Every 8-K that Atossa Therapeutics, Inc. (ATOS) has filed with the SEC in the last 24 months is listed below, newest first, and each one links through to the document itself with the summary and the scores our analysis gives it.
A 8-K covers material events a company has to report between its quarterly reports, so if you follow ATOS and want that one kind of document rather than the whole filing history, this is the page to keep. The company's other filings, of every form, are on the full ATOS filings page.
Atossa Therapeutics, a clinical-stage biopharmaceutical company focused on its lead candidate (Z)-endoxifen, reported financial results and a corporate update for the second quarter ended June 30, 2026. Total operating expenses were $8.7 million for the quarter and $18.6 million for the first half of 2026.
In Q2 2026, research and development expense was $4.9 million and general and administrative expense was $3.8 million. Net loss was $8,491 thousand for the quarter and $18,080 thousand year-to-date, with a basic and diluted net loss per share of $0.95 and $2.06, respectively. Cash and cash equivalents were $26,094 thousand at June 30, 2026.
Atossa highlighted new preclinical and clinical data supporting (Z)-endoxifen in McCune‑Albright Syndrome, Duchenne Muscular Dystrophy, and ER+ breast cancer, and completed enrollment in the EVANGELINE Phase 2 neoadjuvant breast cancer trial. A registered direct offering raised $4.5 million upfront and could provide up to an additional $12 million in gross proceeds to support (Z)-endoxifen development and general working capital.
Atossa Therapeutics entered into a securities purchase agreement for a registered direct offering of 1,363,638 shares of common stock together with Series A and short-term Series B warrants, at a combined price of $3.30 per share and accompanying warrants. The Series A and Series B warrants each cover up to 1,363,638 shares at an exercise price of $4.40 per share, with exercises beginning six months after issuance; the Series A warrants expire 5.5 years after issuance and the Series B warrants expire two years after issuance. Atossa expects net proceeds of approximately $4.1 million from the share and warrant sale and may receive up to about $12 million in additional gross proceeds if all Series Warrants are exercised for cash. The company plans to use the net proceeds for clinical development of its product candidates, working capital and general corporate purposes.
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.
Atossa Therapeutics, Inc. reported results of its 2026 Annual Meeting of Stockholders. As of the March 19, 2026 record date, 8,611,361 shares of common stock were entitled to vote. Stockholders elected three Class II directors and ratified Ernst & Young LLP as independent registered public accounting firm.
Stockholders also approved an amendment to the Amended and Restated Certificate of Incorporation authorizing a reverse stock split at a ratio from 2:1 to 20:1, if the board determines it is necessary or appropriate. In addition, stockholders approved, on a non-binding advisory basis, the compensation of the company’s named executive officers.
Atossa Therapeutics, Inc. entered into a Settlement Agreement with Intas Pharmaceuticals Ltd. and Jina Pharmaceuticals, Inc. to resolve patent disputes over Endoxifen-related intellectual property, including pending challenges before the U.S. Patent and Trademark Office’s Patent Trial and Appeal Board.
The parties agreed to seek termination of the identified PTAB proceedings and, if any proceeding is not fully terminated, not to participate further in that proceeding or related appeals, subject to the agreement’s terms. They also exchanged mutual covenants not to challenge specified Endoxifen-related patents and applications, with limited exceptions.
The agreement preserves Atossa’s ability to continue developing and commercializing Z-endoxifen base in its principal focus areas of oncology, endocrine dysfunction disorders and muscular dystrophy-related diseases, and allocates certain other Endoxifen-related fields and formulations among the parties. Atossa expects its two issued “Methods for Making and Using Endoxifen” U.S. patents to remain issued and fully enforceable against other third parties, and believes the settlement reduces uncertainty around its patent portfolio and supports its strategic development plans.
Atossa Therapeutics reported a larger net loss of $34.8M for the year ended December 31, 2025, compared with $25.5M a year earlier, as it increased investment in its lead drug candidate, (Z)-endoxifen.
Total operating expenses rose to $37.1M from $27.6M. Research and development spending climbed 50% to $21.2M, driven mainly by an extra $6.1M on clinical and non-clinical trials and higher regulatory consulting tied to (Z)-endoxifen. General and administrative costs increased 18% to $16.0M, reflecting higher legal expenses related to litigation and patent defense and modestly higher compensation.
The company ended 2025 with cash and cash equivalents of $41.3M, down from $71.1M as it funded operations, while interest income fell to $2.4M from $4.1M due to lower average invested balances. During the year, Atossa secured FDA Rare Pediatric Disease and Orphan Drug designations for (Z)-endoxifen in Duchenne Muscular Dystrophy and strengthened its clinical leadership team to support both breast cancer and rare disease programs.
Atossa Therapeutics, Inc. entered into a new at-the-market equity offering agreement with Rodman & Renshaw LLC, allowing the company to sell up to $50,000,000 of its common stock from time to time. Shares will be issued under an existing Form S-3 shelf registration and a related prospectus supplement.
Rodman & Renshaw will act as sales agent or principal and earn a commission of up to 3.0% of gross proceeds, plus reimbursed expenses. Atossa plans to use any proceeds mainly for clinical development of its product candidates, as well as working capital and general corporate purposes, with potential future business or asset acquisitions.
The company also terminated its prior Open Market Sale agreement with Jefferies LLC, effective February 19, 2026, incurring no termination penalties and having sold no shares under that earlier arrangement.
Atossa Therapeutics, Inc. received notice from Nasdaq on February 17, 2026 that it has regained compliance with the Nasdaq Capital Market’s minimum bid price listing rule. The company’s stock met the requirement to maintain a closing bid price of at least $1.00 per share for 10 consecutive trading days, achieved as of the close on February 13, 2026.
Atossa had previously been notified on February 21, 2025 that it was out of compliance with the $1.00 minimum bid price and was granted an extension through February 17, 2026 to correct the deficiency. With compliance restored, the company’s common stock will continue to be listed and traded on the Nasdaq Capital Market.
Atossa Therapeutics furnished an 8-K to share its 2026 Letter to Shareholders, outlining progress and plans for lead candidate (Z)-endoxifen. The company highlighted a late-2025 FDA Type C meeting that clarified expedited regulatory options in multiple breast cancer settings and ongoing I-SPY 2 neoadjuvant studies, with preliminary combination-therapy data expected in 2026. Atossa obtained Rare Pediatric Disease and Orphan Drug designations for (Z)-endoxifen in Duchenne Muscular Dystrophy, and is exploring additional non-oncology uses. Management paused investment in metastatic breast cancer trials to prioritize higher-return indications, strengthened its leadership team, and reported entering 2026 with more than $40 million in cash and cash equivalents. The company also completed a reverse stock split effective February 2, 2026 to help regain Nasdaq listing compliance.
Atossa Therapeutics, Inc. is implementing a 1-for-15 reverse stock split of its common stock, effective at 12:01 a.m. Eastern Time on February 2, 2026. At that time, each 15 shares of common stock will automatically be combined into one share, and the stock is expected to begin trading on a split-adjusted basis the same day under a new CUSIP, while keeping the ATOS ticker and the $0.18 par value per share.
No fractional shares will be issued; instead, stockholders will receive cash equal to the fractional share multiplied by the closing price of the stock on January 30, 2026, adjusted for the split. The company will make proportional adjustments to outstanding equity awards, plan share reserves, and the conversion terms of its Series B Convertible Preferred Stock. The reverse split was enabled by stockholder approval of an amendment allowing a reverse split in a range of 5:1 to 20:1, with 33,724,885 votes for, 27,888,393 against and 130,938 abstentions, out of 129,171,424 shares entitled to vote as of December 19, 2025.
Atossa Therapeutics, Inc. released an updated corporate presentation that includes a preliminary estimate of its cash and cash equivalents. The company estimates it held approximately $40 million in cash and cash equivalents as of December 31, 2025.
This cash figure is unaudited, based on internal closing procedures for the fourth quarter and full year 2025, and may change once final results are completed. Atossa stresses that this estimate alone does not provide a full picture of its financial condition or results of operations and cautions investors not to place undue reliance on it.
The presentation also discusses forward-looking expectations for the development and potential regulatory path of the company’s lead program, (Z)-Endoxifen, including possible indications, approval prospects and market opportunities, all of which are subject to significant clinical, regulatory, financing and Nasdaq listing-compliance risks.
Atossa Therapeutics, Inc. reported that on January 6, 2026 the U.S. Food and Drug Administration issued a “Study May Proceed” letter for the company’s study of metastatic breast cancer. This type of letter indicates the FDA has reviewed the planned clinical study and is allowing it to go forward under its current design.
The company disclosed this development through a press release, which is attached as an exhibit to the report. The update highlights progress in Atossa’s efforts to clinically evaluate its approach in patients with metastatic breast cancer, an advanced stage of the disease where new treatment options are often needed.
Atossa Therapeutics, Inc. filed a current report to furnish a press release announcing its financial results for the quarter ended September 30, 2025 and providing a company update. The press release, dated November 12, 2025, is included as Exhibit 99.1 and incorporated by reference into this report. The company clarifies that the information in Items 2.02 and 9.01, including Exhibit 99.1, is being furnished rather than filed under securities law, which limits its use for certain liability provisions.
Atossa Therapeutics (ATOS) appointed Mark Daniel as Chief Financial Officer and principal accounting officer, effective October 14, 2025, succeeding Heather Rees. Ms. Rees will remain as a non-officer employee through November 15, 2025 to assist the transition and will receive nine months of base salary and nine months of employer-paid COBRA under a separation agreement.
Mr. Daniel’s employment agreement includes a base salary of $415,900 and a target annual bonus of up to 40% of base salary beginning in fiscal 2026. He will receive an option to purchase 578,000 shares with an exercise price set at the grant-date close, vesting 25% on the first anniversary and the remainder in equal quarterly installments over three years. If terminated without Cause or for Good Reason (outside a change in control window), he is eligible for six months’ salary (50% of base) and up to six months of COBRA. Upon qualifying termination in connection with a change in control, benefits include a lump sum equal to 1.0x base salary plus target bonus, pro rata bonus, full equity acceleration, and up to twelve months of COBRA.
Atossa Therapeutics, Inc. reported that it has made an updated corporate presentation available as of September 26, 2025. The presentation is furnished as an exhibit to this report under a Regulation FD disclosure item, meaning it is intended to share information broadly with the market.
The company notes that this material is being furnished, not filed, so it is not subject to certain liability provisions of the federal securities laws and is not automatically incorporated into other SEC filings. The exhibit is identified as a corporate presentation dated September 26, 2025.
Atossa Therapeutics, Inc. filed a current report describing a strategic update. On September 8, 2025, the company announced a new regulatory strategy intended to accelerate development of its low-dose (Z)-endoxifen product candidate for breast cancer risk reduction. The company furnished a press release with further details as an exhibit to this report.
Atossa Therapeutics, Inc. notified Nasdaq that it was not in compliance with the minimum bid price requirement of $1.00 per share under Nasdaq Listing Rule 5550(a)(2) because its common stock failed to maintain a minimum closing bid of $1.00 for 30 consecutive business days. The company's initial compliance period ended on August 20, 2025, and after requesting an extension, Nasdaq granted a 180-day extension on August 21, 2025, moving the deadline to regain compliance to February 17, 2026.
Atossa Therapeutics, Inc. reported on August 12, 2025 that it issued a press release announcing financial results for the quarter ended June 30, 2025 and providing a company update. The press release is attached as Exhibit 99.1 and the filing includes a cover page Interactive Data File as Exhibit 104. The Company states the information in Items 2.02 and 9.01, including Exhibit 99.1, shall not be deemed to be "filed" for purposes of Section 18 of the Exchange Act or subject to certain Securities Act liabilities. This Current Report is signed by Heather Rees, Chief Financial Officer. No numerical financial metrics are included in the 8-K text provided here; consult Exhibit 99.1 for the detailed results and commentary.