REGENXBIO Inc. (RGNX) Earnings Call Transcript & Summary

Good morning, everyone. Welcome to day 1 of our Piper Sandler Healthcare Conference. My name is Yas Rahimi. I'm a biotech analyst here at Piper Sandler. Really thrilled to have the team from REGENX here. 2026 is a big year for REGENX. You guys have been the pioneers in gene therapy.

Would love to kind of start off the role that sort of your views into 2026 and how you're thinking about some of the key inflection points, and then we'll go through each program one by one.

Sure, yes. Really big year for us in terms of -- we have really solid dates in mind for some really key milestones. The first is, first quarter February PDUFA date for our Hunter program. I've been with that program for 9 years now. So it's exciting to see it getting to this point of review and we've had good success over the summer with the inspections. But next on the list is in early Q2, we've guided to top line data for our Duchenne program. So we completed enrollment last October and look forward to the results there. I can talk about more in depth on that. And then in September this year, we announced completion of enrollment. I think they're the largest gene therapy trials ever conducted with AbbVie. So we are now pointing to top line data for the subretinal program for wet AMD late next year.

Wonderful.

Lots to look forward.

Lots to look for, lots of rich catalysts that are here upcoming. You guys have made a tremendous amount of investment and work and hard work went into building a manufacturing facility. So help us understand sort of the capabilities that the facility has as one of the leaders in the gene therapy space.

Sure. Yes. So we started probably around 10 years ago when I joined building up the CMC approach. And I think historically, FDA and others have been pretty critical of gene therapy manufacturing, saying it needed to be modernized and that's exactly what we set out to do. So if you walk into our manufacturing facility located in Rockville, it will look like a biologics plant, suspension bioreactor with HEK293 cell line that we use. And we've really sort of cracked the code on gene therapy expression levels for vector. We've published some of that at ASGCT. And I think importantly, having control of manufacturing, particularly for the Duchenne program, where there's a really high vector requirement is a huge asset to us and a differentiator.

Wonderful. Maybe let's talk about RGX-121, which is upcoming here with PDUFA date in February. I think recently, you noted that the inspections have been completed. PDUFA date is on track. Just kind of help us understand sort of what is left to do between now and PDUFA and what your disclosures are going to look like between now and then?

Well, we'll certainly give a disclosure around February when the PDUFA date comes. The BLA was submitted as a rolling BLA. So we submitted nonclinical and CMC and then the clinical module last. So as you could expect, most of the review at this point is down to the clinical module. We published data in September with full 12-month data on all of the patients in the pivotal, which looked really exciting. And so yes, we're looking forward to proceeding to a PDUFA date, hopefully, a positive decision. I think the manufacturing plays into that as well. The facility was inspected as part of that in the summer, and we got out of that with no observations, which is pretty rare. So we feel like we've derisked one key aspect of the gene therapy world in terms of CMC and nonclinical looking really positive.

And maybe it would be also great to think about sort of how you envision commercialization, we transition to become a commercial company with manufacturing and scalability on hand, which will be maybe a question that comes up is like finding patients, warehousing them, what work has been done hires in terms of building the commercial team?

Yes. We signed a deal early this year with NS Pharma. So we are in a partnership in which NS Pharma will handle the commercialization aspect. We felt it's a bit too early for us to build out a sales team for an ultra-rare indication. But the benefit we have is we do control the manufacturing supply chain. We'll have a lot of input, obviously, into the commercialization because many of the sites we're going to will be the same as what we used in the clinic as well. MPS is ultra-rare disease and finding patients is actually pretty straightforward. There's emerging, I think I heard 40% of the States in the next 1.5 years will be doing newborn screening. And so that will be an automatic funnel to find patients. They're very aware of our program. We've had a 10-year relationship with the MPS society that will help us greatly with that. So we're looking forward to it. And I think we have all the elements for a successful launch.

How do you think 121 will play into the market?

I think onetime gene therapy is really truly differentiating. So if you think about the burden of care, which currently, there aren't any treatments available for the CNS manifestation. But for things like enzyme replacement therapy, patients have to come in many times weekly for infusions and imagine the burden of having a child. So a onetime gene therapy, I think, will be a very powerful alternative for patients, and we expect really strong adoption.

Wonderful. As many investors are also aware, first of all, you will be the first gene therapy to enter the ERT market, which would be another key milestone for the space. Investors who follow the program understand that DNL310 also has an upcoming PDUFA date on April '26. So maybe help us understand sort of the evolving landscape when it comes to the space with multiple gene therapy programs available and the differentiations of them?

Sure. I just talked to a couple of people within patient advocacy groups. It's been 20 years since they've had anything new approved. So having 2 programs potentially approved is great for patients. Again, I like our position in the sense of a onetime gene therapy. I think our data -- particularly, we have data in younger patients. So I think in terms of who are the right patients to dose and coming off newborn screening, once the damage is done, it can't be undone. So early treatment is going to be important. And I think the strength of our data is in that younger patient population.

Great. Team, would love to talk about 202 and DMD. Maybe start off with helping us understand what is the strategic interest in 202 for DMD?

Yes. I think it plays out a lot of strengths within the company. Number one, it's in rare disease, which we just talked about the Hunter program. That's a key element of our portfolio. Number two, our Chief Science Officer, Olivier Danos, has been working in Duchenne for 25 years or so. And so he had a lot of input, obviously and drove the design of the construct, which includes the C-terminus. And if you go all the way back to the Elevidys AdComm, you'll see FDA reviewers talking about the value of making microdystrophin more like natural dystrophin. And that automatically includes, if you do that, the C-terminus, which we were able to accomplish. So what that does is it helps with restoring function once the muscle has been damaged through exercise. So that gave us promise of delivering better functional benefit. But then I think the last piece of the puzzle -- well, maybe there's 2 more, but one is the immune suppression regimen that we're using. So far, we've had no SAEs in our Phase I/II study. We'll be happy to roll out our safety update in the Q2 top line data. We feel very positive about that. And then playing into that is the manufacturing process. We're at 80% full capsid. So the majority of the product is the intended product and that's what allows us to maximize the dose and give the best possibility for functional benefit.

And how do you think it differentiates versus other gene therapy programs in DMD?

I think that when we -- if we look at our Phase I/II data and we look at the benefit to risk profile, I think we have the best product in development. And I say that because we're seeing improvement in patients that are 7 and older, where automatically, those patients are normally in a decline phase of their disease. We're seeing those children improving in function, not just stabilized. And we're also, as I mentioned, not seeing safety events. So you put the 2 together, I think we have a compelling case.

The data is on track for 2Q of next year. Maybe just housekeeping items. What type of data will you have on hand at the time of the disclosure? And what is sort of the bar for success or the expectation going into the readout?

Yes. So we'll have in Q2, we'll have for all 30 patients, overall safety update and we'll also have data around the primary endpoint, which is microdystrophin with proportion of patients at 10% and above for microdystrophin. We'll also have functional data, I would say, on roughly 1/3 of those patients, it depends on visits and timing, et cetera. And key is at 12 months. We don't believe data earlier than that because it could be subject to immune suppression, et cetera. And more importantly, that's what allows us to match to the external controls because most of the NSAA data for external controls is a 12-month data point. So what success looks like is we want to see differentiation on time to rise, but even more importantly, I think, on NSAA, which we haven't seen in other programs. And that's what we're seeing in our early Phase I/II data at the pivotal dose. So same safety, same -- if we can just replicate what we've done in Phase I/II with 30 patients in the pivotal, we'll be in great shape, I think, in terms of the application.

And team, obviously, the data readout is critically important, but what is your planned path that data? Obviously, you'll be getting ready to file. Is this something you want to embark on commercializing on your own? Or are you actually actively looking to partner in this program? What are some of the key factors that you're going to be making that decision, obviously, post the data?

Yes. No, I think we love having the program on our own within our full control. And the program to date has been largely U.S.-based. So moving as fast as we can to an approval in the largest market. We're definitely open to a partnership that could broaden the scope of the program to a global enterprise, but I think that's not our current near-term focus. And we have everything we need to do it. We've got the manufacturing capability. We've got a sales team that's being brought online as we speak. So we'll be ready, and we're pointing towards an initial BLA filing in mid-2026.

Perfect. And Curran, you alluded to sort of the commercial capability. So the advantage of getting ready for 121 and then for the DMD program, sort of the learnings and the capability of scaling up, like what is -- if you could just touch even though these are different programs, different constructs, but there's a lot of read-through when it comes to scalability of manufacturing.

Yes. I think there's a couple of things. Number one, having a facility that's been inspected with no observations, that will be the same facility that's used for the 202 program. So we feel that element is derisked. And the process looks almost identical, just a couple of changes there. Interestingly, the -- as well, the partnership with NS Pharma will help us on the supply chain aspect, delivering to patients. But don't forget, we also were the initiator early on of Zolgensma. It's our IP. And many of the dosing sites for Duchenne are also the same for SMA. So there's a synergy there that we're learning from as well.