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Atossa Therapeutics (ATOS) deepens Q1 2026 loss while expanding (Z)-endoxifen pipeline

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(Moderate)
Filing Sentiment
(Neutral)
Form Type
8-K

Rhea-AI Filing Summary

Atossa Therapeutics reported a larger net loss for the first quarter of 2026 as it invested more heavily in its (Z)-endoxifen programs in oncology and rare diseases. Net loss was $9.6 million, compared with $6.7 million a year earlier, with net loss per share widening to $1.11 from $0.78. Total operating expenses rose to $9.9 million, driven by higher clinical trial spending and legal costs tied to patent litigation and intellectual property work. Cash and cash equivalents were $31.7 million as of March 31, 2026, with no debt reported. During the quarter, Atossa secured FDA Orphan Drug and Rare Pediatric Disease designations for (Z)-endoxifen in Duchenne Muscular Dystrophy and an additional Rare Pediatric Disease designation in McCune-Albright Syndrome, while highlighting encouraging preclinical data in dystrophic mouse models and expanding its clinical leadership team.

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Insights

Atossa increased R&D and legal spending, deepening losses while advancing (Z)-endoxifen and strengthening rare-disease positioning.

Atossa Therapeutics is still pre-revenue and posted a Q1 2026 net loss of $9.6M versus $6.7M a year earlier as operating expenses climbed to $9.9M. Higher clinical trial costs and legal fees for patent litigation and IP work were the main drivers.

R&D spending reached $4.8M, mainly for (Z)-endoxifen trials, while G&A rose to $5.1M on a $1.8M increase in legal expenses that management notes relate to ongoing patent litigation that has since been settled. Cash and equivalents were $31.7M with total liabilities of $7.5M, suggesting a debt-light balance sheet but continued cash burn.

Strategically, the quarter added FDA Orphan Drug and Rare Pediatric Disease designations in Duchenne Muscular Dystrophy and Rare Pediatric Disease designation in McCune-Albright Syndrome, which may qualify a future approval for a Priority Review Voucher. The claimed preclinical efficacy signals in DMD models and new medical directors in breast oncology and rare diseases support the (Z)-endoxifen focus, while actual value depends on later-stage clinical results and regulatory outcomes described in future periods.

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.
Net loss $9,589,000 For the three months ended March 31, 2026
Net loss prior year $6,718,000 For the three months ended March 31, 2025
Total operating expenses $9,870,000 For the three months ended March 31, 2026
Research and development expenses $4,779,000 For the three months ended March 31, 2026
General and administrative expenses $5,091,000 For the three months ended March 31, 2026
Cash and cash equivalents $31,718,000 As of March 31, 2026
Net loss per share $1.11 Basic and diluted, Q1 2026
Shares outstanding 8,611,361 shares Common stock issued and outstanding as of March 31, 2026
Orphan Drug Designation regulatory
"the FDA Office of Orphan Products Development (OOPD) granted Orphan Drug Designation to (Z)-endoxifen for the treatment of DMD"
Orphan drug designation is a special status given to medicines developed to treat rare diseases affecting only a small number of people. This status often provides benefits like faster approval processes and financial incentives, making it more attractive for companies to develop these drugs. For investors, it signals potential for exclusive market rights and reduced competition, which can impact the drug’s profitability.
Rare Pediatric Disease designation regulatory
"the Company previously received Rare Pediatric Disease (RPD) designation for (Z)-endoxifen for the treatment of DMD"
A rare pediatric disease designation is an official regulatory status given to a drug or therapy that targets a serious or life‑threatening condition primarily affecting children and is uncommon in the population. It matters to investors because the status often brings financial and development perks — such as tax credits, reduced fees, faster review and periods of market protection — which can lower costs, speed approval and improve the commercial outlook; think of it as a VIP pass that makes bringing a scarce, child‑focused treatment to market easier and potentially more profitable.
Priority Review Voucher regulatory
"drugs with RPD designation may be eligible for a Priority Review Voucher (PRV), which can be used to obtain priority review"
A priority review voucher is a transferable regulatory incentive that lets a company move a future drug or device application to the front of the review line, shortening the review period by several months. For investors it matters because the voucher can speed up market access for a high-value product or be sold to other companies for significant cash, acting like a tradable fast-pass that can accelerate revenue or create immediate financial upside.
Selective Estrogen Receptor Modulator/Degrader medical
"(Z)-Endoxifen is a potent Selective Estrogen Receptor Modulator/Degrader (SERM/D) with demonstrated activity"
A selective estrogen receptor modulator/degrader (SERM/SERD) is a drug that targets the estrogen receptor in the body and either blocks its action in some tissues or causes the receptor to be removed. Think of it like a dimmer switch or a targeted cleaner that turns down or takes away a specific control knob rather than shutting down the whole system; for investors this matters because these drugs can treat hormone-driven diseases, drive sales or licensing value, and are sensitive to clinical trial results, approvals and competing therapies.
McCune-Albright Syndrome medical
"Rare Pediatric Disease designation from the FDA for McCune-Albright Syndrome"
A rare genetic disorder that causes certain patches of the body to develop abnormal bone growth, hormonal imbalances, and distinctive skin markings because a mutation affects only some cells. For investors, it matters because small, well-defined patient groups can create opportunities for specialized drugs and diagnostic tests with faster regulatory paths and premium pricing, similar to how a custom tool can be valuable despite serving a narrow niche.
Duchenne Muscular Dystrophy medical
"Orphan Drug and Rare Pediatric Disease designations from the FDA for (Z)-endoxifen in DMD"
A rare, inherited condition that progressively weakens muscles, Duchenne muscular dystrophy causes the body’s muscle fibers to break down over time, often leading to severe disability. For investors, it matters because the small, well-defined patient population, high unmet medical need and complex regulatory and pricing dynamics mean successes or failures in clinical trials, approvals, or therapies can have outsized effects on a company’s valuation and future revenue prospects.
Net loss $9,589,000
Total operating expenses $9,870,000
Research and development expenses $4,779,000 15% increase year over year
General and administrative expenses $5,091,000 56% increase year over year
Cash and cash equivalents $31,718,000
0001488039false00014880392026-05-082026-05-08

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): May 8, 2026

Atossa Therapeutics, Inc.

(Exact name of Registrant as Specified in Its Charter)

Delaware

001-35610

26-4753208

(State or Other Jurisdiction
of Incorporation)

(Commission File Number)

(IRS Employer
Identification No.)

1448 NW Market Street, Suite 500

Seattle, Washington

98107

(Address of Principal Executive Offices)

(Zip Code)

Registrant’s Telephone Number, Including Area Code: (206) 588-0256

N/A

(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 class

Trading
Symbol(s)


Name of each exchange on which registered

Common Stock, $0.18 par value

ATOS

The Nasdaq Capital 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

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. ☐



 

Item 2.02. Results of Operations and Financial Condition.

 

On May 8, 2026, Atossa Therapeutics, Inc. (the “Company”) issued a press release announcing the first quarter ended March 31, 2026 financial results and providing a Company update. A copy of the press release is attached as Exhibit 99.1 to this Current Report on Form 8-K and is incorporated herein by reference.

 

The information in Items 2.02 and 9.01 of this report, including Exhibit 99.1 attached hereto, shall not be deemed to be filed for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or otherwise subject to the liabilities of that Section or Sections 11 and 12(a)(2) of the Securities Act of 1933, as amended. The information contained herein and in the accompanying exhibit shall not be incorporated by reference into any filing with the U.S. Securities and Exchange Commission made by the Company, whether made before or after the date hereof, regardless of any general incorporation language in such filing.

 

 

Item 9.01. Financial Statements and Exhibits.

(d) Exhibits

 

 

 

Exhibit No.

 

Description

99.1

 

Press Release dated May 8, 2026

 

 

 

104

 

Cover page Interactive Data File (embedded within the Inline XBRL document)

* * *


SIGNATURES

 

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

Atossa Therapeutics, Inc.

Date:

May 8, 2026

By:

/s/ Mark J. Daniel

Mark J. Daniel
Chief Financial Officer

(Principal Financial and Accounting Officer)


 

Exhibit 99.1

 

img248274862_0.jpg

Atossa Therapeutics Reports First Quarter 2026 Financial Results and Provides a Corporate Update

SEATTLE, WASHINGTON, May 8, 2026 — Atossa Therapeutics, Inc. (Nasdaq: ATOS) (Atossa or the Company), a clinical-stage biopharmaceutical company developing novel therapies in oncology and other areas of high unmet clinical need, today announces its financial results and provides an update on recent corporate developments for the first quarter ended March 31, 2026.

 

“During the quarter, we made meaningful progress advancing our (Z)-endoxifen development strategy across both oncology and rare disease indications,” stated Dr. Steven Quay, M.D., Ph.D., Atossa Therapeutics’ President and Chief Executive Officer. “We continued to advance (Z)-endoxifen in the clinic for the treatment of breast cancer, while also generating data to support its potential in rare diseases, including Duchenne Muscular Dystrophy (DMD) and McCune-Albright Syndrome. Importantly, we secured both Orphan Drug and Rare Pediatric Disease designations from the FDA for (Z)-endoxifen in DMD, and subsequently we’ve received Rare Pediatric Disease designation from the FDA for McCune-Albright Syndrome, reinforcing the potential of our programs in areas of high unmet need. Building on this momentum, we remain focused on identifying additional indications where our platform can deliver meaningful therapeutic benefit to patients with limited treatment options.”

Dr. Quay continued, “Our balance sheet remains strong, positioning us to continue to execute across our strategic plans, and deliver value to shareholders in upcoming quarters.”

 

First Quarter 2026 & Recent Highlights

 

Atossa Therapeutics Presented Encouraging Pre-clinical data for (Z)-Endoxifen in DMD at the MDA Clinical & Scientific Conference - In an oral presentation on March 11, 2026, the Company demonstrated that (Z)-endoxifen improved muscle strength, increased lean mass, and reduced biochemical markers of muscle damage in dystrophic mouse models. We believe these data support advancement into the clinical setting.

Atossa Therapeutics Received FDA Orphan Drug Designation for (Z)-Endoxifen for the Treatment of DMD - In January 2026, Atossa announced that the U.S. Food and Drug Administration (FDA) Office of Orphan Products Development (OOPD) granted Orphan Drug Designation to (Z)-endoxifen for the treatment of DMD. Orphan Drug Designation is granted by the FDA to therapies intended to treat rare diseases or conditions. The designation is designed to encourage drug development by offering certain potential incentives, such as regulatory support and, if the product ultimately receives marketing approval for the designated indication, eligibility for a period of market exclusivity. The Company previously received Rare Pediatric Disease (RPD) designation for (Z)-endoxifen for the treatment of DMD.

 

Atossa Therapeutics Received FDA RPD Designation for (Z)-Endoxifen for McCune-Albright Syndrome – In early May 2026, Atossa announced that the FDA had granted RPD for (Z)-Endoxifen for McCune-Albright Syndrome, which is the Company’s second of such designations received in the last 6 months for rare diseases with currently unmet need. Upon approval of a qualifying marketing application, drugs with RPD designation may be eligible for a Priority Review Voucher (PRV), which can be used to obtain priority review for a future application or may be sold or transferred to another sponsor. In the last 18 to 24 months, disclosed PRV sales have ranged from $100–$205 million.

 

Atossa Therapeutics Strengthened Clinical Leadership Team with the Addition of Two Experienced Biopharma Executives - Atossa announced the engagement of Kathy Puyana Theall, M.D. as Medical Director - Breast Oncology, and Adebola Giwa, M.D. as Medical Director - Rare Diseases. We believe the addition of these two highly experienced physicians and clinical leaders meaningfully strengthens Atossa’s ability to execute on its (Z)-endoxifen development strategy across both breast cancer and rare disease programs, including DMD and McCune-Albright Syndrome, as the Company advances toward key clinical and regulatory milestones.

 

 


 

Financial Results for the First Quarter Ended March 31, 2026

Operating Expenses. Total operating expenses were $9.9 million for the three months ended March 31, 2026, which was an increase of $2.5 million, from total operating expenses for the three months ended March 31, 2025 of $7.4 million. Factors contributing to the increased operating expenses in the three months ended March 31, 2026 are explained below.

Research & Development (R&D) Expenses. The following table provides a breakdown of major categories within R&D expenses for the three months ended March 31, 2026 and 2025, together with the dollar change and percentage change in those categories (dollars in thousands):



 

 

 

For the Three Months Ended March 31,

 

 

 

 

 

 

 

 

2026

 

 

2025

 

 

Increase (Decrease)

 

 

% Increase (Decrease)

Research and Development Expenses

 

 

 

 

 

 

 

 

 

 

 

 

Clinical and pre-clinical trials

 

$

3,718

 

 

$

2,747

 

 

$

971

 

 

35%

Compensation

 

 

934

 

 

 

880

 

 

 

54

 

 

6%

Professional fees and other

 

 

127

 

 

 

530

 

 

 

(403

)

 

(76)%

Research and Development Expenses Total

 

$

4,779

 

 

$

4,157

 

 

$

622

 

 

15%

 

As (Z)-endoxifen is our only product candidate for which we currently incur R&D expenses, we have not further disaggregated R&D expenses by product candidate:

 

Clinical and non-clinical trial expenses increased $1.0 million for the three ended March 31, 2026, compared to the three months ended March 31, 2025, due to increases in spend related to our (Z)-endoxifen trials, including drug development costs.

 

The increase in R&D compensation expenses of $0.1 million for the three months ended March 31, 2026 compared to the three months ended March 31, 2025, was due primarily to increases in non-cash stock-based compensation expense of $0.1 million.

 

The decreases in R&D professional fees and other of $0.4 million for the three months ended March 31, 2026, compared to the three months ended March 31, 2025, were primarily attributable to lower regulatory consulting fees in the first quarter of 2026 related to our (Z)-endoxifen program as compared to the same quarter in the prior year.
 

General and Administrative (G&A) Expenses. The following table provides a breakdown of major categories within G&A expenses for the quarter ended March 31, 2026 and 2025, together with the dollar change and percentage change in those categories (dollars in thousands):

 

 

 

 

For the Three Months Ended March 31,

 

 

 

 

 

 

 

 

2026

 

 

2025

 

 

Increase (Decrease)

 

 

% Increase (Decrease)

General and Administrative Expenses

 

 

 

 

 

 

 

 

 

 

 

 

Compensation

 

$

1,311

 

 

$

1,462

 

 

$

(151

)

 

(10)%

Professional fees and other

 

 

3,780

 

 

 

1,795

 

 

 

1,985

 

 

111%

General and Administrative Expenses Total

 

$

5,091

 

 

$

3,257

 

 

$

1,834

 

 

56%

 

The decrease in G&A compensation expenses of $0.2 million for the three months ended March 31, 2026, compared to the three months ended March 31, 2025, was due primarily to a decrease in headcount in the current year period compared to the same period in the prior year.

 

The increase in G&A professional fees and other of $2.0 million for the three months ended March 31, 2026, compared to the three months ended March 31, 2025, was due primarily to higher legal fees of $1.8 million, related to our ongoing patent

 


 

litigation activity, which has subsequently been settled, as well as fees associated with management of our intellectual property portfolio and other legal matters.

 

Interest Income. Interest income of $0.3 million for the quarter ended March 31, 2026 represented a decrease of $0.4 million compared to the prior year period. The decrease was due primarily to lower average cash balances invested in our money market account during the current year period relative to the same period in the prior year.

 

About Atossa Therapeutics

 

Atossa Therapeutics, Inc. (Nasdaq: ATOS) is a clinical-stage biopharmaceutical company developing innovative medicines in oncology and other areas of significant unmet need. The Company’s lead product candidate, (Z)-endoxifen, is currently in development across several clinical settings.

 

(Z)-Endoxifen is a potent Selective Estrogen Receptor Modulator/Degrader (SERM/D) with demonstrated activity across multiple mechanisms of interest. Atossa is evaluating its potential applications in oncology and rare diseases. The Company’s proprietary oral formulation has shown a favorable safety profile and pharmacology distinct from tamoxifen, including ER-targeted effects and PKC inhibition. Atossa’s (Z)-endoxifen is not approved for any indication.

 

Atossa has received Orphan Drug Designation from the U.S. Food and Drug Administration (FDA) for (Z)-endoxifen for the treatment of Duchenne Muscular Dystrophy, as well as Rare Pediatric Disease (RPD) designation for (Z)-endoxifen for the treatment of both Duchenne Muscular Dystrophy and McCune-Albright Syndrome. Upon approval of a qualifying marketing application, drugs with RPD designation may be eligible for a Priority Review Voucher (PRV), which can be used to obtain priority review for a future application or may be sold or transferred to another sponsor. In the last 18–24 months, disclosed PRV sales have ranged from $100–$205 million.

 

Atossa’s (Z)-endoxifen program is supported by a growing global intellectual property portfolio, including multiple recently issued U.S. patents and numerous pending applications worldwide.

 

More information is available at https://atossatherapeutics.com.

 

Forward Looking Statements

 

This press release contains certain “forward-looking statements” within the meaning of applicable securities laws, including but not limited to, our 2026 outlook and our expectations regarding the Company’s development and regulatory strategy and related milestones, the potential indications that the Company may pursue for (Z)-endoxifen, the potential for (Z)-endoxifen to receive regulatory approval and the timing thereof, the Company's progress across its pipeline and potential commercialization, the strength of the Company's patent portfolio, the Company’s potential eligibility for and the value of a Rare Pediatric Disease Priority Review Voucher (PRV), and the potential market and growth opportunities for the Company. Words such as “expect,” “potential,” “continue,” “may,” “will,” “should,” “could,” “would,” “seek,” “intend,” “plan,” “estimate,” “anticipate,” “believe,” “design,” “predict,” “future,” or other similar expressions or statements regarding intent, belief or current expectations, are forward-looking statements.

Forward-looking statements in this press release are subject to risks and uncertainties that may cause actual results, outcomes, or the timing of actual results or outcomes to differ materially from those projected or anticipated, including, without limitation, risks and uncertainties associated with: our ability to successfully execute our strategy to shorten our clinical development timelines and pursue a DMD or McCune-Albright Syndrome indication or other indications for our lead program, (Z)-endoxifen; expected timing, completion and results of our preclinical studies, clinical trials, and research and development programs; the unpredictable relationship between preclinical study results and clinical study results; the timing or likelihood of regulatory filings and approvals; the outcome or timing of necessary regulatory approvals; our ability to receive orphan-drug exclusivity for (Z)-endoxifen for DMD; our ability to maintain compliance with Nasdaq listing requirements; our ability to establish and maintain intellectual property rights covering our products; the impact of general macroeconomic conditions on our business; our ability to raise capital; and other risks and uncertainties detailed from time to time in Atossa’s filings with the SEC, including, without limitation, its Annual Reports on Form 10-K and Quarterly Reports on Form 10-Q.

The market value of a PRV is variable and subject to a number of factors beyond our control and reported past PRV sale amounts are not necessarily indicative of PRV sale amounts in the future.

 

Forward-looking statements are presented as of the date of this press release. Except as required by law, we do not intend to update any forward-looking statements.

 

Investor & Media Contact

Investors: WaterSeid Partners, Inc. — ATOS@waterseid.com

 


 

Media: Elev8 New Media — atossa@elev8newmedia.com

 

 

 

 

 


 

ATOSSA THERAPEUTICS, INC.

CONDENSED CONSOLIDATED BALANCE SHEETS

(amounts in thousands, except share and per share data)

(Unaudited)

 

 

 

 

 

 

 

 

 

 

 

March 31, 2026

 

 

December 31, 2025

 

Assets

 

 

 

 

 

 

Current assets

 

 

 

 

 

 

Cash and cash equivalents

 

$

31,718

 

 

$

41,299

 

Restricted cash

 

 

110

 

 

 

110

 

Prepaid materials

 

 

3,013

 

 

 

3,081

 

Prepaid expenses and other current assets

 

 

1,827

 

 

 

1,128

 

Total current assets

 

 

36,668

 

 

 

45,618

 

Other assets

 

 

1,275

 

 

 

1,990

 

Total assets

 

$

37,943

 

 

$

47,608

 

 

 

 

 

 

 

 

Liabilities and stockholders' equity

 

 

 

 

 

 

Current liabilities

 

 

 

 

 

 

Accounts payable

 

$

2,569

 

 

$

4,293

 

Accrued expenses

 

 

2,807

 

 

 

1,307

 

Payroll liabilities

 

 

943

 

 

 

1,558

 

Other current liabilities

 

 

1,138

 

 

 

1,097

 

Total current liabilities

 

 

7,457

 

 

 

8,255

 

Total liabilities

 

 

7,457

 

 

 

8,255

 

 

 

 

 

 

 

 

Commitments and contingencies

 

 

 

 

 

 

 

 

 

 

 

 

 

Stockholders' equity

 

 

 

 

 

 

Convertible preferred stock - $0.001 par value; 10,000,000 shares authorized;
   577 shares issued and outstanding as of March 31, 2026 and December 31, 2025

 

 

 

 

 

 

Common stock - $0.18 par value; 350,000,000 shares authorized; 8,611,361 shares issued and outstanding as of March 31, 2026 and December 31, 2025

 

 

1,550

 

 

 

1,550

 

Additional paid-in capital

 

 

286,562

 

 

 

285,840

 

Treasury stock, at cost; 88,003 shares of common stock at March 31, 2026 and December 31, 2025

 

 

(1,475

)

 

 

(1,475

)

Accumulated deficit

 

 

(256,151

)

 

 

(246,562

)

Total stockholders' equity

 

 

30,486

 

 

 

39,353

 

Total liabilities and stockholders' equity

 

$

37,943

 

 

$

47,608

 

 

 

 


 

ATOSSA THERAPEUTICS, INC.

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS

(amounts in thousands, except share and per share data)

(Unaudited)

 

 

 

 

For the Three Months Ended March 31,

 

 

2026

 

 

2025

 

Operating expenses

 

 

 

 

 

 

Research and development

 

$

4,779

 

 

$

4,157

 

General and administrative

 

 

5,091

 

 

 

3,257

 

Total operating expenses

 

 

9,870

 

 

 

7,414

 

Operating loss

 

 

(9,870

)

 

 

(7,414

)

Interest income

 

 

309

 

 

 

720

 

Other expense, net

 

 

(28

)

 

 

(24

)

Loss before income taxes

 

 

(9,589

)

 

 

(6,718

)

Income tax benefit

 

 

 

 

 

 

Net loss

 

$

(9,589

)

 

$

(6,718

)

Net loss per share of common stock - basic and diluted

 

$

(1.11

)

 

$

(0.78

)

Weighted average shares outstanding used to compute net loss per share - basic and diluted

 

 

8,622,289

 

 

 

8,622,289

 

 

 

 


FAQ

How did Atossa Therapeutics (ATOS) perform financially in Q1 2026?

Atossa reported a net loss of $9.6 million in Q1 2026, compared with $6.7 million a year earlier. Total operating expenses rose to $9.9 million as the company increased spending on (Z)-endoxifen clinical programs and legal costs tied to patent and intellectual property matters.

What were Atossa Therapeutics’ operating expenses in the first quarter of 2026?

Total operating expenses were $9.9 million in Q1 2026, up from $7.4 million in Q1 2025. Research and development expenses were $4.8 million, while general and administrative costs grew to $5.1 million, mainly due to higher legal fees and intellectual property-related spending.

What is Atossa Therapeutics’ cash position as of March 31, 2026?

As of March 31, 2026, Atossa held $31.7 million in cash and cash equivalents, plus $0.1 million in restricted cash. Total assets were $37.9 million and total liabilities $7.5 million, with stockholders’ equity of $30.5 million supporting its clinical-stage operations.

What regulatory designations has (Z)-endoxifen received for Atossa Therapeutics?

Atossa’s (Z)-endoxifen has FDA Orphan Drug Designation for Duchenne Muscular Dystrophy and Rare Pediatric Disease designation for both Duchenne Muscular Dystrophy and McCune-Albright Syndrome. These designations may make a future approved product eligible for a Priority Review Voucher from the FDA.

How is Atossa Therapeutics advancing (Z)-endoxifen in Duchenne Muscular Dystrophy (DMD)?

Atossa presented preclinical data showing (Z)-endoxifen improved muscle strength, increased lean mass, and reduced biochemical markers of muscle damage in dystrophic mouse models. Management believes these results support advancing (Z)-endoxifen into clinical development for Duchenne Muscular Dystrophy, subject to future study outcomes.

What drove the increase in general and administrative expenses at Atossa in Q1 2026?

General and administrative expenses rose to $5.1 million in Q1 2026 from $3.3 million a year earlier. The company cites a $1.8 million increase in legal fees related to ongoing patent litigation, which has since been settled, and costs for managing its intellectual property portfolio and other legal matters.

Filing Exhibits & Attachments

2 documents