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Sarepta Therapeutics (SRPT 2.69%)
Q4 2019 Earnings Call
Feb 26, 2020, 4:30 p.m. ET

Contents:

  • Prepared Remarks
  • Questions and Answers
  • Call Participants

Prepared Remarks:


Operator

Ladies and gentlemen, thank you for standing by, and welcome to the Sarepta Therapeutics fourth-quarter 2019 earnings call. [Operator instructions] As a reminder, today's program may be recorded. I would now like to introduce your host for today's program, Ian Estepan, senior vice president, chief of staff, and corporate affairs. Please go ahead, sir.

Ian Estepan -- Vice President, Chief of Staff, and Corporate Affairs

Thank you so much, John, and thank you all for joining today's call. Earlier today, we released our financial results for the fourth-quarter and full-year 2019. The press release is available on our website at www.sarepta.com, and our 10-K was filed with the SEC earlier this afternoon. Joining us on the call today are Doug Ingram, Sandy Mahatme, Bo Cumbo, Dr.

Gilmore O'Neill, and Dr. Louise Rodino Klapac. After our formal remarks, we'll open up the call for Q&A. I'd like to note that during this call, we will be making a number of forward-looking statements.

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Please take a moment to review our slide on the webcast which contains our forward-looking statements. These forward-looking statements involve risks and uncertainties, any of which are beyond Sarepta's control. Actual results could materially differ from these forward-looking statements, and any and such risks can materially and adversely affect the business, the results of operations and trading prices for Sarepta's common stock. For a detailed description of applicable risks and uncertainties, we encourage you to review the company's most recent annual report on Form 10-K filed with the Securities and Exchange Commission, as well as the company's other SEC filings.

The company does not undertake any obligation to publicly update its forward-looking statements, including any financial projections provided today based on subsequent events or circumstances. And with that, I'd like to turn the call over to Doug Ingram for our corporate update.

Doug Ingram -- President and Chief Executive Officer

Thank you, Ian. Good afternoon, and thank you all for joining Sarepta Therapeutics fourth-quarter 2019 conference call. In 2018, we defined our vision to become one of the world's leaders in precision genetic medicine to treat rare disease, founded both on our precise and efficient RNA platform and on the build of a gene therapy engine capable of rapidly advancing multiple constructs through development into the patient community. In 2019, we executed, further matured and brought that vision into greater focus.

And in 2020 -- through 2020 we will, if successful, realize much of that vision. We have an enormous number of milestones in 2020. But before we discuss them, let us review the progress that we have made in 2019. I will begin with our RNA platform.

As we announced at the J.P. Morgan conference in January, our fourth-quarter 2019 revenue stands at $100 million. In our third full year since launch, our 2019 revenue was $381 million, a 26% increase over prior year. I will remind you that we have never taken a price increase since launch, so our growth comes from continuing to serve the Duchenne community.

Our 2020 guidance for Exondys is $420 million to $430 million. As we are just launching Vyondys, we will wait until later this year before providing revenue guidance, but you can expect the launch curve similar to that of Exondys. In the fourth quarter, we obtained FDA approval for our second RNA therapy, Vyondys 53. The approval of Vyondys was a win for objective evidence-based decision-making.

It was a win for hard-working professionals at the FDA neurology division that was responsible for this review, and most importantly, it was a win for exon 53 amenable patients. With regulatory pathway reconfirmed, we submitted our rolling NDA for casimersen, having announced positive results earlier in 2019. Assuming casimersen is approved, we will have three therapies capable of treating approximately 30% of the Duchenne community in the United States. We will have doubled the number of patients who may benefit from our PMO technology versus Exondys alone, and we will be among the exceedingly small number of biotechnology companies who have internally discovered, developed and brought to the patient community three or more medicines.

In 2019, we commenced our multi-ascending dose study for our next-generation PMO technology, the peptide-conjugated PMO or PPMO for short. Now, let's move on to our gene therapy engine. There, we've made great progress in 2019 as well. Starting with SRP-9001, our gene therapy for the treatment of Duchenne muscular dystrophy using our microdystrophin construct.

We have completed all dosing in what became a 41-patient, placebo-controlled trial, Study 102. Patients are now crossing over at the end of their 48-week period. By now, between our first proof of concept study, our main study for 102 and our crossover, we have dosed more than 30 Duchenne boys with active gene therapy. The study continues uninterrupted, and the last patient last visit should occur in December of this year.

We have designed our next placebo-controlled trial using our commercial process material, and we've taken initial feedback from the agency. This trial which we call Study 301 is designed as a global placebo-controlled, multi-center trial. We have made significant progress on manufacturing. With our partners Thermo Fisher and Catalent, we have built significant capacity with a dedicated facility completed in Lexington, Massachusetts and even greater capacity than that built at Catalent.

Our hybrid manufacturing approach is taking shape with ADPD expertise at our Columbus site and a dedicated ADPD site in Burlington, Massachusetts. This intellectual hub has been responsible for some of our most meaningful advances in 2019. Consider that we have now achieved at scale, commercially viable yields for SRP-9001, we announced at J.P. Morgan that we had commenced engineering runs.

By now, I can tell you that we have commenced our GMP runs for SRP-9001, and we're making great progress on assay development as well. We've made great progress on our limb-girdle pipeline in 2019. To remind you, LGMD, or limb-girdle muscular dystrophy, is an umbrella name for a collection of serious, often fatal neuromuscular diseases. None of these diseases have available therapies, so the opportunity to bring a better life for these patients is compelling.

In the first quarter of 2019, we exercised our option and acquired Myonexus, gaining access to its five LGMD programs. And then we later entered into a license option with NCH to gain access to Dr. Zarife Sahenk's LGMD candidate for LGMD2A. These six programs together have the potential of providing treatments for over 70% of patients with LGMD.

In the first quarter of 2019, we presented expression and safety data from our first three patient proof of concept cohort for LGMD2E, and it was impressive. Expression was 50% on IHC and 30% -- 37% abnormal on Western blot. We came back in the fourth quarter, and we updated with nine-month functional data, indicating that every child was improving on every functional endpoint. We commenced one additional higher-dose, three-patient cohort in 2019 at a four times higher dose with the goal of making a dose selection in 2020 this year.

Moving on to the rest of our gene therapy engine. 2019 was equally consequential. With our partner Lysogene, we commenced the gene therapy trial for MPS 3A or Sanfilippo Syndrome Type A devastating neurological lysosomal storage disease. We built out our gene therapy center of excellence in Columbus, Ohio.

Our center of excellence is already building new constructs and advancing the science of gene therapy. We entered into 14 transactions in 2019, and we in-licensed or purchased 18 new constructs, bringing the total number of research and development programs to 42 across our two platforms. And we have employed a clever incubation strategy that allows us to build an enormously large pipeline while still permitting us to remain laser-focused on our near-term objectives and milestones. And of course, we entered into a transformational alliance with Roche in the fourth quarter of 2019 where Roche will take SRP-9001 to patients outside the United States.

This alliance, by far, the largest ex-US single candidate, license and biopharmaceutical history, validates our approach, our progress and the value of our program, but it also serves our mission. If SRP-9001 proves successful, Roche, with its very impressive ex-US resources and international expertise, will bring our therapy to far more patients far faster than we could have ever done on our own. And it places us in an enviable position with the resources to drive our vision and to execute our plans. With the close of our alliance this quarter, we have well over $2 billion of cash on our balance sheet today, add to that the fact that we have just entered into an agreement to sell our Vyondys priority review voucher for $111 million, add again to that our revenue this year for Exondys and Vyondys, and it should become clear that we are well positioned with the resources, the assets and the talent to drive our ambitious strategy to fruition.

Looking forward, you will see that 2020 is dense with milestones. So, starting with our gene therapy portfolio for 2020, with respect to SRP-9001, we will continue to execute Study 102 with our 48-week last patient last visit in December of this year. We will unblind, evaluate and release those results which should occur in the first quarter of 2021. We are preparing to commence our commercial supply trial, Study 301.

Broadly, we have three work streams for Study 301. We must complete site initiation and training. We must complete our assay work, our engineering work and our GMP runs. And if all goes well, we should have GMP material released this July.

We need to work with the division to obtain their concurrence on the commencement of Study 301. So, of course, there's a lot to do here, but the team is making exceptional progress to date. With respect to our LGMD pipeline, we have dosed all three patients now in our high-dose cohort for LGMD2E. We will have expression and safety results available in the second quarter, and we anticipate announcing that data at an appropriate medical meeting in the second quarter.

We will make a formal dose selection decision in the third quarter. We will complete the assay and process development work for LGMD2E with the goal of having GMP material available in time to commence a trial in early 2021. We will also begin the ADPD work for other of our LGMD constructs as well. We will continue our dialogue with the FDA and come to a view on the development and regulatory pathway for LGMD2E.

And then the remainder of the LGMD pipeline, our goal is to have all of that completed by year-end, so we could commence a trial with commercial process material early next year. We've also dosed 17 patients on our MPS 3A gene therapy program and intend to complete all the dosing by the middle of the year. Our collaborator on CMT, otherwise known as Charcot-Marie-Tooth, Dr. Zarife Sahenk at Nationwide Children's Hospital, had intended to commence our proof of concept study for CMT last year but did not have NCH released material, enabling her to do that.

That material should be available this year, and Dr. Sahenk intends to commence that study in 2020. In addition to our gene therapy center of excellence in Columbus, Ohio, we are also building a separate gene-editing innovation center under the guidance of Dr. Charlie Gersbach of Duke University in Durham, North Carolina and should have that largely complete this year.

We have also significant milestones for our RNA platform this year. We should complete our rolling submission for casimersen in the second quarter of 2020. We plan to result -- to release the results from our PROMOVI study at the MDA Scientific Conference in March. These results from patients that met the enrollment criteria for 201/202, that's the study which formed the basis for the eteplirsen approval, are consistent with the 201/202 data set.

And we will have dosing and safety insight on our next-generation RNA platform, the PPMO this year as well. If the PPMO is successful, it could be a significant advancement in our RNA technology and platform. In summary, we have an enormous amount of work to do this year. But that work will be profoundly consequential for Sarepta and, of course, more importantly, for the patients that we serve.

To those who may say our plans are ambitious, I would agree. But they are not driven by hubris. They are formed instead by the binding conviction founded on objective evidence that the science of genetic medicine has come of age, that a revolution in healthcare is upon us now, and that Sarepta is playing a leading role in translating that science to practical therapies that improve countless lives otherwise stolen by serious, rare genetic diseases. And it is in that spirit that I would invite you to join Sarepta and rare disease patients in the US and around the world in recognizing Rare Disease Day this Saturday, February 29, as we continue to bring awareness about rare diseases and the work that remains to bring therapies to patients fighting those diseases every day.

And with that, I will turn the call over to Sandy to provide an update on the financials. Sandy?

Sandy Mahatme -- Executive Vice President, Chief Financial Officer, and Chief Business Officer

Thanks, Doug. Good afternoon, everyone. Over the course of 2019, we advanced the business in several significant ways. We beat revenue guidance for Exondys 51, launched another of our RNA medicines, Vyondys 53, significantly bolstered our financial position, and struck several new licensing deals, bringing our total number of development programs up to 42.

We also started a partnership with Roche that closed earlier this month and that brought in $1.15 billion into the company. This collaboration brings significant capital to fully fund our pipeline, including our sharing payments, and it provides us access to Roche's significant expertise and greatly expand the global opportunity for our lead gene therapy program, SRP-9001. Now, moving to the financials. This afternoon's press release provided details for the fourth quarter of 2019 on a non-GAAP basis, as well as a GAAP basis.

The press release is available on Sarepta's websites. Please refer to it for full reconciliation of GAAP to non-GAAP. Net product revenue for the fourth quarter of 2019 was $100.1 million compared to $84.4 million for the same period of 2018. The increase primarily reflects higher demand for Exondys 51.

On a GAAP basis, the company reported a net loss of 235.7 million and 140.9 million or $3.16 and $2.05, for basic and diluted shares for the fourth quarter of 2019 and '18, respectively. We reported a non-GAAP net loss of 116.9 million or $1.57 per basic and diluted share in the fourth quarter of 2019 compared to a non-GAAP net loss of 58.7 million or $0.85 per basic and diluted shares in the fourth quarter of 2018. In the last quarter of 2019, we recorded approximately $15.6 million in cost of sales compared to 13.1 million in the same period of last year. The increase was driven by royalties due to Biomarin Pharmaceuticals and University of Western Australia, as well as higher production costs as a result of increasing demand for Exondys 51.

On a GAAP basis, we recorded 223.1 million and $146.2 million in R&D expenses for the fourth quarter of 2019 and 2018, respectively which is a year-over-year increase of 76.9 million. This increase is primarily related to $40 million of increasing expenses in clinical and manufacturing, a 10.8 million increase in compensation and other personnel expenses, as well as a 10.4 million increase in milestone cadence. On a non-GAAP basis, R&D expenses were $135.4 million for the fourth quarter of 2019 compared to 77 million for the same period in 2018, an increase of $58.4 million. The year-over-year growth in non-GAAP R&D expenses was driven primarily due to a continuing ramp-up of our micro distribution program, our assets program and initiation of certain post-marketing studies for Exondys 51.

Turning to SG&A. On a GAAP basis, we recorded $81.4 million and 64.2 million of expenses in the fourth quarters of 2019 and 2018, respectively, a year-over-year increase of 17.2 million. On a non-GAAP basis, the SG&A expenses were 65.8 million for the fourth quarter of last year compared to 52.9 million for the same period of 2018, an increase of 12.9 million. The year-over-year increase was driven by significant organizational growth and expansion, supporting our commercial launch, as well as 40 therapies in various stages of development across several therapeutic modalities.

On a GAAP basis, we recorded 4.8 million in other expenses for the fourth quarter of 2019 compared to 2.3 million of expenses for the same period of 2018. The unfavorable change is primarily driven by increase in interest expense which is recognized for our new term loans that was received by the company in December of 2019. We had approximately 1.1 billion in cash, cash equivalents and investments as of the end of last year. In addition to the closing of our alliance with Roche this quarter, we have well over 2 billion in cash on our balance sheet today.

With that, I would like to turn the call over to Bo for a commercial update. Bo?

Bo Cumbo -- Executive Vice President and Chief Commercial Officer

Thank you, Sandy. Good afternoon, everyone. Toward our 2019 objectives around execution and our commitment to deliver on our stated goals, I am pleased to report the following on behalf of the organization. We exceeded revenue consensus expectations for both the fourth quarter and the full year of 2019, totaling 100.1 million and 380.8 million, respectively.

As Doug mentioned, our 2020 guidance for Exondys 51 is 420 million to 430 million. In terms of continuing to serve the community, we know that there are additional patients who may benefit from Exondys 51, and we will continue to overcome access and reimbursement challenges to get patients on therapy. Golodirsen, or Vyondys 53, received accelerated approval by the FDA on December 12, 2019. Vyondys 53 treats Duchenne muscular dystrophy patients who are amenable to skipping exon 53.

Acting with urgency and the knowledge that patients were waiting, we launched Vyondys 53 within 24 hours of FDA approval, just as we did with Exondys 51. We submitted all of our compendia, contracting and reporting requirements, and vyondys53.com, a critically important resource for families, went live. While we are leveraging our deep knowledge and expertise of the Exondys 51 launch, it is important to understand that there will be standard procedures and required reimbursement policies associated with launching a new drug with a unique NDC or National Drug Code. Our team is prepared to work through these requirements as we have in the past, and we anticipate a measured and steady launch trajectory for Vyondys 53, resembling the launch curve for Exondys 51.

The only difference is that we are preparing and planning for the amenable exon 53 space to be competitive. In support of our goal to increase access for Vyondys 53, we are pursuing a multi-pronged strategy. Although commercial and state Medicaid plans now have a much better understanding of Duchenne, we are continuing to educate about disease progression and the benefits of treatment. Our goal is to work toward coverage to be all-inclusive regardless of ambulation status, age or gender.

We do expect commercial payers to have medical policies in place faster than Medicaid. We also understand that from our previous launch that the mix of commercial to Medicaid patients will adjust over time, and we believe it will eventually move toward a 50-50 mix or higher for Medicaid. Further, we are continuing to engage with state Medicaid plans regarding the CMS guidance letter on the obligation of state Medicaid to make accelerated approval treatments available to patients. As you know, this is critically important for Duchenne based on the percent of patients covered under Medicaid plans.

While the launch over Christmas holiday did delay some physician and patients seeking treatment during that period of time, we have been receiving star forms from top-tier centers across the US and are working with healthcare providers to ensure they are educated around amendability for skipping exon 53, as this population is different from exon 51 with some exceptions. Epidemiology suggests that Vyondys 53 can serve approximately 8% of the Duchenne community. But we will have to take into consideration that there are a number of patients already enrolled in or being recruited for clinical trials, or have a deletion that would be amenable to exon 51 and, therefore, could already be on Exondys 51. With that said, we continue to have conversations with healthcare providers about the number of patients within their clinics and with payers about the number of patients eligible for treatment under their plan.

We are working with both healthcare providers and payers to get all amenable patients on Vyondys 53 as soon as possible. Our mission to be the global leader in precision-genetic medicine started with Exondys 51 and have continued with the approval and launch of Vyondys 53. We are now preparing for the potential launch of casimersen for patients amenable to skipping exon 45. Behind these important medicines is an industry-leading pipeline of programs, 42 in all, driven by new modalities designed to treat complex rare diseases, including MPS 3A and neuromuscular dystrophy.

Sarepta is working with urgency and is focused on understanding the epidemiology and global prevalence of these diseases. We are continuing to refine our analysis and uncover additional insights while collaborating with top neuromuscular specialists. Each day, we are learning more about these diseases. And with each piece of evidence that we gather, we are able to apply these insights to our disease awareness and patient identification efforts that are already under way.

2019 was a great -- was a year of great accomplishments, not only for the commercial organization but the company overall. Looking to the future, patient care will continue to be our driving force as we translate scientific innovations into medicines designed to improve the lives of patients around the world. And with that, I'll turn the call back over to Doug.

Doug Ingram -- President and Chief Executive Officer

Thank you, Bo, and thank you for Bo and Sandy. With that, let's open the call for questions.

Questions & Answers:


Operator

[Operator instructions] Our first question comes from the line of Ritu Baral from Cowen. Your question, please.

Ritu Baral -- Cowen and Company -- Analyst

Good afternoon. Thanks for taking the questions so early and accommodating the key agenda here in D.C., guys. Appreciate it. Doug, can you let us know when the last patients for gene therapy was dosed? Basically, what is the shortest follow-up period, both for microdystrophin, as well as limb-girdle? And can you talk about the safety profile, especially liver, especially platelets, that you've seen in that time period for both programs?

Doug Ingram -- President and Chief Executive Officer

Well, I can just tell you very broadly that as you sort of backward engineer, we're going to have the -- for the 41-patient study, 102, the last patient last visit will be in December. So, if you work backwards, you'll see that the last patient was right at -- I think it actually might have been the very first weekend in 2020, so that was the first 41 patients dosed. We're continuing on an ongoing basis to those patients on crossover as well. There's a significant number, as I've mentioned to you now.

But in the Study 102, between the proof of concept 101, between the main 41 patient study and between the crossovers, we've dosed over 30 patients with active therapy. We have now dosed six patients with limb-girdle, both the previous dose and now the higher dose in limb-girdle. And of course, a lot of that's blinded, so that we'll all see together both the safety and -- the full safety and efficacy. But broadly speaking, I will say, again, consistent with our preclinical models, we have never seen anything that looks like a complement or reductions in platelet counts below the normal level, so things continue as they were.

Study 102 continues, completely uninterrupted, making great progress there. The exciting thing about 102 is that we'll have last patient in December, and we'll have a readout in the first quarter of 2021. And I will remind you that is a readout, not merely on expression and on safety but also on function using NSA. Thank you for that question.

Operator

Our next question comes from the line of Tazeen Ahmad from Bank of America. Your question, please.

Tazeen Ahmad -- Bank of America Merrill Lynch -- Analyst

Hi, good afternoon guys. Thanks for taking my question. I just want to ask about PPMO. You've talked about data for this year.

Specifically, Doug, what kind of data do you think that we'd be able to see? And can you just narrow the time line for us on what part of the year that would be? And then, I guess, related to that, assuming that this data looks better ultimately than PMO, and that you also do have gene therapy approved, how do you think about the package that you're offering overall to DMD patients? Where would they need to be, let's say, on PPMO and gene therapy potentially?

Doug Ingram -- President and Chief Executive Officer

Thanks for that. I'm really glad you're asking about PPMO because we're very excited. We're excited about our RNA technology. Generally, we're very excited about what PPMO may mean because we don't have the results yet.

I'm going to turn this over briefly to Dr. O'Neill to talk about some of the data that we'll get. I mean we did a couple of broad strokes, so we're targeting the middle of the year. For some data, we're continuing to dose escalate.

Things look great. We might even dose escalate beyond the middle of the year, but we'll have safety and -- safety exposure and dosing information by the middle of the year, and I'll let Dr. O'Neill sort of give you some more detail on that. On the broader question about what the what this might mean for patients if we have both gene therapy and either our current RNA or a next-generation version of our RNA PPMO in the future, that's work that we're doing right now.

I know that there are a lot of investors that have kind of assumed for planning purposes that there would be great cannibalization of the RNA franchise when gene therapy comes. And if it turns out in the end that the gene therapy that we're working on is so profoundly impactful that it alone is meaningful and that it cannibalizes it, then so be it. We'll be thrilled with that answer for patients. But I think there is a lot of hypotheses and some thesis and some literature, actually, that would support the conclusion that there may be a commentative value of gene therapy and RNA.

And I think with the PPMO, if it really was a profoundly significant advancement over our current technology, it might make that even more meaningful, so we're doing a bunch of work on that right now. We'll come back likely early next year and provide additional insight and views on what the combination of our RNA technology gene therapy might mean. And there's two things to look at. There's science, obviously, the science of that, and of course, there's the access in reimbursement-related issues that Bo and his team are working on.

And with that, I will turn it over to Dr. O'Neill to talk a bit about the information that we'll receive around the middle of this year.

Gilmore ONeill -- Chief Medical Officer andSenior Vice President

Thanks very much, Doug, and Tazeen, thanks for your question. What we actually are looking at is a combined data set in the second quarter from both healthy volunteers which was a single-ascending dose study and a [Inaudible] multi-ascending dose study in Duchenne patients in which we will have a comprehensive safety data. We will have systemic exposure. That's blood exposure.

We will actually have muscle exposure using muscle biopsy, and we will actually also be looking at some of the timing data with the particular folks on exon skipping because these will be short follow-ups at this point.

Operator

Thank you. Our next question comes from the line of Joel Beatty from Citi. Your question, please.

Shawn Egan -- Citi -- Analyst

Hi. This is Shawn Egan calling in for Joel. On the DMD gene therapy, I know that you guys have previously said that you plan to have adequate supply to address the market. But in a scenario where supply is limited, are there conditions in the agreement with Roche that dictate how product will be allocated between the US and rest of world?

Doug Ingram -- President and Chief Executive Officer

The short answer is we'll -- again, we are trying to achieve our goal. And our goal is to ensure, at the moment of launch and the availability to the community in each of the various regions, that we -- and then in the US and then Roche with us outside the US will go, that we'll have adequate supply for patients. Obviously, we've got much work to do with Roche on that, particularly as we think about how broad this could be outside of the US when you have a partner with the resources of Roche. And we'll just plan for that.

The real work on -- the most significant work at least for us now is on the assay development and process development in getting GMP runs, in getting buy-in from the agency and commencing this trial. We've built already a significant amount of capacity. We've got a stand-alone site at Lexington, Massachusetts. We've got significantly more already over at Paragon count.

And as we do the work and we progress, if we need more capacity still, we can certainly do that. We've got a relationship with Paragon alone that would provide us with the ability to take additional suites and add additional capacity as we proceed, so we're planning for success. And I'm quite confident in our relationship with Roche. We'll both be planning for success.

Operator

Thank you. Our next question comes from the line of Christopher Marai from Nomura. Your question, please.

Christopher Marai -- Nomura Instinet -- Analyst

One on MPS 3A and your progress there. I was wondering, given equipment rebuild, if you could comment a little bit on the age of the patients that are being enrolled. And then perhaps a little bit on the type of endpoints you're going to be looking at and then your confidence in being able to see a difference between -- I believe that's the natural history that there's [Inaudible], and that's it.

Sandy Mahatme -- Executive Vice President, Chief Financial Officer, and Chief Business Officer

Chris, thank you for your question. So, I think there were two elements you want to know about. outcomes and the age of the patients. The study -- and actually, you can see it on clinicaltrials.gov actually requires patients to have at least an age of six months.

But the key ceiling for age is really created by a requirement that they have a development quotient of 50% or greater, so that naturally restricts the upper age group there. With regard to the outcome measure, I kind of hinted which is the development quotient is the primary outcome measure. And essentially, that is a way of capturing the common behavioral development of the children in this trial. And that quotient essentially is, not surprisingly, a ratio determined by the outcome measured in one of two measures, the daily scale which is a development measure, for instance, and toddlers for the assessment battery.

Each one is used depending on the age of the patient. And then to your point, yes, we are looking at the outcome versus a natural history which is, again, described in clinicaltrials.gov. Thanks for your question.

Operator

Thank you. Our next question comes from the line of Brian Abrahams from RBC Capital Markets. Your question, please.

Bert Kinsey -- RBC Capital Markets -- Analyst

Hi. It's Bert on for Brian. I was just interested to get your thoughts on Pfizer's Phase III study design and timing and see, I guess, where you think -- how much of a lead do you think you have at this point in DMD. And then, after your initial feedback from the FDA on Study 3, have there been any changes to your plan to approach the agency with the 12-month functional data from Study 2, with the three-month expression data from Study 3, presumably in early 2021 to determine the potential for that making up sufficient in filing data sets?

Doug Ingram -- President and Chief Executive Officer

Yeah. So, a couple of thoughts. First, on the latter side, there's nothing in our discussions with the agency that have impacted our broad perspective on the approach, both the 301 and our current Study 102. Obviously, we've taken views of the agency, the consideration it made, modifications that they've been modest to date.

Going back to the Pfizer posting on clinicaltrials.gov, I'm going to turn this over briefly to Dr. O'Neill who can provide insight into that. Broadly speaking, I will say, of course, that anybody working in this area of Duchenne muscular dystrophy, kudos. This is, of course, an important area, and all of us working and driving in this direction is a positive.

You can imagine our views on our own construct and its value particularly given the results that we've seen so far, both in safety and in expression. We've got enormous expression, as you've seen in the first four patients dosed with our current dosing. And from a functional perspective, I think you've seen all four of those boys at nine months showed significant improvement, an improvement over natural history at every single functional endpoint, so we're very excited about where we are and where we're driving. And certainly, we see ourselves as the leader in Duchenne muscular dystrophy and the leader of gene therapy for Duchenne muscular dystrophy.

But kudos to anyone working in this area. But with that said, I would turn this over to Dr. O'Neill to give you a view on the submission.

Gilmore ONeill -- Chief Medical Officer andSenior Vice President

Thank you, Doug. Thank you, Bert. As a group of people who are passionately committed to Duchenne boys and helping them take on this disease, we're obviously always very happy to see the increasing investment and increasing attention of the scientific community and frankly, the commercial sponsor community in treating Duchenne. I think what's important to say is that we are on track with all activities with regard to clinical trial site and setup.

We have very excited investigators, very enthused investigators, and patients are very happy about the progress and the commitment that we are receiving. I think it's also important to see that as our program has involved, we're seeing some emerging and differentiation factors, some of which I will name about 4. One, obviously, is our promoter in which we have a specific promoter which is both highly efficient and very precise in targeting expression of microdystrophin. And why does that matter? Because it targets that expression to increase the cardiac muscle which are the two critical organs or tissues adversely impacted by Duchenne.

And second, as Doug has said, we have seen high degrees of expression of microdystrophin in muscle-increased Duchenne boys in our proof of concept study. Three, we have not seen counter-activation. And four, and very importantly, with regard to our program, we have fully enrolled 41 patients, double-blind, randomized placebo-controlled study. And we are on track to actually read out of its evaluation of the clinical benefit of microdystrophin expression in Duchenne boys in the first quarter of next year.

Thanks very much.

Operator

Our next question comes from the line of Alethia Young from Cantor Fitzgerald. Your question, please.

Alethia Young -- Cantor Fitzgerald -- Analyst

Hey, guys. Thanks for taking my question. I guess I just wanted to ask a little bit about upcoming limb-girdle readout. I mean obviously, you got a pretty good -- a quite good response on the low dose of about 50% expression.

I mean is that, do you think, sufficient, or if you're able to see more, would you potentially go into the higher dose? Just kind of help us think about where the plans forward with that.

Doug Ingram -- President and Chief Executive Officer

Yeah, it's a great question. So, again, just to remind everyone, we had -- we dosed three patients in our first dose last year, and we saw a couple of things. One, the therapy was well tolerated with some elevated liver enzymes. I think, and I guess, everyone by now would see that the babies are going to see elevated liver enzymes.

The good news is both in our microdystrophin program and in this limb-girdle program, elevated liver enzymes have responded well to steroids and are manageable, would come back down to baseline. And then from an expression perspective, in our first dose cohort, I mentioned in my prepared remarks, we saw on immunohistochemistry about 51% protein-positive fibers. Very good intensity which is an important thing to consider. Whenever anyone looks at protein-positive fibers, you should always be asking about intensity as well.

I think the intensity here was, if memory is correct, something like 47%. Someone tell me if I'm incorrect. No one's telling me I'm incorrect. And then we saw in Western blot about 37% of normal.

And then on top of that, as you know, we had nine-month functional data from these three children. And the good news is every child and every functional measure was improving. And so, what are we doing now? We're doing one dose higher, four times that dose, so we can make a dose decision between those two. And we are, I think, in a very good position right now.

Because from our perspective, from what we've seen, both in animal models and the like, the dose -- the expression that we're getting right now and the signals that we're getting right now are sufficient to envision that we have a very transformative therapy for limb-girdle Type 2E, and so we wanted to explore one dose higher. If we -- and then when we're heading to dose decision, it's going to obviously be a risk-benefit analysis. And we're going to look at the benefits and we're going to see -- if we see significantly increased expressions with the same safety profile, let's imagine that as one scenario, then certainly, we go to a higher dose. If we see about the same expression between the two, then there will be no value to it.

And of course, we're going to have to -- we have to look at tolerability and safety as well. So, the good news is, I think, either decision -- both -- the decisions will be made based on the objective evidence. We'll see that event in the second quarter. We'll make an official decision in the third quarter.

But I think there's no answer that will be a bad one for us. It will just be objectively driven. And more important than us, I think there will be a good decision in either event for patients that are living with and degenerating from limb-girdle Type 2E.

Operator

Thank you. next question comes from the line of Matthew Harrison from Morgan Stanley. Your question, please.

Max Skor -- Morgan Stanley -- Analyst

This is Max Skor on for Matthew Harrison. Regarding the limb-girdle 2E program, could you provide an update on discussions with regulators? Has your view changed at all on a potential accelerated approval pathway?

Doug Ingram -- President and Chief Executive Officer

So we've just started that process. I think we may have mentioned at the J.P. Morgan conference that we've just opened up the dialogue with the agency. We're envisioning that this is going to be a process that's going to take dialogue and education and fairness to the division.

One of the things that makes this study, and this focus on limb-girdle so compelling is that there are no therapies for it. And because there are no therapies for it, it is not characterized as well as, for instance, Duchenne muscular dystrophy, so education is part of this process. So, we've got an ongoing dialogue with the FDA, where we'll share information and we'll dialogue. We'll come to the right development regulatory approach, and we have some time to do that because at the same time, we've got to do the assay development and the process development.

And then we've got to build GMP material. Our goal is to actually have GMP material released by the end of this year. So, we want to complete that discussion before the end of this year, have a regulatory development pathway developed by the end of this year and start a trial by early next year. Our view remains the same which is that for an ultra-rare disease, like limb-girdle 2E, where this is a gene therapy and the gene therapy here intends to insert a gene that codes for the actual native unaltered protein, a structural protein in a monogenic disease, distinguished by the fact that it is a missing protein that is causing degeneration and death in these children, that we should be able, in dialogue with the agency, to come with the agency to an efficient pathway to bring these therapies to these patients as fast as possible and reasonably considered in light of the constraints that come from dealing with a rare, very ultra-rare and heterogeneous disease.

So, it's a long-winded way of saying we have more dialogue with the agency to have, and we'll have a good answer on that by the end of this year.

Operator

Thank you. Our next question comes from the line of Gena Wang from Barclays. Your question, please.

Peter Kim -- Barclays Bank -- Analyst

Peter for Gena Wang. Congratulations on the updated targets.

Doug Ingram -- President and Chief Executive Officer

OK, hey, I'm sorry. I apologize, but we cannot hear you. Apologies for that.

Peter Kim -- Barclays Bank -- Analyst

Can you hear me OK?

Doug Ingram -- President and Chief Executive Officer

Indeed, we can. Yes.

Peter Kim -- Barclays Bank -- Analyst

Hello?

Doug Ingram -- President and Chief Executive Officer

Yeah, we can hear you now. Thank you.

Peter Kim -- Barclays Bank -- Analyst

OK. Great. I guess my question on modeling. I guess how should we think about the impact of the Roche OUS tail on the opex over the next few years? Like, for example, I think your R&D '19 was roughly 560.

Like how much of that is attributed to DMD gene therapy? And how should we think about modeling cost savings based on the cost-sharing payments?

Doug Ingram -- President and Chief Executive Officer

Yeah. So, just to remind -- I'm going to turn this over to Sandy. But just to remind everyone on the call, so that people track, the relationship that we've entered into with Roche has a number of components. We had an upfront payment that was between a fee and a premium-based equity purchase just shy of about $1.2 billion.

We have additional milestone payments along the way, about $1.7 billion, if I'm not mistaken. We have significant mid-teen royalties associated with revenue, ex US, net sales, ex US, upon rolling that out, ex US And then we had cost-sharing. And so, the cost-sharing is that from the execution of the agreement, actually not the closing of the agreement, but from the execution of that agreement, Roche is responsible for half of all of the global expenses for a development program for our microdystrophin program, SRP-9001. And then to the extent, along the way, there was any additional ex US required studies, Roche would be 100% responsible for that.

And so, with that, Sandy, do you want to comment on its impact on the burn rate over the next year?

Sandy Mahatme -- Executive Vice President, Chief Financial Officer, and Chief Business Officer

Yeah. So, thanks for the question. In terms of the burn rate, to put your question, the Roche deal should bring us cost-sharing payments and that will help with the burn rate of about $5, maybe 100 million this year and in the next few years. But aside from that, the Roche deal is primarily about bulking up our finances.

It gives us a significantly longer cash rate because it's almost $1.2. billion that it brings in. In addition to PRB, it also adds another $110 million to our balance sheet. But I don't think there should be a significant enhancement to the modeling, that work that you would be doing, in terms of modeling out the cash spend.

So, just to talk about the cash spend. If you remember, last year, we had almost $300 million of business development deals primarily due to the $170 million we spent on Myonexus. In addition, we had also guided that we will be investing heavily in gene therapy, both in 2019, as well as in 2020. I think we had indicated about 600 to 650 million of spend.

And that's really where the bulk of our spend is, between business development and gene therapy manufacturing. In addition, in anticipation of Ionis approval, I know it's also bulking up our inventory for a potential casimersen approval, this is another area that, from an R&D manufacturing perspective, that we are directing some of our spend. Aside from that, I don't think our core spend should increase dramatically over what you saw in the fourth quarter. And just going back to your question, I don't think the Roche transaction significantly impacts working on modeling aside from the cash runway that we have.

Operator

Our next question comes from the line of Debjit Chattopadhyay from H.C. Wainwright. Your question, please.Debjit D. ChattopadhyayHey, good afternoon.

So, first clarification on the PPMO program, I believe the update will be 12-week biopsy. So, if that's the case, how would you set expectations in terms of the dystrophin expression? And number two, for the limb-girdle program, would you automatically expect a dose-dependent increase in beta-sarcoglycan given that, historically, when we look at the XLMTM program from Audentes, a three times increase in dose did not necessarily translate into more protein, but provided a much better morphology and higher genomes per cell, so that should give more durability. So, just kind of thoughts around what the expectation should be for both the dystrophin in PPMO and the expression, protein expression for limb-girdle muscular dystrophy?

Doug Ingram -- President and Chief Executive Officer

OK. I'm going to give the second question to Louise. But before I do, let me touch briefly on the PPMO results, so you're exactly right. It's 12-week biopsies, and so the expectations on dystrophin shouldn't exist because we're already then going to look for dystrophin at this early stage.

As you may recall, for dystrophin expression for our PMO, it was a 48-week expression before we really started looking to see the expression, so this is early for dystrophin production. We will see exon skipping, so that will be a strong correlate to the kinds of dystrophin that you would see over time as it builds over time. But that's -- and that's fine because the actual value of this update, this real significant kind of go-no-go on PPMO is frankly dose and safety. So, to remind everyone of what the PPMO is about, so our RNA technology has the PMO.

The base PMO has two things about it that has been very laudable. It's precise, and it's safe. It creates exon skipping, and it creates dystrophin. And it's very safe and safe at even -- at high doses.

It has a limitation associated with it. And that limitation is that it's a neutrally charged molecule that it gets into cells passively, and that's a limitation. Our goal with the PPMO is to reduce -- is to remove that limitation by using a positively charged peptide that would -- in interaction with negatively charged proteoglycans and drags the PMO into the cell in greater abundance. Animal models tell us that it works brilliantly, at least in animal models doing that.

And that we get -- if we can get to the right doses, we get very high increases in exon skipping and therefore, in dystrophin production. There are literally, at the right dose, you could get as much as an order of magnitude increase, so real opportunity to be a significant improvement. The one significant question for us is that can we get to those doses, can one actually get to the kinds of doses that we would believe, over time, would develop dystrophin significantly greater than the PMO. And that's what we will have insight into by the middle of this year as we will have safety insight, there's some exposure insight, exon skipping insight.

And we'll have a view on our ability to get to those doses and then we can envision what dystrophin would look like if we looked out a year or so. And with that, I will turn over to Louise to answer some of the questions about the limb-girdle.

Louise Rodino Klapac -- Senior Vice President,Gene Therapy

So I think the question was around would we expect to see a higher expression at this higher dose given the preclinical data. So, based on our nonclinical data, you're right to say that we typically don't see changes in expression, if -- unless you're at a threefold or half-log higher dose. So, in this case, we're at a fourfold higher dose in our high dose cohort. Based on our nonclinical data, we would expect to see higher levels of expression.

Getting back to Doug's point, we see very good levels of expression, 50% in our low dose, and this is already a transformative dose. We would, based on the nonclinical data, expect to see above that. But this will be a decision based on both safety and efficacy in the end, and we'll look at the data collectively. I think to your point about higher doses, since our high dose in limb-girdle is equivalent to micro-dystrophin, we're quite happy with where we would be at.

If you were pushing the dose even higher is where you might end up seeing saturation and you might not see increased levels of expression. So, in the dosing levels that we're on based on nonclinical data, we feel like we're in a very good range to see increased expression.

Operator

Thank you. Our next question comes from the line of Anupam Rama from JP Morgan. Your question, please.

Anupam Rama -- J.P. Morgan -- Analyst

Hey, guys. Thanks so much for taking the question. Just a quick one for me. I guess following on some of the limb-girdle questions, it sounds like we're going to have a pretty good look in 2Q of kind of expression and then safety and other factors.

So, what's that incremental work that needs to be done between the 2Q update and then when we get sort of dose selection?

Doug Ingram -- President and Chief Executive Officer

That's a great question. Not a ton. So, we're going to look at that data, and we'll have it presented in -- at a medical meeting in the second quarter. We just want to make sure that we're thoughtful, that we make sure we've looped in the DSMB in the process and the like.

So, we -- honestly, there's not a ton of work to do from reviewing the data and releasing the data, to the actual dose selection. But we just want to make sure, for technical reasons, that we're -- that we don't overpromise and that we can make a formal dose selection in the third quarter, so not an enormous amount of work.

Operator

Thank you. Our next question comes from the line of Salveen Richter from Goldman Sachs. Your question, please.

Ross Weinreb -- Goldman Sachs -- Analyst

Thanks for taking the question. This is Ross on for Salveen. So, just given the current time lines with Study 102 and 103 and expectations for 102, that last patient in, in December of 2020, do you guys think that you're still in a position to conduct that three-month comparability in, I guess, by year-end or even early 1Q '20? If not, when should we expect that to occur? And then I just have a follow-up on the MPS III study.

Doug Ingram -- President and Chief Executive Officer

Yeah. So, on that, the short answer is yes. We are still progressing well. In fact, this is a -- the Study 301, to remind everyone, is a significant international multi-center trial, so we also believe there's going to be significant demand for that trial.

We'll be recruiting, I think, briskly when that study starts. So, we feel -- right now, we have a lot to do, so it it's always risky predicting the future. But we feel good that we'll be in the position to look at both functional data out of 102 and at the same time, look at, with respect to a subset of 301, an appropriate subset of 301 expression, safety and CMC-related work in early 2021, so we think we're on track.

Gilmore ONeill -- Chief Medical Officer andSenior Vice President

And if I may intervene, just for a second, Doug. I just want to make sure it's quite clear. The last patient into 102, well, has already occurred. We're talking the last patient actually that's into question.

I would actually apply those to last patient in. Essentially, it's the last patient, last visit, for the one-year functional data, just to be sure that I was clear on that.

Doug Ingram -- President and Chief Executive Officer

Yeah. So, 102 was -- the bulk of 102 was all dosed in 2019. As you know, it was a 40-patient study. It is now a 41-patient study.

One patient was dosed in early 2020. That will result in the last patient, last visit in December. We'll be able to compile that information unblinded and have that -- those results in the first quarter of 2021. And at that same time, if we -- if everything goes to plan, we'll also -- we should also have expression, CMC and safety data from a subset of Study 301 which is the commercial material trial.

Operator

Thank you. Our next question comes from the line from Vincent Chen from Bernstein. our question, please.

Vincent Chen -- Sanford C. Bernstein -- Analyst

Great. Thank you very much for taking the question. On the manufacturing process for your DMD gene therapy, what are the major analytical assays that are remaining to be developed or finalized? And one specific question, what is the potency assay that you use, and have regulators indicated it as satisfactory, or is that still being sorted out?

Doug Ingram -- President and Chief Executive Officer

Louise, do you want to touch on that question?

Louise Rodino Klapac -- Senior Vice President,Gene Therapy

Sure. So, all of the release assays have been developed. They're just in the final stages of validation. So, currently, our -- we're using an in-vivo potency assay with an in-vitro potency assay in development.

Operator

Thank you. Our next question comes from the line of Whitney Ijem from Guggenheim. Your question, please.

Whitney Ijem -- Guggenheim Partners -- Analyst

Hey, guys. Just a quick one for me, and sorry if I missed it. But for the MPS 3A program, I think you said 17 patients treated. Can you remind us what the time point for the primary endpoint is and if there are any interims or any potential to get kind of an interim read on that given you have treated a significant number of patients there?

Doug Ingram -- President and Chief Executive Officer

Yeah. So, the current protocol has a -- it's a 20-patient study. Our goal is to have all of the patients dosed before the middle of this year. We're obviously well on the way toward that 17 of 20 already dosed.

It's against the matched natural history cohort. It's a two-year study with a one-year interim, so there is the chance of an interim look at the data in the middle of 2021.

Operator

Thank you. Our next question comes from the line of Joseph Schwartz from SVB Leerink. Your question, please.

Dae Gon -- SVB Leerink -- Analyst

Good afternoon. Thanks for taking our question. This is Dae Gon dialing in for Joe. Just a question and a follow-up, if I may, regarding your PMO filing strategy.

So, with your rolling NDA submission initiated for casimersen, following your golodirsen experience, I was wondering if there is any additional requirements to submit that NDA or any particular commitment on your part, either prior on or after the potential approval. And sorry if I missed this. But can you clarify the guidance for the mission 51 confirmatory trial for eteplirsen? I understand Exondys is due to complete by 2024, but I wanted to get the number for mission 51, please.

Doug Ingram -- President and Chief Executive Officer

So going to the PMO strategy, the short answer is no. We had a very positive, very thorough review from the Neurology Division, at the end of which the Neurology Division firmly recommended the approval of that therapy. And of course, while there was a delay, it was -- it got that approval for us, and so we're going to follow the same pathway for casimersen. We're in the midst of enrolling NDA.

We should have that rolling NDA completed in the second quarter, then we'll have our PDUFA date. We'll be providing updates along the way. With respect to eteplirsen, where there's -- I apologize I missed the exact question. The short answer with eteplirsen, just to remind everyone, is that we have a confirmatory study with respect to eteplirsen.

It really is two studies. It required, first, a healthy human volunteer study. I would remind everyone that this is a bit of an unusual confirmatory trial. But if you imagine the normal confirmatory trial using a placebo control, you would have the current dose approved versus the placebo-controlled.

This is different. This is our current dose versus an escalating higher dose of eteplirsen, to really ask the question if even higher doses of eteplirsen would confer additional benefit over the benefits already achieved with the current dose of eteplirsen. That required -- because that -- those doses were not yet approved, that required, as a predicate, a healthy volunteer study to be conducted to ensure that it was safe. And that was completed and read out, and it was safe and we have commenced study for -- to our mission, and we're on our way with it.

But with a very specific question, then the short answer is we're on our way. It will be -- obviously, it will take some time to complete that study.

Operator

Thank you. Our next question comes from the line of Tim Lugo from William Blair. Your question, please.

Lachlan Hanbury-Brown -- William Blair -- Analyst

Hey. This is Lachlan on for Tim. I was wondering if you could provide an update on the number of patients that have enrolled in the second site for the microdystrophin studies at UCLA and whether you've sort of seen or heard any differences in the experience there compared to dosing in the prior patients at nationwide, especially as it pertains to safety and tolerability.

Doug Ingram -- President and Chief Executive Officer

Sure. The first -- the answer to your first question, first, the bulk of the patients obviously were enrolled and dosed at Nationwide Children's Hospital under Dr. Jerry Mendell as he had the bulk of the patients before we had increased the end of the trial from 24 to 40 and what, became 41, so the bulk of the patients were at nationwide. And answering your second question, the answer is no.

We have heard of no significant differences in experience between the two sites.

Gilmore ONeill -- Chief Medical Officer andSenior Vice President

May I just add that, of course, the blind -- this is a blinded study, so the blind has been maintained. And so, when we talk about the experience, it's the experience at the site level. We can't comment on safety or efficacy experience as those updates remain blind. I was -- sorry, that was Gilmore intervening.

Doug Ingram -- President and Chief Executive Officer

We recognize your accent.

Operator

Thank you. Our next question comes from the line of Liisa Bayko from JMP Securities. Your question, please.

Liisa Bayko -- JMP Securities -- Analyst

Hi. Thanks for taking the question. Doug, you seem a little hesitant on the commercial supply of Study 301. Can you maybe comment, are you tracking, is everything going as planned thus far? And just to clarify, are you expecting GMP product to be available in July, or is that when the study will actually start enrolling? If you could just clarify that.

Doug Ingram -- President and Chief Executive Officer

So look, the short answer is the team is doing brilliantly. I can't give nothing but kudos to our technical operations team and our clinical operations team in progressing toward the commencement of Study 301. They've done great work from a process development and clinical development at site radius, so we're tracking right now. And we will have GMP material released in July.

The precise date that we will commence the trial is predicated on three things. It is certainly predicated on having that material available. That is an enormously significant part of this. And that's why we were so excited to be achieving commercially viable yields by the end of 2019.

And with the fact that we were able to start engineering runs, it was exciting for all of us. The idea that we were able to start GMP runs was exciting for us as well. And of course, we've built an enormous amount of capacity to be ready for that. Then the two other things that we have to do across the way are we have site readiness.

That means we have to go initiated and trained and the like. I think we're well on the way to getting all of that done, and the team is very focused on that. And then the third thing that we're going to have to do as a predicate is to gather the data and engage with the agency and ensure that we're on the same page with the agency to commence the Study 301. So, much to do, but we have made an enormous amount of progress if one stands back for a bit and considers where we were at the beginning of this journey, just 1.5 years or so ago, and we're tracking well for the commencement of 301 and we're tracking well for the completion of Study 102.

Operator

Our next question is a follow-up from the line of Christopher Marai from Nomura Instinet. Your question, please.

Christopher Marai -- Nomura Instinet -- Analyst

Hi. Yeah, thanks for taking the follow up. I was wondering if you could comment perhaps on the Phase III trial and its design for the gene therapy product 9001. I guess Pfizer reported there a trial design or recently announced their trial design on clinicaltrials.gov.

It appears they are dosing patients with their gene therapy, as well as staple doses, steroids, throughout the period of the trial, so it seems to be on top of steroids. And I was wondering if you could comment on your plans for any regulatory discussions in that regard because as I recall, you're not dosing on top of regular steroid doses.

Doug Ingram -- President and Chief Executive Officer

So boys with Duchenne muscular dystrophy are a standard of care on steroids. So, we would maintain, in all of our studies, children on regular steroids throughout the study. We also have a protocol to modestly increase steroids in advance in the treatment as a prophylactic which is typical. So, the Study 301 tracks toward the commencement.

And we've talked about the design before. It hasn't changed in a significant way. It is currently envisioned to be a one to one placebo-controlled trial. And the main Study 301, it's currently envisioned to be four to seven years old.

It will be a multi-center trial as well, obviously blinded. We will have several studies as well along the way. And we're moving as fast as possible, both for them as well. One of those is the study we call 303 which is for a study focused on non-ambulatory patients.

We think it's extraordinarily important to focus as well on non-ambulatory patients. Even though I think there is a strong argument that in the United States, one can't achieve an approval across a broader age group when a mechanism of action would presume that all age groups would benefit even if you study the -- a smaller age group. But both for access and reimbursement purposes in the United States, as well as for approval of ex US, it's important that we study a broad age population, and we'll do that through Study 303, as well as through 301.

Operator

Thank you. This does conclude the question-and-answer session of today's program. I would like to hand the program back to Doug Ingram for any further remarks.

Doug Ingram -- President and Chief Executive Officer

Thank you all for joining us this evening and for your questions. We appreciate them all. And as I think everyone can see, we've made a lot of progress over the last few years toward our broader vision of becoming one of the most significant leaders in genetic medicine, focused both on RNA and the build of this, what we believe, to be a profound gene therapy engine, upon which we are working. 2020 will be an enormously important year for us.

We've got a lot to do here. And if we're successful in doing it, and if science cooperates with us, then we will make an enormous leap toward achieving our vision of bringing a better life to countless patients who are living with, degenerating from and far too often, dying from rare genetic disease, so thank you very much for that. I look forward to the opportunity over the course of 2020 to keep everyone updated as we progress. Thank you.

Operator

[Operator signoff]

Duration: 71 minutes

Call participants:

Ian Estepan -- Vice President, Chief of Staff, and Corporate Affairs

Doug Ingram -- President and Chief Executive Officer

Sandy Mahatme -- Executive Vice President, Chief Financial Officer, and Chief Business Officer

Bo Cumbo -- Executive Vice President and Chief Commercial Officer

Ritu Baral -- Cowen and Company -- Analyst

Tazeen Ahmad -- Bank of America Merrill Lynch -- Analyst

Gilmore ONeill -- Chief Medical Officer andSenior Vice President

Shawn Egan -- Citi -- Analyst

Christopher Marai -- Nomura Instinet -- Analyst

Bert Kinsey -- RBC Capital Markets -- Analyst

Alethia Young -- Cantor Fitzgerald -- Analyst

Max Skor -- Morgan Stanley -- Analyst

Peter Kim -- Barclays Bank -- Analyst

Louise Rodino Klapac -- Senior Vice President,Gene Therapy

Anupam Rama -- J.P. Morgan -- Analyst

Ross Weinreb -- Goldman Sachs -- Analyst

Vincent Chen -- Sanford C. Bernstein -- Analyst

Whitney Ijem -- Guggenheim Partners -- Analyst

Dae Gon -- SVB Leerink -- Analyst

Lachlan Hanbury-Brown -- William Blair -- Analyst

Liisa Bayko -- JMP Securities -- Analyst

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