Erin Cox - Investor Relations Chris Garabedian - President and CEO Sandy Mahatme - SVP and CFO

Christopher Marai - Wedbush Securities Edward Tenthoff - Piper Jaffray William Tanner - Lazard Capital Markets Ritu Baral - Canaccord Genuity Heather Behanna - JMP Securities Brian Skorney - Robert W. Baird Tim Lugo - William Blair Joseph Schwartz - Leerink Swann Reni Benjamin - Burrill Institutional Research Kimberly Lee - Janney Capital Markets Debjit Chattopadhyay - Emerging Growth Equities

Welcome to the Sarepta Therapeutics First Quarter 2013 Earnings Call. My name is Donna, and I will be your operator for today's call. At this time, all participants are in a listen-only mode. Later, we will conduct a question-and-answer session. Please note that this conference is being recorded. I will now turn the call over to Erin Cox. You may begin.

Thank you, Donna, and thank you for joining today's call. Earlier today, we released our financial results for the first quarter of 2013. The press release is available on our website at www.sareptatherapeutics.com and our 10-Q will be filed on or before May 10. Joining me on the call today are Chris Garabedian, our President and Chief Executive Officer; and Sandy Mahatme, our Chief Financial Officer. Please note that we have slides posted in conjunction with the webcast, that supplements some of the information we will be discussing during today's call. These slides can be found on the Investor Relations section of our website. If you're following along, please turn to Slide 2. I would like to note that during this call, we will make a number of statements that are forward-looking, including statements about the safety, efficacy and potential of Sarepta's product candidates, timelines for clinical development activity, the potential and timing for regulatory submissions, and meetings with the FDA; the potential and timing for regulatory filings, review and approval of Sarepta's product candidates, including under Subpart H Accelerated Approval; Sarepta's ability to establish and protect intellectual property rights, Sarepta's timing and ability to scale its manufacturing capabilities, Sarepta's estimates regarding its future revenue, operating loss and expenses, expectations regarding future success and adequacy of financing and reserves on hand. Our ability to obtain continued funding from government and other sources, and our anticipated 2013 financial results. For a detailed description of risks and uncertainties we face, you are encouraged to review the official corporate documents filed with the Securities and Exchange Commission. With that, let me turn the call over to Chris Garabedian, our President and Chief Executive Officer. Chris?

Thank you, Erin. Good morning everyone and thank you for joining us today for our quarterly financial and corporate update for the first quarter of 2013. I will be updating you on our recent business activities, and Sandy Mahatme will review the company's financial results for the first quarter, before we take your questions during the Q&A portion of the call. We have slides that are accompanying the call, and we will be referencing them during this update. As you all know, 2012 was a transformative year for Sarepta, and we had a number of critical activities over the last few months, to keep the company on a critical path towards realizing the full potential of eteplirsen, our lead clinical candidate for Duchenne muscular dystrophy, as well as a broader pipeline of RNA-based therapeutics. If you refer to Slide 3, titled eteplirsen program status, I would like to begin by giving you an update on the activities that we are engaged in, with respect to our work on eteplirsen with the FDA to determine the feasibility of an Accelerated Approval NDA submission. As we disclosed earlier this month, we received meeting minutes from the FDA, summarizing our End of Phase II clinical meeting that occurred in the first quarter. One of our key objectives at this meeting, was to gain feedback on the feasibility of an Accelerated Approval NDA filing, with the existing eteplirsen dataset. As a reminder, the FDA has authority to grant Accelerated Approval, under what is known as Subpart H of Title 21, Part 314 of the code of Federal Regulations. This regulation states that the agency may speed up the approval of a new drug, for a serious and life threatening disease, based on the drugs effect on the surrogate endpoint that is reasonably likely to predict clinical benefit. At this meeting, we asked the agency of our Phase IIb clinical data, which show statistically significant increases in novel dystrophin over 48 weeks, along with supportive clinical outcomes and a good safety profile, could support an Accelerated Approval NDA filing. They did not provide us with a decision on the feasibility of this filing, but they have requested two summary documents from our existing dataset. One that focused on dystrophin as a surrogate endpoint, and one that's focused on a summary of all of our clinical outcomes. They indicated, they would consider the feasibility of an Accelerated Approval filing on our existing dataset, after a review of these documents. We recognize that the context in which the agency evaluates this question, is very important, and that they need to be thoughtful and measured in their approach, before making a decision on a new surrogate marker for a rare disease. Again, to summarize the FDAs response, the agency explicitly stated, that they had not made a determination regarding the acceptability of the proposed Accelerated Approval NDA filing, and that they would consider this additional information and data, before making a final decision. Since we last updated you earlier this month, or last month, we have made good progress, with compiling these summary reports on dystrophin and clinical outcome, and we are continuing this effort with great urgency, and remain on track to submit the reports to the FDA this month. An important aspect of the argument that dystrophin is a surrogate marker, likely to predict clinical benefit, is to support our preclinical and clinical evidence of dystrophin production, it's quality, quantity and function, and link this to our six minute walk test results and other clinical evidence that the patients in our study are not following the natural course of decline for this disease. In a few moments, I will review in part, the perspective we will be sharing with the FDA on the six minute walk test natural history, particularly as it relates to the updated 74-week data, which we will be sharing with the agency for the first time. This analysis was presented a couple of weeks ago at an investment conference, but I believe it's important to highlight this, as it is an important element to understanding eteplirsen's effect on clinical outcomes and the natural course of this disease. In terms of next steps, once we submit the additional information that the FDA requested this month, the FDA will work with us to determine the timing and nature of the follow-up response, as it relates to the feasibility of an Accelerated Approval filing for eteplirsen. At this point, we do not know what form that meeting will take place, or the potential timing, but we are confident that after the FDA receives these documents, we will quickly get from them, their preference, as to how we will address any questions they may have, and the best timing and form of a follow-up meeting. We have been very encouraged by the agency's interest and responsiveness, as it relates to the eteplirsen program, so we are hopeful that we will be able to meet with them by the end of the second quarter, and achieve resolution on next steps, in the weeks thereafter. However, no follow-up meeting has been calendared, and there is no guarantee that this meeting will take place in the second quarter, but we remain hopeful where we sit today. We also continue to advance our manufacturing efforts, and have been preparing briefing documents on our CMC package, and expect an End of Phase II meeting, that focused on CMC issues, chemistry manufacturing and controls with the FDA in the third quarter of this year. We will await a decision from the FDA on the feasibility of Accelerated Approval, prior to formally requesting this meeting, as it will have a different emphasis and scope, depending if it is under the context of an Accelerated Approval filing, or if it would be under a scenario, where a confirmatory study is needed. If we pursued an Accelerated Approval NDA filing, we are interested in discussing with the agencies, our flexibility on issues such as the amount and length of stability data they would need from larger scale batches of eteplirsen, the quality and quantity of comparability data batch to batch, as we scale up to larger production runs, and their needs for process validation, as we apply our process to larger scale production runs. Overall, we have made tremendous progress on moving the eteplirsen program forward, since the beginning of the year, and we continue to work hard to achieve resolution as quickly as possible, on the fastest path to registration. Moving to Slide 4; I'd like to take a few moments to review the updated 74-week six minute walk test data, from our long term, Phase IIb extension study with eteplirsen. I'd also like to give you some of our thoughts on how these data compare with the natural history in DMD in a moment. We first announced the 74-week data in early April, and last month our lead investigator on the study, Dr. Jerry Mendell of Nationwide Children's Hospital, presented these results at the Muscular Dystrophy Association Scientific Conference, which was very well attended by more than 500 treating physicians and allied health professionals. We think the most important takeaway from these updated data, is that we continue to see a stabilization of walking ability, across all eteplirsen treated patients. This observation is particularly interesting in the placebo/delayed treatment cohort, which showed stability on six minute walk test after being on the drug, from the last time point before dystrophin was confirmed in these patients, or beginning at week 36. From week 36 to now, through week 74, we saw walking ability in these patients stabilize, with a less than 10 meter decline over this timeframe. To be clear, this is after the placebo patients have been on drug for 48-weeks, and have now been stable for 38 weeks, from the last time point before dystrophin was confirmed in their muscle biopsies, which were confirmed with statistical significance at week 48, or after 24 weeks on eteplirsen. As a reminder, on this slide, you see an analysis using the maximum scores on the six minute walk test, which was our primary prespecified analysis, and what we've reported most frequently. For this analysis, we took the maximum six minute walk test value, when the test was repeated at clinic visits, when a muscle biopsy was conducted at week -- at baseline, at week 12, week 24, and week 48. Moving on to Slide 5; you see a different analysis using the mean of the repeated test results. As we previously said, we think this and other analyses of the six minute walk test results, such as using minimum scores, or just the day 1 scores, when key measures were taken, confirm and support the robustness of the treatment effect seen in the prespecified analysis. This mean analysis is more appropriate, as we continue to follow the long term stability of these patients, as it reflects a more appropriate baseline six minute walk test value, compared to using the mean of the maximum scores, and comparing to our natural history studies, and we are only collecting one value on six minute walk tests for subsequent visits. So using the maximum score from the baseline is less appropriate for this longitudinal analysis, and again the mean provides a better comparison, versus natural history, from a baseline six minute walk test perspective. So as we look at Slide 6; we have compiled the available six minute walk test data from the largest and most comprehensive natural history of datasets currently available. These include, peer-reviewed articles by doctors Craig McDonald, and separately Elena Mazzone, as well as placebo arm data from the PTC Therapeutic study of Atalauren, which they have presented now at a number of scientific congresses. Together, these data suggest that age and baseline six minute walk test distance are important predictors of ambulatory decline, and we see marked declines on the six minute walk test, from each of these datasets, that we believe are highly consistent with the rate of decline of our placebo cohort through 36 weeks. Especially, when our inclusion criteria limited higher six minute walk test scores, and in essence, excluded the healthiest patients from our study. Importantly, the Mazzone paper suggests that a baseline six minute walk test difference of 330 meters, is an important predictor of a more rapid risk of rapid decline on six minute walk tests, and might be considered as a cut off for excluding patients from clinical studies with ambulatory measures, which I will mention in a moment, further support eteplirsen's effect on stabilizing our placebo cohort. When we look at the Modified Intent-to-Treat cohort that received eteplirsen for a full 74 weeks, we see a striking contrast, versus the natural history, where these patients only experienced a two meter or less than 1% decline in walking ability, after nearly a year and a half of treatment. In addition, when we look at the placebo/delayed treatment arm after week 36, the time point at which we think these patients were likely producing meaningful levels of dystrophin, beyond this point, we see only a nine meter or about a 3% decline through week 74. Note, the mean six minute walk test distance at week 36 in the placebo/delayed treatment cohort, was below the 330 meter cutoff, that the Mazzone paper suggested is a predictor of substantial and rapid decline. On Slide 7; we show individual patient data on the six minute walk test. We are often asked about the variability in the six minute walk test results. So we thought it was important to disclose these data, which we did for the first time last week at an investment conference, and to orient you to the slide, we show in green a less than 10% change, in yellow a 10% to 15% change; and in red, a greater than 15% change. Let me add that Craig McDonald, an expert in natural history of Duchenne, has indicated that a 10% change would be clinically significant, whether it's a decline of ambulation or a reduction of a decline to that degree. As you can see, we generally saw stabilization or a less than 10% decline across the patients in the Modified Intent-to-Treat cohort, from baseline through 74 weeks. One patient in this cohort declined about 13%, but he was the oldest patient in the study overall, with a baseline age of nearly 11 years, and we think it's encouraging that he shows good stabilization, between weeks 36 and 74. In the placebo/delayed treatment cohort, we saw a consistent deterioration of more than 15% across all patients from baseline to week 36. However, all of these patients demonstrated stabilization or a less than 10% decline after week 36 and through week 74. The key takeaway here is that we saw a generally consistent effect across every patient in the study, after dystrophin was confirmed in a robust and a statistically significant manner, and a stabilization that would not be expected, based on the natural course of this disease, based on multiple datasets that have been evaluated. Note that the mean age of both cohorts is now over 10 years at 74 weeks, and close to 11 years at our original eteplirsen treated group, which was about half a year older than the placebo patients. Both of an age, that we would not expect to see this type of stabilization, especially, when you look at their baseline six minute walk test values prior to producing dystrophin. So overall, we think we have strong evidence that this drug, and the dystrophin its producing, is stabilizing clinical function on the six minute walk test, which is the most well studied and characterized clinical outcome measure in DMD, and has been used as the primary endpoint in other studies of dystrophin producing DMD drugs, and has also served as a basis of approval, as a primary or a company-primary endpoint for other rare neuromuscular conditions approved by the FDA. Now I will briefly address the safety results highlighted on Slide 8; as we previously reported, we continue to see a favorable safety profile for eteplirsen, which we recognize as clinically important for a chronic therapy, that may be used throughout the course of a patient's life. Through 74 weeks, there were no serious adverse events and no clinically significant treatment related adverse events. As I have mentioned before, one patient had a transient elevation of urine, on a -- protein area, on a urine dipstick test. However, the elevation resolved within 24 hours, resulted in no-clinical symptoms, and the patient continued treatment uninterrupted. We also observed the transient elevation of urine protein at a patient on placebo, during the first 24 weeks of a similar manner, in this study. Overall, there have been no study discontinuations, withdrawals, or hospitalizations, and all patients continue to receive treatment. Before we move on to our other programs, I want to mention a few additional activities of note, which are highlighted on Slide 9. As we previously noted, our scale of manufacturing plans are on track, and we have begun our efforts to produce eteplirsen at a larger scale, or what we've described as a mid-scale production batches for our confirmatory clinical trial with eteplirsen and development of our follow-on DMD drugs. We now expect to execute on our plans to further scale up to even larger production in the coming months. We view this effort as mission critical to prepare to satisfy the potential commercial demand for eteplirsen, if we choose to pursue an Accelerated Approval NDA submission, and we have made a strategic decision to initiate the beginning of these activities in the coming months. As I said before, we have a lot of expertise and knowhow related to this chemistry, as we have been producing drug supply for our eteplirsen or other drugs for several years in over a decade for other indications, with good stability and purity profiles and good comparability batch-to-batch. While there are always risks in scale up, we continue to be confident in our ability to develop the same drug product at a larger scale. As you know, we are also moving forward with plans to initiate a confirmatory clinical study of eteplirsen later this year, with dosing in patients to begin in the first quarter of 2014. We continue to evaluate potential study designs, that will meet the FDA requirements for an adequate and well controlled trial, and what is in reality, an ultra-rare disease population. We expect to have additional interactions and potential follow-up meetings with the FDA, to specifically discuss the confirmatory study design, and expect meetings to occur throughout the third -- meetings and interactions to occur, throughout the third and fourth quarter, to finalize our study protocol for the confirmatory study. In parallel, we will continue to meet with clinical sites, and contract research organizations, to put in place the plans needed to enroll qualified patients quickly, and initiate the study on schedule. With regard to our broader DMD program, we recently finalized an exclusive worldwide license agreement with the University of Western Australia. The UWA Research Group has done groundbreaking work in DMD, to sequence the dystrophin gene, and they have been key collaborators for us over the years. This new agreement, gives us access and intellectual property to even more of UWA sequence optimization work, and enables us to significantly develop our DMD pipeline, to address even the rarest of exon deletions that we can target in DMD. I want to emphasize here, that this agreement represents a major milestone toward achieving this vision of the broader DMD program, which is to develop a deep pipeline of exon-skipping therapies and address all of the boys and young men, who can benefit from this technology. I also want to note, that our preclinical development activities for our DMD program, addressing exons 45, 50, and 53, remain on track, and we continue to expect to initiate the first clinical studies in patients -- I am sorry, first preclinical studies for these drug candidates this year and next. We also continue to make good progress with our government sponsored infectious disease pipeline programs. We announced earlier this week, that we initiated a multiple ascending dose Phase I study in healthy volunteers, for our drug candidate AVI-7288 for the treatment of the highly lethal Marburg hemorrhagic fever virus. This study will generate important safety data, to move this drug forward towards a potential approval, for use as a countermeasure to a possible bioterrorism threat. We continue to expect to complete this new Phase I study by year end, with initial data available in early 2014. Overall, we are very pleased with our success to date with AVI-7288, which has shown strong antiviral activity, survival and a good safety profile in preclinical and human PK study. This program uses our next generation PMO plus, or positively charged morpholino chemistry, and we think the results demonstrate the versatility of our platform technology, to address serious infectious diseases in the future, and potentially other therapeutic areas as well. I am also pleased to share with you that we announced today, the news that the first patient has been posed in our Phase I study of AVI-7100, our drug candidate for influenza. The Phase I double-blind placebo controlled dose escalating study, will assess the safety, tolerability and pharmacokinetics of single and multiple doses of AVI-7100 in healthy volunteers. This study is being conducted by the NIH, and the NIAID, the National Institute of Allergy and Infectious Diseases division of the NIH, under a clinical trial agreement we executed last year. This clinical trial agreement builds upon the development of AVI-7100 that was previously supported under a contract with the US Department of Defense, which enabled a preclinical development through completion of a first cohort of the Phase I single ascending dose study to provide initial human safety data. As we continue to see regular news reports, highlighting the potential public health impact of a resistant or a more virulent and transmissible flu strain, we believe our drug platform is uniquely positioned to address potential pandemic applications, and we are encouraged with the continued progress with this program. Finally, before I turn over the call to Sandy, to review our first quarter financial results, I'd like to take a few moments to briefly offer my perspective of Sarepta's financial health. As noted in the press release, our cash position remains very strong, with about $175 million on hand of cash or cash equivalents, and invested cash as of March 31. As you can see clearly, we are thoughtfully managing our spend, as we ramp up critical activities, including the scale up of our manufacturing capabilities, preparations for our confirmatory eteplirsen study, and the onboarding of critical new hires across key functional areas. In line with our full year guidance, we continue to expect our cash burn to substantially increase towards the end of this year, as these and other activities reach critical mass. Importantly, all of these efforts continue with pace across clinical, regulatory, and our scale up of manufacturing within the guidance that we shared earlier this year. With that, I am going to conclude my prepared remarks on our corporate update, and turn the call over to Sandy Mahatme, our Chief Financial Officer, to give you a financial update for the first quarter. Sandy?

Thanks Chris. Good morning everyone. Please go ahead and turn to Slide number 10. This morning's press release provided detail for the first quarter of 2013, in both an adjusted or a non-GAAP basis, as well as a GAAP basis. Management believes that non-GAAP results are useful in evaluating the current underlying trends in our operations, and highlight the impact of our operations, on our cash balance, while also providing information relevant in comparing current results, with prior periods. We will be presenting non-GAAP results on this call, primarily, due to the significant non-cash impact that the revaluation our outstanding warrants has on our net results. These results also exclude the impact of stock based compensation and our ongoing corporate relocation to Cambridge. Please refer to our press release for a full reconciliation of GAAP to non-GAAP results. In the first quarter of 2013, we reported an adjusted loss of $13.3 million or $0.42 per share, compared to an operating loss of $6.1 million or $0.27 per share in the first quarter of 2012. The incremental loss is a result of a $6.7 million decrease in government contract revenue, and $0.5 million increase in operating expenses. Revenue for the first quarter of 2013 was $4.5 million, down $11.2 million versus the first quarter of 2012. The decrease was due to the August 2012 August 2012 stop-work-order and subsequent termination of the Ebola portion of the Ebola-Marburg U.S. government contract due to a lack of available U.S. government funding. These decreases are partially offset by revenue from the intramuscular administration contract with the U.S. government for the Marburg virus that started in 2012. Adjusted research and development expenses were $13 million for the first quarter of 2013, compared to $14.5 million for the first quarter of 2012, a decrease of $1.5 million. General and administrative expenses in the first quarter of 2013, were $4.8 million compared to $2.8 million in the first quarter of 2012, an increase of $2 million. The non-GAAP net loss for the first quarter of 2013 was $13 million, or $0.41 per share, compared to the net loss for the first quarter of 2012 of $6 million or $0.27 per share. On a GAAP basis, the net loss for the first quarter of 2013 was $42.1 million or $1.32 per share, compared to a net loss for the first quarter of 2012 of $17.7 million or $0.78 per share. The difference between our GAAP and non-GAAP results was caused primarily by $26.9 million revaluation loss on our outstanding warrants. We ended the first quarter of the year with cash, cash equivalents, and invested cash of $175.2 million, which is a decrease of $12.5 million from the balance of $187.7 million at the end of last year. This cash was used to fund our ongoing operations. Beginning in the second quarter, our projected cash flow into the remainder of the year, is expected to ramp up, as we anticipate a number of near term costs related to scaling up of our manufacturing capacity and preparing for a Phase III clinical trial for eteplirsen. With that, I'd like to turn the call back over to Chris. Chris?

Yeah, operator, we can open up the call for questions.

Thank you. We will now begin the question-and-answer session. [Operator Instructions]. Our first question comes from Christopher Marai from Wedbush Securities. Please go ahead. Christopher Marai - Wedbush Securities: Hi good morning guys. Thanks for taking my question. Congratulations on the quarter. I appreciate that you have licensed additional rights to exon-skipping candidates from the University of Western Australia. I was just wondering what your estimate is of your freedom to operate with respect to the (inaudible) exons in a worldwide environment and the U.S., specifically?

Yeah. So actually, well its one of the reasons why we believe it was an important agreement to finalize, and the original license that we had with the University of Western Australia patent estate, was with kind of the initial filing, which was good, but the rights we had were to eight identified exon targets, not the full complement of all of the rare exons that we would want to have protection to commercialize. And since the license of that original patent, there was another patent that provided even more optimized sequences, provided a broader footprint geographically, and we think most of the sequences that we would want to bring in, to development for subsequent exons, would come from the second, we call the DMD-II patent estate from the UWA, and so we have now license to the -- both of those patents. The second one includes a broader geographic footprint, and even more optimized sequences, and subsequent sequences that might even be further optimized, that can be linked back to those two patent estates would be covered as well. So we believe this really is what we needed to be confident in our freedom to operate around the globe, in countries that we specified. I had listed them out at the investment conference a week or so ago, of what that covered, and we gave you that information specifically. So again, we think this is what's needed where the sequence patents is essentially, how the real estate is divided up among the DMD space. As we have reported previously, we had an opposition challenge in Europe on eteplirsen and did not prevail on exon-51, exon-46 with European patent opposition. Just as an update, they have now posted the summary of that patent opposition hearing, which does start to clock for the potential for a request for appeal. So we are evaluating our options on that internally, currently, and we have four months to actually file, if we decide to appeal this. We have two months from the posting of that, to file a written appeal, request, and the summary briefing of the appeal would be within four months of that. But again, we think this was an important agreement to give us the confidence and the freedom to operate globally for our DMD program broadly. Christopher Marai - Wedbush Securities: Great. Thanks. Then, any insight into the timeline, with respect to pre-IND meetings with the FDA to discuss some of the other exon-skipping candidates, that you'd mentioned --?

Yeah. It's a good question. So we are planning two pre-IND meetings to occur this year, and we are not ready to disclose the timing of those, but I think it's fair to say that, as we approach the end of the year, we should have good insight in terms of the agency's view on the preclinical packages needed for not only our second exon-skipping drugs that would be brought into the clinic, but subsequent exon-skipping drugs. We expect that will be less burdensome, based on the both emerging eteplirsen dataset, and whatever commitments we make on the second exon-skipping drug, from a preclinical package. So these pre-IND meetings become important, because it really starts to set the stage for how the agency might be viewing the burden of proof for subsequent follow-on exon targets, after the first, second, third, and we hope, that that will lead to a more streamlined development program, that would not take the more onerous route of not leveraging the safety dose information, dystrophin data that we have been producing, both preclinically and clinically from eteplirsen to date. Christopher Marai - Wedbush Securities: Great. Thanks, and finally one just quick one, and I will jump back in the queue here. Are we anticipating any additional data from the extension study at World Muscle this year, or any other conferences that you could highlight for us? Thanks.

Yeah. We are likely to have a clinical and safety update on our extension study, at World Muscle, and we will be determining if there are appropriate communication points prior to world muscle. But we have submitted an abstract related to this extension study, and so whatever data we can compile and analyze and incorporate in that, at that time, we will do so.

Thank you. Our next question comes from Ted Tenthoff with Piper Jaffray. Please go ahead. Edward Tenthoff - Piper Jaffray: Great. Thanks. Can you hear me okay?

Yes Ted, I can hear you. Edward Tenthoff - Piper Jaffray: Great thanks. My question is on manufacturing. I know you guys have been focused on that and appreciate the update. Can you give us a sense of kind of where scale is now, what are the hurdles, maybe a little bit more detail, just in terms of where things are going, and what needs to still be done that really gets you to the level where you can either meet requirements for the confirmatory study, and/or commercial launch?

Yes. So Ted, what I've tried to do is provide updates that we are still on track for our plans to start dosing the confirmatory study in the first quarter of 2014. You won't hear me give blow-by-blow, week-to-week activities on our manufacturing. If anything were to trip up to that timing, then we would communicate that expeditiously to let people know. So all things and activities are on-track. To provide a little more color, we are doing -- the process of the scale up currently, and that contains a lot of elements. For example, reduction to practice runs, where we can learn, right, if there is any tweaks that are required before we go for those specific test runs at the -- let's call it midscale production batch. And so, we learn from that, to make sure we mitigate any risk, when we actually do the production runs that we would want to us for the clinical trial material. This is akin to training for an Olympic event. You know what you need to do, you know what the event is and what it looks like, and so you prepare, you try to practice, you try to improve, learn from any mistakes you find along the way. But at the end of the day, when you do those production runs, you don't know what you get until you do it, and so, we will not have that final insight on whether its yield, whether its stability, purity profile, until we do those runs, which would be sort of the latter part of this year, obviously, to start getting the stability data that we would submit to the FDA, to have drug released in the first quarter of 2014. But that's the extent of the kind of insight that we are ready to give, but again, rest assured, we believe we are on our timeline, and that if we learned anything that would move us off of that timeline, we would communicate that accordingly. Edward Tenthoff - Piper Jaffray: That's helpful color. I appreciate it Chris.

Thanks Ted.

Thank you. Our next question comes from Bill Tanner from Lazard Capital Markets. Please go ahead. William Tanner - Lazard Capital Markets: Thanks for taking the question. I have a few. Chris, just as it relates to the information that the company did provide to the FDA, can you give us a sense or the scope of what was provided, as compared with that submitted initially, and I guess, wondering the extent to which the topics were winnowed down to maybe a more smaller, more manageable number of them, and just trying to determine, is it possible that there will be another iteration, or do you think that you will actually get the decision after the FDA reviews these data?

Yeah Bill, so let me clarify. So we have not submitted those two documents, as we sit here today. But I can provide some color on what we provided previously, and what we are providing coming up. We are in the stages of finalizing those documents, and we decided that the importance of these documents was more important than getting it in a week or two earlier, and so we have really gone even deeper than we had previously of combing through the literature, talking to other experts on their thoughts and advice of making the most compelling arguments for dystrophin as a surrogate and how our clinical data would support that. You see some of the evidenced in the communication around the natural history studies, and what we would expect from this age cohort, and the six minute walks that we started out, prior to dystrophin production. So we believe the two issues have been sufficiently narrowed. In that I describe it as two sides of a coin. One is to show that the dystrophin that we are producing is functional and is of a quantity and quality that is meaningful, based on the Becker patient, and studies that have been done with the natural phenotype of Becker of which the dystrophin we are producing, the truncated dystrophin is akin to the Becker dystrophin that exists in those patients, as well as the preclinical studies, those that have been done in animal models of DMD, there is dystrophic mice, dystrophic dogs, both of which have used eteplirsen or other treatment modalities to show that dystrophin that's produced, of this kind, produces functional benefit in the animal. Then of course, our own clinical data, that suggests the clinical benefit that is produced from the dystrophin we are creating. And then the other side of the coin is to make a stronger argument on our clinical outcomes, and six minute walk and other measures where we see a stability, then we would not expect to see from the natural course of this disease. So, when you even look at things like pulmonary function or cardiac function or muscle strength, if you just look, that all of these patients now are approaching 11 years of age on average, and they are doing pretty well or better than we would expect them to do, based on natural history. So we need to make that argument as compellingly, as we make the dystrophin argument, and we think each argument bolsters the other. So if we make a stronger case on the dystrophin, then you can look at the clinical outcomes through a lens that would be more supportive. Likewise, if we strengthen our clinical outcomes argument, then you start to look at the dystrophin data through a lens that says, these are probably linked and would reasonably predict this clinical outcome. So that is what we have narrowed our focus on, and -- or are concentrated on, and we think these two reviews are coming together very nicely, and we think this will provide the agency, with the sufficient information they need to make a decision. Obviously, there is no guarantee, if the FDA's prerogative to always request more information or delay a decision etcetera, but we don't believe that would be the case, because the FDA has been very responsive, we think they understand the urgency of this program, of making sure that they are clear, so we can be clear, when we are communicating to the DMD community of our intention, to try to get this drug to the market as soon as we can, and that's all I can provide at this point. William Tanner - Lazard Capital Markets: That's helpful. Then just as it relates -- obviously there is really no data to support restoration of dystrophin and having prior to yours, perhaps, and having a clinical benefit. So what is your perception of the FDAs viewpoint on the need for there to be some correlation obviously would seem like, there should be some, I guess the question is, how tight do you think they are looking at that needing to be or how convincing, taking into account that you got small numbers of patients, and you've got different ages and heights and things of that nature?

Yes, Bill, we know that there have been other dystrophin producing drugs that are still currently in active late stage development. Of which, we have not seen the type of robust consistent dystrophin levels that we've produced in a controlled manner, and so we think that we have the most compelling argument, that we are producing meaningful level of dystrophin, and that the clinical outcomes we are seeing, right, are indicative that the dystrophin levels we are producing are meaningful, right. Now I think we have other drugs that are moving forward, without that level of evidence, and so, I think we are blazing the trail, for establishing dystrophin as an important marker in this disease, I think no one disputes the fact that restoring dystrophin is going to be essential to changing the natural course of Duchenne muscular dystrophy, it’s the main essential protein that's lacking. So we think we have sufficient evidence to do this, we think the FDA will see this after they review these more extensive documents, and we are hopeful that they see it, the way we see it. But we will have to see, based on their questions and their review of this and their comments, to come to that decision.

Thank you. Our next question comes from Robyn Karnauskas with Deutsche Bank. Please go ahead.

Hey great. Thanks. [Alicia] here for Robyn. Congrats on the progress during the quarter, first of all. And our question is, just can you help us understand that Prosensa gets approved prior to your drug, what impact could it have on an orphan drug exclusivity for your drug?

[Alicia], we don't think that it would have an impact. These are different molecules, these are different composition of matter. We have a different backbone chemistry. So when you look at the guidelines for similarity on orphan drug exclusivity, as it relates to two compounds. Other than mechanism of action, we really don't see similarity on many of the other criteria. So you have, obviously a different composition of matter, a different chemistry backbone. They look at things like, how the datasets suggest that these products are different or the same. Well, I think the fact that we were seeing very similar toxicities with -- there is a person, at 0.5 mg per kg from their reported dose escalation study, and we are now at 100 times that does, at 50 mgs per kg in our current clinical study, without any of the same lab signals, and toxicities. I think it's hard to argue that these are not different, right. Then efficacy datasets is another thing, and then there is even the idea that would it benefit patients to make the drug available in a serious disease like Duchenne. So that's not something that is at the top of our list as a potential concern.

Great. Thanks.

Thank you.

Thank you. Our next question comes from Ritu Baral from Canaccord. Please go ahead. Ritu Baral - Canaccord Genuity: Thanks for taking the question guys. Mine is on the Phase III/IV confirmatory study. Just given the recent conferences, where you have had a lot of access to the KOLs and the patient community, could you bracket for us, the low end or the high end of potential size and duration of this trial, if you could just give us an idea what the range might be, and also, Ed, specifically, you and I have talked about all the different potentials for the comparator arm or comparator dataset of the trial, if you could give us your current thoughts. And the third part of that question is -- and this is for Sandy, potentially, what do you think the biggest levers are in that trial design for cost and duration of the trial, duration to data?

Yeah so Ritu, let me try to address on most of those questions and Ed is not on the call today. But basically, on the size, we've said repeatedly that we think a 60 to 80 patient treated study is sufficient. If you look at, let's say the PTC study that was 180 patients, they had two dose arms, so they had 60 patients treated versus a placebo 60-patient arm, with two dose cohorts. All right. Now, Prosensa has done a two to one randomization, so 120 to 60 patients. So we think with the data we have to-date, to guide are powering on both dystrophin and six minute walk results, and the consistency that we are seeing and the lack of variability. That is the sufficient treated population. Now the question you raise is, the control arm is the question that we want to resolve, with our discussion with the FDA. Obviously, it can range from a placebo arm to a non-exon-51 amenable population that would have the same inclusion criteria, but would avoid the challenges of and ethical considerations of doing a placebo study, with a kind of a known active agent like eteplirsen; then there is always the natural history comparison, because we have an emerging dataset on the natural history of this, which is getting easier to compare, as I just did in the call today on greater than seven years of age, and start cutting these date more specifically, to compare it to a treated cohort. The size of the overall study, if we had a control arm, then that depending on, if it's a one to one, right, that would be a 60 plus 60 or 80 plus 80. If its two to one, it would be a 60 plus 30 or 80 plus 40 population. So those details will be worked out in time, I will let Sandy comment, but I just wanted to highlight that the biggest cost driver of the confirmatory study, is the drug cost, and that is what we are incurring this year, essentially, and why our burn is what it is this year, is because we are producing much of the drug needed for the confirmatory trial, that we would begin dosing in 2014. Sandy, do you want to add anything on, how it's really not a major cost driver beyond the drug costs?

Chris, you are right about that. Its primarily the drug costs that we are focusing on and we have been in talks with various CMOs in the U.S. and the EU as well as in Asia, both in our subunits as well as in API, and we are looking at various arrangements, such as joint ventures or maybe even buying suites in these various manufacturers, putting our employees in the facilities that the CMOs own, so that we can get more control and ownership over the process, and we are certainly putting our financial resources in there to ramp up the manufacturing, which obviously would then drive down the price. As we have guided previously, this year, we're spending between $85 million to $115 million, a majority of that, [by this] accelerated or non-accelerated scenario, is in drug costs and manufacturing operations. So the whole goal is to make sure that not only do we have manufacturing, but also backup facilities, and production efficiency, which really goes to your question. So you cannot really guide specifically on what production efficiencies we can get to drive down the costs, but in every month or six weeks that goes by, we feel better and better in terms of the progress we have made, in terms of both manufacturing, as well as the manufacturing efficiencies, which is where we hope that we can contribute, in terms of containing the costs related to the Phase III trial. Ritu Baral - Canaccord Genuity: Got it. So you are focused on getting six months to a year of supply for those 80 patients on treatment, that you are anticipating for the trial?

Well Ritu, it's a campaign, right. So you have constant drug production runs, but the setup costs, and the initial runs, which would be usable in the clinical trial, right, are a big part of that. But obviously, it's not to say we wouldn't be incurring, you know, manufacturing costs moving forward. I mean, this is a campaign that will continue to increase, as the scale increases, the cost of manufacturing will increase. But we get to a point where every vial that's produced, from mid-scale or large scale, is either going to drive value with an essential part of our clinical program, or is going to drive value in terms of a commercial sale, in the marketplace. So we see every investment in manufacturing as one of the best returns on investment that we can make at this point.

Thank you. Our next question comes from Heather Behanna from JMP Securities. Please go ahead. Heather Behanna - JMP Securities: Hey guys, thanks for taking the question. Just a follow-up slightly on the manufacturing vein. Can you give us any color on discussions you've had with FDA or internal agencies on which dose you will use moving forward?

Yeah, we have made our case for 30 mgs per kg based on the fact that the biochemical data supports that 30 mgs per kg is producing as much, and actually numerically more 48 weeks than the 50 milligram per kilogram dose. Again, the stability we see, even in the 30 mg patients now is very good and sufficient, and so again, that is our stance. Again, the confirmatory study design has not been finalized at this time, and so we expect further discussions with the FDA. But as I stated earlier, Heather, I mean, you can only accomplish so much in these FDA meetings. We have a very ambitious set of questions and topics that we'd like to cover. The FDA knows this, they are encouraging that there will be opportunities to discuss all of these issues, over the coming months and quarters, and so we expect to do that. So as we get more specific perspective on the dose, we will provide that to the market.

Thank you. Our next question comes from Brian Skorney from Baird. Please go ahead. Brian Skorney - Robert W. Baird: Yes good morning guys. Thanks for taking the question. I guess, just in regards to some of the question, the FDA has had in your initial meeting, I am just wondering, how focused are they on the ability to adequately quantify dystrophin on western blot and the actual relative differences in (inaudible) intensity produced in healthy patients. Becker patients with an (inaudible) lesion, ending with exon-51 and eteplirsen treated patients?

So Brian, we have collected dystrophin in a very specific way. As a reminder, we had to submit this protocol, going back to the summer of 2011 for a review with this division, where we outline this as our primary endpoint, and how we were going to be collecting the dystrophin etcetera. So we are summarizing for them again, why we selected the methodology we did. But we believe that it was selected with an informed view. This was after talking to a lot of experts in the field, this was after looking at the precedents that was established by those before us, PTC, Prosensa, GSK, who were using immunohistochemistry to help them identify the dystrophin that they were producing, and we do believe that the information gleaned from a specific muscle tissue that you can look at, specifically for dystrophin and looking at percent positive fibers, as well as intensity, as well as the localization and the uniformity of that across the samples. This is a lot of great information to have, when you are trying to interpret a muscle biopsy sample, across the musculature of the human subject. We have supportive data that we are showing the appropriate length of the protein by RT-PCR and we have a supportive evidence on Western blot, that the protein has been produced. We think all of this in totality, provides the evidence that is needed, to show that this dystrophin is meaningful and we believe the literature, the preclinical models show that its functional, and we believe that the clinical outcome show that its reasonably likely to predict clinical benefits. So I can't state for sure, what each mind of the agency, within the division are thinking specifically. But we believe we have outlined very clearly, our methodology, how we quantify that. We know that the research community and those that are on the forefront, of looking at new markers, new assays, new ways of testing dystrophin. We admire and respect all of these efforts, and we expect that the field will evolve and grow. Unfortunately, we have to base -- the basis of our potential approval, on what we have collected, and we collected what at the time, was state of the art, and the most meaningful. So unfortunately, the FDA will have to evaluate the data that we have in front of us, and they have actually been (inaudible) to quickly adopt newfangled approaches. It's not saying in the future they won't, say a new assay or a new way of quantifying is a better way, than what the standard of practice has been. But that's not the state we are in, as we sit here today. So I know there is a lot of chatter out there about different ways and the forward-looking approaches to this, and we will be right at the forefront. We expect to be industry -- maintain our industry focus and expertise on dystrophin and look at these methodologies. That's the big question, can we make the compelling case on the methodology that we use for the study.

Thank you. Our next question comes from Tim Lugo from William Blair. Please go ahead. Tim Lugo - William Blair: Thanks for taking the question. Can you give us an update on your plans for the non-ambulatory patients? Will you be sharing data from the Phase IIb and your white papers to the FDA. Will you include these patients in some sort of Phase IV or in maybe some sort of offshoot of the confirmatory studies?

Tim, it's a good question. We actually believe that we have good evidence in our existing study, with the two patients who rapidly lost ambulation, shortly after enrolling in our study. Just to put that in perspective, both of these twins were below 250 meters after four weeks on -- after enrolment in the study. Long before we would expect dystrophin to be produced, and the Mazzone study I referred to earlier had those patients who were below 250, had the highest risk of losing ambulation over a year to two year timeframe, from his natural history study. So we have now continued to treat those patients. They were two of the boys who showed increase in dystrophin from week 24 to week 48. We have shared some of the pulmonary function data, that we believe is, I guess, a stabilization on a measure that starts to more rapidly progress, once you lose ambulation, and we have other upper arm extremity tests and (inaudible) test and other things that are non-ambulatory measures. So we believe where we sit today, we have one of the most robust, non-ambulatory data sets that exists in DMD today, on these two patients. And we expect that there will be other experienced studies, whether that will be a companion study to our pivotal, that's not determined at this point. It could be that if any patient's, whether on placebo or some other control group, were to lose ambulation, we would likely continue them and continue to follow them on treatment, and look for those outcomes. So we think there is a lot of different ways, beyond what we have already collected to date, to support the non-ambulatory population. But going back to the proof of concept, there is no reason to suggest that we wouldn't be producing dystrophin in the same way, based on the results we have had to date, in any DMD boy, who is amenable to an exon-51 skip, and that dystrophin that we are producing, wouldn't lead to some level of functional benefit, and it's harder to determine the right measures of functional benefit in these other populations, outside of six minute walk tests in the type of population that we identify for our study.

Thank you. Our next question comes from Joe Schwartz from Leerink Swann. Please go ahead. Joseph Schwartz - Leerink Swann: Great. Thanks and congrats with all the progress. Wanted to ask, how you expect your deliverables to be able to show a concurrence between the doses of that person administered with the functional changes being achieved in the dystrophin production? In some respects, there seems to be a lack of correlation, but we obviously have less data than you, so you expect that this will be a strong argument in your deliverables?

You know, it's not something that we have ever suggested, that we would be able to show some type of tight, linear, correlation. Now you are adding another criteria, which is does, right. So I think it's hard enough to suggest that, for example, 30% dystrophin positive fibers will translate to a benefit over an untreated patient of 50 meters. But if we show 45% dystrophin positive, if that goes up to 65 meter benefit, you are dealing with a sampling bias of a tissue sample that's representing the full musculature, and you are using an effort-dependent test, that is highly variable based on other phenotypic characteristics and age and demographics, and trying to correlate those two things, in a very linear type fashion. So that's not an expectation that we have even set, but we do believe that there is a threshold, and that we are above that threshold, for which we would expect clinical benefit to manifest itself, based on the levels of dystrophin we are producing. And that we believe, is the level of evidence we need to provide. It's unfortunate in diseases like this, where there is no clear biomarker, and there is no easy way to detect dystrophin levels other than muscle biopsies at this point, and we know there is new approaches, that might make it less invasive and easier to do that, and we look forward to those new methodologies. But when you are dealing with a disease like this, you can either throw up your hands and say, well, we can never approve drugs that might be really active against these diseases, because we just don't know enough information, and it's not as tightly correlated. So there is no pathway to approve these drugs. All we can say, let's work with the information we have, and is there sufficient evidence, and again, we like the Accelerated Approval pathway that the FDA has at their disposal, which is reasonably likely to predict, and that would be confirmed in a larger clinical outcome based study. And so, Tim this study -- this is where we have to -- or Joe, we have to lead ourselves, because we don't have that level of information for this particular disease.

Thank you. Our next question comes from Reni Benjamin from Burrill and Company. Please go ahead. Reni Benjamin - Burrill Institutional Research: Hi good morning Chris. Thanks for taking the question. Just goes to the natural history slide. You mentioned that 330 meters of baseline maybe a good cutoff when enrolling in a study. Is there an upper limit that you have found, that may also be a good cut off, and can you remind us of the range of the baseline, six minute walk on the eteplirsen treated patients?

Yeah. So basically, we enrolled patients that could have qualified for the study, having a baseline of 200 to 400 meters at baseline. This is their first day one, what we call our screening visit, and we allow, on that first screening visit, a variable of plus 10%, meaning they could have been below 440 meters and still qualify for the study. Now, when we use maximum score, the reason the average value, that baseline or higher, when we use maximum mean scores, is because the second day, they could have been above that, or above 400 on average, and we had a few patients who qualified above 400. I think one, I don't recall specifically who might have been above that 440 mark on day two. But again, all of them were within that, let's call it, 250 to 450 range, that's the broader range, including the day two scores. I think on the upper end, I think we would look a little suspect at kids who are above, let's say 450 meters, at least on a consistent basis, over a couple scores. If that is not a healthier than normal DMD boy. We would also -- as we know, from the natural history studies, including boys that are less than seven years of age, and I think both PTC and Prosensa have made comments to this effect as well, that they are still improving, they are still growing. So doing studies in a population that includes patients below 7, can be very confounding, because you don't -- I think it's a lot more variable to interpret a potential treatment effect, when you have got a large swathe of patients, that might naturally be improving, whether they are on drug or not. So, we believe the population we selected, is exactly who we intended to, which is those that would not be healthy, would not be young, would not be expected to be improving and would be on a decline. So again, we think both our early treated group, which averaged in the 380s on six minute walk, and then the placebo group, with average below 330, at the time, we were producing dystrophin, both of those are levels of evidence, of stability that you would not expect to see in those populations.

Thank you. Our next question comes from Kim Lee from Janney Capital. Please go ahead. Kimberly Lee - Janney Capital Markets: Good morning. Thanks for taking the question. First one is, in your previous discussions with the FDA, kind of what are the things, concerns, if any were brought up, besides their requirement for showing that dystrophin does show clinical outcome. Is there any other color you can provide there? And what were the FDA thoughts on exclusion of certain data, like data from the twins? Thanks.

Yes. I mean, look, we have highlighted the most salient, relevant points that we feel, related to the FDA discussions. Again, we were encouraged that, we are not making an issue of the sample size, and it was more on, let's understand the quality and quantity of data that was collected from that sample size. So we were very encouraged by that. And again, they gave flexibility statement on the safety, is that if they did accept this for an Accelerated Approval filing, that we could then supplement that NDA filing with some initial experience from any confirmatory study, if we needed that to form the basis of an approval. So again, we have shared what we think are the most relevant outcomes of the FDA meeting, and again, we described and explained the twins, we think very sufficiently, and of course, they want to see all the data, right. They want to make their own interpretation and its though, they do this, when they do a review, and we expect that they are going to do a similar type of assessment, not to the same extent as they would after an NDA filing. But I expect they are going to review our data with a measured eye, and so we explained the twins as best we can, and we don't think that that would impede their decision on whether this is a feasible dataset for accelerated approval filing. Again, we think there is advantages, if there is a silver lining, we are collecting some excellent information in a non-ambulatory population, as a result of these two boys. So again, we are looking at this very favorably, and I believe, the FDA will look at this appropriately and pragmatically.

Thank you. Our last question comes from Debjit Chattopadhyay from Emerging Growth Equities. Please go ahead. Debjit Chattopadhyay - Emerging Growth Equities: Good morning guys, and thank you for the questions. Just have two questions. First, I mean, what differences are you seeing with the other exon drugs versus eteplirsen, in terms of therapeutic dose and efficiency of exon-skipping? Number two is, if you compare the current Phase IIb patients, instead of looking at the natural history of DMD, and compare them with the most severe Beckers muscular dystrophy phenotypes, how do they stack up versus the second group, the severe phenotype of Beckers muscular dystrophy? Thank you.

Yeah absolutely. So Debjit, I am sorry, can you repeat the first question again? Debjit Chattopadhyay - Emerging Growth Equities: Well I was just wondering if, in terms of the other exon-skipping drugs, what are you seeing in terms of --?

Yeah, okay. So on the other exon-skipping drugs, again, we are in preclinical development, and there are not -- there is no plans for specific exon targets. There was preclinical work. Any functional (inaudible) would be done in the dystrophic mouse model, the MDX, which is a surrogate, it's at exon-23 skip. So what we have is, we have optimized the sequences, for exon-45, 53, and 50 and have identified those lead candidates, and so what we can extrapolate at this point, this early stage, is that the exon-skipping efficiency is in the range, we would like to see it, and that would be predicted, based on what we know about eteplirsen and the sequent we have for exon-51, that these would have a similar ability to produce the dystrophin levels we are seeing with eteplirsen, at a standard dose, at a similar dose of, let's say 30 mgs per kg per week. So we won't know for sure, until we actually dose patients, collect some dystrophin from those new exon targets, to know if that's the case. Regarding your second question, Becker muscular dystrophy has a very milder course, and oftentimes, there is a wider range to Becker. So some would be described as a mile Duchenne patient, and that ranges from an almost normal healthy individual, which can live most of their life, without even knowing they have a muscular dystrophy, never requiring a wheelchair and living a kind of a full life expectancy. So, what we see right now, in these 10 boys that were still ambulant, is the stability that if we can continue that on an ongoing basis, that would be very encouraging, that if we started this drug in an earlier healthier population, we could really have an opportunity to change the natural course of Duchenne, and make it more akin to what we would see in Becker muscular dystrophy, which is a much milder phenotype, which allows ambulation to continue largely into adult life.

Thank you. I will now turn the call back to Chris Garabedian for closing remarks.

Okay. Thank you, operator, and thank you everybody for your interest and calling into this quarterly update. We are prioritizing this program in our interactions with the FDA, as well as the activities on clinical regulatory, and manufacturing. We understand the urgency of doing everything we can, to get this product to the patients who need it as quickly as possible, and we believe the FDA is a partner in trying to help us figure out, how to do that in the best way possible. So thank you, we look forward to giving you periodic updates along the way, and thank you for your interest in Sarepta.

Thank you. Ladies and gentlemen, this concludes today's conference. Thank you for participating. You may now disconnect.