STOCK TITAN

Sionna Therapeutics (Nasdaq: SION) posts Q2 2026 loss, cash of $268.3M

(Moderate)
(Neutral)
Form Type
8-K

Rhea-AI Filing Summary

Sionna Therapeutics, Inc. reported second quarter 2026 results and provided an update on its cystic fibrosis pipeline. Research and development expenses were $21.9 million and general and administrative expenses were $10.6 million, resulting in a net loss of $29.9 million, or $0.66 per share for the quarter.

The company reported $268.3 million in cash, cash equivalents and marketable securities as of June 30, 2026 and expects this cash position to fund operations into 2028. Pipeline highlights include the PreciSION CF Phase 2a proof-of-concept trial of NBD1 stabilizer SION-719 as an add-on to standard of care and a Phase 1 dual combination trial of SION-451 with SION-2222 and SION-109, both on track for topline data in summer 2026. Sionna also presented encore clinical and nonclinical data on its NBD1 stabilizers at major cystic fibrosis conferences.

Positive

  • None.

Negative

  • None.

Filing Explained

June 30 liquidity was $268.3 million; the balance sheet also reported $205,348 thousand of working capital and $265,775 thousand of equity.

This Form 8-K furnishes the company’s second-quarter results and business update; its disclosed structural consequence is a reported liquidity, working-capital, and equity position as of June 30, 2026.

A Form 8-K reports specified material events within four business days; here, Item 2.02 furnishes the results and Exhibit 99.1 is the related press release.

The balance sheet lists cash, cash equivalents and marketable securities of $268,253 thousand at June 30, versus $310,302 thousand at December 31, 2025; working capital was $205,348 thousand and stockholders’ equity was $265,775 thousand.

Item 2.02 Results of Operations and Financial Condition Financial
Disclosure of earnings results, typically an earnings press release or preliminary financials.
Item 9.01 Financial Statements and Exhibits Exhibits
Financial statements, pro forma financial information, and exhibit attachments filed with this report.
Research and development expenses Q2 2026 $21.9 million For the second quarter ended June 30, 2026
General and administrative expenses Q2 2026 $10.6 million For the second quarter ended June 30, 2026
Net loss Q2 2026 $29.9 million For the second quarter ended June 30, 2026
Net loss per share Q2 2026 $0.66 Basic and diluted net loss per share for the quarter ended June 30, 2026
Cash, cash equivalents and marketable securities $268.3 million Balance as of June 30, 2026
Phase 2a proof-of-concept trial medical
"The PreciSION CF Phase 2a proof-of-concept (POC) trial is evaluating SION-719"
NBD1 stabilizer medical
"clinical NBD1 stabilizer programs during the second quarter as we approach"
An nbd1 stabilizer is a drug-like molecule designed to strengthen a specific structural region (NBD1) of a disease-related protein so the protein folds and works more reliably. For investors, these compounds matter because successful stabilization can turn a malfunctioning protein into a working one, creating therapeutic benefit, driving clinical progress, and potentially increasing the commercial value of a drug program much like fixing a critical part can restore a machine’s performance.
CFTR modulators medical
"complementary CFTR modulators that are designed to work synergistically"
F508del genetic mutation medical
"engineered to correct the defects caused by the F508del genetic mutation"
working capital financial
"Sionna defines working capital as current assets minus current liabilities"
Working capital is the money a business has available to cover its daily expenses, like paying bills and buying supplies. It’s like the cash in your wallet that helps you handle everyday costs; having enough ensures the business can operate smoothly without running into money shortages.
Regulation FD regulatory
"for complying with its disclosure obligations under Regulation FD"
Regulation FD is a rule that prevents company insiders, like executives, from sharing important information with some people before others get it. It matters because it helps ensure all investors have equal access to key news, making the stock market fairer and reducing chances of insider trading.
Research and development expenses Q2 2026 $21.9 million compared to $15.4 million in the second quarter of 2025
General and administrative expenses Q2 2026 $10.6 million compared to $6.5 million in the second quarter of 2025
Net loss Q2 2026 $29.9 million compared to $18.1 million in the second quarter of 2025
Net loss per share Q2 2026 $0.66 compared to $0.41 in the second quarter of 2025
Cash, cash equivalents and marketable securities $268.3 million as of June 30, 2026
Guidance

Sionna expects its current cash position to fund operations into 2028.

AI-generated analysis. How Rhea-AI works. Not financial advice.

See more from StockTitan in Google Search and AI answers. Adds StockTitan as a preferred source · opens Google
Add on Google
Learn about SEC filing dates

FAQ

What were Sionna Therapeutics (SION) key financial results for Q2 2026?

Sionna reported Q2 2026 research and development expenses of $21.9 million, general and administrative expenses of $10.6 million, and a net loss of $29.9 million, or $0.66 per share, compared with a net loss of $18.1 million in Q2 2025.

How much cash does Sionna Therapeutics (SION) have, and how long is the runway?

As of June 30, 2026, Sionna held $268.3 million in cash, cash equivalents and marketable securities. The company expects its current cash position to fund operations into 2028, supporting ongoing clinical trials and corporate activities.

What is the status of Sionna Therapeutics (SION) PreciSION CF Phase 2a trial with SION-719?

The PreciSION CF Phase 2a proof-of-concept trial evaluates NBD1 stabilizer SION-719 as an add-on to standard of care in cystic fibrosis participants. It assesses safety, tolerability, pharmacokinetics and CFTR function via sweat chloride, with topline data on track for summer 2026.

What is Sionna Therapeutics (SION) Phase 1 dual combination trial evaluating?

The Phase 1 trial evaluates NBD1 stabilizer SION-451 in proprietary dual combinations with SION-2222 and SION-109 in healthy volunteers. These combinations target different CFTR domains, and topline data are expected in summer 2026.

What data did Sionna Therapeutics (SION) present at recent cystic fibrosis conferences?

Sionna presented encore clinical and nonclinical data on NBD1 stabilizers SION-719 and SION-451 at the 49th European Cystic Fibrosis Conference. Nonclinical results showed NBD1 stabilizers could increase F508del-CFTR protein half-life up to wild-type levels, alone or with complementary CFTR modulators.

What is Sionna Therapeutics (SION) overall strategy in cystic fibrosis treatment?

Sionna is a clinical-stage biopharmaceutical company focused on normalizing CFTR function in cystic fibrosis. Its strategy centers on directly stabilizing CFTR’s NBD1 domain and combining NBD1 stabilizers with complementary CFTR modulators to potentially deliver differentiated, more normal CFTR function.
0002036042FALSE00020360422026-08-062026-08-06

UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
__________________________
FORM 8-K
__________________________
CURRENT REPORT
Pursuant to Section 13 or 15(d)
of the Securities Exchange Act of 1934
Date of Report (date of earliest event reported): August 06, 2026
__________________________
SIONNA THERAPEUTICS, INC.
(Exact name of registrant as specified in its charter)
__________________________
Delaware001-4250484-2801521
(State or other jurisdiction
of incorporation)
(Commission
File Number)
(I.R.S. Employer
Identification No.)
SIONNA THERAPEUTICS, INC.
21 Hickory Drive, Suite 500
Waltham, MA02451
(Address of principal executive offices, including zip code)
617-819-2020
(Registrant’s telephone number, including area code)
Not Applicable
(Former Name or Former Address, if Changed Since Last Report)
__________________________
Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:
Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)
Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)
Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))
Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))
Securities registered pursuant to Section 12(b) of the Act:
Title of each classTrading
Symbol(s)
Name of each exchange
on which registered
Common Stock, $0.001 par value per shareSIONThe Nasdaq Global Market
Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§ 230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§ 240.12b-2 of this chapter).
Emerging growth company x
If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. o



Item 2.02    Results of Operations and Financial Condition.
On August 6, 2026, Sionna Therapeutics, Inc. issued a press release announcing its financial results and business highlights for the quarter ended June 30, 2026. The full text of the press release is furnished as Exhibit 99.1 to this Current Report on Form 8-K.
The information set forth under this Item 2.02 and in Exhibit 99.1 attached hereto is intended to be furnished and shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities of that section, nor shall it be deemed incorporated by reference in any filing under the Securities Act of 1933 or the Exchange Act, except as expressly set forth by specific reference in such filing.
Item 9.01    Financial Statements and Exhibits.
(d) Exhibits
99.1
Press Release of Sionna Therapeutics, Inc. dated August 6, 2026.
104Cover Page Interactive Data File (embedded within the Inline XBRL document).



SIGNATURE
Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.
Sionna Therapeutics, Inc.
Date: August 06, 2026
By:/s/ Jennifer Fitzpatrick
Name:Jennifer Fitzpatrick
Title:Chief Legal Officer


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 (CF) today reported financial results for the second quarter ended June 30, 2026, and provided a business update.

“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 Executive Officer of Sionna. “We remain focused on execution 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 2026, 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 (galicaftor), a transmembrane domain 1 (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 2026, 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 16th Australasian Cystic Fibrosis Conference taking place August 7th-9th in Geelong, Australia.

Financial Results for the Quarter Ended June 30, 2026

Research and Development Expenses: Research and development expenses were $21.9 million for the second quarter of 2026, compared to $15.4 million for the second quarter of 2025. These increases were



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 operational activities.

General and Administrative Expenses: General and administrative expenses were $10.6 million for the second quarter of 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 $268.3 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 conductance regulator (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 Sionna believes 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 CFTR modulators 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 to following Sionna’s press releases, SEC filings, public conference calls, presentations, and webcasts.
Cautionary Note Regarding Forward-Looking Statements
This 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 meaningful benefit 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 the timing 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 predict later 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 press release are based on management’s current expectations and beliefs and are subject to a number of risks, uncertainties and important



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 and uncertainties 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 earlier nonclinical 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, including existing 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 Securities and 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



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
$
21,864 
$
15,383 
$
40,827 
$
29,051 
General and administrative
10,606 
6,523 
21,242 
12,514 
Total operating expenses
32,470 
21,906 
62,069 
41,565 
Loss from operations
(32,470)
(21,906)
(62,069)
(41,565)
Other income:
Interest income
2,587 
3,667 
5,407 
6,667 
Other income (expense), net
(3)
171 
(3)
348 
Total other income
2,584 
3,838 
5,404 
7,015 
Net loss
$
(29,886)
$
(18,068)
$
(56,665)
$
(34,550)
Net loss per share, basic and diluted
$
(0.66)
$
(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 


Sionna Therapeutics, Inc.
Selected Consolidated Balance Sheet Data
(In thousands)
(Unaudited)
June 30,
December 31,
2026
2025
Cash, cash equivalents, and marketable securities
$
268,253 
$
310,302 
Working capital1
205,348 
229,707 
Total assets
283,249 
325,953 
Total stockholders’ equity
265,775 
306,833 
1Sionna defines working capital as current assets minus current liabilities.


Filing Exhibits & Attachments

4 documents