Company: SION
Filing Date: 2025-05-12
Form Type: 10-Q
Source: 0002036042-25-000016
Chunk: 452

Company: Sionna Therapeutics, Inc.
Filing Date: 2025-05-12
Form: 10-Q
Item: Part I, Item 2
Chunk 452
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 two randomized, double-blinded, placebo-controlled Phase 1 clinical trials of our highly potent NBD1 stabilizers—SION-719 and SION-451—evaluating the safety, tolerability and pharmacokinetic ("PK") profile of single ascending doses ("SAD") and multiple ascending doses ("MAD") of each product candidate in healthy subjects. As of the interim data cutoff date of January 14, 2025, five SAD cohorts and three MAD cohorts of SION-719 had been completed, with over 60 healthy subjects dosed, and six SAD cohorts and three MAD cohorts of SION-451 had been completed, with over 70 healthy subjects dosed. Both SION-719 and SION-451 were generally well tolerated based on interim Phase 1 clinical data as of the interim data cutoff date. As of the interim data cutoff, at both single and multiple doses, SION-719 and SION-451 exposures were achieved that have the potential, based on our preclinical cystic fibrosis human bronchial epithelial (“CFHBE”) model, to provide clinically meaningful benefit if SION-719 or SION-451 were administered as part of a dual combination or as an add-on to the standard of care. We recently completed dosing in the SAD, MAD and food effect and tablet bioequivalence parts of both Phase 1 trials. Both compounds continued to be generally well tolerated, and their safety profiles remained consistent with prior disclosures. Topline data from the Phase 1 trials are expected in the second quarter of 2025.

We intend to evaluate an NBD1 stabilizer in combination with the current standard of care in CF patients in a proof-of-concept trial, which we plan to initiate in the second half of 2025, following completion of a drug-drug interaction trial.

We are also developing a portfolio of complementary CFTR modulators 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 (“TMD1”), and has completed Phase 2 clinical trials. In addition, in December 

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2024, we completed a Phase 1 clinical trial