Sionna Therapeutics (SION) Cantor Global Healthcare Conference 2025 summary

Company progress and pipeline updates

• Completed Phase 1 studies for two NBD1 stabilizers, both exceeding PK and exposure targets and showing good tolerability.

• Advancing SION-719 as an add-on to standard of care in a proof of concept study and SION-451 as part of a proprietary dual combination, with both studies expected to read out in mid-2026.

• Initiated a healthy volunteer dual combination study for SION-451, with Phase 2a proof of concept for SION-719 to start later this year.

• Ended Q2 with $337 million in cash, providing runway into 2028 and beyond key milestones.

Market landscape and unmet need

• Cystic fibrosis market is valued at $11 billion, projected to grow to $15 billion in 3–4 years, currently dominated by a single player.

• Only a third of patients on standard of care achieve normal CFTR function, leaving significant unmet need.

• Improving sweat chloride and FEV1 are key goals for enhancing quality of life and life expectancy.

Scientific and clinical rationale

• NBD1 is a critical domain in CFTR protein, with the F508del mutation affecting 85–90% of patients.

• NBD1 was previously considered undruggable due to shallow binding pockets; success achieved through structure-based biology and fragment-based chemistry over 15 years.

• Correcting NBD1 alone can match the efficacy of current triple therapy, with combinations potentially restoring wild type CFTR function.