Atossa Therapeutics, Inc. $ATOS

By Microcap Ledger desk · CIK 0001488039

Facts as of Oct 11, 2026, 08:15 AM UTC. Built from SEC filings and our own data. Small caps move fast; check the latest filings.

Snapshot

Exchange: Nasdaq Capital Market
Sector: Pharmaceutical Preparations
Headquarters: Seattle, WA
Fiscal year end: December 31
Shares outstanding: 9,979,298 [10-Q 2026-08-07]
as of 2026-07-31

Sources: [10-K 2026-03-25]

What the company doesAI summary of filing

Atossa Therapeutics is a clinical-stage biopharmaceutical company developing therapeutics, with its lead program being (Z)-endoxifen, an active metabolite of Tamoxifen, which is in clinical trials for breast cancer and potentially for Duchenne muscular dystrophy indications. The company is pursuing regulatory approval from the FDA to continue clinical trials and eventually to commercialize its product candidates. Atossa generates no revenue from product sales and instead relies on capital raising to fund its clinical development activities and operating costs. The company intends to partner with organizations for commercialization of approved products. [10-K 2026-03-25]

Segments: (Z)-endoxifen

Financial health

From XBRL company facts (USD)
Period	Revenue	Net income	Operating cash flow	Cash	Filing
6 months to Jun 2026	—	−$18.08M	−$19.23M	$26.09M	[10-Q 2026-08-07]
FY ended Dec 2025	—	−$34.77M	−$29.76M	$41.30M	[10-K 2026-03-25]
FY ended Dec 2024	—	−$25.50M	−$21.03M	$71.08M	[10-K 2026-03-25]

Quarterly cash burn: −$9.61M
Cash runway Estimate: ~8.1 months

Capital structure and dilution

Summary only. How these instruments work: Dilution & financing desk.

Share count
Date	Shares outstanding	Filing
2024-11-08	125,801,254	[10-Q 2024-11-12]
2025-03-17	129,170,004	[10-K 2025-03-25]
2025-05-01	129,170,004	[10-Q 2025-05-13]
2025-08-01	129,171,424	[10-Q 2025-08-12]
2025-11-01	129,171,424	[10-Q 2025-11-12]
2026-03-17	8,611,361	[10-K 2026-03-25]
2026-05-01	8,611,361	[10-Q 2026-05-08]
2026-07-31	9,979,298	[10-Q 2026-08-07]

Shelf registration: S-3 filed 2024-05-13; declared effective 2024-05-23 [S-3 2024-05-13]

Listing status

Current status: 3 Form 8-K Item 3.01 filing(s) in the last 24 months, most recent 2026-02-17. Item 3.01 covers delisting notices, failures to meet a listing rule and listing transfers; read the filing for which one.

Date	Event	Details	Deadline	Filing
2026-02-17	8-K Item 3.01	Notice of delisting or failure to satisfy a continued listing rule or standard; or transfer of listing	—	[8-K 2026-02-17]
2025-08-21	8-K Item 3.01	Notice of delisting or failure to satisfy a continued listing rule or standard; or transfer of listing	—	[8-K 2025-08-21]
2025-02-24	8-K Item 3.01	Notice of delisting or failure to satisfy a continued listing rule or standard; or transfer of listing	—	[8-K 2025-02-24]

More on deficiency notices and uplistings: Listing status desk.

Who owns it

Recent Form 4 transactions
Date	Insider	Type	Shares	Price	Filing
2026-05-12	Steinhart Richard I	grant	10,000	—	[4 2026-05-14]
2026-05-12	Chen Shu-Chih	grant	10,000	—	[4 2026-05-14]
2026-05-12	Remmel H. Lawrence	grant	10,000	—	[4 2026-05-14]
2026-05-12	Finn Jonathan	grant	10,000	—	[4 2026-05-14]
2026-05-12	Galli Stephen J	grant	10,000	—	[4 2026-05-14]
2026-05-12	Cigler Tessa	grant	10,000	—	[4 2026-05-14]
2026-03-27	Quay Steven C	grant	65,000	—	[4 2026-03-31]
2026-03-26	Daniel Mark James	grant	63,000	—	[4 2026-03-30]

Catalysts and calendar

Recent filings and releases
Date	Type	Title
2026-10-09	8-K	Material agreement entered; Change to security holder rights; Other events
2026-09-29	8-K	Other events
2026-09-18	8-K	Regulation FD disclosure
2026-08-07	8-K	Results of operations
2026-08-07	10-Q	Quarterly report
2026-06-12	424B5	Prospectus or prospectus supplement
2026-06-11	8-K	Material agreement entered
2026-05-08	10-Q	Quarterly report
2026-05-08	8-K	Shareholder vote results
2026-04-16	8-K	Other events
2026-03-30	DEF 14A	Proxy statement
2026-03-25	10-K	Annual report

Facts as of Oct 11, 2026, 08:15 AM UTC. Small caps move fast; check the latest filings.