Solid Biosciences (SLDB) investor relations material

Pipeline and clinical program updates

• Focused on three main areas: Duchenne 003 gene therapy, Friedreich's ataxia (FA) program SGT-212, and the AAV platform (SLB101/POLARIS-101 capsid).

• Duchenne 003 program has dosed over 50 patients, with robust biomarker and safety data showing muscle integrity improvements and no drug-induced liver injury.

• SGT-212 for FA targets both cardiac and CNS manifestations using a dual administration route, with promising early safety and coverage of the dentate nucleus.

• CPVT program progressing slowly by design, with dosing planned for this year.

• Anticipated milestones include increased FA dosing, FDA meetings for registrational studies, and ongoing Duchenne trial enrollment.

Scientific and clinical insights

• Duchenne program features a novel transgene with R16, R17 binding domain and unique CK8 promoter, enhancing muscle and cardiac targeting.

• POLARIS-101 capsid binds integrin receptors, clears rapidly from blood, and shows consistent biomarker expression across methods.

• Comprehensive biomarker analysis includes micro-dystrophin, sarcoglycans, nNOS activity, and muscle integrity markers (CK, ALT, AST).

• Cardiac monitoring shows normalization of ejection fraction in all treated patients with prior deficits.

• Safety profile remains strong, with only minor, resolved adverse events and no drug-induced liver injury.

Regulatory and strategic updates

• Multiple FDA meetings confirmed the novelty of the Duchenne 003 program and ongoing unmet need in Duchenne gene therapy.

• FDA prefers randomized controlled trials over open-label studies for functional endpoints; double-blind placebo-controlled trial is underway.

• Functional data to be collected and analyzed in July-August, with a revised statistical plan submitted to FDA based on their feedback.

• Fall FDA meeting planned to discuss data and potential accelerated approval pathway.

• Data and regulatory updates to be shared with the investor community after FDA discussions.