Sionna Therapeutics (SION) Corporate presentation summary

Leadership and expertise

• Executive team and board have extensive experience in biotech and CF drug development, with backgrounds at leading companies and institutions.

• Founders have over 15 years of CFTR research, originating from Genzyme and Sanofi, and supported by CFF.

Scientific and clinical progress

• Focused on stabilizing NBD1, a critical domain in CFTR, to address the F508del mutation present in ~90% of CF patients.

• NBD1 stabilizers SION-719 and SION-451 demonstrated increased CFTR half-life to wild-type levels in preclinical studies.

• Phase 1 trials for SION-719 and SION-451 showed favorable safety, tolerability, and pharmacokinetics.

• SION-719 is being evaluated as an add-on to standard of care (SOC) in a Phase 2a trial; SION-451 is the anchor for dual combinations in ongoing Phase 1 trials.

Pipeline and milestones

• Robust pipeline includes NBD1 stabilizers and complementary modulators (TMD1- and ICL4-directed correctors).

• Key near-term milestones: Phase 2a POC data for SION-719 and Phase 1 dual combo data for SION-451 expected mid-2026.

• Dual combination strategy aims to select the optimal NBD1-based combo for Phase 2b trials.