Earnings release
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Sionna Therapeutics Reports Second Quarter 2026 Financial Results PreciSION CF Phase 2a proof - of - concept trial evaluating NBD1 stabilizer SION - 719 as an add - on to standard of care is on track for topline data summer of 2026 Phase 1 trial evaluating NBD1 stabilizer SION - 451 in proprietary dual combinations with SION - 2222 and with SION - 109 also is on track for topline data summer of 2026 Maintained strong cash position with $ 268.3 million in cash and cash equivalents , expected to fund operations into 2028 WALTHAM , Mass . , Aug 6 , 2026 GLOBE NEWSWIRE ) - Sionna Therapeutics , Inc. ( Nasdaq SION ) , a clinical - stage biopharmaceutical company on a mission to revolutionize the current treatment paradigm for cystic fibrosis ( financial results for the second quarter ended June 30 , 202 , and provided a business update . CF ) today reported " We continued to advance our clinical NBD1 stabilizer programs during the second quarter as we approach two important clinical milestones this summer , " said Mike Cloonan , President and Chief E ecutive Officer of Sionna . " We remain focused on e ecution and delivering topline data from both our Phase 2a proof - of - concept trial and our Phase 1 dual combination trial . Together , these studies have the potential to further validate our core belief that directly stabilizing NBD1 is central to restoring CFTR function and transforming the treatment paradigm for people living with cystic fibrosis . " Pipeline Updates • • • ( PreciSION CF Phase 2a Proof - of - Concept Trial with SION - 719 Is On Track : The PreciSION CF Phase 2a proof - of - concept POC ) trial ( NCT07108153 ) is evaluating SION - 719 as an add - on to standard of care ( SOC ) in CF participants . The trial is evaluating the safety , tolerability , and pharmacokinetics ( PK ) of SION - 719 when administered with SOC and assessing change in CFTR function as measured by sweat chloride levels . In April 202 , Sionna announced it had completed enrollment . Topline data from this trial are on track for this summer . Phase 1 Dual Combination Trial with SION - 451 and Complementary Modulators Is On Track : The Phase 1 trial ( NCT07035990 ) is evaluating SION - 451 in proprietary dual combinations with SION - 2222 ( transmembrane domain 1 ( ( galicaftor ) , a TMD1 ) -directed CFTR corrector , and with SION - 109 , an intracellular loop 4 ICL4 ) -directed CFTR corrector , in healthy volunteers . Topline data from this trial are on track for this summer . Presented Encore Data at 49th European Cystic Fibrosis Conference : In June 202 , Sionna presented encore clinical and nonclinical data at the 49th European Cystic Fibrosis Conference ( ECFS ) in Lisbon , Portugal . Presentations highlighted previously reported Phase 1 data for the Company's clinical - stage NBD1 stabilizers , SION - 719 and SION - 451 , and nonclinical data demonstrating the potential of NBD1 stabilizers to increase F508del - CFTR protein half - life up to wild - type levels when used alone or in combination with complementary CFTR modulators . The same data will also be presented at the 1 th Australasian Cystic Fibrosis Conference taking place August 7th - 9th in Geelong , Australia . Financial Results for the Quarter Ended June 30 , 202 Research and Development Expenses : Research and development e 202 , compared to $ 15.4 million for the second quarter of 2025. These increases were penses were $ 21.9 million for the second quarter of
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mainly driven by development expenses to support the advancement of Sionna’s clinical pipeline and personnel-related costs, including stock-based compensation expenses, to support the Company’s continued growth and operationalactivities. General and Administrative Expenses: General and administrative expenses were $10.6 million for the second quarterof 2026 , compared to $6 .5 million for the second quarter of 2025. These increases were primarily due to personnel-related costs, including stock-based compensation expenses, to support the Company’s continued growth and operational activities. Net Loss: Net loss was $29.9 million for the second quarter of 2026 , compared to a net loss of $18.1 million for the second quarter of 2025. Cash and Cash Equivalents: Cash, cash equivalents and marketable securities totaled $26 8.3 million as of June 30, 2026 . Sionna expects its current cash position to fund operations into 2028. About Sionna Therapeutics Sionna Therapeutics is a clinical-stage biopharmaceutical company on a mission to revolutionize the current treatment paradigm for cystic fibrosis ( CF) by developing novel medicines that normalize the function of the cystic fibrosis transmembrane conductanceregulator ( CFTR) protein. Sionna’s goal is to deliver differentiated medicines for people living with CF that can restore their CFTR function to as close to normal as possible by directly stabilizing CFTR’s nucleotide binding domain 1 ( NBD1), which Sionnabelieves is central to potentially unlocking dramatic improvements in clinical outcomes and quality of life for people with CF. Leveraging more than a decade of the co-founders’ research on NBD1, Sionna is advancing a pipeline of small molecules engineered to correct the defects caused by the F508del genetic mutation, which occurs in NBD1. Sionna is also developing a portfolio of complementary CFTRmodulators that are designed to work synergistically with its NBD1 stabilizers to improve CFTR function. For more information about Sionna, visit www.sionnatx.com. Sionna intends to use its Investor Relations website as a means of disclosing material nonpublic information and for complying with its disclosure obligations under Regulation FD. Accordingly, investors should monitor Sionna’s Investor Relations website, in addition tofollowing Sionna’s press releases, SEC filings, public conference calls, presentations, and webcasts. Cautionary Note Regarding Forward-Looking StatementsThis press release contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995, as amended, including, without limitation, implied and express statements about Sionna’s beliefs and expectations regarding: its goal of transforming the treatment paradigm for CF and providing clinically meaningfulbenefit for CF participants; the potential of Sionna’s product candidates to expand therapeutic options for people with CF; the initiation, timing, progress and results of Sionna’s research and development programs, clinical trials and studies, including thetiming of topline data from Sionna’s Phase 2a proof-of-concept trial and Phase 1 dual combination trial; the ability of clinical trials to demonstrate safety and efficacy of Sionna’s product candidates; the ability of Sionna’s nonclinical studies or earlier clinical trials to predictlater clinical trial results; and financial projections and expectations regarding the time period in which Sionna’s capital resources will be sufficient to fund its anticipated operations, including cash runway, use of capital, expenses and other financial results. In some cases, the forward-looking statements can be identified by terms such as “may,” “will,” “should,” “would,”“expect,” “plan,” “anticipate,” “could,” “intend,” “target,” “project,” “believe,” “estimate,” “predict,” “potential” or “continue” or the negative of these terms or other similar expressions. Any forward-looking statements in this pressrelease are based on management’s current expectations and beliefs and are subject to a number of risks, uncertainties and important
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factors that may cause actual events or results to differ materially from those expressed or implied by the forward- looking statements contained in this press release. Factors that could cause actual results to differ include, but are not limited to, risks anduncertainties inherent in the development of product candidates, including uncertainties concerning the initiation, timing, progress, and results of Sionna’s ongoing, planned and future clinical trials and studies; the Company’s ability to replicate positive results from earliernonclinical studies or clinical trials in current or future clinical trials; Sionna’s ability to demonstrate that its NBD1 stabilizers, complementary CFTR modulators, and any potential future product candidates are safe and effective for their proposed indications; regulatory developments in the United States and foreign countries; the competitive landscape for CF treatments, includingexisting therapies; and general economic, industry and market conditions. These risks and uncertainties are described in the section entitled “Risk Factors” in Sionna’s most recent Annual Report on Form 10-K as well as any subsequent filings with the Securitiesand Exchange Commission. The events and circumstances reflected in the forward-looking statements may not be achieved or occur. In addition, any forward-looking statements represent Sionna’s views only as of today and should not be relied upon as representing its views as of any subsequent date. Sionna explicitly disclaims any obligation to update any forward-looking statements except as required by law. No representations or warranties ( expressed or implied) are made about the accuracy of any such forward-looking statements. Investor Contact Juliet Labadorf ir@sionnatx.com Media Contact Sarah Spencer media@sionnatx.com
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Sionna Therapeutics, Inc. Consolidated Statements of Operations (In thousands, except per share data) (Unaudited) Three Months Ended Six Months Ended June 30, June 30, 2026 2025 2026 2025 Operating expenses: Research and development $ 21,86 4 $ 15,383 $ 40,827 $ 29,051 General and administrative 10,6 06 6 ,523 21,242 12,514 Total operating expenses 32,470 21,906 6 2,06 9 41,5 5 Loss from operations ( 32,470) ( 21,906 ) ( 6 2,06 9) ( 41,5 5) Other income: Interest income 2,587 3,6 6 7 5,407 , 7 Other income( expense), net ( 3) 171 ( 3) 348 Total other income 2,584 3,838 5,404 7,015 Net loss $( 29,886 ) $( 18,06 8) $( 56 ,6 6 5) $( 34,550) Net loss per share, basic and diluted $ ( 0.6 6 ) $ ( 0.41) $ ( 1.25) $ ( 0.98) Weighted-average common shares outstanding, basic and diluted 45,148,971 44,116 ,997 45,306 ,105 35,404,928
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Sionna Therapeutics, Inc. Selected Consolidated Balance Sheet Data (In thousands) (Unaudited) June 30, December 31, 2026 2025 Cash, cash equivalents, and marketable securities $ 26 8,253 $ 310,302 Working capital 205,348 229,707 Total assets 283,249 325,953 Total stockholders’ equity 26 5,775 306 ,833 Sionna defines working capital as current assets minus current liabilities. 1 1