Sionna Therapeutics releases Phase 2a SION-719, Phase 1 SION-451 dual-combination data presentation

• Sionna Therapeutics released clinical topline results for its NBD1 stabilizer programs SION-719 Phase 2a in cystic fibrosis.
• PreciSION CF missed the key activity endpoint, showing a -1 mmol/L placebo-adjusted sweat chloride change when SION-719 was added to Trikafta.
• Development of SION-719 as an add-on to standard of care will not advance.
• SION-451 dual-combination Phase 1 met predefined safety, tolerability, pharmacokinetic objectives; preferred regimen was SION-451 BID with SION-2222 QD.
• Cash and cash equivalents were about $268 million as of 2Q26; capital-preservation actions planned while next steps are evaluated.

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