--- title: "Sionna Therapeutics prices IPO of 10,588,233 shares at $18.00" url: "https://aibio.space/news/sionna-therapeutics-prices-ipo-10-588-233-shares-18-00/" publisher: "aibio.space (Biotech Investor Relations News)" date: "2025-02-07" section: "Financings" tickers: "NASDAQ:SION" source: "https://www.sec.gov/Archives/edgar/data/2036042/000119312525022709/d882384d424b4.htm" summary: "The offering totals $190,588,194, and the stock is approved to list on Nasdaq under SION. Proceeds to the company are $177,247,020 before expenses." --- By the aibio.space news desk. Sources - [Sionna Therapeutics, Inc. 424B4 (2025-02-07)](https://www.sec.gov/Archives/edgar/data/2036042/000119312525022709/d882384d424b4.htm) [SION](https://aibio.space/companies/sionna-therapeutics/) 2025-02-07 # Sionna Therapeutics prices IPO of 10,588,233 shares at $18.00 Tickers [SION](https://aibio.space/companies/sionna-therapeutics/) The offering totals $190,588,194, and the stock is approved to list on Nasdaq under SION. Proceeds to the company are $177,247,020 before expenses. ## Key facts - **Company**: Sionna Therapeutics, Inc. (NASDAQ: SION) - **News type**: Financings - **Primary source**: [Sionna Therapeutics, Inc. 424B4 (2025-02-07)](https://www.sec.gov/Archives/edgar/data/2036042/000119312525022709/d882384d424b4.htm) *Planning on a whiteboard. Photo: Startup Stock Photos, CC0, via StockSnap. The picture shows the field, not the companies named.* Sionna Therapeutics, Inc. priced its initial public offering of 10,588,233 shares of common stock at $18.00 per share. The final prospectus is dated February 6, 2025 and was filed on February 7, 2025 under Rule 424(b)(4), registration number 333-284352. The company's common stock is approved for listing on The Nasdaq Global Market under the symbol SION. The underwriters expect to deliver the shares on or about February 10, 2025. ## The money The offering totals $190,588,194 at the public price. Underwriting discounts and commissions are $1.26 per share, or $13,341,174 in total. Proceeds to the company before expenses are $16.74 per share, or $177,247,020. The company has granted the underwriters a 30-day option to buy up to 1,588,234 more shares at the offering price, less discounts and commissions. The prospectus estimates net proceeds of approximately $173.0 million, or approximately $199.6 million if the option is exercised in full. The company intends to use those proceeds, together with its existing cash, cash equivalents and marketable securities, to complete its ongoing Phase 1 trials, to run a planned Phase 2a proof-of-concept trial, and to fund preclinical and other early clinical work. ## The underwriters The cover lists Goldman Sachs & Co. LLC, TD Cowen, Stifel and Guggenheim Securities as the underwriters. The prospectus does not mark which of them is the lead or sole book-runner, and it does not name a placement agent or financial advisor for the deal. It does say that Goldman Sachs & Co. LLC and TD Securities (USA) LLC may release stockholders from their lock-up agreements at any time and without notice. The prospectus says the number of shares outstanding after the offering will be 42,520,700, or 44,108,934 if the option is exercised in full. That figure is based on 31,932,467 shares outstanding as of September 30, 2024, after the automatic conversion of the company's preferred stock. The prospectus says new investors face an immediate dilution in pro forma net tangible book value of $9.65 per share. ## Losses and cash The prospectus reports net losses of $47.3 million in 2023 and $40.2 million in 2022. The accumulated deficit was $165.2 million at September 30, 2024, up from $119.4 million at December 31, 2023. Since its inception the company has raised approximately $330 million from investors, including RA Capital, TPG's The Rise Fund, Atlas Venture, OrbiMed and Enavate Sciences. In March 2024 the company sold 18,628,970 shares of Series C convertible preferred stock for gross proceeds of $181.9 million. The financial statements show $38.5 million of cash and cash equivalents at December 31, 2023. The company says that amount, together with the Series C proceeds, will fund operations beyond twelve months, but the prospectus also says it will need substantial additional funding even if this offering is successful. ## The drug and its rivals Sionna is developing medicines for cystic fibrosis that aim to normalize the function of the CFTR protein. Its lead approach is an NBD1 stabilizer, to be tested in combination with a complementary modulator or as an add-on to the standard of care. The standard of care for people with the F508del mutation is Vertex's Trikafta. The prospectus also notes that Vertex received FDA approval in December 2024 for Alyftrek, a second-generation triple modulator combination. The company says at least two-thirds of patients on Trikafta do not have normal CFTR function. It says some patients reduce their Trikafta dose because of tolerability problems. Those are the company's own characterizations, not trial results. ## Safety data and next steps For SION-719 and SION-451, the prospectus reports interim Phase 1 data as of a January 14, 2025 cutoff. Both drugs were generally well tolerated at all dose levels given, with no serious adverse events, and most treatment-emergent adverse events were mild or moderate. No treatment-emergent event led to discontinuation of study drug. These are data from healthy volunteers, and the prospectus does not report efficacy in patients with cystic fibrosis. The company plans to select a lead NBD1 stabilizer after the Phase 1 trials, run a drug-drug interaction trial, and then start a Phase 2a proof-of-concept trial in CF patients. The company's risk factors say it is substantially dependent on the success of its NBD1 stabilizers. [Report an error](https://aibio.space/reputation/#correction) ## Companies in this story SION Sionna Therapeutics, Inc. 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Cite as: aibio.space, "Sionna Therapeutics prices IPO of 10,588,233 shares at $18.00", 2025-02-07, https://aibio.space/news/sionna-therapeutics-prices-ipo-10-588-233-shares-18-00/