Sarepta Therapeutics (SRPT) investor relations material

Commercial business and competition

• Exon-skipping therapies have over a decade of use, established safety and long-term real-world evidence; ~90% of patients use home dosing, supporting adherence and retention as Dyne’s exon 51 program approaches potential competition in the coming year.

• Stable patients are expected to be a core base; new-patient competition will center on product attributes, including time on market, safety experience and evidence supporting benefit-risk. Dyne’s label will shape the competitive landscape.

• Physician visits typically occur once a quarter or less often; treatment decisions are expected to reflect patient and family experience, observed stability, safety and benefit.

• ELEVIDYS demand was described as a clean baseline, reflecting starts generated before sales-force expansion and newer data were in place; longer-term growth timing depends on emerging trends and Cohort 8 readouts.

Gene therapy and regulatory outlook

• The stated regulatory standard for DMD gene therapy is randomized controlled evidence of clinical benefit before extrapolating from microdystrophin expression; a robust safety database is also important to assess benefit-risk.

• ELEVIDYS safety exposure exceeds 1,200 ambulatory patients and 1,500 patients overall, supporting a broader safety database than smaller single-arm programs.

DM1 and FSHD programs

• The αvβ6 peptide ligand delivery approach has shown high muscle concentrations and robust knockdown preclinically and in single-ascending-dose studies for DM1 and FSHD, without dose-limiting toxicity.

• Upcoming DM1 Phase I-B data will emphasize DMPK knockdown and splicing correction; functional measures including vHOT will be presented, but small studies are not powered for comparisons across programs.

• Management views 10%-15% knockdown as potentially near the cusp and 20%-25% as an interesting range; the goal is higher splicing correction, with DM1 dosing planned up to 8 mg/kg siRNA.

• Accelerated approval is viewed as possible for DM1 based on vHOT or a validated splicing biomarker; FSHD approval could also be accelerated, with a randomized confirmatory study using longer-term clinical endpoints.

• FSHD single-ascending-dose cohorts showed ~90% inhibition of DUX4-regulated genes at doses below those in the update expected later this year; >70% inhibition in the multiple-dose study would be considered exceptional.