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Atossa Therapeutics, Inc.'s SEC filings document a clinical-stage biopharmaceutical issuer focused on (Z)-endoxifen development in oncology and rare disease settings. Its reports include financial-result 8-Ks, corporate updates, Regulation FD communications, and disclosures tied to research and development spending for its lead product candidate.
The filing record also covers governance and capital-structure matters, including annual meeting votes, director elections, auditor ratification, executive-compensation votes, charter-authority proposals, Form S-3 and at-the-market offering disclosures, Nasdaq listing compliance, and material events involving Endoxifen-related intellectual property proceedings and settlement agreements.
Atossa Therapeutics, Inc. is conducting a registered direct primary offering of 1,363,637 shares of common stock, each sold together with one Series A warrant and one Series B warrant, and placement agent warrants. The offering price is $3.30 per share with aggregate gross proceeds of $4,500,002.10. Net proceeds to the company before expenses are presented as $4,185,001.95 and the company estimates net proceeds after fees and expenses of approximately $4.1 million, to be used for clinical development, working capital and general corporate purposes. The warrants (totaling up to 2,727,274 shares) will be exercisable beginning six months after issuance at an exercise price of $4.40 per share; Series A warrants expire in five and one-half years and Series B warrants expire in two years. The placement agent will receive a cash fee equal to 7.0% of gross proceeds and placement agent warrants equal to 3.0% of shares sold to investors. Shares outstanding after the offering are stated as 9,974,997 (excluding shares issuable upon exercise of warrants and placement agent warrants) based on 8,611,361 shares outstanding as of March 31, 2026.
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.
Steinhart Richard I reported acquisition or exercise transactions in this Form 4 filing.
Atossa Therapeutics director Richard I. Steinhart received an equity award. He was granted 10,000 shares of common stock in the form of restricted stock units, with no cash price per share reported. Following this grant, he holds 10,000 shares directly.
The footnote explains that each RSU represents a contingent right to receive one share of common stock, and the RSUs will vest on the first anniversary of May 12, 2026. This is a compensation-related award, not an open‑market stock purchase or sale.
Chen Shu-Chih reported acquisition or exercise transactions in this Form 4 filing.
ATOSSA THERAPEUTICS, INC. director Shu-Chih Chen reported an equity award and updated holdings. Chen received a grant of 10,000 restricted stock units (RSUs), each representing the right to receive one share of common stock, at a price of $0.0000 per share. The RSUs vest on the first anniversary of May 12, 2026. Following this grant, Chen holds 10,000 common shares directly and 1,483 common shares indirectly through Ensisheim Partners, LLC, where voting and investment power is shared with Dr. Steven C. Quay, and beneficial ownership is disclaimed except to the extent of Chen’s pecuniary interest.
Remmel H. Lawrence reported acquisition or exercise transactions in this Form 4 filing.
ATOSSA THERAPEUTICS, INC. director Remmel H. Lawrence reported a compensation-related stock grant. He received 10,000 restricted stock units, each representing one share of common stock at no cash cost. These RSUs vest on the first anniversary of May 12, 2026. After this award, Lawrence directly holds 10,683 shares of common stock, reflecting a relatively small, routine equity grant rather than an open-market purchase.
Finn Jonathan reported acquisition or exercise transactions in this Form 4 filing.
Atossa Therapeutics director Jonathan Finn received an equity grant of 10,000 shares of Common Stock in the form of restricted stock units. The award was granted at no cash cost per share and is compensation-related, not an open-market purchase. After the grant, Finn directly holds 11,666 shares. According to the footnote, each RSU represents a contingent right to receive one share of Common Stock, and the RSUs shall vest on the first anniversary of May 12, 2026.
Galli Stephen J reported acquisition or exercise transactions in this Form 4 filing.
ATOSSA THERAPEUTICS, INC. director Stephen J. Galli received an award of 10,000 shares of Common Stock in the form of restricted stock units (RSUs) on May 12, 2026. After this grant, he holds 10,006 shares directly. Each RSU represents a contingent right to receive one share of Common Stock and will vest on the first anniversary of May 12, 2026.
Cigler Tessa reported acquisition or exercise transactions in this Form 4 filing.
ATOSSA THERAPEUTICS, INC. director Tessa Cigler reported an equity award of 10,000 shares of Common Stock on May 12, 2026. The award is structured as restricted stock units (RSUs), with each RSU representing a contingent right to receive one share of Common Stock.
The RSUs vest on the first anniversary of May 12, 2026, meaning they become deliverable as shares after that date if vesting conditions are satisfied. Following this grant, Cigler is shown as directly holding 10,000 shares of Common Stock.
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 a larger net loss of $9.6M for the quarter ended March 31, 2026, with no revenue as it remains a clinical-stage company focused on (Z)-endoxifen programs in oncology and rare diseases. Operating expenses rose to $9.9M, driven mainly by higher clinical trial spending and legal fees tied to patent matters. Cash, cash equivalents and restricted cash fell to $31.8M, and management disclosed working capital of $29.2M and ongoing negative cash flows, stating that these conditions raise substantial doubt about the company’s ability to continue as a going concern. Atossa put in place a new at-the-market equity program of up to $50M, effected a 1-for-15 reverse stock split, and highlighted FDA Rare Pediatric Disease and orphan designations for (Z)-endoxifen in Duchenne muscular dystrophy and McCune‑Albright Syndrome.