Company: SION
Filing Date: 2025-03-20
Form Type: 10-K
Source: 0002036042-25-000005
Chunk: 17

Company: Sionna Therapeutics, Inc.
Filing Date: 2025-03-20
Form: 10-K
Item: Item 1
Chunk 17
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 Since disclosing interim data, we have completed dosing in the MAD part of the SION-451 trial, and the final MAD cohort of the SION-719 trial, to evaluate 120 mg SION-719, is planned. The additional completed cohorts evaluated 225 mg and 25 mg (fed) of SION-451 and 160 mg of SION-719, each dosed BID over 10 days. All MAD data, including from the recently completed cohorts, remain blinded to individual subject treatment assignment. Both compounds were generally well tolerated in these additional MAD cohorts. There were no serious adverse events (“SAEs”), and most treatment-emergent adverse events (“TEAEs”) were mild to moderate. There were no TEAEs related to liver function tests and no TEAEs that led to discontinuation of trial drug.  The Part C of each trial, in which we are evaluating the effect of food on the PK of each product candidate and the bioequivalence of a tablet formulation, is ongoing. We expect topline data for both trials in the first half of 2025. 

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Interim Phase 1 Trial Data for SION-719 

As of January 14, 2025, the interim data cutoff date, over 60 healthy subjects had been dosed in the Phase 1 clinical trial of SION-719. The trial was designed to enroll eight subjects, randomized 3:1 active:placebo, in each dosing cohort. As of the data cutoff date, five SAD cohorts had been completed, evaluating single doses of 20 mg, 40 mg, 80 mg, 160 mg and 20 mg taken with food to provide a preliminary assessment of the effect of food on PK, and three MAD cohorts had been completed, evaluating 20 mg, 40 mg, and 80 mg of SION-719 BID over 10 dosing days. As of the data cutoff date, all data remained blinded to individual subject treatment assignment, with the exception of selected individual subjects unblinded for administrative and study planning purposes according to the clinical trial protocol. 

SION-719 was generally well tolerated at all dose levels administered based on interim Phase 1 clinical data as of the data cutoff date of January 14, 2025. There were no SAEs. Most TEAEs were mild to moderate (Grade 1 or Grade 2), and no TEAEs led to the discontinuation of trial drug. The most common TE