Company: SION
Filing Date: 2025-02-03
Form Type: S-1/A
Source: 0001193125-25-018825
Chunk: 21

Company: Sionna Therapeutics, Inc.
Filing Date: 2025-02-03
Form: S-1/A
Chunk 21
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 limited operating history. We have incurred operating losses in each year since our inception. Our net losses were $47.3 million and $40.2 million for the years ended December 31, 2023 and 2022,
respectively. We had an accumulated deficit of $165.2 million and $119.4 million as of September 30, 2024 and December 31, 2023, respectively. Substantially all of our operating losses have resulted from costs incurred in connection with
our research and development programs and from general and administrative costs associated with our operations. Our prior losses, combined with expected future losses, have had and will continue to have an adverse effect on our stockholders’
deficit and working capital.

Since our inception in 2019, we have devoted substantially all of our efforts and financial resources to the
development of our product candidates, the continuation of ongoing clinical trials, the commencement of new clinical trials and ongoing manufacturing to support our product candidates. Biopharmaceutical product development is a highly speculative
undertaking and involves a substantial degree of risk. We have not yet demonstrated an ability to conduct later-stage clinical trials, obtain regulatory approval, manufacture any product on a commercial scale or conduct sales and marketing
activities necessary for successful product commercialization, and there is no assurance that we will accomplish any of these abilities in the future. Our limited operating history makes any assessment of our future success and viability subject to
significant uncertainty. In addition, if we obtain marketing approval for any of our product candidates, we will incur significant sales, marketing and manufacturing expenses. Once we are a public company, we will incur additional costs associated
with operating as a public company. As a result, we expect to continue to incur significant expenses and increasing operating losses for the foreseeable future. Because of the numerous risks and uncertainties associated with developing
pharmaceutical products, we are unable to predict the extent of any future losses or when we will become profitable, if at all. Even if we become profitable, we may not be able to sustain or increase our profitability on a quarterly or annual basis.

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The amount of our future losses is uncertain, and our quarterly operating results may fluctuate significantly or may fall below the expectations of investors or securities analysts, each of which may cause our stock price to fluctuate or decline. Our operating losses may fluctuate significantly from quarter to quarter and from year to year. We anticipate that our expenses will increase substantially if, and as, we:

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