Company: SION
Filing Date: 2025-01-17
Form Type: S-1
Source: 0001193125-25-008474
Chunk: 35

Company: Sionna Therapeutics, Inc.
Filing Date: 2025-01-17
Form: S-1
Chunk 35
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 candidate. Preclinical studies, Phase 1 and Phase 2a clinical trials are primarily designed to test safety, to study pharmacokinetics and pharmacodynamics, and to understand the side effects of 26

product candidates at various doses and dosing schedules. Success in preclinical or animal studies and early clinical trials does not ensure that later large-scale efficacy trials will be
successful, nor does it predict final results. Our product candidates may fail to show the desired safety, tolerability, pharmacokinetic profile, and efficacy in clinical development despite positive results in preclinical studies or having
successfully advanced through initial clinical trials, particularly because our NBD1 stabilizer product candidates target the NBD1 domain of the cystic fibrosis transmembrane conductance regulator (“CFTR”) protein, a novel target which has
not yet been tested in CF patients.

Many companies in the pharmaceutical and biotechnology industries have suffered significant setbacks in
late-stage clinical trials even after achieving promising results in preclinical testing and earlier-stage clinical trials. Such setbacks have occurred and may occur for many reasons, including: clinical sites and investigators may deviate from
clinical trial protocols, whether due to lack of training or otherwise, and we may fail to detect any such deviations in a timely manner; patients may fail to adhere to any required clinical trial procedures, including post-treatment follow-up; our product candidates may fail to demonstrate effectiveness or safety in certain patient subpopulations or at all; or our clinical trials may not adequately represent the patient populations we intend to
treat, whether due to limitations in our trial designs or otherwise. Data obtained from preclinical and clinical activities are subject to varying interpretations, which may delay, limit or prevent regulatory approval. In addition, we may experience
regulatory delays or rejections as a result of many factors, including changes in regulatory policy during the period of our product candidate development.

Similarly, from time to time, we may publish interim, topline or preliminary results from our preclinical studies and clinical trials, which are based
on a preliminary analysis of then-available data. We also make assumptions, estimations, calculations and conclusions as part of our preliminary analyses of data, and we may not have received or had the opportunity to fully and carefully evaluate
all data. As a result, the results and related findings and conclusions are subject to change following a more comprehensive review of the data related to the particular study or trial. Interim results from clinical trials that we may complete are
subject to the risk that one or more of