Ultragenyx Pharmaceutical Q2 2025 Earnings Report

Ultragenyx Pharmaceutical EPS Results

• Actual EPS: -$1.17
• Consensus EPS: -$1.27
• Beat/Miss: Beat by +$0.10
• One Year Ago EPS: -$1.52

Ultragenyx Pharmaceutical Revenue Results

• Actual Revenue: $166.50 million
• Expected Revenue: $161.37 million
• Beat/Miss: Beat by +$5.13 million
• YoY Revenue Growth: +13.20%

Ultragenyx Pharmaceutical Announcement Details

• Quarter: Q2 2025
• Date: 8/5/2025
• Time: After Market Closes
• Conference Call Date: Tuesday, August 5, 2025
• Conference Call Time: 5:00PM ET

Ultragenyx Pharmaceutical (NASDAQ:RARE), a biopharmaceutical company, focuses on the identification, acquisition, development, and commercialization of novel products for the treatment of rare and ultra-rare genetic diseases in North America, Latin America, Japan, Europe, and internationally. Its biologic products include Crysvita (burosumab), an antibody targeting fibroblast growth factor 23 for the treatment of X-linked hypophosphatemia, as well as tumor-induced osteomalacia; Mepsevii, an enzyme replacement therapy for the treatment of children and adults with Mucopolysaccharidosis VII; Dojolvi for treating long-chain fatty acid oxidation disorders; and Evkeeza (evinacumab) for the treatment of homozygous familial hypercholesterolemia. The company's products candidatures include DTX401, an adeno-associated virus 8 (AAV8) gene therapy clinical candidate for the treatment of patients with glycogen storage disease type Ia; DTX301, an AAV8 gene therapy for the treatment of patients with ornithine transcarbamylase; UX143, a human monoclonal antibody for the treatment of osteogenesis imperfecta; GTX-102, an antisense oligonucleotide for the treatment of Angelman syndrome; UX111, an AAV9 gene therapy product candidate for the treatment of patients with Sanfilippo syndrome type A, or MPS IIIA, a rare lysosomal storage disease; UX701, for the treatment of Wilson disease; and UX053 for the treatment of glycogen storage disease type III. Ultragenyx Pharmaceutical Inc. has collaboration and license agreement with Kyowa Kirin Co., Ltd.; Saint Louis University; Baylor Research Institute; REGENXBIO Inc.; Bayer Healthcare LLC; GeneTx; Mereo; University of Pennsylvania; Arcturus Therapeutics Holdings Inc.; Solid Biosciences Inc.; Regeneron; Abeona; and Daiichi Sankyo Co., Ltd. The company was incorporated in 2010 and is headquartered in Novato, California.

Ultragenyx Pharmaceutical Q2 2025 Earnings Call Transcript

Key Takeaways

• Positive Sentiment: Ultragenyx expects to unblind final Phase III ORBIT and COSMIC data for UX143 (cetrusumab) around year-end after a Data Monitoring Committee recommended continuing to final analysis, reinforcing confidence in its potential to strengthen bones and reduce fractures in osteogenesis imperfecta patients.
• Positive Sentiment: GTX102 for Angelman syndrome received Breakthrough Therapy Designation in June and completed Phase III ASPIRE enrollment of 129 patients ahead of plan, with a readout expected in 2026 and a supportive AURORA study to begin enrolling later this year.
• Positive Sentiment: Second-quarter revenue reached $166 million, up 20% year-over-year, driven by Crysvita, Dajolvi, Akilassa, and Mepsevii, and management reaffirmed full-year guidance of $640 million to $670 million in total revenue.
• Negative Sentiment: UX111 for MPS IIIA received a Complete Response Letter prompting Ultragenyx to address CMC and updated clinical data through a Type A meeting before resubmitting its BLA, which may add up to a six-month review delay.
• Positive Sentiment: DTX401 for glycogen storage disease type 1a is on track for a fourth-quarter BLA submission with proactive CMC preparations to minimize regulatory review risks.

Presentation

[Operator]

Good afternoon, and welcome to the Ultragenyx Second Quarter twenty twenty five Financial Results Conference Call. At this time, all participants are in a listen only mode. At the end of the prepared remarks, you will have an opportunity to ask questions during the Q and A portion of the call. It is now my pleasure to turn the call to Joshua Higa, Vice President of Investor Relations.

[Joshua Higa, VP - IR at Ultragenyx Pharmaceutical]

Thank you. We have issued a press release detailing our financial results, which you can find on our website at ultragenyx.com. Joining me on this call are Emil Kakus, Chief Executive Officer and President Eric Harris, Chief Commercial Officer Howard Horn, Chief Financial Officer and Eric Crombez, Chief Medical Officer. I'd like to remind everyone that during today's call, we will be making forward looking statements. These statements are subject to certain risks and uncertainties and our actual results may differ materially.

[Joshua Higa, VP - IR at Ultragenyx Pharmaceutical]

Please refer to the risk factors discussed in our latest SEC filings. I'll now turn the call over to Emil.

[Emil Kakkis, Founder, President & CEO at Ultragenyx Pharmaceutical]

Thanks, Josh, and good afternoon, everyone. In April 2025, we marked our fifteen year anniversary as a company. Over that time, we've taken four programs all the way through approval in multiple regions and added a fifth that we are commercializing outside of The U.

[Emil Kakkis, Founder, President & CEO at Ultragenyx Pharmaceutical]

S. At the same time, we've also refilled the clinical pipeline, now have five Phase III clinical programs fully enrolled or at the BLA submission stage. And over the last fifteen years, Ultragenyx has been the most productive rare disease company in the industry across a broad range of modalities and therapeutic areas. Through the 2025, we continue this momentum with meaningful progress across our larger programs. I'll begin with UX143, cetrusumab for our fully human monoclonal antibody for the treatment of osteogenesis imperfecta.

[Emil Kakkis, Founder, President & CEO at Ultragenyx Pharmaceutical]

The ORBIT and COSMIC studies are continuing to the final analysis that will occur around the end of the year. While we hope the studies might have stopped early at the interim time point last month, we remain confident in completing a successful study. We're pleased the safety profile is as expected and that after looking at the day the DMC recommend we continue to the final analysis. As we head to the final analysis, the continued treatment of Phase III should further strengthen bones of the treated patients. The additional six months of treatment for the treated subjects along with the larger p value threshold of 0.04 will help power the final assessment.

[Emil Kakkis, Founder, President & CEO at Ultragenyx Pharmaceutical]

We look forward to unblinding the Phase III data sets and sharing results around the end of the year. Now based on all the data we've seen in Phase II, we're confident UX-one hundred forty three will be a transformational treatment for pediatric and adult patients with osteogenesis imperfecta. The combination mechanism of building bone and reducing excess resorption is exact at exactly the sites in their body where they need more bone will increase bone strength and reduce fractures while at the same time improving overall bone health. In addition to reducing fractures, we're encouraged by the functional effect we're seeing on increasing physical activity ability that speaks to long term potential for this treatment. Now shifting now to GTX-one hundred two, our antisense oligonucleotide or ASO for the treatment of Angelman syndrome.

[Emil Kakkis, Founder, President & CEO at Ultragenyx Pharmaceutical]

GTX-one hundred two received breakthrough therapy designation from the FDA in June. BTD aims to exercise development review of drugs that are intended to treat serious or life threatening diseases and whose preliminary clinical evidence indicates the drug may demonstrate substantial improvement over existing therapies. Historically, seems like there have been relatively few breakthrough therapy designations granted in the field of neurology because it can be challenging to demonstrate a meaningful clinical effect on neurologic disease symptoms, but for GTX-one hundred two we have been able to do that. The BTD designation was obtained based on our Phase onetwo study data in seventy four patients with a full maternal UB3A deletion that showed consistent developmental gains with rapid sustained and continued improvements across multiple symptom domains when patients have been on therapy for up to three years. For GTX-one hundred two, the magnitude and durability of our Phase onetwo data indicate our ASO is meaningfully improving lives of patients who have this neurodevelopmental disorder.

[Emil Kakkis, Founder, President & CEO at Ultragenyx Pharmaceutical]

Last week, we also announced that GTX-one 102 Phase three study ASPIRE completed enrollment ahead of plan with 129 patients in seven months. The interest from investigators and patients helped drive the rapid enrollment, but I also applaud our team for their efforts to expeditiously enroll this study. We're thankful for the support from the patient communities and investigators who helped us exceed our expectations. We're now on track to read out Phase III data from this forty eight week study in the 2026. Now switching to our commercial progress for the 2025.

[Emil Kakkis, Founder, President & CEO at Ultragenyx Pharmaceutical]

Our commercial teams continue their trend of delivering double digit revenue growth. The $3.00 $6,000,000 of total revenue across the first two quarters represents 20% growth versus the prior year and keep us on track to deliver $640,000,000 to $670,000,000 of total revenue this year. Crysvita is continuing to grow in line with our expectations from royalty revenue U. S. And Canada and product revenue in Latin America and Turkey.

[Emil Kakkis, Founder, President & CEO at Ultragenyx Pharmaceutical]

Doljovi, AvKissa and Mefcevi also continue to contribute to our top line as each of these launches are progressing well. I'll now hand it off to our Chief Commercial Officer, Eric Harris to give us some additional details on his team's recent performance.

[Erik Harris, EVP & CCO at Ultragenyx Pharmaceutical]

Thank you, Emil, good afternoon everyone. As Emil mentioned, my team is continuing to successfully commercialize four products across the globe. Starting with Crysvita in Latin America, in the second quarter, our team generated approximately 50 new start forms that led to approximately 50 patients on reimbursed therapy. We now have approximately eight twenty five patients on commercial product in the region as the team continues to exceed our expectations for Crysvita. We continue to receive positive feedback from healthcare providers in the region, who tell us how much better their patients feel when on Crysvita, which has led to an increasing number of doctors writing prescriptions for multiple patients.

[Erik Harris, EVP & CCO at Ultragenyx Pharmaceutical]

We expect growth in the region to continue following the successful negotiation of reimbursement from the Brazilian and Mexican authorities, the two largest payers in the region and continued expansion in other Central and South American countries. I'll now shift to Crysvita in The United States and Canada, where our partner, Keyaur Kirin, has been leading commercialization for Crysvita since the transition in April 2023. Revenue in the second quarter twenty twenty five was supported by increasing new start forms and new patients on reimbursed therapy. We expect 2025 U. S.

[Erik Harris, EVP & CCO at Ultragenyx Pharmaceutical]

And Canada Crysvita revenue to continue growing as they work to identify new pediatric and adult patients with XLH and convert them to treatment. Moving on to DERJOVY in The United States, growth of new start forms in the second quarter continued to steadily increase consistent with the patterns we have seen in prior quarters. Our team generated approximately 30 new start forms and added approximately 30 new patients to reimburse therapy. This brings the total since launch in 2020 to approximately 600 patients on reimbursed therapy. The split between pediatric and adult patients continues to be approximately 65% peds and 35% adults.

[Erik Harris, EVP & CCO at Ultragenyx Pharmaceutical]

The total number of prescribers also continues to grow with a total of approximately two seventy unique prescribers at the end of the second quarter. For DERJOVY across the EMEA region, there are approximately two eighty patients treated under named patient sales across the region. The majority of demand is from France, but we are continuous but we are seeing continuous growth across the EMEA region, including Kuwait, Saudi Arabia and Greece. The demand for this product is quite strong across this region, especially given the fact that we are not actively marketing the therapy and simply responding to named patient requests. Before I close, I'll make a few comments on Efkesa, which we began commercializing in territories outside The U.

[Erik Harris, EVP & CCO at Ultragenyx Pharmaceutical]

S. With formal reimbursement approvals in just the last couple of years. In the EMEA region, we now have patients on reimbursed therapy from nearly all of the major countries and we have added almost 100 patients since the beginning of the year with a total of approximately two eighty five patients across 15 countries. We continue to successfully navigate the country by country pricing negotiations and respond to named patient treatment requests across the whole EMEA region. Our team in Japan continues to build on the launch momentum following the pricing and reimbursement approval that we received last year.

[Erik Harris, EVP & CCO at Ultragenyx Pharmaceutical]

In Canada, we are continuing pricing negotiations with government health authorities and recently added younger pediatric patients to the label. Over time, we expect AFKEASA revenue to contribute more meaningfully to the total revenue as we continue to successfully launch this transformative product for HoFH patients with its high potency due to a novel mechanism of action regardless of background therapy. As I have mentioned on previous earnings calls, we continue to expect some quarter to quarter variability in revenue, primarily due to uneven ordering patterns for Crysvita in Latin America. But we remain confident in the growing underlying demand for all of our products around the world. With that, I'll turn the call to Howard to share more details on our financial results and guidance.

[Howard Horn, CFO & EVP - Corporate Strategy at Ultragenyx Pharmaceutical]

Thanks, Eric, and good afternoon, everyone. I'll focus on second quarter twenty twenty five financial results and guidance for the year. Starting with total revenue. In the 2025, we reported $166,000,000 representing 13% growth over the 2024 and twenty percent growth for the 2025 over the 2024. Crysvita contributed $120,000,000 in the second quarter, including $79,000,000 from North America, 35,000,000 from Latin America and Turkey and $7,000,000 from Europe.

[Howard Horn, CFO & EVP - Corporate Strategy at Ultragenyx Pharmaceutical]

Dejolvi contributed $23,000,000 consistent with its expected steady growth trajectory. AKIZA contributed $15,000,000 as demand continues to build following launches in our territories outside of The United States. And Mepsevii contributed $8,000,000 as we continue to treat patients in this ultra rare indication. Total operating expenses for the quarter were $274,000,000 which included R and D expenses of $165,000,000 SG and A expenses of $87,000,000 and cost of sales of $23,000,000 Operating expenses included non cash stock based compensation of $39,000,000 For the quarter, net loss was $115,000,000 or $1.17 per share. As of June 30, we had $539,000,000 in cash, cash equivalents and marketable securities, which included $80,000,000 of net proceeds raised through our ATM facility.

[Howard Horn, CFO & EVP - Corporate Strategy at Ultragenyx Pharmaceutical]

For the three months ended 06/30/2025, net cash used in operations was $108,000,000 and in total for the six months ended 06/30/2025, it was $275,000,000 We now expect 2025 net cash used in operations to modestly increase compared to 2024, primarily driven by timing delays associated with UX-one 111, DTX-four zero one and UX-one 143. We will remain on our path or excuse me, we remain on our path to GAAP profitability in 2027 and we'll continue to focus on growing revenues and rigorously prioritizing our spend, including stopping and delaying certain expenses prior to upcoming potential commercial launches. Shifting to revenue guidance for 2025, we are reaffirming the guidance we provided in February and May. Total revenue is expected to be between $640,000,000 and $670,000,000 which represents 14% to 20% growth over 2024. Crysvita revenue is expected to be between $460,000,000 and $480,000,000 which includes all regions and all forms of Crysvita revenue to Ultragenyx.

[Howard Horn, CFO & EVP - Corporate Strategy at Ultragenyx Pharmaceutical]

This range represents 12% to 17% growth over 2024. Dajolvi revenue is expected to be between 90,000,100 million dollars which represents 2% to 14% growth over 2024. With that, I'll turn the call to our CMO, Eric Crombez, who will provide operational updates on the clinical programs.

[Eric Crombez, EVP & Chief Medical Officer at Ultragenyx Pharmaceutical]

Thank you, Howard, and good afternoon, everyone. I'll start with GTX-one2 for the treatment of Angelman syndrome. As Emil mentioned, we completed enrollment in the Phase III ASPIRE study ahead of initial expectations. Enrolling 129 patients across six countries in a randomized controlled study in seven months is a remarkable accomplishment. This would not have been possible without the incredible dedication and support from the Angelman community, study site teams and investigators.

[Eric Crombez, EVP & Chief Medical Officer at Ultragenyx Pharmaceutical]

The accelerated enrollment of the Phase III study underscores the urgent need and strong desire for an effective treatment for these patients. We will now shift our enrollment efforts to the AURORA study that will target younger and older patients and those with other genotypes. This study is open label and intended to provide supportive information on safety and efficacy supportive The protocol has been finalized, and we expect to begin enrollment in the second half of this year. Data from this ongoing study will be included in approval filings after successful completion of the Phase III ASPIRE study. Shifting to UX-one 111 for the treatment of MPS IIIA or Sanfilippo syndrome type A.

[Eric Crombez, EVP & Chief Medical Officer at Ultragenyx Pharmaceutical]

We received a complete response letter for our BLA filing last month, and we are actively working with the FDA to resolve the observations through a plan Type A meeting that should lead to an understanding of what is required for refiling of the BLA. Once resolution has been achieved, we expect to resubmit the BLA and anticipate an up to six month review. I think it's important to note that the clinical review had been ongoing and that the FDA acknowledged at the late cycle review meeting that the neurodevelopmental outcome data is robust and that the biomarker data provided additional supportive evidence. The CRL did not note any review issues related package nor comment on the clinical inspection. There is a request for updated clinical data for specific clinical and biomarker endpoints and safety to be included in the resubmission.

[Eric Crombez, EVP & Chief Medical Officer at Ultragenyx Pharmaceutical]

Next, DTX401 for the treatment of glycogen storage disease Type 1a, where we are now on track to submit a BLA in the fourth quarter of this year. We have been working on the BLA over the last couple of quarters and the nonclinical and clinical sections are ready to submit. We want to proactively resolve any relevant CMC and facility questions that derive from the UX-one 111 CRL that could possibly impact the DTX401 submission before we finalize the CMC section of the BLA. We expect to resolve the observations over the next few months and then finalize the BLA submission. Finally, UX701 for the treatment of Wilson disease.

[Eric Crombez, EVP & Chief Medical Officer at Ultragenyx Pharmaceutical]

Recall, we are in the dose finding stage of the study and in Cohort four, we are evaluating a dose of 4e13. All patients in this cohort will receive immunomodulation therapy with rituximab and tacrolimus in addition to the prophylactic oral corticosteroid regimen patients in cohorts one through three received. Enrollment and dosing in cohort four is underway and we expect to complete enrollment in the next month or two. I'll now turn the call back to Emil to provide some closing remarks.

[Emil Kakkis, Founder, President & CEO at Ultragenyx Pharmaceutical]

Thank you, Eric. I'll quickly recap the milestones and catalysts over the second half of the year. For UX-one hundred forty three and Osteogenesis Imperfecta, we expect to have top line data from the final analysis of the Orbit and COSMIC studies around the end of the year. For GTX-one hundred two and Angelman syndrome, we'll continue treating patients in the forty eight week ASPIRE study and we'll begin enrollment in support of AURORA study in the 2025. For UX701 in Wilson, we'll complete enrollment of the fourth cohort in the next couple of months.

[Emil Kakkis, Founder, President & CEO at Ultragenyx Pharmaceutical]

We expect to make a determination on the stage two dose in 2026. For UX111 in Sanfilippo syndrome, are working toward a Type A meeting with the FDA to get agreement on our plan to resolve their observations, which we believe we can address. Following this, we would work through agreements to resubmit the BLA, which we followed by a review period that could take up to six months. Lastly, for DTX401 and GC1a, the BLA submission is on track and should be submitted in the fourth quarter. These last fifteen years at Ultragenyx have been incredibly fulfilling and yet the best is still to come.

[Emil Kakkis, Founder, President & CEO at Ultragenyx Pharmaceutical]

While the news last month did delay our approval for UX-one 111 and didn't accelerate the OI program, we're confident in the strong portfolio we have to build our future. Over the next six months, we expect to continue growing revenue, tightly manage expense and cash burn while we maintain our path to profitability in 2027. With that, let's move on to your questions. Operator, please provide the Q and A instructions.

[Operator]

Thank you. We will now be conducting a question and answer session. Our first question comes from the line of Joseph Schwartz with Leerink Partners. Please proceed with your question.

[Will Soghikian, VP - Equity Research at Leerink Partners]

Hey guys, this is Will on for Joe. Thanks for taking our questions today. Congrats on the progress this quarter. So one for us, considering the leadership at the agency has been rather fluid lately, could you provide a glimpse into any of your recent FDA interactions, especially at CBER? Are you noticing any meaningful changes in messaging and or the folks that you're interacting with?

[Will Soghikian, VP - Equity Research at Leerink Partners]

Just trying to get a sense for how impactful these headlines we've all been seeing are on a day to day interaction basis for Ultragenyx? Thank you.

[Emil Kakkis, Founder, President & CEO at Ultragenyx Pharmaceutical]

Well, think our interactions since the CRL of late has been good. I think they are productive and we're working toward getting our Type A meeting package sent in. So we're pleased with how things are going. I know they've under a lot of duress at the agency, lot of turmoil and change, but things have been going well. We're pleased with the progress so far.

[Will Soghikian, VP - Equity Research at Leerink Partners]

Great. Thank you.

[Operator]

Thank you. Our next question comes from the line of Jun Li with Truist Securities. Please proceed with your question.

[Mehdi Goudarzi, Biotech Equity Research Analyst at Truist Securities]

Hi. Thanks for taking our question. This is Mehdi on for Jun. Given GTX-one hundred two and rubeoneersen both use LNA chemistry, could you please elaborate on non target site dependent factors that drive very different dosing regimens that you both have for these drugs?

[Emil Kakkis, Founder, President & CEO at Ultragenyx Pharmaceutical]

Well, the LNA chemistry we're using is primarily chosen because it is substantially more potent. It can have more toxicities and which is known, but its potency is was dramatically better for the target on the or at least one or a magnitude or more in our hands when we compare it to non LNA chemistry. So there's a reason for it. We think the potency gives us a dosing that's in the five milligram to fourteen milligram range, which I think is a distinct advantage because the non chemical or the chemical based off target effects will be less since we're operating at a relatively low chemical concentration. It's a little hard to compare all the different molecules, arugeneris and the one from Roche is also in LNA, the one from Ionis is a different chemistry.

[Emil Kakkis, Founder, President & CEO at Ultragenyx Pharmaceutical]

Each of the chemistries has upsides and downsides. We believe the LNA strategy in this case for this target gives us a much better potency and a better therapeutic window. I think that's why I think we're seeing, we think better results in our program so far and why we've been given breakthrough therapy designation based on FDA's review of our data.

[Mehdi Goudarzi, Biotech Equity Research Analyst at Truist Securities]

Thank you.

[Operator]

Thank you. Our next question comes from the line of Gena Wang with Barclays. Please proceed with your question.

[Gena Wang, MD - Biotech Equity Research at Barclays]

Thank you. I have a two stats question. The first one is regarding COSMIC trial. Ami, maybe can you remind us, what's the reason to run COSMIC trial? And then what is your assumption for bisphosphonate arm?

[Gena Wang, MD - Biotech Equity Research at Barclays]

And if trial fail, but Orbit is positive, how do you see the payer and the physician uptake of the drug? My second question, if I may, just also very quick stats question regarding Phase III ASPIRE. Your secondary endpoint, you allocate 10% of alpha. Just want to confirm, is that the 0.005? And why isn't it statistic hierarchy to have a full 0.05 alpha LOT for the secondary endpoint?

[Emil Kakkis, Founder, President & CEO at Ultragenyx Pharmaceutical]

Thank you. Of course, you and I would not expect anything more than detailed statistical questions. So thank you for that diving deep. So the COSIC study and the reason for it is to look at young patients who have severe disease who couldn't go in a placebo controlled trial. And in this case, they'd want to be on the drug that they're on, which they're on bisphosphonates.

[Emil Kakkis, Founder, President & CEO at Ultragenyx Pharmaceutical]

So they all have been on bisphosphonates. We're simply randomizing some to go on our drug versus stay on bisphosphonates. We didn't assume a change in the fracture rate for those patients with phosphomy, we assume that they continue to sustain. The question is can we get a fifty percent improvement, which is what we were trying to power for. The one advantage of the study, although you would say a head to head may have less power, but I'd also argue that the population is very narrow.

[Emil Kakkis, Founder, President & CEO at Ultragenyx Pharmaceutical]

They're all very young patients that have a very rapid response to the drug, a very rapid bone mineral density production response to the drug. And we think that that will help power the results. So if for example, we believe the study has the power to succeed. If it perhaps just missed for example showed a difference, think it still would provide supportive data in the age group and supportive data what the head to head looks like. I actually think the study should hit though because I think of the consistent responsiveness of patients of that age and the fact that bisphosphonates have a relatively weak and variable bisphosphonates response, we feel good about the fact that the combination mechanism of action of our drug will overcome whatever you might see with bisphosphonates.

[Emil Kakkis, Founder, President & CEO at Ultragenyx Pharmaceutical]

And our read so far is that we're not worried about bisphosphonates as a competitor, but we want to have the data to prove to authorities, right, cetirizimab is superior to bisphosphonates. With regard to Aspire, Aspire we put we allocated the primary to 90% of the power is to the Bailey and 10% is to the MDRI, which we call it key secondary, but it's really the primary alpha split. The reason for that is the MDRI is a very powerful method which we see very strong statistical significance. So we didn't need to use much power to do that. But the idea was if MDI hits, it gives us a way of having a successful study no matter what happens to Bayley.

[Emil Kakkis, Founder, President & CEO at Ultragenyx Pharmaceutical]

If Bayley hits, we expect both to hit, then it's fine. Could be done sequential, you could do a sequential Bailey first then MDI or MDI first then Bailey and kept all 0.05. But by doing them separately, means that we're not dependent on Bayley. It doesn't have to hit in order to succeed in this design. We could still have a successful trial even if Bayley were not to hit.

[Emil Kakkis, Founder, President & CEO at Ultragenyx Pharmaceutical]

I think it just provides a more secure approach to statistics here. And but we appreciate sequential would be another way to do it, but we think what we've picked gives us the best chance and brings forth a new method. The MRI method is a new method for FDA, but it is a powerful method and we think will become the dominant superior way to look at complex multi domain neurologic development disorders. And once we start showing this in this study, I think people will understand how much more powerful it is when you're talking about a very heterogeneous population of patients. So we're excited that the FDA has given us a chance to put that forth as one of the primary ways to assess our Phase III study.

[Operator]

Thank you. Our next question comes from the line of Tazeen Ahmad with Bank of America. Please proceed with your question.

[Tazeen Ahmad, MD - US Equity Research at Bank of America]

Hi, good evening. Thanks for taking my question. Amos, for the third and final read for Or Orbit, there is some debate among investors that if it is statistically significant at that final read at eighteen months that the level of clinical benefit will also matter more than it might have at twelve months because the argument is if it's taking that long to separate from bisphosphonates, how much better is it than bisphosphonates. So I wanted to get your thoughts on what you think doctors would think about that particular argument. Does it matter the as long as it's statistically significant, does it matter how much separation it's getting at the eighteen month time point? Thanks.

[Emil Kakkis, Founder, President & CEO at Ultragenyx Pharmaceutical]

Thanks Tizine. I think if you look at the treatment effect estimate, the difference between patients, I think you could have the same difference. But because of more variation, it just might make more take longer to separate the groups. But the treatment effect size could very well be the same. We had to try to caution people that if it's 60%, 67%, 40%, 50% in this range, it is substantially better than what's certainly observed.

[Emil Kakkis, Founder, President & CEO at Ultragenyx Pharmaceutical]

And I don't think that that percent number is going to have a dramatic impact exactly on what happens. I think any number in that range is a strong benefit to patients. What we can see from Phase II though is that the effect on functional ability and other aspects of the patient health is substantial and really that is what's going to drive the benefit. To give you the parallel to the I always talk about XLH, the Crysvita story, we had an RSS score, was a primary endpoint, but there's no patient looking at the RSS score change percent telling us whether they're going to put the kid on drug or not. The truth is that proves that it does improve rickets, but the reason it has so successful is patients feel great, are more functional, more active, just like we're seeing with OI.

[Emil Kakkis, Founder, President & CEO at Ultragenyx Pharmaceutical]

That's what drives prescriptions. That's what drives patient demand. The numbers we have to hit, we will hit the numbers. I think the thing in utilization will come from the overall benefit. And we think what we're seeing in Phase II makes this drug at least as good as Crysvita and its effect on OI.

[Emil Kakkis, Founder, President & CEO at Ultragenyx Pharmaceutical]

So that's why we're confident about where it goes. Thanks, operator. Let's move to

[Emil Kakkis, Founder, President & CEO at Ultragenyx Pharmaceutical]

Thank the next you.

[Operator]

Our next question comes from the line of Narayama with JPMorgan. Please proceed with your question.

[Analyst]

Hey guys, this is Billy on for Anupam. Thanks for taking our question. Just while I appreciate the FDA acknowledged the neurodevelopmental outcomes data are robust and the biomarker data are supportive evidence. What additional clinical data is likely to be included in resubmission? Is this more kind of longer duration data we're thinking or additional biomarkers that would be asked for? Thanks.

[Emil Kakkis, Founder, President & CEO at Ultragenyx Pharmaceutical]

Yes. So what they specifically asked for was an update on the clinical endpoint data and the biomarker data just because time will have passed, they just wanted the latest data we had, which we have data patients have been ongoing in the study. So we'll collect their Bayley data and their Vineland data, the data that sort of the developmental data they've seen, which they considered robust. And we'll include whatever CSF biomarker data we have as well in that assessment as requested. So it's pretty much an update on the ongoing data and it was more because time had passed, they just want to see everything continue as we believe.

[Emil Kakkis, Founder, President & CEO at Ultragenyx Pharmaceutical]

And we believe patients are doing well and it will be what I would call a routine update of the clinical data.

[Analyst]

Thank you.

[Operator]

Thank you. Our next question comes from the line of Kristen Kluska with Cantor Fitzgerald. Please proceed with your question.

[Kristen Kluska, Equity Research Analyst at Cantor Fitzgerald]

Hi, good afternoon everybody. For the Orbit study reading out later this year, I know you still have very high conviction in the trial being successful, but I wanted to talk about a hypothetical scenario where maybe the fracture data falls slightly under what you were hoping for, but you see really strong benefits on pain. Do you still think that there's a strong case to make for the FDA here? And could you argue that this will drive higher adoption for patients since they deal with this on a daily basis over the fracture aspects?

[Emil Kakkis, Founder, President & CEO at Ultragenyx Pharmaceutical]

Well, I think that your point is maybe there's a lot of some variation in fractures and you just missed that and you have other supportive data. I think data the FDA will always look at the totality of the data in a rare disease program. We've had that many times in many programs. Our sense here is that we're seeing a fundamental mechanistic effect on bone mineral density. The effect it has on fractures depends on how many fractures that patient have their particular condition.

[Emil Kakkis, Founder, President & CEO at Ultragenyx Pharmaceutical]

We have a lot more type 3s and type 4s in the study. They have a lot of complex problems. And so I'm sure that the support of other data would help us in any situation, whatever the statistical or treatment size is. And so that's just generally been the case. We feel confident the fracture data will be what it is.

[Emil Kakkis, Founder, President & CEO at Ultragenyx Pharmaceutical]

We're seeing what's going on in Phase II. We know that as time goes on there's very few fractures among patients after they've gotten established on the treatment. So we feel good we'll be able to do that. But hypothetically, I think the data will always be more than just fractures in this disease state. And the body of data we have, we think will support its use however we come out with on fractures.

[Operator]

Thank you. Our next question comes from the line of Yigal Nochomovitz with Citigroup. Please proceed with your question.

[Yigal Nochomovitz, Director at Citigroup]

Hey, thank you. Hi, Emil and team. I just had a clarifying question firstly regarding GSD1a in the filing. I think Eric you mentioned that you were making sure that you wanted to resolve any of the outstanding CMC issues on 01/2011 before submitting GSD1a. Could you just clarify, is there a specific question that you're trying to answer on CMC related to GSD1a by virtue of clarifying something on UX 111?

[Yigal Nochomovitz, Director at Citigroup]

Or is this simply just a matter of taking extra precaution to make sure that you've got everything right before filing the GSD1a BLA?

[Emil Kakkis, Founder, President & CEO at Ultragenyx Pharmaceutical]

Eric, did you want to answer that? Or you'd like me to answer that?

[Eric Crombez, EVP & Chief Medical Officer at Ultragenyx Pharmaceutical]

I'll give it a shot and certainly happy for the follow-up. But it's important to remember that the manufacturing facility up in Bedford is producing the gene therapy for MPS IIIA as well as for GSD1a. Any findings related to that manufacturing facility would potentially pull through to GSD1a. So we just want to make sure we work through all of that, and any pull throughs to GSD1a.

[Yigal Nochomovitz, Director at Citigroup]

Okay, thanks. Then on OI, Can you hear me?

[Eric Crombez, EVP & Chief Medical Officer at Ultragenyx Pharmaceutical]

Yes, no, I think we're good. Go ahead.

[Yigal Nochomovitz, Director at Citigroup]

Okay. I was going to say on OI, given the first two interims have passed and now we're looking at the final one. I'm just curious if you have any updated thoughts as far as what you believe the expected placebo AFR would be. Obviously, we've done some work and there are number of epidemiologic studies out there both in Scandinavia as well as The United States, which point to various ranges for AFR. I'm just wondering if you could comment on what you believe would be the most likely scenario at this point as well as on some of the more specific aspects of the statistics again regarding this concept of variance or over dispersion, which as we know is a feature of this particular dataset given the way the fractures are distributed? Thank you.

[Eric Crombez, EVP & Chief Medical Officer at Ultragenyx Pharmaceutical]

Yes. So yes, we're aware of the annualized fracture rate available in literature and looking at natural history, the principal investigators have on hand. We really use, a lot of the data coming on for pretreatment for baseline for both Orbit and COSMIC to do our modeling. And we were really looking at those patients with a baseline AFR between 0.721 for our modeling to support both of the work for interim analysis and obviously the powering we did for the primary efficacy analysis period at eighteen months. And with the dispersion, yes, I mean, I think, while we did not change entry criteria for ORBIT Phase II going into ORBIT Phase III, On the strength of the Phase two data, we had really what I consider to be a self enrichment of patients with Type 3s and Type four.

[Eric Crombez, EVP & Chief Medical Officer at Ultragenyx Pharmaceutical]

I think they needed to see that strong safety and efficacy data to take the risk to come into clinic because remember, really are at risk just from traveling into sites to sign consents and begin studying participation. So I will say, we did we have a greater number of patients with Type three and Type four OI in the Phase three part of ORBIT compared to Phase two.

[Yigal Nochomovitz, Director at Citigroup]

Okay. Thank you.

[Operator]

Thank you. Our next question comes from the line of Salveen Richter with Goldman Sachs. Please proceed with your question.

[Tommie Reerink, Biotech Equity Research Associate at Goldman Sachs]

Hi, thanks for taking our question. This is Tommy on for Salveen. How are you thinking about the bar for the Angelman data next year, both from a regulatory and competitive standpoint? And wondering if you've received any updated feedback about the use of BAILI-four as the primary endpoint? Thanks so much.

[Eric Crombez, EVP & Chief Medical Officer at Ultragenyx Pharmaceutical]

So I mean, again

[Emil Kakkis, Founder, President & CEO at Ultragenyx Pharmaceutical]

All right, Eric, you want to do it? Go for it.

[Eric Crombez, EVP & Chief Medical Officer at Ultragenyx Pharmaceutical]

No, sorry, Emil. I didn't know if you guys were back online or not. Again, I guess I'll give it a start and you can certainly jump in. But the bar, I think for Angelman, it hasn't moved for us. So certainly, we had our interactions with the FDA. We do feel like we have full buy in with the study there. We do work through our statistical analysis plans with them as well.

[Eric Crombez, EVP & Chief Medical Officer at Ultragenyx Pharmaceutical]

So have been in communication with them. Again, falling back to the data we generated in Phase II, and that was quite a few number of patients there who continue to see the attainment of new developmental skills over time. We are not seeing a plateau effect. We are seeing them continue to gain new abilities and that's very important to them and their appearance. We have a lot of confidence in our primary endpoint with Bayley Cognition.

[Eric Crombez, EVP & Chief Medical Officer at Ultragenyx Pharmaceutical]

Again, Cognition is foundational to everything else you're looking at there, whether expressive language, receptive language, motor or anything else there. It is foundational and we think an appropriate endpoint. Again, we talked about using MDR eye and really being an ideal tool for these type of indications, as you're really looking at all of these aspects on a very straightforward transparent scoring system to really look at the benefit in totality and also allowing some variability between individual patients. So again, I think that rapid enrollment and really, it's not just 129 patients over seven months, it's 129 patients in a very complex study. And that really speaks to the enthusiasm with sites, with patients and their families to really gain access to this therapy.

[Operator]

Thank you. Our next question comes from the line of Maxwell Skor with Morgan Stanley. Please proceed with your question.

[Maxwell Skor, VP - Biotech Equity Research at Morgan Stanley]

Great. Thank you very much for taking my question. I was just wondering, can you elaborate a bit on how PRV proceeds are being factored into your path to 2027 GAAP profitability? Any insights into your relative confidence in receiving all three PRVs? Thank you.

[Emil Kakkis, Founder, President & CEO at Ultragenyx Pharmaceutical]

Yes. Well, obviously, PRV are important part of it. And I'll let Howard maybe talk through that, the PRVs and how we're working them into our cash plan.

[Howard Horn, CFO & EVP - Corporate Strategy at Ultragenyx Pharmaceutical]

Yes. We have PRVs from three of our programs, so 111, four zero one and one hundred forty three factored in. There has been a shift in timing on those, but we still think all of them come through. So yes, I think that's where I'd stop.

[Emil Kakkis, Founder, President & CEO at Ultragenyx Pharmaceutical]

Yes. If it's reauthorized, it makes it easier for the OI one. But if it's not, then the other two certainly could be will be done in time to achieve and we'd expect their value to be higher. So the net of whether it's three with reauthorization or two without, we think we're still up in the same place from a total cash.

[Maxwell Skor, VP - Biotech Equity Research at Morgan Stanley]

Great. Thank you.

[Operator]

Thank you. Our next question comes from the line of Yaron Werber with TD Cowen. Please proceed with your question.

[Analyst]

Yes. Congrats. This is Jaina on for Yaron. Congrats on the quarter and thanks for taking our question. You noticed that there's going be more of a prioritization on controlling spend, including stopping and delaying certain expenses.

[Analyst]

Can you give us more granularity about what this entails? And are you exploring the options in the event that responding to the CRL for UX 111 takes longer than expected? Thank you so much.

[Emil Kakkis, Founder, President & CEO at Ultragenyx Pharmaceutical]

Yes. Thanks. I think a lot of this is practical stuff that we're focusing on. And maybe Howard can go through it with you. But our expectation on the CRL part is to get through.

[Emil Kakkis, Founder, President & CEO at Ultragenyx Pharmaceutical]

I mean, I don't we've looked through the whole list. We actually had a lot of feedback already and we've already done a lot of the changes and things. So we don't really see there's anything in there that is undoable, very doable stuff. So we're working through it. So we're not really planning for us not to get it done.

[Emil Kakkis, Founder, President & CEO at Ultragenyx Pharmaceutical]

I think it will be done. And so far we think the FDA has been responsive in our discussions since then. Maybe Howard, you can talk about how we're managing costs.

[Howard Horn, CFO & EVP - Corporate Strategy at Ultragenyx Pharmaceutical]

Yes. Our goal has been and remains to be GAAP profitable, full year GAAP profitable in 2027. And so how you get there, of course, is continuing to grow the top line, but also making sure that we are good stewards of our cash. And so with some of the delays that we've experienced this summer, we did the natural thing, which is to delay those expenses and make sure we're being prudent and making sure we're using our money as well.

[Emil Kakkis, Founder, President & CEO at Ultragenyx Pharmaceutical]

Yes. It involves not hiring people that would have been hired for launches and managing other headcount. And in addition to that, just really scrubbing through all the spend that might that should be delayed as well and not just continue them ahead with momentum. We hope that bridges us to the point at which we will get the cash and manage where we're at. But we're I think it's just a prudent part of managing company in these situations and we've been through this before.

[Emil Kakkis, Founder, President & CEO at Ultragenyx Pharmaceutical]

So we're actually very facile at making the moves we have to make.

[Analyst]

Great. Thank you so much.

[Operator]

Thank you. Our next question comes from the line of Sami Corwin with William Blair. Please proceed with your question.

[Sami Corwin, Research Analyst at William Blair]

Hey, congrats on the progress and thanks for taking my questions. I had one on UX-one 111 and then a broader question on your AAV platform. Do you think that the fever leadership change will be helpful or kind of hinder the CRL resolution for UX-one hundred eleven? And then given the recent safety events with systemically administered AAV, are you thinking about modifying your immunosuppression regimens at all? Or are there any additional precautions you've implemented to decrease the risk of AAV related SAEs? Thank you.

[Emil Kakkis, Founder, President & CEO at Ultragenyx Pharmaceutical]

So, look, think there's a lot of very good people at FDA. They're still there doing their jobs. And our sense is that they won't impact their ability to do their jobs. I think in some ways it might be simpler for the next period because of the team that's head down in the work can do their work and work with us in solving these things. So I think it will stick to a very practical matter of fact line by line resolution of issues raised.

[Emil Kakkis, Founder, President & CEO at Ultragenyx Pharmaceutical]

And I think it's very doable without having high level leadership for these kind of things, these kind of resolutions. Because the clinical data were felt to be robust and strong, that's a little there's a little less uncertainty in judgment because the safety was excellent. There's no real question marks there. It's really more about getting the things boxes checked on all the CMC pieces, which we think we can do. So we're not so concerned about leadership for that particular aspect of it.

[Emil Kakkis, Founder, President & CEO at Ultragenyx Pharmaceutical]

With regard to the AAV platform, we're highly supportive of AAV as a treatment strategy. We obviously have a lot of investment in it. But for many of the liver targeted ones, we're doing it relatively lower doses compared to others. We have not seen substantial safety issues like you're talking about either death or very serious liver indicate complications. The lower dose we use, we think are in a very safe range and we feel very good on them.

[Emil Kakkis, Founder, President & CEO at Ultragenyx Pharmaceutical]

Now we are looking at enhancing immune modulation, but this is more about trying to alter or support more efficacy or managing anti transgene responses. We are looking at that in our Cohort four for UX111 to try to manage the immunological responses. But the drug worth is just a simple steroids fine. That's what we can get approved on. Our goal is always to continue to look to optimize.

[Emil Kakkis, Founder, President & CEO at Ultragenyx Pharmaceutical]

But it's not a central thing to try to prevent a death. It's more about trying to optimize the outcome. And we will look at and be more fast at looking at immune modulation where needed. But so far, we don't have any programs that are of the high dose type that have put created more complexities. But I want to say that if you have a lethal disease as Duchenne is or others, it is not inappropriate to have situation where that would challenge a patient.

[Emil Kakkis, Founder, President & CEO at Ultragenyx Pharmaceutical]

And I think parents should have the right to make their decisions about the risk benefit. And we think that a lot of these horrible diseases are a death sentence and a horrible death sentence for families and they should be given the opportunity to make their decision on what's the best healthcare for their kid. And I think they can are capable of making that decision with an approved product.

[Sami Corwin, Research Analyst at William Blair]

Thank you.

[Operator]

Thank you. Our next question comes from the line of Maury Raycroft with Jefferies. Please proceed with your question.

[Farzin Haque, SVP & Biotechnology Equity Research Analyst at Jefferies Financial Group]

Hi, this is Farzin on for Maury. I wanted to clarify for statrusumab, if you can provide more granular timing on the Street disclosure, that last patient visit should be October, so it sounds like there'll be no DMC review and you'll be unblinded to the data. So technically, it should be faster than two months than it took for IA2?

[Emil Kakkis, Founder, President & CEO at Ultragenyx Pharmaceutical]

Hi. So you'd like what day and time the data coming out? I'm sure we can print out that. Well, yes, the last patient I remember, there's this whole process of getting all the last data sets, the x rays reviewed, finalized, clean, no issues. We have to look at blinded and make sure there's nothing wrong, no aberrations.

[Emil Kakkis, Founder, President & CEO at Ultragenyx Pharmaceutical]

It's a Phase III study, so it's not something you want to rush through. It's the final assessment. We want to make sure we do it carefully. We've been saying it's around the end of the year. It could be before the end of the year.

[Emil Kakkis, Founder, President & CEO at Ultragenyx Pharmaceutical]

It could be just after the end of the year. It's somewhere in there. But we don't want to nail it down because frankly it's not possible to and we're not trying to be cagey here. It's just that we want to make sure we allocate time as provided to get the study closed out absolutely perfectly and every aspect of the study is perfect. We owe it to the patients and our investors to make sure that everything is perfectly correct when we go out and release data.

[Farzin Haque, SVP & Biotechnology Equity Research Analyst at Jefferies Financial Group]

Makes sense. And then for the instrument, the demand is there clearly and these are all deletion patients. But can you talk more about patient baseline profile relative to your Phase onetwo enrolled space? And then should we expect more durability data from the Phase onetwo cohort of patients maybe this year?

[Emil Kakkis, Founder, President & CEO at Ultragenyx Pharmaceutical]

Well, patients in the Phase two and now enrolled in the Phase three are essentially the same. They're four to 17 year old deletion only patients. So they're actually identical, the same criteria were used. So they're really very comparable. So whatever we saw in Phase II is probably pretty much what you should see in these Phase III patients.

[Emil Kakkis, Founder, President & CEO at Ultragenyx Pharmaceutical]

So with the AURORA study, we're going to look at younger patients or older patients with deletion. We'll also look at patients that have missense mutation or the ICD UPD type. So we're going to gain knowledge. The idea was to gain sufficient safety data to show that you can administer the drug and then show that their efficacy, even though in an open label format, that the efficacy is comparable to the effect that we will demonstrate and prove as a cause and effect of the drug in the randomized control study. So that's the idea on the approach we're taking. Did I answer your question?

[Farzin Haque, SVP & Biotechnology Equity Research Analyst at Jefferies Financial Group]

Yes. And should we see more follow-up data from the Phase one to this year?

[Emil Kakkis, Founder, President & CEO at Ultragenyx Pharmaceutical]

We hadn't planned right now. I mean the team is working on two Phase three programs right now and that is our focus. And the last thing I want to do is put another item on their plate of running more. Patients continue to get drug and are doing fine and we're encouraged with it. But we hadn't planned another kind of data yet.

[Emil Kakkis, Founder, President & CEO at Ultragenyx Pharmaceutical]

We got to get the Phase three done and do them well.

[Farzin Haque, SVP & Biotechnology Equity Research Analyst at Jefferies Financial Group]

Got it. Thank you so much.

[Operator]

Thank you. Our next question comes from the line of Jack Allen with Baird. Please proceed with your question.

[Jack Allen, VP - Biotech Senior Research Analyst at Baird]

Hey, thanks so much for taking the questions and congrats on the progress. I wanted to ask a couple on the cetuzumab program. As it relates to Orbit, what kind of standard deviation are you seeing in any blinded data that you've seen? How confident are you in the existing statistical analysis plan that you have outlaid? And do you think there are any needs to update that SAP? And then I have

[Eric Crombez, EVP & Chief Medical Officer at Ultragenyx Pharmaceutical]

a quick follow-up as well.

[Emil Kakkis, Founder, President & CEO at Ultragenyx Pharmaceutical]

Yes. We haven't really talked to standard deviation. I know everyone is trying to calculate dispersion. You didn't say dispersion, though, so but everyone is also saying dispersion just to show their at the level of statistician operating here. I know everyone's trying to do the math for us.

[Emil Kakkis, Founder, President & CEO at Ultragenyx Pharmaceutical]

We haven't put out the standard deviation. I don't really even know it off the top of my head right now. But there is a significant amount of variation because we've said about a third of the patients had fracture rate at baseline from three or above and about two thirds below. We also have age range of five year olds up to 25. So there's a bit of range in those things.

[Emil Kakkis, Founder, President & CEO at Ultragenyx Pharmaceutical]

Those are all factors in the standard deviation, both the standard deviation of the AFR, but also bone BMD response, etcetera. We have comps in the SAP in the sense that the negative binomial model actually is the best way to look at this kind of fracture data. And frankly, today, I actually did a little AI search, which you can do yourself and look up negative binomial and fractures, and it'll tell you actually this is the best method, you can do it yourself. And it says among all the methods, there's some comparison papers, it's the best method. Now there are things in detail to that, like what co variables, what are the items that contribute to variation that we can look at.

[Emil Kakkis, Founder, President & CEO at Ultragenyx Pharmaceutical]

Those are basically tweaks to the model that you can make. And usually in any stat plan, you offer some flexibility in what co variables you might use because you have to control for contributions of variation, which include the baseline AFR. It could include the type OI. It could include the age, right? Those are three obvious ones that would be potentially included.

[Emil Kakkis, Founder, President & CEO at Ultragenyx Pharmaceutical]

So those are some of the tweaks you would do to a final analysis plan, but the basic negative unknown model is set and we're confident in it as a strategy. And we just want to make sure we're using the right set of co variable to help control for baseline variation that's not related to actual treatment effect. And that will help assure that we get the best result.

[Jack Allen, VP - Biotech Senior Research Analyst at Baird]

Great. Great. That's super helpful context. And then you did mention that the Phase II seems to be demonstrating a very durable effect and even a deepening of response over time, at least that's what how I would characterize some of your earlier comments from sitrutumab. I just wanted to ask if there are any plans to present updated data from the Phase II cohort of 24 patients and when we may see that data set, if there are plans?

[Emil Kakkis, Founder, President & CEO at Ultragenyx Pharmaceutical]

Well, don't have plans yet. The study is ongoing. The patients are doing really well and we consider doing that at some point. We haven't made a specific plan yet to do it.

[Jack Allen, VP - Biotech Senior Research Analyst at Baird]

Got it. Thanks so much. Congrats on the progress.

[Operator]

Thank you. Our next question comes from the line of Hana Wei with Guggenheim Partners. Please proceed with your question.

[Hannah Wei, Senior Research Associate at Guggenheim Partners]

Hi, this is Hannah on for Debjit. Thanks for taking our questions. We have a question regarding OI program. Could you clarify which bisphosphonate therapy for patients were on prior before entering the August study? And roughly how many patients were on request? Thank you.

[Emil Kakkis, Founder, President & CEO at Ultragenyx Pharmaceutical]

Yes, we haven't disclosed which bisphosphonate is on, but we have said the fast injury, think it's greater than ninety percent have had bisphosphonates on board like a large fraction. So it's primarily because enrolling patients with a higher fracture rate, the higher ones are in the study. So the fraction a bit on bisphosphonates were I think, above ninety percent. But we haven't said which ones. It's several different ones. It wouldn't help you.

[Hannah Wei, Senior Research Associate at Guggenheim Partners]

Got it. Thank you.

[Operator]

Thank you. Our next question comes from the line of Raghuram Selvaraju with H. C. Wainwright. Please proceed with your question.

[Daniel Smith, Equity Research Associate at H.C. Wainwright & Co.]

Good afternoon. This is Dan on for Ram. Thanks for taking our questions. Congrats on the beat. So have you noticed or has Corinne mentioned anything notable about The U.

[Daniel Smith, Equity Research Associate at H.C. Wainwright & Co.]

S. Or Canadian Crysvita market? The royalties appeared kind of flat on a Q1 year over year basis, but increased over 70% Q2 year over year. Do you have any rationalization for that? And how much of that increase do you expect to be sustainable in year over year quarter comparisons moving forward? Thank you.

[Emil Kakkis, Founder, President & CEO at Ultragenyx Pharmaceutical]

Yes. Well, I think there's always a little lumpiness in those regions because of how the ordering buying. I haven't any particular explanation.

[Emil Kakkis, Founder, President & CEO at Ultragenyx Pharmaceutical]

I don't know, Eric, if something of insight that you have, but I think there's just regional lumpiness when the governments are managing what goes on?

[Erik Harris, EVP & CCO at Ultragenyx Pharmaceutical]

Yes. No, we think the underlying demand has been pretty consistent and pull through. And as Emil had mentioned, the ordering patterns have just been a little lumpy.

[Emil Kakkis, Founder, President & CEO at Ultragenyx Pharmaceutical]

We're not making more than that for you. You.

[Daniel Smith, Equity Research Associate at H.C. Wainwright & Co.]

Thanks. I'll take the line.

[Operator]

Thank you. Our next question comes from the line of Luca Eci with RBC Capital Markets. Please proceed with your question.

[Shelby Hill, Biotech Equity Research Associate at RBC Capital Markets]

Great. Hi, team. This is Shelby on for Luca, and thanks for taking our question. Emil, we have heard you in recent interviews noting that the FDA asked for things like more probes in your shipping validation for the Sanfilippo CRL, as well as an inspector who was particularly stringent with his review. Can you expand on that?

[Shelby Hill, Biotech Equity Research Associate at RBC Capital Markets]

And then maybe bigger picture, can you share your opinion on whether you think the FDA is missing the forest for the trees here? Any color there, much appreciated. Thanks.

[Emil Kakkis, Founder, President & CEO at Ultragenyx Pharmaceutical]

Well, I think one of the FDA's job is to is actually to check every tree in the forest. That's part of the rigor of the process. So if there's a CRL, there's a lot of bits and pieces because there are a lot of bits and pieces. I think I'd say these are all things that need to get taken care of and there are lots of parts and pieces to it. So they're I think they're doing their job with regard to that detail.

[Emil Kakkis, Founder, President & CEO at Ultragenyx Pharmaceutical]

What it should be CRL or could we have done it in time? Those are questions you could ask. But we're going to do the work they ask for. And the inspector and all that, I think it doesn't matter. In the end of the day, we have a CRL listed issues to do and we're going to do them and we're doing them.

[Emil Kakkis, Founder, President & CEO at Ultragenyx Pharmaceutical]

And I think we'll be able to work that out with the agency and get it done. But there are times when the FDA has to focus on certain details. It's part of the rigor they apply and we appreciate that particularly in CMC rigor is essential and there are reasons for a lot of things that relate to things that And so we are going to comply and improve what we can with everything we do.

[Operator]

Thank you. And ladies and gentlemen, we have reached the end of the question and answer session. I'll now turn the call back over to Joshua Higa for closing remarks.

[Emil Kakkis, Founder, President & CEO at Ultragenyx Pharmaceutical]

Thank you. This concludes today's call. If there are additional questions, please contact us by phone or at irultragenyx dot com. Thank you for joining us.

Participants

Executives

• Joshua Higa, VP - IR
• Emil Kakkis, Founder, President & CEO
• Erik Harris, EVP & CCO
• Howard Horn, CFO & EVP - Corporate Strategy
• Eric Crombez, EVP & Chief Medical Officer

Analysts

• Will Soghikian, VP - Equity Research at Leerink Partners
• Mehdi Goudarzi, Biotech Equity Research Analyst at Truist Securities
• Gena Wang, MD - Biotech Equity Research at Barclays
• Tazeen Ahmad, MD - US Equity Research at Bank of America
• Analyst
• Kristen Kluska, Equity Research Analyst at Cantor Fitzgerald
• Yigal Nochomovitz, Director at Citigroup
• Tommie Reerink, Biotech Equity Research Associate at Goldman Sachs
• Maxwell Skor, VP - Biotech Equity Research at Morgan Stanley
• Sami Corwin, Research Analyst at William Blair
• Farzin Haque, SVP & Biotechnology Equity Research Analyst at Jefferies Financial Group
• Jack Allen, VP - Biotech Senior Research Analyst at Baird
• Hannah Wei, Senior Research Associate at Guggenheim Partners
• Daniel Smith, Equity Research Associate at H.C. Wainwright & Co.
• Shelby Hill, Biotech Equity Research Associate at RBC Capital Markets