Company: SION
Filing Date: 2025-08-11
Form Type: 10-Q
Source: 0002036042-25-000047
Chunk: 455

Company: Sionna Therapeutics, Inc.
Filing Date: 2025-08-11
Form: 10-Q
Item: Part I, Item 2
Chunk 455
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451, our lead NBD1 stabilizer product candidates, in over 200 healthy volunteers. The trials assessed the safety, tolerability, and pharmacokinetics ("PK") of single and multiple ascending doses of each product candidate, as well as food effect and tablet bioequivalence. 

Both SION-719 and SION-451 were generally well tolerated in these trials, with no serious adverse events, treatment emergent adverse events that led to discontinuation of drug, or dose-limiting toxicities observed. The Phase 1 data also supported the use of a tablet formulation in future trials and indicated that both compounds could be dosed in a fed or fasted state. Both NBD1 stabilizers met exposure thresholds that we believe, based on our preclinical CF human bronchial epithelial ("CFHBE") model, have the potential to provide clinically meaningful benefit if administered as an add-on to SOC or in proprietary dual combinations with complementary modulators. 

Based on the Phase 1 results, we are advancing both NBD1 stabilizers —SION-719 and SION-451— to the next phase of clinical development. 

We plan to progress SION-719 into a Phase 2a proof-of-concept trial in CF patients evaluating the compound as an add-on to SOC, pending completion of a drug-drug interaction study to confirm that SION-719 can be dosed with the SOC according to its label. We are on track to initiate the Phase 2a trial in the second half of 2025. SION-451 will advance to a Phase 1 dual combination trial in healthy volunteers evaluating SION-451 in dual combinations with each of galicaftor (SION-2222) and SION-109, two of our complementary CFTR modulators. The trial will evaluate the safety, tolerability, and PK of varying doses of the dual combinations. Initiation is anticipated in the second half of 2025.

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Table of Contents

Strategic In-Licensing & Complementary Modulators

Our portfolio of complementary CFTR modulator candidates are designed to work synergistically with our NBD1 stabilizers to improve CFTR function, as seen in preclinical models. During 2024, we in-licensed three clinical-stage compounds from AbbVie Global Enterprises Ltd. (“AbbVie”) to expand our portfolio of combination product opportunities, including galicaftor (SION-2222), a complementary modulator which targets CFTR’s transmembrane domain 1 (“