Good afternoon, and welcome to the REGENXBIO Fourth Quarter and Full Year 2019 Earnings Conference Call. At this time, all participants are in listen-only mode. Later, we will conduct a question-and-answer session, and instructions will be given at that time. As a reminder, this conference call is being recorded. I would now like to turn the call over to Mr. Patrick Christmas, Senior Vice President and General Counsel for REGENXBIO. You may begin.

Good afternoon and thank you for joining us today. With us are Ken Mills, REGENXBIO's President and Chief Executive Officer; Dr. Steve Pakola, our Chief Medical Officer; and Vit Vasista, our Chief Financial Officer. Earlier this afternoon, REGENXBIO released financial and operating results for the fourth quarter and full year ended December 31, 2019. The press release reporting our financial results 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 in the Management's Discussion and Analysis sections of REGENXBIO's Annual Report on Form 10-K for the full year ended December 31, 2019, which will be filed 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, February 26, 2020 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 purport to project financial positions or operating results of the company. Actual results may differ materially. I would now like to turn the call over to Ken Mills, President and Chief Executive Officer of REGENXBIO.

Thank you, Patrick. Good afternoon, everyone, and thanks for joining us on today's conference call. We will provide a recap of our recent progress advancing and expanding the NAV Technology Platform as well as expected future milestones. Steve, will provide an update of our clinical programs and Vit will provide an update on financial results for the fourth quarter and the full year of 2019. We'll then open the call for questions. So over the course of the past decade, REGENXBIO's mission has remained clear to improve lives through the curative potential of gene therapy based on our proprietary NAV technology platform. We believe single administration gene therapy treatments can significantly alter the course of disease in many patient populations and we are advancing and broadening our pipeline across two treatment modalities, AAV-mediated antibody delivery and AAV-mediated monogenic gene replacement. Both, modalities utilize our NAV Technology Platform to develop potential treatments for those suffering from both rare genetic diseases and potentially expanded treatment options for diseases broadly affecting public health. In 2019, we made great strides broadening our internal gene therapy pipeline and advancing key programs. Last month, we announced updated data for our lead program RGX-314 which is for the treatment of wet age-related macular degeneration six months data from cohort five of our Phase I/II a trial. The data continues to demonstrate meaningful reductions in anti-VEGF burden, as well as improved visual acuity following one-time administration of RGX-314. We remain strongly encouraged by the program's clinical results, and we look forward to reporting longer term data from all cohorts from the Phase I/IIa trial in 2020. Further data regarding the durability and efficacy of RGX-314 will help us plan for the next steps in this program. Beyond RGX-314, we're excited to provide the recent interim data from the…

Thanks, Ken. I’ll begin with our RGX-314 program for the treatment of wet AMD. Last month, we reported six month data for Cohort 5 of the subretinal RGX-134 Phase I/II a dose escalation trial in subjects with wet AMD. Patients continued to demonstrate a meaningful reduction in anti-VEGF treatment burden at six months following administration of RGX-314 with 73% in patients remaining anti-VEGF injection free, while maintaining or improving vision and retinal thickness. We expect to initiate a pivotal program for the subretinal delivery of RGX-314 for the treatment of wet AMD in the second half of 2020. We plan to finalize the design of a trial based on the 12 month assessment of patients and Cohort 5 in the Phase I/II a trial. This will allow us to evaluate further characterization of RGX-314 treated patients, enhancement of the trial design and the potential to accelerate the clinical program. The trial is expected to investigate the one-time administration of RGX-314 at a single dose, compared to anti-VEGF injections which is the current standard of care for patients with wet AMD. Primary efficacy endpoint in the trial will be the mean change in visual acuity from baseline assessed at 12 months after treatment with RGX-314. We intend to submit the design of the trial to the FDA in mid-2020, and begin dosing patients in the second half of 2020. Meanwhile, we continue to plan to initiate clinical trials using SCS Microinjector for the in-office delivery of RGX-314 to the suprachoroidal space. This route of administration could potentially allow for the treatment of an expanded population of patients with wet AMD and DR by providing access to gene therapy treatment in all settings of patient care. We expect to initiate a Phase II trial in wet AMD using the SCS Microinjector in…

Thank you, Steve. REGENXBIO has an extensive footprint in the gene therapy space and our scientific innovation could potentially bring many breakthrough gene therapy treatments to market through our own product candidates, as well as product candidates developed by our licensee network. The technology is currently being applied in one marketed product ZOLGENSMA, more than 20 partnered product candidates, 15 of those partnered product candidates are in active clinical development. Novartis' ZOLGENSMA for the treatment of spinal muscular atrophy, which uses the NAV AAV9 vector has had a strong launch in its first two quarters in the US market, which has provided validation of the NAV Technology platform's utility. Novartis has reported that ZOLGENSMA is currently under regulatory review in Europe with an anticipated regulatory decision in the first quarter of 2020, and also in Japan with an anticipated regulatory decision in the first half of 2020. Our partnerships with groups like Novartis and other cutting-edge gene therapy researchers allow us to invest in programs that we think it ultimately help patients based on the broad applicability of the NAV platform. We are always active and purposeful in developing partnerships with the goal of realizing the potential of NAV Technology in the interest of patients. With that, I'd like to turn the call over to Vit for a review of our financials.

Thank you, Ken. REGENXBIO ended the year on December 31, 2019 with cash, cash equivalents and marketable securities totaling $400 million, compared to $470.6 million as of December 31, 2018. The decrease was primarily attributable to cash used in operating activities during 2019, partially offset by gains on our marketable equity securities of Prevail Therapeutics. Revenues were $11.8 million and $35.2 million for the three months and year-ended December 31, 2019 respectively, compared to $40.8 million and $218.5 million for the same period in 2018. The decreases were primarily attributable to non-recurring revenue recognized in 2018 under our amended license agreement with AveXis for the development and commercialization of treatments for SMA, as well as non-recurring revenue recognized in the fourth quarter of 2018 under our license agreement with Abeona. The decreases in revenue in 2019 partially offset by $10.7 million and $20.8 million of royalty revenue from the net sales of ZOLGENSMA recognized during the fourth quarter and year-end December 31, 2019 respectively. Commercial sales of ZOLGENSMA commenced in the second quarter of 2019 and we are eligible to receive a milestone payment of $80 million from AveXis upon the achievement of $1 billion in cumulative net sales of ZOLGENSMA. Research and development expenses were $33.8 million and $124.2 million for the three months and year ended December 31, 2019 respectively, compared to $24.3 million and $83.9 million for the same period in 2018. The increases were primarily attributable to personal cost as a result of increased headcount, laboratory and facilities cost, clinical trials for our lead product candidates, and externally sourced services for preclinical, regulatory, and manufacturing-related activities. General and administrative expenses were $14.5 million and $51.8 million for the three months and year ended December 31, 2019 respectively, compared to $11.1 million and $36.9 million for the same periods in 2018. The increases were primarily attributable to personnel cost as a result of increased headcount and professional fees for advisory and other services. Net loss was $26.5 million and $94.7 million for the three months and year ended December 31, 2019 respectively, compared to net income of $4.3 million and $99.9 million for the same periods in 2018. Net loss in 2019 includes realized and unrealized gains of $37.8 million recognized during the period related to our marketable securities of Prevail Therapeutics. As of December 31, 2019, we had approximately 37 million common shares outstanding. Based on our current operating plan, we expect the balance in cash, cash equivalents, and marketable securities of $400 million to fund the completion of our internal manufacturing capabilities and clinical advancement of our product candidates into 2022. Sorry to disappoint, but I've given upfront for the year. With that, I will turn the call back to Ken to provide final thoughts.

Thanks, Vit. We are building on strong progress we made in 2019 by broadening our internal gene therapy pipeline and advancing key programs. After more than a decade of steadfast effort and focus, we remain dedicated and committed to improving lives through the curative potential of gene therapy. With that, I would like to open the call for questions. Operator?

[Operator Instructions] Our first question comes from Gena Wang with Barclays. Your line is now open.

Thank you for taking my questions. I have two regarding RGX-314 gene therapy program and then one regarding the IP question. So, for the 314, Ken, you mentioned that Cohort 5 data will help inform you pivotal trial to final design. So what kind of data would change your thoughts on trial design dramatically? And a second question regarding the diabetic retinopathy suprachoroidal Phase 2 initiation in second half this year. Will you wait and do you see the data from the wet AMD suprachoroidal data and at what dose will you start?

Hi, Gena. Thanks for the questions. So, your first one on what will we take from our twelve month data for our five cohorts from the ongoing study. So, I certainly don't foresee anything dramatically changing based on this. But, with this one-time therapy, where we are seeking to have good durability and achieve visual acuity, at least stability and maybe even improvement and also anatomic benefits with decreased injection burden certainly having a full twelve months is very favorable, compared to the six months. So, I think it's really more to - as we said, help enhance and fine tune the design in terms of things like powering, et cetera based on the actual change from baseline values that we see out to twelve months. And also, in wet AMD, that longer duration is also what is generally accepted from a pivotal standpoint. So, actually having real data from wet AMD to patients out to that on which we are basing our final protocol on is very comforting for us. Your second question around suprachoroidal delivery for diabetic retinopathy, we will take advantage of the data that we have from the ongoing subretinal wet AMD study. Yes, it's a different route of administration and even a different VEGF-driven disease. But, we do know anti-VEGF works for all of the, as named VEGF-driven retinopathies, including wet AMD in diabetic retinopathy. So, both from a safety and tolerability, as well as response to anti-VEGF in terms of vascular leakiness, we think that will also help us in terms of the SCS delivery and also for diabetic retinopathy, as well. We have an announcer finalized our plans there including where we would actually start what starting dose we would utilize there. So, again, we'll take full advantage of all of the twelve month data that we have for that.

Thank you. Just one quick follow-up question regarding the IP. I think, could you give us a little bit more color regarding the IP dispute between you and the passage?

Hi Gena. This is Ken. Thanks for that question. We have acknowledged that we sent a letter in sort of the normal course of business related to looking to maintain and protect our intellectual property rights for shareholders to passage, as well as in normal course to other companies that we view may have come into our understanding of using science related to the nanotechnology patents that we have. And the communication that they provided through their SEC disclosure is, I think what we have right now in terms of what that response is. So, if there is been nothing on our part that we viewed was material with respect to providing any more guidance or update. As you know, we have a strong and broad intellectual property portfolio that we take very seriously for the purposes of developing treatments for patients in our own pipeline, as well as licensed to a lot of other companies that are investing in the development of a number of treatments. And we've said for a while that it's our primary interest to be able to enable and support people with licenses, to help achieve the goal of the company for curative potential of gene therapy to reach as many people as possible in those circumstances where we have found that there could be something that would risk that, we are going to take appropriate action. Thanks.

Thank you.

Thank you. Our next question comes from Matthew Harrison with Morgan Stanley. Your line is now open.

Hi, everyone. This is Connor Meehan on for Matthew. So we were also just wondering about the suprachoroidal delivery and I guess how you plan to start the subretinal in Cohort 5 and what maybe the doses are going to look like for that? And if possible, how close you could get to what you've been using thus far?

So, for the Cohort 5 dose, given subretinally that we feel very good about in terms of the subretinal delivery. We think it also gives us a good reference point for thinking of the alternative route suprachoroidal delivery based on preclinical breeching work that we have. So, we do – we are in a position to, I think, think of a narrower dose range than what we needed to use going into, starting our subretinal delivery. So we have the benefit of having learned a lot about response to RGX-314, given subretinally and with our bridging work that will give us some more comfort in terms of where we start. But again, we haven't announced exactly what we are going to – what dose we're going to start with for suprachoroidal.

Got it.

So, we'll give that update later in the first half of this year.

Great. Thanks. And then, just one quickly on 121. I guess, how should investors generally think about what's going to be necessary for approval? And then, I guess, what you guys see is your path forward in terms of registration or just potential registration?

We love the enthusiasm as we've updated just our first data at the end of the year on 121. We do think that we're really encouraged to see changes in biomarkers and have a strong feeling and understanding from our work with the community, both the physicians, the scientists who worked in diseases like MPS II and MPS I of the importance of changes in heparin sulfate and their connection to changes – clinical changes in neuro cog and neurological development in the kids. We just dose escalated though, Connor, and we are continuing to explore the pharmacology in response here. So, I think we've been exploring things in the trial that we think are going to be informative for establishing what the pathway is to getting this treatment to patients as quickly as possible. And both inside and outside of the study will continue that work. We are looking by the second half of this year to have the second cohort fully enrolled in additional data from that first and second dose will put us on a path that we think we'll be able to be more communicative about the specifics of what those next steps are. But it certainly derives from some of the things we've already talked about that biomarkers and the clinical assessments we view as all part of the picture of how a rare disease like MPS II needs to considered in drug development.

Great. Thank you.

Thanks.

Thank you. Our next question comes from Gbola Amusa with Chardan. Your line is now open.

Hi, everyone. Thanks for taking my call. I have three questions on the internal pipeline. I'll start later-stage and go early. First is also on 314 and wet AMD. Since you are heading toward pivotal studies there, can you discuss whether you would see utility in an ex U.S. partner? And whether establishing such a partnership makes sense before after you run the pivotals? Second is on MPS II and RGX-121. And I'll ask maybe the similar question, but in a different way. We saw the data world and you have biomarker data. Can you talk about how at this point, based on natural history studies or whatever we have we can interpret the potential for future clinically meaningful outcomes there? And then, the third question is on the neuromuscular product that you announced. Is that decision to pursue neuromuscular more a function of improved or differentiated science you are exploring or function of potential manufacturing constraints elsewhere? And obviously, it's not mutually exclusive?

Yes. I think sort of back to front, Gbola, I mean, we take pretty seriously when we get to a point, Olivier and the team, along with our technical operations group, and Curran and Steve about deciding to move into new areas of science and ultimately development for treatment candidates. And it means, we have to see benefit and have to feel like we can support development and commercialization in the case of neuromuscular disease, which involves, from our view, an approach that is requiring high quantity of virus in many cases for treatment, as well as a good understanding of the biology of advantages for targeting muscle with different AAVs. This is only we've been looking at for a while and feel quite strongly that the AAV vector has some really special properties that we think are important for advancing treatments in that area and that certainly from a manufacturing perspective having an understanding of a process, quality and scale that can take you into some of these market spaces is important and the clinical team is highly supportive as well as we've been doing work in the background about how we can execute in the development of this in these disease areas. So, we're excited to expand into an area like this. We understand how meaningful it is. And also understand that we need to be prepared for it, which we feel like we are with science, plan and capabilities. On MPS-121, that's a great question. I think the area of, endpoint assessment in rare diseases, even when you're talking about deterministic measures like biomarkers, which are great to have but aren't available in all rare diseases, is always a complicated one. I don't think that I've often sound in our work with experts in the field, scientists,…

Yes. So, certainly we are by design and ready to move forward and advance a full Phase 3 program. We have the internal expertise to move forward in that way and we'll be ready to expand ex-US, as well. So certainly, that's our default. But I'd leave it to Ken in terms of any strategic considerations.

I think, I support Steve and our approach here is, Gbola, we feel like we have the capabilities to take this program into the next phases of development and continue to explore it and set it up for what the next steps are in terms of achieving success. And we are also always open and aware of that if we did have any sort of gaps or deficiencies in our capabilities. We would look to augment that. But we have a great team and we are ready to go.

Great. Thank you both.

Thanks.

Operator, Thank you. And our next question comes from Mani Foroohar with SVB Leerink. Your line is now open.

Hey, guys. Thanks for taking my question. I do not have three questions and a series of follow-ups. So, I stick with a quick suprachoroidal question. So, the level of immune privilege in the subretinal state, obviously the tremendous advantage for you guys in that approach. I think the bio is a little less clear in terms of immune privilege between suprachoroidal versus subretinal. How do you guys think about as you move forward to suprachoroidal approach to the influence whether or not steroid eye drops systemic or topical steroids are relevant? And as a follow-up, would you consider limiting future calls to one question per person?

Especially when you are last in the queue, I respect that Mani.

So, on your prior question to that one, Mani, yes, it's a great point and certainly one of the great benefits of subretinal delivery is how much we know about that space and delivery and that's why it's become the gold standard, not only because the excellent transduction that you get and the actual excellent protein expression that we've seen from our own program, but also because of the relative immune privilege status of the subretinal space, which has led to the fact of no immune reaction or clinical inflammation that we've seen based on delivery of subretinal RGX-314, just to give one example. You are exactly right that much less is known about the suprachoroidal space when it comes to the immune privileged status or lack thereof. What we do know is from our work and the work that's the joint work between Olivier Danos' group and Peter Campochiaro's work is that, with suprachoroidal delivery, we've seen good transduction without significant inflammation. And that's very different than of course what we know happens with intravitreal injection where, as soon as you get to effective doses, you hand-in-hand get the inflammatory response due to the lack of immune privilege of that space. So, at least based on our work with our particular vector, we seem to have much less of a risk of an inflammatory reaction. Having said that, of course we have to go into the clinic and see what we see there.

As it relates to your second question, Mani, we acknowledge and we'll certainly consider it.

Thanks, guys.

Thanks.

Thank you. And I am showing no further questions in the queue at this time. I'd like to turn the call back to Ken Mills for any closing remarks.

Thanks, operator. And thanks, everyone, for joining us. We look forward to following up with you all and providing further updates as the year goes on and in the near future. Have a great night.

Ladies and gentlemen, thank you for your participation on today’s conference. This does concludes your program. You may now disconnect.