We are continuing to do some work. It’s not a big burn factor but there are some experiments going on to look at both the 2x FPD mouth and some other aspects of optimization. But we’re really encouraged by the potential that we think is greater than the monoclonal antibodies reducing amyloid in the worst model out there which is the 5x FAD. And so we think there’s enough interest and — with our systems and Pinnacle PCA manufacturing it really puts us in a position actually being able to approach a large market indication, which — and I think it would be from a response we’ve seen from KOLs in our market work there’s a great deal of interest, and something that wouldn’t cause area inflammation but allow a single-shot therapy for a treatment for a disease this kind.
So, we’re excited about the spin out and we’ll put more information out when we get we get it done as we progress.
Laura Chico : Thanks very much.
Operator: Thank you. One moment for questions. Our next question comes from Ed Arce with H.C. Wainwright. You may proceed.
Unidentified Analyst : Hi. Good afternoon everyone. This is Thomas here asking a couple of questions for Ed. Appreciate for taking my questions. Perhaps for III for Santa Riposyndrome. Can you discuss some major topics that you plan to discuss with the FDA in the upcoming meeting? And what do you plan to achieve coming out the meeting?
Emil Kakkis: Yes. Well in the MPS IIIA program our main focus of these discussions is on how to qualify apertsulfate as a biomarker for accelerated approval. I’d point out to you we’re also measuring clinical data and we’re encouraged by the clinical data as well. I mean the patients are continuing to gain ground gain development skills over time. And I think that this shows that the gene therapy is working. While we could potentially get approval by just following these patients clinically, our hope is to be able to get the biomarker accepted. There’s been a challenge with the agency. I think Peter Marks has publicly supported the use of biomarker and including this biomarker at the recent MPS conference, but we have to get them through the details of how that’s done.
I think as a company we’re as well versed as anyone how to explain the biomarker and how to analyze the results. But it is a situation where you have a neuro degenerative order with a relatively slower progression through multiple years. And therefore the qualification takes a little more work to figure out and support. But I’d say everything I’ve seen in our program and multiple other clinical programs from other parties shows that these markers are – represent the underlying disease and their reduction through either enzyme or gene therapy is showing a meaningful reduction that will have important clinical benefits. So we’re confident about the value of the treatment and we’re continuing to work with them on what it takes to qualify and we’ve had I will say for the program we’re also working on the CMC side production as we had to take that over.
That is going to take some time. So in any case we wouldn’t be ready to file until we were able to run the CMC side of the equation. This is not a priority program for the company so we have managed it in a more capital efficient way as best we can, given but our hope would get CMC straight as well, which will be part of the factor that will determine our ability to file it in addition to our discussion with the FDA.
Unidentified Analyst: Understood. Perhaps just one more question from us. This one for GTX-102 for Angelman syndrome. As we expect the expansion cost data in first half of 2024. What – do you expect the median time duration amongst these patients would be? And what are your some initial thoughts on possible registrational endpoints?
Emil Kakkis: Well the duration – most of the patients 20 that will show will have only day 170. We’ve shown you that in the most recent extension data the day 254 looks better than day 170. However, the dose loading – the average dose loading of expansion cohort is higher than what we just showed you before. So they’re actually getting more drug – so our expectation by day 170 will see more effect is our expectation. We will have 10 patients that should take us through to 254. Allow us at least a sense for how that’s going and give us an idea. So our expectation for a pivotal study would be that it would be somewhere in the range of seven to nine-month kind of study where we’ve loaded and gone through a few maintenance doses.
We think that’s a sweet spot for improvement and change without giving kids too many placebo intrathecal injections these are people’s kids and you’re putting – doing lumbar punctures in them. So I think that combination will give us enough time to separate. And we think it would be long enough. I’m sure the FDA would always want longer but I think we’re getting close to the one-year point but I would hope that maybe it’s going to be seven to eight to nine months would be a reasonable place to show substantial separation and we look at day 254 kind of a place where you could see a lot of movement in the development of these kids.
Unidentified Analyst: Got it. Thank you again for taking my questions.
Emil Kakkis: Good.
Operator: Thank you. I’d now like to turn the call back over to Joshua Higa for any closing remarks.
Joshua Higa: Thank you. This concludes today’s call. If there are any additional questions, please contact us by phone or at ir@ultragenyx.com. Thank you for joining us.
Operator: Thank you. This concludes today’s conference call. Thank you for participating. You may now disconnect.
