better and the profile of a low rate of ALT AST elevation because I think in the absence of that information. It was hard for physicians to put into perspective what the level of risk really is and I think it's been very reassuring for physicians when they see the actual rates in the publication and in the label.

Got it. Thanks. And on the topic of reimbursement. Peter, I think you mentioned that most of it had gone through but there were some delays. The patients that you're seeking reimbursement for, I guess, to the extent that there have been delays, can you maybe talk about what pushback you're getting from payers?

No, I wouldn't say that. I mean, as you don't have inclusion in formulary yet. I mean, it goes through the prior authorization pathway and so that generally takes longer. I mean I think it's a common process in rare disease in particular. So I wouldn't indicate it as like particular obstacle that we are seeing for FILSPARI.

Got it. Thanks.

Thanks a lot.

We'll take the next question from the line of Vamil Divan from Guggenheim Securities. Vamil, your line is now open.

Great, thanks for taking the questions. I think most of mine on the launch have been asked and answered. But just one more, just in terms of the patients that are getting FILSPARIA so far, obviously, just early. I'm trying to get a sense that you mentioned sort of the ANR dynamic. But in terms of SGLT2s, if you can comment on neuro patients already on SGLT2s or not? And also curious with the label mentioning the greater than real 1.5 gram per gram. Is that sort of a metric that physicians seem to be sticking with? Or are they just using their judgment, and maybe patients are even below that threshold? And then the second question is more on the expense side, I guess, for Chris, just how we should think about, especially SG&A spend this quarter? The first quarter was a little bit more than we were expecting. Is this sort of a reasonable amount to assume going forward?

All right. Vamil, thanks for the questions. Peter, why don't you take the first on the patients?

Yes, good question. Maybe I'll start answering the question by giving you a broader perspective on the patient profile because this is often the younger patient population. Like many of those patients are being diagnosed in their 18 or early 20s. And that's what we're seeing as well. Many young patients that are on the path of rapid progression and to your point, Greg, what we are seeing is many of the current available medications doesn't bring patients to the level to the target level that physicians would like to see. ACE and ARBs didn't do that. You have SGLT2. I think that's something that we mentioned as well and we see that increase utilization in SGLT2. The physician feel very comfortable in combining if needed or if appropriate with SGLT2 as it's mechanistically synergistic but also FILSPARI has that very rapid progression of 50% proteinuria physicians haven't seen risk medications and especially the not immunosuppressive nature of FILSPARI with or without combination with SGLT2 makes physicians very comfortable, especially when you talk about the human patient profile that have been decided to go of immunosuppression is not quick, especially for this patient population.

And Chris for expenses.

Yes, absolutely. Thanks for the question, Vamil. What I would point back to is in the prepared remarks you talked about for overall expenses. We anticipate moderate increases for the balance of the year and really when I think about the breakdown of SG&A and R&D. That's probably more pointed towards R&D as we look to continue both the DUPLEX and PROTECT studies that are going to continue on for the balance of the year, but then also the pegtibatinase work that's going to go into the potential initiation of a Phase III as well as the supply CMC work that all needs to be done to scale up for both Phase III and commercial. And so I think that's where you'll see likely the larger magnitude of increase comp for the year. I think from an SG&A perspective, there may be some modest increase from this point, but I wouldn't expect it to be of any significant magnitude and really what we've gotten to in this first quarter is the first time in which you had the full sales force fully in place doing all the promotional activity and putting that right investment behind FILSPARI to make sure we can position it appropriately for IgA.

Okay, great. Thank you.

Thank you.

We'll take the next question from the line of Alex Thompson from Stifel. Alex. Your line is now open.

Hi, great. Thanks for taking my questions. I got one IgAN question and one FSGS question. I guess on IgAN, I'll try to ask another sort of commercial dynamics question. I guess, given that you're starting by targeting a lot of higher volume prescribers. Can you talk a little bit qualitatively about whether the majority of the Start Forms that you're seeing so far is coming from a single physicians or multiple physicians writing multiple start forms for patients or is it broader than that? And then on FSGS. Can you comment on sort of historic flexibility within the cardio renal division and if there's any good precedents for them sort of looking towards subgroup analysis in rare diseases, especially. Thanks.

All right, Alex. Thanks for the questions. Peter, would you like to take the IgAN question?

Yes. Thanks, Alex. So if I understand your question correctly, your question was like, do you see mainly prescriptions from prescribers have had multiple prescriptions or more single and if it's mainly in the higher volume centers. I think it's early for me to give a specific statement on that. I think we see the majority of the prescriptions coming on from community centers, especially from larger community centers but we also see prescription from academic centers and we see a mix of physicians that have prescribed the single time or the second time. So, but again I think it's early days on prescribing this and describing this for the first six weeks. So I wouldn't read too much into it. We see a large prescriber base and we see both single as well as multiple prescriptions among those prescribers.

And Bill, why don't you take the question on regulatory flexibility?

Yes. No, happy to. I think the one that comes to mind quickly is Entresto for congestive heart failure was approved by cardio renal. I think in '21 if my memory is right and that was a drug that missed their primary endpoint, but the decision of the agency was that there was clear benefit and across the trial based on totality of evidence and unmet need that was something that they were interested in improvement. I think that there have been other instances across rare disease indications. And I think the most recent work that I read was in JAMA where they said about the past 5 years or 10 years about 10% of the drugs approved by the FDA were ones that missed their primary endpoint in their pivotal study. So it's not a norm but it's also not something that's unheard of.

And Jula, anything further that you'd like to add on that question?

I would also point to Fabry is another potential indication for Migalastat to look at another reference.

Great, helpful. Thanks so much.

Thank you.

We will take the next question from the line of Ed Arce from HC Wainwright. Ed, Your line is now open.

Great. Thanks for squeezing me in here. And congratulations on the early progress on the launch. I see here obviously first six weeks, the $3 million is as you said represents mostly stocking and 146 PSS mostly a demand and I recognize as you pointed out that it's highly variable at the beginning but I'm wondering as we get through the next few quarters and years, if there are specific launch metrics that you intend to report regularly, for example, we've already discussed sort of the fulfillment conversion rate or number of prescriptions or patients on drugs and then perhaps later on numbers around persistence or compliance rate and just -- so that's first. And then secondly, just wanted to ask as well on the readout later this quarter on HCU with the higher dose in the lyophilized formulation. The focus clearly is these partly on the efficacy look from that dose as well as the PK with the new formulation. But what other aspects to the data readout, could we expect later this quarter? Thanks so much.

Yes, thanks. Thanks, Ed, for the great questions. I'll take the first one. So I think we certainly are looking at a number of different metrics, and it's important for us to make sure that the metrics that we provide regularly are ones that we have confidence in the sort of trendability and the predictability. We believe that's why we focused on patient start forms and access because they really are robust predictors of underlying demand as well as the ability to pull through and have those reimbursed. I think as we look forward, you can imagine that there may there likely will be others like the persistence rates or the reimbursement rate and you can look to our commercial business where we have talked about persistence the high rate of persistence et cetera. So as we start to understand the underlying dynamics of the FILSPARI launch, we will look to evolve what those are, but again we want to make sure that we really focus on those fundamentals this year that we believe are going to be most important in the first year of launch. And then with regard to the readout of the cohort 6 in the Compose Study, Bill, I'll turn to you to provide some further perspective on what we'll be looking for, and possibly what we would be disclosing, but I will say we haven't yet committed to what we will disclose specifically. Bill?

Sure. The cohort 6, we utilized the highest dose-to-date on a per gig basis in the study in what we view as the final cohort in the Compose Study. It also gave us the opportunity to utilize the lyophilized formulation and evaluate that in patients. What we're looking for is the most predominant biomarkers is going to be the reduction in homocysteine urea or in almost total homocysteine overtime in the 12-week double-blind portion of composed. In addition to that, of course, we're looking at safety and tolerability. It's a Phase 1/2 to study and evaluating that for those individuals at that dose and those patients will rollover into the open label expansion that will give us the data then to select the dose and help us with the design of the Phase 3 study.

Sounds good. Thank you so much.

Thank you.

There are no further questions at this time. Ms. Eichenbaum, I will turn the conference back over to you for any additional or closing remarks.

Thank you everyone for joining us for our first quarter 2023 financial results call. We look forward to providing additional updates on our progress. Have a great rest of your day and thank you.

This concludes today's call. Thank you for your participation and you may now disconnect.