Welcome, everyone to the First Quarter 2025 REGENXBIO Earnings Conference Call. At this time, all participants are in a listen-only mode. After the speakers' prepared remarks, we will conduct a question-and-answer session. As a reminder, this call may be recorded. At this time, I'd like to turn the conference over to Patrick Christmas, Chief Legal Officer of REGENXBIO. Please go ahead.

Good afternoon, and thank you for joining us today. Earlier this afternoon, REGENXBIO released financial and operating results for the first quarter ended March 31, 2025. The press release is available on our website at www.regenxbio.com. Today's conference call will include forward-looking statements regarding our financial outlook in addition to regulatory and product development plans. These forward-looking statements are subject to risks and uncertainties that may cause actual results to differ from those forecasted and can be identified by words such as expect, plan, will, may, anticipate, believe, should, intend, and other words of similar meaning. Any such forward-looking statements are not guarantees of future performance and involve certain risks and uncertainties. These risks are described in the Risk Factors and the Management's Discussion and Analysis section of REGENXBIO's annual report on Form 10-K for the full year ended December 31, 2024, and comparable Risk Factors sections of REGENXBIO's quarterly reports on Form 10-Q, which are on file with the Securities and Exchange Commission and available on the SEC's website. Any information we provide on this conference call is provided only as of the date of this call, May 12, 2025, and we undertake no obligation to update any forward-looking statements we may make on this call on account of new information, future events, or otherwise. Please be advised that today's call is being recorded and webcast. In addition, any unaudited or pro forma financial information that may be provided is preliminary and does not report to project financial positions or operating results of the company. Actual results may differ materially. I'll now turn the call to Curran Simpson, President and CEO of REGENXBIO.

Thank you, Patrick, and thank you, everyone for joining us today. We've had an impressive start to the year at REGENXBIO and are in store for an exciting remainder of 2025. Today, you will hear about our strong late-stage clinical progress, which sets us up to potentially bring multiple first or best-in-class gene therapies to patients over the coming years. We will also discuss other key elements that we believe position us to successfully transition to the commercial stage, including our U.S.-based in-house commercial-ready manufacturing and the broad potential to secure non-dilutive funds. With me on today's call are Dr. Steve Pakola, our Chief Medical Officer; and Mitch Chan, our Chief Financial Officer. I'll start with a review of recent business highlights, then turn it over to Steve and Mitch for clinical and financial updates. Then, I'll have a few closing remarks before opening the call for Q&A. Starting with our most advanced program, RGX-121 or clemidsogene lanparvovec, the potential first gene therapy and one-time treatment for MPS II or Hunter syndrome, a devastating disease that affects approximately 2,000 patients worldwide. Any day now, we expect the FDA acceptance of the BLA, which we submitted under the accelerated approval pathway in March 2025. RGX-121 remains on track for potential FDA approval in the second half of this year. Earlier this year, we established a key strategic partnership with Nippon Shinyaku to commercialize our neurodegenerative franchise, including RGX-121 and RGX-111 for severe MPS I, and commercial preparations are progressing well. Together with Nippon, our goal is to deliver RGX-121 to patients beginning in the first half of 2026. Accelerating quickly right behind RGX-121 is RGX-202, our next-generation candidate for Duchenne muscular dystrophy. I am pleased to report that our pivotal study continues advancing rapidly. We have surpassed 50% enrollment for our pivotal dataset. We're seeing increased interest and enthusiasm from the patient community about RGX-202 and its differentiated profile. And we remain on track to submit a BLA in mid-2026 and seize our unique second to market or fast follower opportunity in Duchenne. Positive input from our growing investigator community supports our belief that RGX-202 has the potential to be a preferred and differentiated treatment option. It's important to keep in mind that one, RGX-202 is the only investigational next-generation DMD gene therapy in pivotal study and the only investigational therapy with both robust microdystrophin and functional data available. Two, RGX-202 has the potential to be approved for patients aged one to three, who currently have no access to gene therapy. And last, DMD represents a large addressable market, with over half of the prevalent DMD population projected to remain untreated as of 2027, the expected year of RGX-202's commercial launch. Given our strong and rapid clinical progress, conviction in our differentiated profile and in recognition of the ongoing unmet need, we will begin producing RGX-202 commercial supply at our Manufacturing Innovation Center here in Rockville, Maryland in the third quarter of this year. With full clinical and planned confirmatory supply already in hand, we will build commercial inventory to be prepared for a smooth launch and meet patient needs immediately upon the potential approval of RGX-202. As a reminder, our Manufacturing Innovation Center is a state-of-the-art integrated GMP facility that can produce up to 2,500 doses of RGX-202 annually, enough to treat approximately one-fifth of the estimated North American DMD population, all while delivering industry-leading purity levels in Duchenne with over 80% full capsids. We look forward to sharing additional Phase I/II functional data for RGX-202 in the first half of this year as we aggressively advance towards commercialization. Moving to our retinal programs, we continue to work closely with our partner, AbbVie, to progress ABBV-RGX-314 or surabgene lomparvovec. ABBV-RGX-314 is advancing in two pivotal studies for subretinal wet AMD, one Phase II study for suprachoroidal wet AMD, and preparations for a pivotal program are underway in diabetic retinopathy or DR using suprachoroidal delivery. We remain on track to be the first gene therapy on the market for wet AMD with a product that has demonstrated compelling durability and strong patient interest. Both wet AMD and DR represent large multi-billion dollar commercial opportunities, and we believe ABBV-RGX-314 has the potential to preserve vision and serve as a meaningful alternative to today's standard of care. In summary, we remain excited for and are well positioned to deliver on the opportunities ahead of us. With that, I would like to now turn the call over to Steve for an update on our clinical programs.

Thank you, Curran. I'll start with RGX-202, a potential one-time gene therapy for the treatment of Duchenne. RGX-202 uses the NAV AAV8 vector and is the only microdystrophin construct to include the C-Terminal domain, a key element of naturally occurring dystrophin critical to protecting muscle from contraction-induced damage. This novel construct, combined with the highest purity levels in the field, make RGX-202 a potential best-in-class gene therapy for Duchenne. As Curran mentioned, I'm pleased to share that today, we announced the pivotal phase of the AFFINITY DUCHENNE trial is beyond 50% enrolled. Our accumulating Phase I/II results are showing impressive evidence of differentiation on safety, biomarker and functional outcomes. This is driving increased excitement throughout the Duchenne community, giving us further confidence as we move toward our target of completing pivotal enrollment in the second half of this year. This trial is enrolling ambulatory patients aged one and above, generating data where limited results exist for Duchenne gene therapies. Based on the clinical profile, and in partnership with our investigators, we expanded the inclusion criteria to a broader range of exon mutations. Additional trial sites continue opening in the U.S. and Canada, and we are making great strides in our pivotal strategy to enroll across a wider age range with an aim to secure a broad label supported by a clear and robust product profile. In November, we reported positive safety and efficacy data from the Phase I/II study, including positive functional outcomes from the first five participants at nine and 12 months. These results presented last November showed RGX-202 recipients exceeded external natural history controls and established benchmarks for clinical outcomes. Specifically, we observed functional improvements in all five evaluated patients, including those at dose level two, consistent, robust expression, transduction and localization of our differentiated RGX-202 microdystrophin in muscle, with all participants above 10% expression. We have also seen a favorable safety profile with no serious adverse events or AEs of special interest. Building on this data, in March, at the 2025 MDA conference, we presented new biomarker data from two patients, including the first data from our cohort of patients under four years of age. This patient, aged three at dosing, had a microdystrophin expression level of 122% of control. Patients aged one to three represent a significant portion of the prevalent Duchenne population, yet this group has no access to approved gene therapy. Overall, the Phase I/II data show consistent microdystrophin expression in all 12 patients spanning all age groups, functional improvements and evidence of altering the trajectory of disease, and a favorable safety profile. As the program advances, we expect an increased focus on the dose level two cohort as these patients receive the commercial dose level. We look forward to sharing additional data from the Phase I/II study in the first half of this year. Now on to our retina franchise, ABBV-RGX-314, which is being developed in collaboration with AbbVie to treat wet AMD and diabetic retinopathy, or DR. I'll start with ABBV-RGX-314 for DR being evaluated in the Phase II ALTITUDE trial using in-office suprachoroidal delivery. Like wet AMD, DR is a progressive disease that causes vision loss and ultimately blindness if not treated appropriately. As we've shared, we completed our end of Phase II meeting with the FDA in the fourth quarter of last year and are actively working with AbbVie on plans for our Phase III clinical program that would support global regulatory filings. We look forward to sharing more on that program as preparations progress. In wet AMD, we are evaluating ABBV-RGX-314 via two different delivery forms, subretinal and suprachoroidal. Within subretinal, we have two ongoing pivotal trials, ATMOSPHERE and ASCENT in the U.S., Europe, and Japan. These trials continue to progress well. As we've announced in January, enrollment of both pivotal trials is expected to complete this year, and we expect to share top line data in 2026. ABBV-RGX-314 is on track to be the first gene therapy on the market for wet AMD and is poised to deliver a compelling product profile based on the impressive safety and durability seen in our Phase I/IIa trial. In this trial, ABBV-RGX-314 achieved meaningful reduction in treatment burden and sustained treatment effect through four years. Overall, we remain encouraged by the ongoing progress with ABBV-RGX-314. I'd like to particularly highlight the differentiated safety profile observed in our in-office suprachoroidal program. This is particularly notable in the setting of short course seven-week prophylactic steroid eye drops, a significantly shorter regimen than those used in other gene therapy trials. This continues to support the potential of ABBV-RGX-314 as a meaningful treatment option for patients and physicians. Finally, turning to our MPS program. It's an incredibly exciting time for REGENXBIO in the Hunter syndrome community with the recent submission of our BLA for RGX-121. This filing is supported by data from the CAMPSIITE trial, which met its primary pivotal endpoint with high statistical significance. In addition, we previously reported that 80% of pivotal dose patients either discontinued enzyme replacement therapy or remained treatment naive, along with evidence of neurodevelopment improvement sustained through four years post-dosing. RGX-121 represents a potential significant advancement, not only improving patient outcomes, but also improving the daily lives of patients and families. As a one-time gene therapy, RGX-121 has the potential to achieve these benefits while also reducing the treatment burden and the significant amount of time families spend getting weekly enzyme replacement therapy. We look forward to an anticipated FDA approval decision in the second half of 2025. To conclude, we are making significant progress with data updates and trial progression across all programs in our pipeline. I'd like to thank all of the patients, families, clinicians, and patient advocacy representatives, who have been involved in and supported all of these trials. With that, I'll turn the call over to Mitch to review our financial guidance.

Thank you, Steve. REGENXBIO ended the quarter on March 31, 2025, with cash, cash equivalents, and marketable securities of $272 million compared to $245 million as of December 31, 2024. The increase was primarily driven by the $110 million upfront payment received under the Nippon Shinyaku collaboration and was partially offset by cash used to fund operating activities during the first quarter of 2025. R&D expenses were $53 million for the quarter ended March 31, 2025, compared to $54.8 million for the quarter ended March 31, 2024. The decrease was primarily due to clinical trial expenses for RGX-314 and RGX-202. We expect the balance in cash, cash equivalents and marketable securities of $272 million as of March 31, 2025, to fund our operations into the second half of 2026. This cash runway guidance is based on the company's current operational plans and excludes the impact of any future potential royalty income associated with RGX-121. If we include additional non-dilutive financing, we expect the cash runway to potentially extend well beyond 2026. For instance, some examples of our non-dilutive financing options include development and sales milestones, reversion of our royalty income and the potential sale of our Priority Review Voucher or RGX-121 if approved, which has recently sold for at least $150 million. Collectively, we have many non-dilutive financing optionalities that could extend our cash runway well beyond the second half of 2026.

Thanks, Mitch. As you heard today, there is tremendous momentum and strong execution across our pipeline to advance our programs towards key milestones. To recap, we have submitted our first BLA and our partnership with Nippon Shinyaku for our MPS programs is off to a strong start. We look forward to a potential FDA approval of RGX-121 this year. The pivotal study of RGX-202 is moving rapidly, and we believe remains well positioned to potentially serve as the next and preferred gene therapy in Duchenne. We are planning for success and will initiate commercial supply manufacturing in the coming months in anticipation of a 2027 commercial launch. We also plan to share updated functional data in the first half of this year. And with enrollment more than halfway through, we expect to complete enrollment of the pivotal study this year and share top line data in the first half of 2026. Our partnership with AbbVie is advancing towards multiple large global commercial opportunities. We expect to complete enrollment of two global pivotal trials for subretinal wet AMD and are working with AbbVie on a pivotal study in diabetic retinopathy in 2025. As we lead the way in AAV gene therapy, our team is looking forward to presenting at ASGCT this week. Our presentations in New Orleans highlight our in-house end-to-end capabilities and deep translational expertise. Presentations will include preclinical research supporting the novel construct of RGX-202, including the C-Terminal domain capsid discovery research and the RGX-202 manufacturing process development, enabling industry-leading purity levels in Duchenne gene therapy. We are in a very unique position in our industry. Each of our assets represents one-time treatments with the potential to transform the trajectory and management of disease for patients in need of new and better options, and are demonstrating beneficial differentiation against standard of care and available treatments. And we have a balance sheet that enables us to better navigate the current macroenvironment and execute against our near-term and exciting milestones. With that, thanks everyone for your time today. I'll turn the call over for questions.

Thank you. Our first question comes from Mani Foroohar with Leerink Partners. Your line is open.

Hey, guys. Thanks for taking the call. I've got two quick ones. I think first is around the timing for the Hunter BLA you mentioned. This month, I had a couple of people who reached out around timing, and I admit to doing this math myself. With 60 days marked out from March 13, it should be right around now. Is that math too close? Are we thinking about it wrong? I think there's just a little bit of sensitivity around any hypothetical FDA delay, or is this just we're not taking into account federal holidays? And then I have a follow-up.

Hi, Mani. Thanks for the call and the question. Yeah, we're certainly pointing towards imminent in terms of timing around the BLA acceptance. I think we feel really good about where the review stands. We've been getting regular interactions on a few areas, the information requests that normally come in as part of the review. And also we do orientation meetings early on regarding the submission and the BLA contents. All of that is pretty much business normal. We haven't gotten any questions that would lead us to believe otherwise. And so, I think you'll expect to hear from us soon about hopefully an acceptance.

Great. Moving on to a more substantive topic, you've likely observed how your competitor, Sarepta, has faced challenges both commercially and from a regulatory standpoint. Additionally, there have been leadership changes at CBER that have sparked a lot of discussions in the industry. I'm not the only one asking this, but how do you perceive the standards for approval in DMD on an accelerated timeline, particularly regarding biomarker data compared to functional data? Where does that conversation currently stand, and how has it changed in light of Sarepta's situation and the potential leadership shifts at CBER?

Yeah. Thanks. I think from the very beginning on the program, we've pointed towards accelerated approval pathway. Those were discussions we had with the FDA in our end of Phase II meeting, which were very positive and productive. Our intention from the beginning has been to provide functional corollary, if you will, to microdystrophin as part of the filing and review process. And so we feel really good about our data, the strength of the data in terms of safety profile and initial functional data that we provided. We really look forward to additional functional updates first half of this year to continue that story. And I think we've seen nothing but continued and maybe increased opportunity for us, given the benefit to risk ratio. We think we're developing, and the existence of what we think will be a very sizable prevalent market upon potential approval in 2027. So I think our conviction and our opportunity only continues to increase as the program evolves. And I think, in terms of how FDA would view that, I think certainly, Dr. Makary provided good context on rare disease development and the support for programs like ours, where I think we can provide benefit to patients.

Great. Thanks for that clarity, guys.

Thank you. Our next question comes from Gena Wang with Barclays. Your line is open.

Thank you for taking my questions. I will follow Mani's questions. I will also ask a few more. So giving a reason a Leviticus safety event, I will ask a very specific question, like, do you expect any changes from the FDA regarding requirement of the safety profiles? And also, for your pivotal study, any changes in terms of the enrollment speed and the patient type? And my second question, lastly, after the recent appointment of a new CBER Director, do you expect any changes on your accelerated approval path that was previously aligned with the FDA?

I think I'll take the last one. I think it's very early to project any potential changes in accelerated approval, but we certainly don't see any signs of that to date. Our program in terms of enrollment is absolutely on track with how we projected it. We feel highly confident that we will enroll the study of this year, the pivotal study of n equals 30. We'll continue to do enrollment throughout the remainder of the year as well to support our confirmatory study as well. And I think from the beginning of the program, I've been pointing towards, during the time of submission and review, having substantial functional data to accompany that. So I think I don't see anything emerging in some of the dialogue that we've heard from FDA that's contrary to that approach. So I think our plan is unaltered at this point regarding that. I do think that the strong functional data we reported in November, coupled with the safety profile to date that we've been able to portray in our earnings and press releases, really points towards potential improvement in benefit to risk for Duchenne patients, and we think that will be something that will be interesting to the review team as we complete our filing next year. I do think that this points towards our immune suppression regimen, which is, I think, innovative in the sense of proactively addressing known SAE types for Duchenne patients treated with high dose AAV. I think looking at that approach today is directly in line with potentially better outcomes for patients is what we've seen so far in terms of not just the experience during treatment, but then the post-treatment monitoring. And maybe I'll let Steve elaborate a bit on that from the clinical perspective. Steve?

Hi, Gena. Thanks. Thanks for the question. It is certainly an area of high interest in the Duchenne community, given the recent death, unfortunately, with the Leviticus program. I'd say the overarching aspect is that I think you've heard and seen and we certainly have seen this both at MDA and in our subsequent one-on-one discussions, is this just brightens the spotlight on safety. So I think even before this event, safety is king. And I think that's why a lot of the points that Curran mentioned are only giving greater comfort to our investigators and the patient families that they speak to about the differentiated aspects of our program. So I think this is why we designed the construct that we did. This is why over the years we've advanced, and we're very proud of our high purity level with the highest full-to-empty capsid ratio in the field and also the robust immune modulation regimen that mentioned. So I think those factors are giving us and the community comfort, and that's why we're absolutely on track with our recruitment.

I think I'd also point to the imminent review and outcome of the hopeful acceptance of the RGX-121 program. I think that will be sort of an early data point on accelerated approval. As you know, the Hunter program is following an accelerated approval pathway. In that case, we had a pre-BLA meeting that was also supportive for that program. So assuming that we conclude with an acceptance of that BLA in the near term, I think that will be a first data point to support that, that pathway is still viable and active process in FDA.

Thank you. Our next question comes from Judah Frommer with Morgan Stanley. Your line is open.

Yeah. Hi, guys. Congrats on the progress. Thanks for taking the questions. First, I was hoping we could get a little incremental color on the planning process along with AbbVie for the diabetic retinopathy Phase III trial. Any updated thinking on timing or potential impacts on the probability of recognizing that milestone? And then separately, just more broadly on interactions with FDA, given how many programs you have that you are interacting with them on, any changes recently you'd point to? Or is it sort of business as usual and contact with the same individuals as you'd anticipate? Thank you.

Thanks. I can address the second question first. We have been engaging in a considerable number of interactions with the FDA regarding submissions that have been filed and information requests that we are responding to. I would characterize it as business as usual. Without going into specifics about the types of information requests, none of them are raising concerns about the overall strategy of the program or the clinical data we've provided. They are mostly standard questions regarding the CMC process. The review teams appear to be stable and consistent with the teams we worked with last year. Regarding the Hunter program, we anticipate a near-term outcome regarding BLA acceptance, which we hope will indicate we're on track for a potential approval in late fall. For the diabetic retinopathy program, we continue to gather final feedback, as we mentioned earlier this year. AbbVie and we have received input from regulatory agencies in the U.S., EU, and Japan. In diabetic retinopathy, decisions need to be made regarding already established endpoints, such as two steps worsening or improvement. All of this feedback is being taken into account as we develop the final pivotal protocol. Once that protocol is finalized, we will begin site activation. We are still aiming for the first patient dose this year and will provide more specific timing as we approach that milestone.

Thank you. Our next question comes from Ellie Merle with UBS. Your line is open.

Hi, guys. This is Tejas on for Ellie. I guess just some of the incremental updates we can expect this year in DMD. So you mentioned some additional functional data in 1H. Am I correct in assuming that not at ASGCT? And then, is there an arena you'd expect to present that at, or should we expect a press release of that data? And then, you also mentioned starting commercial supply manufacturing later this year. You meant it's supply, but is it the same process that you're using in your current trials? And will you be able to provide any color on the CMC process with the FDA or any other meetings you might have on the statistical plan throughout the year? Thank you.

Sure. Let me begin with the CMC process. We indicated that we will start commercial production this year, which involves a combined effort. The batches produced during our first commercial production will also be submitted for the planned mid-2026 BLA. The validation process will follow the same procedures currently in use in the clinic, so no changes are expected for the patients involved in our pivotal program as we transition to commercial production. Additionally, our CMC approach using the NAVXpress platform is quite advanced, which we believe will be well-received by the FDA. This process has been reviewed in other programs, and the FDA has observed it during training sessions in the past couple of years. We are confident that our CMC approach is low-risk and produces highly pure capsids, which meet FDA expectations, with no significant changes needed to reach commercial production, allowing us to produce 2,500 doses per year. Returning to the earlier question about data, there are only about six weeks left in the first half of 2025. You can expect a press release regarding additional data, focusing on the dose level two patients treated in the Phase I/II study over a 12-month period, expanding the dataset to show the same functional outcomes observed in November. We will also provide updates on any recent biomarker data. The emphasis will be on how the pivotal dose level patients are progressing. Overall, the feedback we are receiving from sites and investigators is very positive right now.

Thanks. And just quickly, those pivotal dose patients in the Phase I/II will be included in the pivotal dataset for filing in mid-'26, correct?

Yeah. All patients that qualify for the inclusion criteria of the pivotal program would be included in the pivotal dataset.

Thank you. Our next question comes from Annabel Samimy with Stifel. Your line is open.

Hi. Thanks for taking my question. Just to go back to regulatory bodies and changes there. Just given the FDA's focus on safety with gene therapy, I guess we've been talking a lot about the rare conditions and how the carrier is very focused on the rare diseases and life-threatening conditions. Does that make it potentially harder for gene therapy in non-life-threatening conditions like retinal disease, for example? And are there any issues related to that for the DR indication, any delays there? And then one last question regarding regulatory bodies. RFK Junior just asked the HHS committee on genetic screening. So can you tell us how this might affect not MPS, but rather DMD and trying to get into the younger population and whether there are any complications there? Thanks.

Sure, I can address the second question. However, first, I’ll let Steve discuss any changes in the FDA’s position regarding retinal programs. Before Steve speaks, I want to emphasize that our focus on safety in non-rare conditions is paramount. The subretinal program shows incredible promise, and the safety profile in the data we've reviewed appears to be excellent. Now, I’ll hand it over to Steve for further details.

Sure. Hi, Annabel. So on retina, I think another broad aspect is, that's not an accelerated approval pathway. So, there's not a request for greater flexibility. So, fortunately, there we know the regulatory route and we're already executing on that, for example, in subretinal. And we have a plan to do the same in suprachoroidal. On the safety side, just as Curran mentioned, we feel very good about the safety package that we'll have for subretinal and suprachoroidal. And that's because we've intentionally selected routes of administration for ABBV-RGX-314 that are compartmentalized and that decrease the risk of the types of safety findings, specifically inflammation that have really hounded other routes of administration like intravitreal. So we feel very well set up not only in our rare programs but also in the common retina indications that we're looking at when it comes to safety.

And Annabel, to come back to the question on genetic screening, we were working closely with the MPS Society and with Duchenne advocacy groups on newborn screening, and their approach largely is at a state level to advance and increase the number of states that provide that. So I think it would be ideal if all entities were working together in concert on that, but that doesn't mean that if one group is not supporting it, the others won't be able to fill that gap and move forward. So we see that as a priority in rare disease, and it's something we'll work with the advocacy groups to support.

Okay. And if I can just ask one quick follow-up to be clear on the last question about ASGCT. You will not be presenting functional data there, correct? I understood it to be a press release within the next six weeks?

Yes. Yeah, it will not be at ASGCT, so no need to book your flight. We'll definitely likely provide that as a press release in the near term.

Thank you. Our next question comes from Alec Stranahan with Bank of America. Your line is open.

Hey, guys. Thanks for taking our questions. This is Matthew on for Alec. Maybe just double-clicking on a previous point. Has there been any change in baseline characteristics, patient age, etc., that you've seen for the DMD trial? And then maybe second, what's the percentage purity for your preps that you're comfortable with or looking for sort of as you're moving forward with manufacturing?

Yes, we will be presenting at ASGCT with a focus on the CMC process, which will provide detailed insights. We're proud of the product, which has a purity level of 80% or higher. Additionally, we maintain high consistency between batches, an area where others have faced challenges. Regarding the enrollment of the pivotal study, we are satisfied with the current enrollment pace and the diversity in patient ages. Looking ahead, we anticipate having a well-distributed number of patients across different age groups to support a comprehensive label when we file.

Thank you. Our next question comes from Luca Issi with RBC Capital Markets. Your line is open.

Great. Hi, team. This is Shelby on for Luca, and thanks for taking the question. Maybe on wet AMD subretinal, you've shown recently that the fellow eye can be treated safely, confirming that the eye is somewhat immune privileged. Are you planning on filing that data? And is your initial label going to reflect bilateral dosing? Any color there much appreciated. Thanks.

Hi, Shelby. Nice to see you. Steve is part of the joint development committee that plans sort of the strategy around the filings, maybe he can comment on that question.

Sure. Hi, Shelby. Great question. This is actually something that we prospectively addressed even as early as our end of Phase II meeting because it's very relevant in wet AMD, where most patients do have bilateral disease. So it would be very advantageous if both eyes ultimately could be treated. And we again always saw that our safer routes of administration, where you would expect less immune response, would be more amenable to being able to treat both eyes. And that's why we prospectively address this explicitly with the FDA, and that's what led to our fellow eye study. And as you mentioned, we're seeing that we're in a good position as far as fellow eye. So yes, I confirm that that's certainly our intent, that this is certainly part of any package that would go in, that would inform clinicians on being able to treat both eyes.

Thank you. Our next question comes from Paul Choi with Goldman Sachs. Your line is open.

Hi. Thank you. Good afternoon, and thanks for taking our questions. I want to ask first about RGX-121 and your expectations for the acceptance of your BLA. Are you also considering the possibility of an Advisory Committee meeting, given that this could be the first approved gene therapy for this condition? Also, regarding the RGX-202 Duchenne Phase I/II functional data update that you mentioned earlier, can you comment on how many patients we expect to follow up with and how current the data might be for that upcoming functional update? Thank you.

Sure, I can address the first question about the Advisory Committee. We are preparing as if we will need one from our internal perspective, with a team focused on being ready if it's requested. We haven't received a final answer from the FDA regarding its necessity yet. Initial discussions suggest it may not be required, but we're awaiting confirmation during the review process. Nonetheless, we will be prepared in advance if one is necessary. Regarding RGX-202, we are planning to expand the dataset to include four or possibly five patients dosed at DL2 as part of the upcoming functional update. Not all patients may have data extending to 12 months, but at a minimum, they would be followed for nine months. We are currently working on compiling the data and are eager to share the update before the first half of the year.

Thank you. Our next question comes from Brian Skorney with Baird. Your line is open.

Hi. This is Luke on for Brian. Thanks for the question. Sorry, if this was already asked, but on the RGX-202 commercial build-out, has the team set a goal for the quantity of product that you expect to be available by the time of a potential launch?

It's a great question. We're actually going through that process of review now as we evaluate our commercial strategy in total. I would just remind you that, in the course of one year, we can produce 2,500 doses. And so we'll come to a point as we get closer to review of the BLA to talk a little bit more about how many doses we would have at launch. We would certainly want to be in a position to quickly address the prevalent market with a significant number of doses. We would estimate the prevalent market could be, in the ambulatory side of the market, something in the order of 5,000 to 7,000 patients, and we would want to be prepared to quickly be able to address that market. So we'll get more specific on number of doses available at launch, but we're in a unique position to be able to build a significant amount of inventory ahead of 2027.

Thank you. Our next question comes from Sean McCutcheon with Raymond James. Your line is open.

Hey, guys. Thanks for taking the question. Just to build on wet AMD, can you provide some detail on how you're thinking about the suprachoroidal opportunity? Obviously, we're looking forward to the start of the NPDR Phase III, but I think we're all curious on the dose necessary to move forward in wet AMD and how you're thinking about that value proposition on the heels of subretinal. Thanks.

Hi. I think I'll let Steve answer that question.

Sure. So this is obviously a massive market. So if you look at the retina space driven by the anti-VEGF target mechanism and treatments thereof, we're at $18 billion and continuing to grow. So I think there's a lot of opportunity across the VEGF driven retinopathies. We and AbbVie are advancing as we were just saying on the subretinal global program or wet AMD. So we're obviously excited about suprachoroidal delivery for that indication. We do see increased optionality and opportunities with the one-time in-office suprachoroidal, and that's why we both are advancing in that space. I think, DR, in particular, is compelling when you consider the reality that patients with non-proliferative diabetic retinopathy who have not developed the site-threatening complications like DME and like proliferative disease, that these patients really are going to need an in-office one-time treatment option that even if you have greater durability agents, if you're going to need repeat injections indefinitely for the rest of your life, that's not going to be a very compelling opportunity. So that's why we and AbbVie are so excited about the opportunity of a one-time in-office treatment to really address that unmet need of DR.

Our next question comes from Yi Chen with H.C. Wainwright & Company. Your line is open.

Hi, good afternoon. This is Eduardo standing in for Yi. I wanted to ask if you have any insights on the recent announcement regarding potential pricing on branded drugs. Do you think this will significantly affect your pricing strategy for gene therapies across these indications?

I think it's too soon to assess the situation. Based on comments from John Crowley at BIO or the Alliance for Regenerative Medicine, the initial impact on cell and gene therapy might be less significant compared to broader branded therapies. It's too early to make any conclusions. From our viewpoint, there’s no immediate effect on our operations, but it's certainly something we need to monitor as we approach an approval.

Thank you. I'm showing no further questions at this time. This does conclude the question-and-answer session, and you may now disconnect. Everyone, enjoy the rest of your day.