Louise Rodino-Klapac
Analyst · Bank of America. Your line is open
Thanks Doug. The significant achievements we've made recently with respect to SRP-9001, our gene therapy candidate to treat Duchenne muscular dystrophy, represents not just an important moment for Sarepta, but more importantly, for the patient community. Notably, we announced this past Friday, July 29, our intent to cement a BLA seeking accelerated approval for SRP-9001. We're a thrill with this development as it speaks to the strength of the underlying science and the data we've generated to date. I want to thank the team for all their work supporting this positive outcome and engaging with the FDA. While also working on the BLA submission in parallel. Due to this major effort, we are well-positioned to submit our BLA this fall. The data we announced in early July including important functional clinical results from studies 101, 102, and 103, and our integrated analysis will support this BLA submission. To remind you, Study 101, and 102 is clinical material, and Study 103 is commercially representative material. I'll now briefly recap these results for you. Starting with Study 103, or ENDEAVOR. We showed the patients in Cohort 1 with an end of 2020 improved four points from baseline on NSAA. Pretreatment had a mean baseline NSAA 22, and at week 52 improved mean of 26, approaching the top end of the NSAA scale. For example, these patients can now perform two activities unassisted that they were not able to perform prior to therapy. The before activities that they needed assistance risk that they now can do on their own. Equally impressive SRP-9001 treated patients improved 3.8 points on unadjusted means and 3.2 requiring of 52 weeks on NSAA compared to the propensity Master external control group, with a p-value of less than 0.0001. These results are impressive as they demonstrate that commercially representatives SRP-9001 improves motor function, and further confirms our confidence in the treatment effect of our therapy, increasing the probability of success for EMBARK or Study 301. Also, these data increase our level of conviction for EMBARK, because the same commercially representative of SRP-9001 material is being used in both ENDEAVOR and EMBARK. Speaking of EMBARK, our clinical operations team has also executed flawlessly. And as a result, enrollment in the study is nearly complete. In summary, Study 103 demonstrated improvements across all key secondary functional endpoints such as time derived, 10-meter walk run, time to extend four steps, and 100-meter walk run. Based on these data, patients receiving SRP-9001 improved significantly on every functional measure. I'll now recap our long-term results. These data are particularly important, because they answered two of the most common questions. Are these data clinically meaningful? And is the effect durable? First, we will look at our original four patients after four years of treatment on SRP-9001 from Study 101. As a reminder, we conducted two analyses. NSAA change from baseline over four years in the four treated boys and then in comparison to an external control group using propensity score waiting. These data showed that patients with Study 101 demonstrated a mean increase of 7-points in total NSAA score from baseline in year four. Importantly, as these are older patients, around nine years old at year four, and because Duchenne is a disease that gets progressively worse, these patients would, according to the natural history of Duchenne being the steep decline phase of their disease. However, instead of declining, they've increased their function and maintain that increase, thereby demonstrating a distinct treatment effect that increases over time, supporting durability of SRP-9001. Based on the individual patient level data we showed, it's clear that all of these patients have remained stable and well above their baseline for this time period. No single patient drove the mean of the group. Further, when we compare the treated patients through propensity matched external control, we observed nearly a 10-point difference on unadjusted means and a 9.4 point difference using lease squaring with a p-value of 0.01 at four years. As an example, the SRP-9001 treated patients can now do five activities for those with external control group were not able to accomplish. We are pleased to see that the treatment effect has continued to increase over time. It's also important to note that precipitous decline in years three and four of the external control group. These boys are now in a steep part of the decline phase of our disease, whereas the treated patients remain stable. Moving now to our two-year functional results from 20 patients, who received SRP-9001 in Part 1 of Study 102. At one year, we saw a 3-point median difference between the SRP-9001 group and the external control group. At week 96, this grew to a 5-point median NSAA difference with a p-value of 0.0001. The fact that, only approximately half the patients in the treated group received a target dose that makes these results even more impressive. I will now review the integrated efficacy analysis for all patients in studies 101, 102 and 103, who received a target dose of 1.33x10 [ph] another 14 per sector GMs per kilogram compared to an external control. And this integrated analysis of one-year functional data for patients who receive the target dose of SRP-9001. 52 in all, we show that the treated patients improved 2.4 points in NSAA total score from baseline. When compared to propensity-weighted external control group, NSAA change from baseline one year after treatment for the treated patients were 3.1 points higher on unadjusted means and 2.4 points higher using lease square mean, with a p-value of less than 0.0001. As you can appreciate, these data now reinforce the consistency of NSAA improvements across three independent sites and show mean improvements across key secondary functional endpoints, such as time to rise and 10-meter walk run. We are also pleased to share expression data from all of the studies, which demonstrated consistency for both our clinical and commercial manufacturing process. Further, the safety profile of SRP-9001 remains consistent and manageable with no evidence of clinically relevant complement activation. In summary, these new data and our integrated efficacy analysis has demonstrated that SRP-9001 performs well-above what natural history will predict and support potential as a disease-modifying agent. Now turning to Limb-girdle muscular dystrophy, or LGMD programs in our gene therapy franchise. For SRP-9003 and our other LGMD programs, we continue to make progress with respect to building the necessary steps of our manufacturing process, including LGMD-specific assay development and validation. In addition, our natural history study in Germany also continues to enroll and represents a key component of our LGMD development pathway. Our commitment to advance the best science and then translate that science into therapies for rare disease patients around the world remains strong. The progress we've made to date based on the clinical evidence, as well as a dedicated and tireless tumor scientists and professionals positions us are favorably to deliver on this commitment. Thank you to the patients, families and investigators for their role in bringing forth these important therapies. I will now turn the call over to Dallan for an important update on our commercial activities. Dallan?