Scholar Rock Holding Corporation (SRRK) Earnings Call Transcript & Summary

Good morning, ladies and gentlemen, and welcome to Scholar Rock's call to discuss the U.S. approval of ISEMBYLD. [Operator Instructions] This call is being recorded today on Monday, September 14, 2026. I would now like to turn the conference over to [indiscernible]. Please go ahead.

Good morning. I'm Laurie Ekas, Vice President, Investor Relations at Scholar Rock. With me today are David Hallal, Chairman and Chief Executive Officer; [ Akshay Vaishnaw ] , President of R&D; Keith Woods, Chief Operating Officer; and Vikas Sinha, Chief Financial Officer. Before we begin, I'd like to remind you that during this call, we will be making various statements about Scholar Rock's expectations plans and prospects that constitute forward-looking statements for the purposes of the safe harbor provisions under the Private Securities Litigation Reform Act of 1995. Any forward-looking statements represent our views only as of today and should not be relied upon as representing our views as of any future date. I encourage you to go to the Investors & Media section of our website for our most up-to-date SEC statements and filings. With that, I'd like to turn the call over to David. David?

Thank you, Laura, and good morning. Thank you all for joining us for what is an extraordinary day for the SMA community. On Friday, we reached a defining milestone, the FDA approval of ISEMBYLD, our novel, highly innovative myostatin inhibitor that is now the world's first and only muscle-targeted therapy for children and adults living with SMA. Over the past decade, SMN-targeted therapy that have brought needed innovation to the SMA community by improving motor neuron Health. Yet significant unmet need remained as treatment for muscle, the principal organ clinically affected by SMA had gone unaddressed. With the FDA approval of ISEMBYLD, we are now ushering in the next phase of innovation in SMA treatment, bringing the first and only therapy designed to directly target muscle to the SMA community, and creating new possibilities for patients and families. I would note three important points with respect to this landmark FDA approval. First, ISEMBYLD as indicated for all patients with SMA, 2 years of age and older who are currently receiving an SMN2-targeted treatment. This broad label enables us to serve a significant population within the SMA community and advances our ambition that any patient who can benefit from ISEMBYLD should have access to ISEMBYLD. Second, the label reflects the compelling clinical benefits that ISEMBYLD can bring to children and adults with SMA. For patients receiving a chronic SMN2-targeted treatment in our global randomized, double-blind, placebo-controlled Phase III SAPPHIRE study, ISEMBYLD change the progression of SMA from a loss of motor function to a gain of motor function, specifically at the recommended dose of 10 milligrams per kilogram, ISEMBYLD delivered a robust, clinically meaningful 2-point improvement in motor function compared with patients receiving an SMN2 targeted treatment alone as measured by the gold standard Hammersmith Functional Motor Scale. Akshay will provide much more detail on the ISEMBYLD label and clinical data shortly. And finally, we are thrilled that our U.S. launch of ISEMBYLD is now underway. Our highly experienced U.S. team has worked with urgency on extensive disease education and awareness initiatives that have advanced the understanding of SMA as a disease of both the motor neuron and the muscle supported by a broad label, compelling efficacy and a well-characterized safety profile, we are exceptionally well positioned for a successful U.S. launch. We are poised to redefine the standard of care for people living with SMA as we begin to serve a steady and consistent number of new patients through the initial phase of the launch and for many years to come. Scholar Rock is operating from a position of strength as we enter a new chapter as a commercial organization. From a financial perspective, we exited the second quarter with $492 million in cash, cash equivalents and marketable securities. Also, with access to an additional $150 million from our debt facility, a priority review voucher that we intend to monetize and revenues that will now commence and grow, we are well positioned to fund our growth initiatives. They include the ISEMBYLD launch in the U.S., our global expansion to reach patients in Europe, Japan and up to 50 countries around the world and advance our robust clinical pipeline and innovative platform. With this strong balance sheet, we do not intend to raise cash through an equity offering at this time. Looking forward, now that our U.S. launch has commenced our opportunity with ISEMBYLD and SMA alone represents many years of sustainable growth as we begin to serve the estimated 35,000 people with SMA globally who are receiving an [ SMN targeted treatment ]. We are on our way to becoming the next global biotech powerhouse supported by bold science, innovative therapies, fully integrated global capabilities and exceptional talent. Before I turn the call over to Akshay, to further discuss the approval of ISEMBYLD, I want to express my gratitude to the FDA for their constructive and collaborative engagement throughout the review process. which helped bring us to this important moment. With that, I'll turn the call over to Akshay. Akshay?

Thank you, David. I'm delighted to be sharing news of the ISEMBYLD FDA approval with all of you today. This is a momentous milestone for Scholar Rock. After nearly 30 years of failed efforts across the industry to drug myostatin, today, we're the first company to successfully develop and secure FDA approval for a myostatin inhibitor. With that, let me share details of the comprehensive clinical program that supported the ISEMBYLD approval and the resulting FDA issued label. SMA is a rare severe neuromuscular disease resulting in irreversible loss of motoneurons and progressive muscle wasting leading to motor function decline. Patients experience muscle [ wasting ] that impacts all aspects of mobility and daily life, including basic functions like breathing, eating, dressing, self-care and walking. Affected children often require significant support and for many independent living in adulthood can be very challenging. Despite progress over the last decade with SMN-targeted treatments, SMA remains a devastating disease for too many children, adults and their families. The motor unit has two key components: motoneuron and muscle. Given that motor function depends not only on neuronal signaling, but also on muscle responsiveness, approaches that target muscle from the start have been urgently needed. With that, let me share details of the comprehensive clinical program that supported the ISEMBYLD approval and the resulting FDA issued label. We developed a rigorous program to study apitegromab, now known as ISEMBYLD in children and adults living with SMA. This program includes our global, randomized, double-blind, placebo-controlled Phase III SAPPHIRE study. In the positive SAPPHIRE study, we definitively demonstrated that in SMA patients on chronic background SMN2-targeted treatment, ISEMBYLD showed a gain in motor function while placebo was associated with a loss in motor function. The SAPPHIRE study also demonstrated that ISEMBYLD had a well-characterized safety profile. Turning now to the label, ISEMBYLD is indicated for the treatment of SMA in adult adults and children over 2 years who are currently receiving an SMN2-targeted treatment. The recommended dose is 10-milligram per kilogram IV, administered every 4 weeks. At this dose, ISEMBYLD led to a robust clinically meaningful improvement in most function. Specifically, compared to patients on an SMN2-targeted treatment alone, ISEMBYLD demonstrated a 2.2 point improvement at 1 year with a nominal p-value of 0.0121 as measured by the Gold standard Hammersmith Functional Motor scale. Importantly, 34.2% of patients receiving ISEMBYLD showed a 3-point or greater increase in the Hammersmith scale compared to 13.5% of patients on placebo at 1 year. ISEMBYLD treated patients with more than twice as likely as placebo-treated patients to demonstrate a clinically meaningful improvement 34.2% versus 13.5%. Indeed, they're almost 3x as likely as placebo-treated patients to reach this level of motor function improvement. To support the long-term safety, tolerability and clinical benefit of ISEMBYLD, a total of 246 SMA patients have been studied in our clinical program, and we have over 900 patient years of data. The safety and tolerability of ISEMBYLD in children and adults with SMA is highlighted in this table. Underscoring that safety profile, a total of 99% of patients from the Phase II TOPAS study at the Phase III SAPPHIRE study entered the Onyx long-term extension study and 93% of those participants currently remain in the study, some for more than 7 years. Taken together, these data demonstrate that ISEMBYLD, first and only muscle-targeted therapy for SMA can deliver compelling benefits for children and adults with this disease. The FDA approval of ISEMBYLD is an enormous milestone for the SMA community and for Scholar Rock. And before I hand the call over to Keith, I do want to take a moment to thank the patients families and the clinical colleagues around the world who support and commitment enabled ISEMBYLD to be developed. I'd also like to recognize the Scholar Rock of team, and in particular, my R&D colleagues and manufacturing colleagues to pursue a bold scientific vision with unwavering focus and determination, accomplishing something that has eluded the field for decades. My sincere congratulations to our team. At this point, I'll turn the call over to Keith to discuss our U.S. launch. Keith?

Thanks, Akshay. I am very pleased to report that we commenced the launch of ISEMBYLD immediately upon Friday's approval, we are thrilled to be serving the SMA community with this innovative first-ever muscle-targeted therapy and now defining a new standard of care for patients living with SMA. As I've shared with you in the past, the vast majority of patients continue to experience persistent and progressive muscle atrophy that limits both function and independence, despite receiving an SMN-targeted treatment. To this end, neurologists recognize that the future of treatment for patients with SMA is an approach that targets both the motor neuron and the muscle. Now with the FDA approval of ISEMBYLD, we are ushering in the next phase of innovation where neurologists can do just that. For patients receiving chronic SMN2-targeted treatment as demonstrated in the Phase III SAPPHIRE trial, ISEMBYLD can change the progression of SMA from a loss of motor function to a gain of motor function bringing life-transforming benefits to patients. Our Scholar Rock team is now executing on what we know well and what we do well. Our exceptionally talented and experienced field team is ready to deliver ISEMBYLD. Over these past months, the team has been hard at work, building and deepening relationships with the SMA community. Specifically, we continue to engage across the approximately 140 SMA treatment centers 200 prescribing physicians and their multidisciplinary care teams throughout the U.S. And now that ISEMBYLD is approved, we can execute on our plans, highlighting the compelling clinical benefits that ISEMBYLD can bring to the estimated 6,600 patients with SMA in the United States who are receiving an SMN2-targeted treatment. In terms of the launch, we expect a steady and consistent pace of ISEMBYLD patient starts as we work to serve a gradually increasing number of children and adults living with SMA. As we begin the launch of ISEMBYLD, establishing a seamless high-touch experience for patients and caregivers is a top priority. We have now launched our world-class patient support program, Scholar Rock Supports. The goal of this program is to provide robust dedicated long-term support for each and every patient and family throughout the ISEMBYLD treatment journey. Our Scholar Rock Supports program offers personalized comprehensive services to patients and caregivers, including disease and treatment education, insurance navigation infusion day logistics, caregiver support and financial assistance for eligible patients. We expect that approximately 50% of ISEMBYLD patients will be insured by government payers and the remainder to be covered by commercial payers, and we are working collaboratively with them to establish broad and reliable access to ISEMBYLD with coverage that is consistent with our label. I would now like to provide information regarding the price of ISEMBYLD. When establishing the price for ISEMBYLD, we considered several key factors, including the rarity of SMA the severity of SMA and the compelling clinical benefits of ISEMBYLD. First is the extreme rarity of SMA. As I mentioned earlier, there are only an estimated 6,600 patients in the United States who are receiving an SMN2-targeted treatment. Second is the severity of SMA, which is a devastating and progressive disease and despite the use of chronic SMN-targeted treatments over time, patients can plateau and decline leading to ongoing motor function loss. And lastly is the compelling clinical benefits that ISEMBYLD brings to patients, as demonstrated in the positive Phase III SAPPHIRE study, ISEMBYLD change the progression of SMA from a loss of motor function to a gain of motor function, specifically compared to patients on an SMN2 targeted treatment alone. ISEMBYLD demonstrated a greater than 2-point improvement in motor function at 1 year and we're nearly 3x as likely to reach a 3-point or greater increase in motor function. Based on the rarity and the severity of SMA and the compelling clinical benefits of ISEMBYLD, we expect the annual net cost in the U.S. for a typical patient to be approximately $310,000. This typical patient annual net cost takes into account the weight-based dosing in the ISEMBYLD label and the typical patient age and weight based on demographic data from Cure SMA, the single largest U.S. SMA registry. This typical annual net cost also takes into account expected compliance and mandatory government discounts. Of course, this annual net cost will vary based on the individual's weight and specific insurance coverage. The Wholesale Acquisition Cost, or WAC, of a single-use 150-milligram 3 ml vial is $11,659. While our team is in the field with health care providers, and Scholar Rock Supports is enrolling initial patients and caregivers. I'd like to provide an update on the commercial availability of ISEMBYLD. Vials have been on site at our third-party provider and are now being packaged and labeled ISEMBYLD will be available for infusion within days. Patients can receive their ISEMBYLD infusions at centers of excellence, freestanding infusion centers or in the patient's home through our home infusion network of more than 10,000 affiliated nurses nationwide. ISEMBYLD will be available through our specialty distributor and through our expanded specialty pharmacy network that is specifically designed to provide optionality for patients, caregivers, providers and payers. Importantly, patients can access ISEMBYLD through that same specialty pharmacy where they currently receive their SMN2-targeted treatment. In closing, we are very excited to be launching ISEMBYLD across the United States as we now begin to serve one patient, one caregiver and one family at a time. It is our ambition that every patient who can benefit from ISEMBYLD should have access to ISEMBYLD. And with that, I will turn it over to Vikas to provide a financial update.

Thank you, Keith. We are very proud of Friday's landmark approval of ISEMBYLD, and we are pleased that the U.S. launch is now underway. From a financial and operating perspective, we are in a very strong position. We exited June 2026 with $492 million in cash, cash equivalents and marketable securities. Looking forward, we have multiple nondilutive options available to us to continue to strengthen our balance sheet. First, with this approval, we now have an additional $150 million available to us under our debt facility. Second, we are very pleased to have received the priority review voucher from the FDA, which we intend to monetize. And third, as a commercial stage company, we will begin to recognize revenue from ISEMBYLD sales in the United States. We are well positioned to fund our ISEMBYLD launch in the U.S., our global expansion to reach patients in Europe, Japan and up to 50 countries around the world and advance our robust clinical pipeline and innovative platform. With this strong balance sheet, we do not intend to raise cash through an equity offering at this time. I would like to now provide additional details on the financials related to the U.S. launch of ISEMBYLD. As it relates to cost of goods, the current cost of inventory manufactured prior to FDA approval has already been expensed. For a period of time, cost of goods sold will primarily reflect expenses related to packaging, labeling and other overhead costs, and we then expect COGS to ramp up to a steady state over time beyond 2027. Turning to the inventory at distributors. While the first quarter of sales will reflect some level of inventory in the channel, we plan to keep levels at a minimum. We continue to operate with a tight financial plan and our prioritized investments remain focused on our ISEMBYLD launch in the U.S., launch readiness in Europe and Japan, strengthening our supply chain to support our expanding pipeline and our anticipated growing global commercial demand for ISEMBYLD over time and advancing our highly innovative clinical programs. With that, I would like to turn the call back to David. David?

Thanks, Vikas. Friday's FDA approval of ISEMBYLD, the world's first and only muscle-targeted therapy for children and adults with SMA is a defining moment for the SMA community. This achievement reflects years of rigorous science, disciplined execution, and the perseverance of a Scholar Rock team that never lost sight of the patients and families we aim to serve. I would like to express my gratitude to our team, our clinical investigators and our patient advocacy partners, including Cure SMA. Most importantly, I would like to thank the 246 patients and their families who participated in our SMA clinical trials. Their trust, dedication and determination made this milestone possible and continue to inspire our team as we begin to serve the SMA community with this important first-in-class muscle targeted therapy. We are incredibly proud of this milestone, but this is not the finish line. It is only the beginning. As we now enter the next phase of innovation for the SMA community, we do so with a bold ambition, to redefine what is possible for people living with SMA around the world beginning today with children and adults in the United States. With that, we'll now open the line for questions. Operator?

[Operator Instructions] Our first question coming from the line of Eric Schmidt with Cantor Fitzgerald.

Congrats on the landmark approval and the broad ISEMBYLD label. Maybe for Keith, can you provide a little bit more detail on some of the assumptions behind the average age, weight compliance and discounts that direct you to that $310,000 per year price point? And then a follow-up in terms of the ISEMBYLD label, obviously, the safety looks clean overall. But I'm hoping the team might address the language regarding fracture risk. Where is that coming from?

Thanks very much, Eric. We'll go to Keith first, and then Akshay will address the other item in the label regarding fractures. Keith?

Yes. Thanks, David. Eric, thanks for the question. I guess the first thing that I want to acknowledge is we're very gratified that the agency, the FDA recognized the important benefit that ISEMBYLD can bring to all adults and children 2 years of age and older with SMA, and that's reflected in this very broad label. As I mentioned in the prepared remarks, in any time we're go to price a drug, we always consider the extreme rarity and the severity, along with the compelling clinical benefit that ISEMBYLD demonstrated in our Phase III SAPPHIRE study. I mean I want to first remind you that the wholesale acquisition cost of a vial of ISEMBYLD is $11,659. Now as we took a look at the single largest SMA database that exists in the United States, the Cure SMA registry, we found that a typical patient is expected to weigh in the 35 to 45-kilogram range and would be infused with approximately 3 vials every 4 weeks. We've also assumed that a compliance rate of 85% to 90% being dosed every 4 weeks, you could have where patients will miss 1 to 2 doses per year. In addition, we factored in the mandatory government discounts I mentioned before that the payer mix is roughly 50% commercial and 50% government pay, but we also have patients that will be treated in 340B facilities. So when you factor in all of these things, compliance and the mandatory discounts, the typical patient weight of 35 to 45 kilograms, we're going to be at a net annual cost for a typical patient to be $310,000 and -- but I do want to close with reminding you that this price is going to vary on a patient-by-patient basis based on that patient's weight and their insurance coverage.

Thanks, Thanks, Keith. Akshay?

Yes. I appreciate the question on the safety, Eric. So a couple of things. First of all, we're very proud of our well-characterized safety profile for apitegromab based on several facts and 99% of patients from the Phase II and Phase III rolled into the Onyx long-term safety extension study. 93% of them are still on that study today, some out over 7 years, and all of that generated 900 patient years of safety data, which leads to the conclusion that the drug is well tolerated. As for the specifics of the frac question, the literature rates for annualized incidence rates for fracture in this patient population range from 4% to 14% and indeed, the cumulative lifetime prevalence is up to 40%. So our numbers are well within the annual incidence rate in actual fact. And I think we have to be mindful of the potential for the tyranny small numbers here with twice as many patients being on apitegromab in the Phase III as on placebo. And obviously, that can skew the amount of safety information you collect for both those groups. And just to illustrate the issue, no patients from the placebo arm who rolled on to active in the Onyx safety extension study had a fracture at year 1 versus if we look back at the SAPPHIRE Phase III study in eight patients on active had a factor at year 1. So the fact that the placebo patients going on to active drug apitegromab at 1 year having none shows you how these numbers can wobble around. And most important to me as a drug developer, I'd say when patients did have a fracture, number one, events were all classified as not related. So from their practice, the investigators appreciate background issues like osteoporosis and falls that were associated with the fracture events. They've seen them before many times. And b, all patients on study who had a fracture, stayed on drug and the factors resolved. Now I think that says something very important as well. And finally, I'll close by saying that not a single patient was withdrawn from drug after a fracture or came off study, and that's across the entirety of the clinical development program and the expanded access use program. So I think that's saying something very important as well, and we're very comfortable with the go-ahead safety profile. Thank you.

Our next question in queue coming from the line of Michael Yee with UBS.

Congrats on the approval. It's been a long time coming, and it's been a great journey. Two questions. One, just on thinking about the commercial launch. I know that you said you want to keep inventory low and some things like that. But can you just talk about what type of metrics? What type of data points you will provide? And what type of leading indicators you can be able to talk about over the first 1 or 2 quarters? And how we should be thinking about numbers of patients you think you can go after. I would think there's some bolus or other factors, but maybe you could talk about that over the next 1, 2, 3 quarters? And then just one detailed question about the fractures. I appreciate the comments you mentioned, but the label talks about specifically proximal type impact in mouse models. And so I just wanted to understand whether the fractures that you saw in the clinical data sets were proximal or distal and that might be helpful, too.

Thanks very much, Mike. We're going to go to Keith on the launch dynamics and metrics and then back to Akshay on the proximity, Keith?

Yes. Thanks, David. Mike, thanks for the question. As we've had additional time to prepare for this launch, we've really built one of the best in the industry, rare disease teams in several different aspects, whether it's the team that's out in the field or whether it's the business analytics team that's here in-house, I can tell you that internally, we already have scorecards that are ready to go, and we have a number of metrics that we will be looking at here internally. At this time, here we are on day 3. We haven't really made a decision on what type of metrics that we will commit to on earnings calls. Obviously, you know that we'll be reporting revenue, which will be the true north. It might not be the true north in quarter 1 because as you've heard me discuss before, that when a patient gets prescribed a brand-new therapy in rare disease, that usually leads to prior authorization and many times followed by a denial. So the revenue in quarter 1, I just want to say we'll have consistent and steady growth. Over time, we'll determine what other metrics that we will be bringing out obviously covered lives and how well we're doing on getting policies that are developed, which are in the public domain anyway. I think, will be a major factor as well as how well our coverage is doing for our team to where these 6,600 patients in the U.S. are currently being treated.

Thanks very much, Keith. Akshay?

Yes, Mike. So in terms of the animal data, the nonclinical profile. Obviously, those are very exaggerated doses and the proximal factors you mentioned in the clinical situation in the program, there are distal factors. And in fact, the range of fractures seen in the program is completely within the range that practice in the day-to-day in their practice with these patients. So as I said, 40% cumulative lifetime incidents of fractures, which is very sad for these patients. But of course, they have all these background concomitant factors like poor nutrition, osteoporosis, falls and hopefully, as the standards of care continue to improve, those will diminish. But the facts are distal so not related to the preclinical profile.

Yes, Mike, we saw your note from yesterday. And in fact, as you indicated as a question in Sapphire the three fever fractures were all distal.

[Operator Instructions] And our next question in the queue coming from the line of Kripa from Truist Securities.

Congratulations on the approval. I echo my long-term coming -- long time coming, but great journey. So I do just want to go back to the launch trajectory. When we think about it, what are the gating factors that we should be looking at? And in terms of payer coverage and formularies, how quickly do you expect top commercial health plans and the state Medicaid programs to establish formal policies. Are you expecting any kind of prior hurdles at all?

Thanks very much, Kripa, and it's been great to be on this journey with you. As I think Keith and I have noted with nearly all patients with SMA claiming that their #1 need is more motor function and more muscle strength. And 3/4 of neurologists indicating that the optimal way to treat patients with SMA is by both addressing motor neuron health as well as the muscle, the principal organ clinically affected in the disease. We certainly are expecting some nice demand features in the launch. But I think you adequately and appropriately focus a bit on the reimbursement and access side, which I think Keith has great confidence in over time, but those dynamics initially at launch, are worth him walking through. So I'll hand it over to Keith to comment on that. Keith?

Yes. Thanks, David. Kripa, I guess the first thing is, I agree with David. And I think we've shared that in the extra time that we've had and been able to be out there, it does seem like the demand to utilize apitegromab has grown from a physician and patient perspective. I think I just saw a survey that came out last week that showed 15 neurologists that were surveyed that 62% of them. They believe 62% of their current patients are good candidates for apitegromab and 3/4 of those physicians said that they could see themselves prescribing it within the first 3 to 6 months. So I do think that the demand is going to be there. With that being said, our market access team has already been meeting with not only the commercial payers but also government payers and working with Medicaid so that we could discuss what a potential policy could look like. And our goal is to have these policies that will be in line with the label. And as you know, we've got a very broad label here. So look forward to the ongoing discussions with the various payers, both private and public. With that being said, it typically takes a period of time for policies to get drafted and ultimately published. So what I do expect in this first 6 months that we will be without a [ J code ]. Now the good news is the timing of our approval. We are now only going to sit quarter 4 of this year and quarter 1 of next year with an unspecified [ J code ]. But with Scholar Rock Supports, we will be able to work through that period with an unspecified [ J code ]. But it will take time to get these policies up and in place. And I think the last thing I'll say is I've given you the statistic before, but in the last launch that I participated in, even 6 months post launch, the average time from prescription to actual infusion was still slightly over 60 days and that's where I'm going to ask that we'd be a little bit patient here in these first couple of quarters as the policies get published as the [ J code ] comes on board as hospital formularies put apitegromab on formulary and then you'll see that time shorten from prescription to infusion. Ideally, we'll get that down into the 10- to 14-day period.

Our Next question in queue coming from the line of Cory Kasimov with Evercore ISI.

Let me add my congrats on this approval. My question, I want to go back to the safety front and kind of a follow-up here by asking, did the FDA require any sort of post-marketing requirements or commitments specifically on whether it's bone or reproductive safety? Or is it sufficient that you kind of ongoing submit data from your ongoing open-label extension Onyx study on that front?

Yes, great question, Cory. Akshay?

Yes. And the answer is relatively straightforward. So there are no post-marketing safety commitments. With respect to the fractures on the reproductive side that you mentioned. And then there will be standard safety updates, but obviously, we'll be providing to the FDA.

Our next question in queue coming from the line of Geoff Meacham with Citi Group. Congrats on the approval.

This is Jarvey on for Geoff. Maybe just a quick question on the number of patients and percentage of them. Just can you give us a sense of what percentage of eligible patients reside at centers that are ready to prescribe and fuse ISEMBYLD immediately versus ones that center that maybe require a little bit more work and reach from your FTEs. And then maybe thinking about preparation, how are you preparing for demand is initial uptake exceeds expectations? Just given you mentioned that you guys plan on keeping inventory in the channels as low as possible.

Thanks, Jarvey. And as I think Keith and I have been noting for some time, a little bit of the extra time has been really helpful for Keith's team, which has really been able to work very closely with the SMA community, the centers of excellence, the KOLs also reach even deeper into the SMA community to understand care pathways and such. So Keith can comment on all of those questions. Keith?

Yes. Thanks a lot. I guess the first thing that I want to call out here that's a definite advantage for us in a rare disease launch is that these patients are known because as our label states, they are already on an SMN2-targeted therapy. So it's not about us being out there having to find the patients and have them diagnosed. They are already known. The second thing that I would say is the 6,600 patients that are on an SMN2-targeted therapy around the U.S. They really are predominantly in those either 140 centers or they're consulted by somebody at those SMA expert centers. But the 2,600 neurologists that currently prescribe for them is the group that we are actively covering. So I do feel good about the coverage that we're going to have in a timely manner because we have been establishing not just these relationships, but as David alluded to, it's even on a patient-by-patient basis on how they want us to participate enrolling that patient in Scholar Rock Supports will allow us to help with a number of different things, but that would also include infusion logistics, okay? Your second question is what if we get over demand into the system? I've got to tell you that I've got, I think, the best U.S. General Manager in the business in Rebecca McCloud. Rebecca also led the world-class [ Viv Gart ] launch with me at [ Argenics ] with my stay in [ Gravis ]. And as you know, our demand had increased greatly there. Now she's only even more experienced after having done this with CIDP and subcu. The team has already built contingency and backup plans in the event that we do have this demand will be able to cover it at Scholar Rock Supports, and we will be able to cover it at our external hub. So I really like the contingency plans that we've built, and I hope that we get to put them into action.

Our next question in queue coming from the line of Tessa Romero with JPMorgan.

Congratulations to you and the entire team at Scholar Rock and to patients and their families. Just to double click here on a prior question. As you think about ramp, is there a specific target or target you can tell us you would like to achieve, hopefully, on new patient starts, payer coverage as you move ahead, that may help guide us on how you're thinking about the trajectory here? And then I have a quick follow-up.

Okay. Thanks, Geoff. Keith?